SKF spherical plain bearings and rod ends

www.bergab.ru Берг АБ bergab@ya.ru Тел. (495)-228-06-21, факс (495) 223-3071 

SKF spherical plain bearings 

and rod ends 

www.bergab.ru Берг АБ bergab@ya.ru Тел. (495)-228-06-21, факс (495) 223-3071


Contents 

The SKF brand now stands for more than ever before, 

and means more to you as a valued customer. 

While SKF maintains its leadership as the hallmark of 

quality bearings throughout the world, new dimensions 

in technical advances, product support and services 

have evolved SKF into a truly solutions-oriented supplier, 

creating greater value for customers. 

These solutions encompass ways to bring greater 

productivity to customers, not only with breakthrough 

application-specific products, but also through leadingedge 

design simulation tools and consultancy services, 

plant asset efficiency maintenance programs, and the 

industry’s most advanced supply management 

techniques. 

The SKF brand still stands for the very best in rolling 

bearings, but it now stands for much more. 

SKF – The knowledge engineering company 

1 Product information ................................................ 4 

Where self-alignment is called for ................................ 4 

When flexibility pays ...................................................... 6 

An incomparable range ................................................. 9 

Multi-purpose performance .......................................... 12 

2 Recommendations .................................................. 16 

Selection of bearing size ............................................... 16 

Load ratings ................................................................. 16 

Basic rating life ............................................................ 17 

Load............................................................................. 18 

Equivalent dynamic bearing load ............................ 18 

Equivalent static bearing load ................................. 20 

Permissible loads for rod ends................................ 20 

Requisite bearing size.................................................. 21 

Specific bearing load............................................... 21 

Mean sliding velocity ............................................... 21 

Basic rating life ............................................................ 24 

Sliding contact surface combinations 

requiring maintenance: steel-on-steel and 

steel-on-bronze ....................................................... 24 

Maintenance-free sliding contact surface 

combination steel/sinter bronze composite ............ 26 


combination steel/PTFE fabric ................................ 27 


combination steel/PTFE composite ........................ 29 

Variable load and sliding velocity ............................ 30 

Calculation examples................................................... 30 

Friction ............................................................................ 35 

Application of bearings.................................................. 36 

Radial location of bearings .......................................... 36 

Axial location of bearings............................................. 40 

Sealing ......................................................................... 43 

Designing the bearing arrangement for easy 

mounting and dismounting .......................................... 46 

Lubrication ...................................................................... 48 

Spherical plain bearings requiring maintenance.......... 48 

Maintenance-free spherical plain bearings.................. 48 

Rod ends requiring maintenance................................. 50 

Maintenance-free rod ends.......................................... 50 

Maintenance ................................................................... 51 

Mounting ......................................................................... 52 

Spherical plain bearings ............................................. 52 

Rod ends ..................................................................... 54 

Dismounting.................................................................... 55 

Spherical plain bearings ............................................. 55 

Rod ends ..................................................................... 55 

2 



3 Product data ............................................................ 57 

Radial spherical plain bearings 

requiring maintenance .................................................. 58 

General ....................................................................... 58 

Steel-on-steel spherical plain bearings 

with metric dimensions............................................ 62 

with inch dimensions............................................... 66 

with extended inner ring.......................................... 70 

Maintenance-free radial spherical plain bearings ...... 72 

General ....................................................................... 72 

Bearings with sliding contact surface combination 

steel/sinter bronze composite ................................ 76 

steel/PTFE fabric ..................................................... 78 

steel/PTFE composite ............................................ 82 

Angular contact spherical plain bearings .................... 86 

General ........................................................................ 86 

Maintenance-free bearings with sliding contact 

surface combination steel/PTFE composite ............... 90 

Spherical plain thrust bearings ..................................... 92 

General ........................................................................ 92 


surface combination steel/PTFE composite................ 94 

Rod ends requiring maintenance ................................. 96 

General ....................................................................... 96 

Steel-on-steel rod ends 

with female thread ...................................................100 

with female thread for hydraulic cylinders ..............102 

with male thread .....................................................104 

with cylindrical section welding shank ....................106 

with rectangular section welding shank .................108 

Steel-on-bronze rod ends 



Maintenance-free rod ends ...........................................114 

General ........................................................................114 

Maintenance-free rod ends 

with female thread, steel/sinter bronze composite 118 

with male thread, steel/sinter bronze composite ....120 

with female thread, steel/PTFE fabric .....................122 

with male thread, steel/PTFE fabric ........................124 

with female thread, steel/PTFE composite..............126 

with male thread, steel/PTFE composite ................128 

Special solutions and related products........................130 

Plain bearings for road vehicles ..................................130 

Plain bearings for rail vehicles ....................................130 

Spherical plain bearings and rod ends for 

airframe applications ..................................................131 

Dry sliding bushings and flanged bushings.................132 

Dry sliding thrust washers and strip ...........................133 

Product information . . . . . . . . . . . . . . . . . . . . . . . 4 

Recommendations . . . . . . . . . . . . . . . . . . . . . . . . 16 

Product data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 


requiring maintenance . . . . . . . . . . . . . . . . . . . . . 58 

Maintenance-free radial spherical 

plain bearings . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 

Angular contact spherical plain bearings . . . . . 86 

Spherical plain thrust bearings . . . . . . . . . . . . . . 92 

Rod ends requiring maintenance . . . . . . . . . . . . 96 

Maintenance-free rod ends . . . . . . . . . . . . . . . . . 114 

Special solutions and related products . . . . . . . 130 

1 

2 

3 

3.1 

3.2 

3.3 

3.4 

3.5 

3.6 

3.7 

SKF – The knowledge engineering company .........134 


3

1 Product information 2 Recommendations 3 Product data 


User benefits Page .............. 16 Page .............. 57 

Where self-alignment is called for 

Spherical plain bearings 

Spherical plain bearings are standardized, 

ready-to-mount mechanical components 

that are self-aligning and enable 

multi-directional alignment movements 

to be made. The inner ring has 

a sphered convex outside diameter 

and the outer ring a correspondingly 

sphered but concave inside surface 

(➔ fig 1 ). The forces acting on the 

bearing may be static or may occur 

when the bearing makes oscillating 

or recurrent tilting and slewing movements 

at relatively low speeds. 

The advantages inherent in the design 

of spherical plain bearings mean 

that in practice 

• errors of alignment or angular misalignment 

do not influence bearing 

life 

• deformation of surrounding components 

in operation has no effect 

• edge stresses and excessive stressing 

of adjacent components do not 

occur 

• operational reliability of lightweight 

constructions is enhanced 

• reasonably wide manufacturing 

tolerances allow the use of costfavourable 

welded constructions 

Operational reliability is high even when 

a design is made more compact – edge 

stresses and overloading do not occur 

Misalignment is not a problem for 

spherical plain bearings 

1 

2 

3 

4 

5 

6 

Fig 

1 Spherical plain 

bearing 

1 Outer ring 

2 Sliding contact 

surfaces 

3 Seal 

4 Inner ring 

5 Lubrication hole 

6 Lubrication groove 

4 




User benefits Page .............. 16 Page .............. 57 

1 

Deformation in operation does not have 

influence on bearing life 

Wide manufacturing tolerances are 

accommodated = cost-favourable 

welded constructions 

Rod ends 

Rod ends are bearing units that consist 

of a spherical plain bearing in an 

eye-shaped head with integral shank: 

the rod end housing (➔ fig 2 ). They 

are used primarily on the ends of piston 

rods or together with hydraulic as 

well as pneumatic cylinders to join the 

cylinder to associated components. 

Rod end 

1 Spherical plain 

bearing 

2 Rod end 

2a Rod end housing 

(eye) 

2b Rod end shank 

3 Lubrication 

nipple 

1 

2a 

3 

2 

Fig 

2 

2b 


5



Design features Page .............. 16 Page .............. 57 

When flexibility pays 

SKF spherical plain bearings and rod 

ends should be the first choice for total 

design economy. These state-of-theart 

products are stocked in a wide 

range of designs, dimension series 

and sizes. 

Whether a large bearing is required, 

or a small maintenance-free rod end – 

both are available from SKF and offer: 

• long service life, 

• simple maintenance and 

• high operational reliability. 

Easy replaceability is also provided 

as all SKF spherical plain bearings and 

rod ends are standardized products. 

Their worldwide availability goes without 

saying – thanks to the global SKF 

sales organisation. 

It is not just total economy considerations 

that point to SKF spherical plain 

bearings and rod ends, but also their 

unparalleled design characteristics. 

Some of the advantages are outlined 

in the following. 

Mature, well-proven designs 


ends offer the performance to meet 

application demands. The designs, 

materials and manufacturing quality 

have been selected for long service 

lives and reliability. “Fit and forget” is 

a philosophy embraced by SKF. 

Easily maintainable sliding contacts 

for heavy loads 

SKF steel-on-steel spherical plain 

bearings have high-strength sliding 

contact surfaces of carbon chromium 

(rolling bearing) steel which are phosphated 

and treated with a special 

running-in lubricant. Their prime areas 

of use are where 

• heavy static loads and 

• heavy alternating loads and 

• high-frequency alignment or oscillating 

movements 

occur. 

They are also relatively insensitive to 

contamination and high temperatures. 

These advantages come at a price – in 

this case the need for maintenance. 

Therefore, lubrication holes and 

grooves are provided in both the inner 

and outer rings of all bearings – with 

the exception of a few small sizes – to 

facilitate relubrication. To further enhance 

lubrication, all bearings having 

an outside diameter of 150 mm and 

above incorporate the “multi-groove 

system” in the sliding surface of the 

outer ring. 

SKF steel-on-bronze rod ends also 

require maintenance, although requirements 

are less stringent than for steelon-steel 

rod ends, as the emergency 

running properties are better. 

The multi-groove system 

Standard steel-on-steel spherical plain 

bearings that have to perform minor 

alignment movements under very 

heavy, constant direction loads have a 

lubricant starvation problem. The SKF 

multi-groove system is the answer to 

this. The multi-groove system 

• improves lubricant supply to the 

loaded zone, 

• enlarges the lubricant reservoir in the 

bearing, 

• enables relubrication under load, 

• permits extended relubrication intervals 

and 

• provides space for wear particles and 

contaminants to be deposited 

All in all the system improves lubricant 

distribution in the heavily loaded 

zone and thus extends the service life 

and/or maintenance intervals. 

Radial spherical 

plain bearing 

Angular contact 

spherical plain 

bearing 

Spherical plain 

thrust bearing 

Rod end with 

female thread 

Rod end with male 

thread 

Rod end with 

welding shank 

6 





Maintenance-free, long-life sliding 

contact surfaces 

All freedom, as also freedom from 

maintenance, has a price. In this case 

a one-off cost – the purchase price. 

Once installed, maintenance-free 

spherical plain bearings and rod ends 

require no or very little maintenance. 

The initial higher price is largely compensated 

by the cost of the maintenance 

that is avoided. As to offer maintenance-free 

solutions in a large number 

of applications SKF produces 


with different sliding contact surface 

combinations (partly size-dependent): 

• steel/sinter bronze composite, 

• steel/PTFE fabric and 

• steel/PTFE composite. 

The self-lubricating dry sliding materials 

of the maintenance-free sliding 

contacts are not as strong as steel 

and consequently deform more under 

load. This makes these bearings more 

sensitive to alternating or “hammering” 

loads so that steel-on-steel bearings 

should be used under such conditions. 

Maintenance-free spherical 

plain bearings and rod ends are designed 

for types of duty where 

• loads are heavy and are of constant 

direction, or 

• friction should be low and also constant, 

or 

• relubrication is impossible or 

undesirable. 

Maintenance-free, 

long-life sliding 

contact surfaces 

Sinter bronze 

composite 

PTFE fabric 

PTFE composite 

1 

In the first two combinations, the steel 

is hard chromium plated. 


7




Free choice of materials 

There is a free choice of materials. In 

most applications, SKF spherical plain 

bearings of through hardened steel are 

the best choice; but in difficult environmental 

conditions, SKF maintenancefree 

stainless steel spherical plain bearings 

may be preferred. Please contact 

the SKF application engineering service 

for other options. It is not necessary 

to be limited or make compromises. 

With or without seals 

SKF also provides a choice of seals. 

The most popular sizes of standard 

bearings are available with and without 

seals. Sealed bearings provide opportunities 

to solve many sealing problems 

simply by using standard bearings, 

saving space and above all expense. 

The double lip seal integral 

with the face of the outer ring efficiently 

protects the sliding contact surfaces 

from contaminants in normal environments. 

If environmental conditions are 

difficult, the SKF high-performance 

seals of the LS design should be considered 

(➔ page 44). The operational 

reliability of the bearing arrangement 

will be much enhanced – a benefit for 

original equipment manufacturers as 

well as their customers. 

Wide operating temperature range 

Temperature is not a problem. There is 

a choie of SKF spherical palin bearings 

and rod ends for temperatures 

ranging from –50 to +300 °C. 

Minimal maintenance 

Fit and forget applies to most SKF 

spherical plain bearings and rod ends. 

They are maintenance-free. In some 

applications, where heavy loads and 

difficult environments prevail, there 

might be a need for some maintenance. 

However, this need is minmal for 

SKF plain bearings, as there is an optimal 

choice of five different sliding contact 

surface combinations and also 

seals executions are available. 

Exhaustive range 

The SKF range starts with bearings 

having a 4 mm bore and the rod end 

range covers almost all normal requirements. 

More information will be found 

in the following section. 

Choice of materials 

Bearings of rolling bearing steel for normal 

conditions and, for difficult environments, 

bearings of stainless steel 

With or without seals 

Many sealing problems can be solved economically 

and in a space-saving manner 

using sealed bearings that dominate the 

SKF range 

–50 +300 

Wide permissible operating temperature 

range 

Open steel-on-steel spherical plain bearings 

can operate at temperatures ranging 

from –50 to +300 °C 

N 

NSKF 

N 

Minimum maintenance 

The multi-groove system dramatically 

extends maintenance intervals for steel-onsteel 


8 




Product overview Page .............. 16 Page .............. 57 

An incomparable range 

1 

All the products shown here belong to 

the SKF standard range. 

• Radial spherical plain bearings 

requiring maintenance 

• Maintenance-free spherical plain 

bearings 

• Angular contact spherical plain bearings 

• Spherical plain thrust bearings 

• Steel-on-steel rod ends requiring 

maintenance 

• Steel-on-bronze rod ends requiring 

maintenance 

• Maintenance-free rod ends 

If the standard range does not fulfill 

the requirements, SKF can produce 

special bearings, provided quantities 

permit manufacturing economy. The 

design will be specially tailored to 

meet particular application demands. 

Nothing is too much trouble. 


9



Product range overview Page .............. 16 Page .............. 57 

GE .. E 

GE .. ES 

GEM .. ES 

GEG .. ES 

GEZ .. ES 

GEH .. ES 

GE .. ES-2RS 

GE .. ES-2LS 

GEM .. ES-2RS 

GEG .. ES-2RS 

GEZ .. ES-2RS 

GEH .. ES-2RS 

Radial spherical plain bearings requiring maintenance 

GE .. C 

GE .. TXE-2LS 

GE .. TXG3E-2LS 

GE .. TXGR 

GEC .. FSA 

GEP .. FS 

GEH .. C 

GE .. CJ2 

GE .. TXA-2LS 

GE .. TXG3A-2LS 

GEZ .. TXE-2RS 

GEC .. TXA-2RS 

GEH .. TXE-2LS 

Maintenance-free radial spherical plain bearings 

Angular contact spherical plain bearings 

Spherical plain thrust bearings 

GAC .. F GAC .. TX GAC .. SA GAZ .. SA 

GX .. F 

GX .. TX 

to order to order to order to order 

10 




Product range overview Page .............. 16 Page .............. 57 

SI(L) .. E 

SA(L) .. E 

SI(L) .. ES/ES-2RS 

SA(L) .. ES/ES-2RS 

SI(L)A .. ES-2RS 

SA(L)A .. ES-2RS 

SIJ .. ES 

SIR .. ES 

SIQG .. ES 

SI(L)KAC .. M 

SA(L)KAC .. M 

1 

Rod ends with threaded shank requiring maintenance 

Designation 

suffix 

Dry sliding surface 

C 

F 

TX 

sinter bronze composite 

PTFE composite 

PTFE fabric, embedded in 

phenolic or epoxy resin 

SC .. ES 

SCF .. ES 

For detailed information on these materials, see page 72 

Identification of maintenance-free sliding materials 

Rod ends with welding shank requiring 

maintenance 

Maintenance-free rod ends with threaded shank 

SI(L) .. C 

SA(L) .. C 

SI(L) .. TXE-2LS 

SA(L) .. TXE-2LS 

SI(L)A .. TXE-2LS 

SA(L)A .. TXE-2LS 

SI(L)KB .. F 

SA(L)KB .. F 

Caption heading 


11



Application areas Page .............. 16 Page .............. 57 

Multi-purpose performance 

Long life, high reliability, minimum 

maintenance and a representative 

product range are strong arguments 

for SKF spherical plain bearings and 

rod ends. As this benefits the user as 

well as the operator, a wide range of 

applications in almost all sectors of 

industry has evolved. Typical use of 


requiring maintenance are found in 

• the steel construction industry, 

• cranes, 

• fork lift trucks, 

• hydraulic cylinders, 

• stabilizers, 

• mineral processing equipment, 

• rolling mill equipment and 

• linkages of all kinds in construction 

and earth-moving machines and 

equipment. 

Application areas where maintenancefree 

spherical plain bearings and rod 

ends are used include 

• conveyors, 

• industrial robots, 

• textile and printing machinery, 

• switching levers, 

• packaging as well as food and beverage 

treatment machines, and last 

but not least 

• the many uses in segment gates, 

barrages and similar installations. 

SKF spherical plain bearings and 

rod ends are in use around the world. 

Some well-proven applications are 

shown in the following as examples. 

Suspended roof 


bearings have been in service in an 

unusual, but world-renowned application 

for more than 30 years – the roof 

of the Olympia Stadium in Munich. Although 

this type of bearing requires 

maintenance, none has been given to 

these particular bearings. 

The roof is constructed of a number 

of prestressed steel ropes in a network. 

At the torque-free nodal points 

of the network 225 completely normal 


bearings having bore diameters ranging 

from 160 to 300 mm do their duty. 

The nodes are statically loaded but 

must allow occasional oscillations of 

the roof construction. 

What better proof could there be for 

staying power, robustness and 

longevity? 

Nodal point of 

suspended roof 

construction 

12 





Articulated pendulum joint 

of a wheel loader 

Three SKF steel-on-steel spherical 

plain bearings with the multi-groove 

lubrication system are used for the 

bearing arrangement of the articulated 

pendulum joint of this wheel loader. 

Two of the bearings provide the articulation. 

The third bearing together with a 

cylindrical sliding bushing in the pendulum 

joint serves to compensate for 

uneven ground so that the driven 

wheels adhere well to the surface. 

The multi-groove lubrication system 

of SKF spherical plain bearings improves 

the transport of lubricant to the 

loaded zone and also enlarges the 

lubricant reservoir in the bearing. 

Neglection of lubrication intervals 

previously led to lubricant starvation, 

this has been solved. 

Heavy-duty performance at no extra 

cost provides much extended service 

lives even with long maintenance intervals. 

1 

Articulated pendulum joint 

of a wheel loader 


13




Truck twin-axle supports 

The purpose of the bearing arrangement 

of a truck twin-axle support is to 

provide even load distribution between 

the two axles on bumpy roads or offhighway. 

This means that the arrangement 

is subjected to heavy loads and, 

depending on the road/off-highway 

conditions, heavy shock loads and 

highly frequent alignment movements. 

The bearings are hidden behind the 

tyres and are difficult to access. It is 

evident that any sudden bearing damage, 

calling for immediate on site repairs 

need to be avoided. 

A pair of SKF angular contact spherical 

plain bearings mounted back-toback 

make sure that such emergencies 

will not occur. They can withstand 

all the rigours of truck duty, are simple 

to install and also to maintain. 

Dam gate 

Truck twin-axle support 

Dam gates 

Segment gates for dam barrages 

are the home of largesize 

SKF maintenance-free 

spherical plain bearings. The 

reference list is long – over 

3 000 applications being included 

to date. 

As main bearings, they compensate 

for non-alignment of their seatings, 

alterations in length as a result of temperature 

changes, elastic deformation 

of the dam gates as well as changes 

caused by settling of the foundations. 

They cope with the heavy radial loads 

caused by the water pressure as well 

as axial loads arising from the inclined 

position of the support arms. 

SKF bearings not only serve as heavily 

loaded bearings under static conditions; 

they also serve in the frequently 

operated linkage attachments of the 

lifting and plunger cylinders as well as 

the flaps. 

14 




Application areas Page .............. 16 Page ............... 57 

Hydraulic and 

pneumatic 

cylinders 

SKF steel-on-steel 

and steel-on-bronze 

rod ends are mainly 

used in these 

applications. They 

act as the link between 

the cylinder 

and its attachments. They are able to 

transmit high mechanical forces. 

Hydraulic cylinders (e.g. to DIN 

24336) are often fitted with steel-onsteel 

rod ends with female thread 

(compressible) at one end and steelon-steel 

rod ends with welding shank 

at the other. Such hydraulic cylinders 

are found in all types of construction 

equipment, agricultural machinery, lifting 

equipment and shutters, recycling 

depot presses as well as other heavily 

loaded manoeuvering equipment. 

For pneumatic cylinders with working 

pressures up to approximately 1 MPa 

steel-on-bronze rod ends are mainly 

used as well as maintenance-free rod 

ends at the piston rod end and at the 

other end SKF rod ends with welding 

shank are employed. 

Newspaper conveyor 

Speed is all-important when producing 

newspapers, not only in the printing 

but also in their transportation. The 

conveyor system from the printing 

press to the distribution point is therefore 

important if the newspapers are to 

come out on time. 

The endless conveyor chain is one 

such system. It consists of a multitude 

of links which together provide the flexibility 

required. In the example shown 

more than 1 000 SKF maintenancefree 

spherical plain bearings GEH 10 C 

are used. They have been in daily service 

without any maintenance whatsoever 

for many years now. 

1 

Hydraulic and 

pneumatic 

cylinders 

Newspaper 

conveyor 


15



Page ................ 4 Load ratings Page .............. 57 

Selection of bearing size 

Load ratings 

There is no standardized method for 

determining the load ratings of spherical 

plain bearings and rod ends, nor 

is there any standardized definition. 

As different manufacturers define load 

ratings differently, it is not possible to 

compare the load ratings of bearings 

produced by one manufacturer with 

those published by another manufacturer. 

Basic dynamic load rating 

The basic dynamic load rating C is 

used, together with other influencing 

factors, to determine the basic rating 

life of spherical plain bearings and rod 

ends. As a rule it represents the maximum 

load that a spherical plain bearing 

or rod end can sustain at room temperature 

when the sliding contact surfaces 

are in relative motion (➔ fig 1 ). 

The maximum permissible load in any 

individual application should always 

be considered in relation to the de- 

sired rating life. The basic dynamic 

load ratings quoted in the product 

tables are based on the specific load 

factor K (➔ Table 4 , page 21) and 

the effective projected sliding surface. 

Basic static load rating 

The basic static load rating C 0 represents 

the maximum permissible load 

that may be applied to a bearing when 

there is no relative movement of the 

sliding contact surfaces (➔ fig 2 ). 

For spherical plain bearings the 

basic static load rating represents the 

maximum load which the bearing can 

accommodate at room temperature 

without its performance being impaired 

as a result of inadmissible deformations, 

fracture or damage to the sliding 

contact surfaces. The basic static 

load ratings quoted for SKF spherical 

plain bearings are based on a specific 

static load factor K 0 (➔ Table 4 , 

page 21) and the effective projected 

sliding surface. It is assumed that the 

bearing is adequately supported by 

the associated components of the 

bearing arrangement. In order to fully 

exploit the static load rating of a spherical 

plain bearing it is generally necessary 

to use shafts and housings of 

high-strength materials. The basic 

static load rating must also be considered 

when bearings are dynamically 

loaded if they are also subjected to 

additional heavy shock loads. The 

total load in such cases must not 

exceed the basic static load rating. 

For rod ends it is the strength of the 

eye-shaped head of the rod end (housing) 

at room temperature under a constant 

load acting in the direction of the 

shank axis which is the determining 

factor. The basic static load rating represents 

a safety factor of at least 1,2 

relative to the yield strength of the material 

of the rod end head under the 

above conditions. 

Dynamic bearing load Static bearing load Angle of oscillation 

Fig 1 

Fig 2 

Fig 

3 

3 

β 

0 

2 

4 

ϕ 

ϕ = angle of oscillation = 2 β 

A complete oscillation is from point 0 to point 4 and 

= 4 β 

1 

16 




Page ................ 4 Basic rating life Page .............. 57 

Basic rating life 

Spherical plain bearings belong to the 

category “dry sliding bearings”. In contrast 

to, say, hydrodynamic plain bearings, 

no lubricant film can form to fully 

separate the sliding surfaces. Therefore, 

under dynamic loads wear is naturally 

produced which enlarges the 

internal clearance. 

The service life of a spherical plain 

bearing or rod end represents the operating 

period under test conditions 

which is ended when one of the criteria 

listed in Table 1 for the end of service 

life is reached. The life is expressed 

either in operating hours or in the number 

of oscillating movements (➔ fig 3 ). 

A distinction is made between the 

basic rating life and the service life actually 

achieved. 

The basic rating life is a guideline 

value which will be attained or exceeded 

by the majority of a large number 

of apparently identical bearings 

under the same test conditions. 

The service life achieved by identical 

bearings has been found to differ, 

as the service life depends on the actual 

operating conditions. These include 

not only the magnitude and type of 

load but also other factors such as 

contamination, corrosion, load and 

movement cycles of high frequency, 

and shock loads. These factors are 

difficult or even impossible to quantify. 

Calculation of basic rating life 

By using the SKF Interactive Engineering 

Catalogue it is possible to perform 

all the necessary calculations for 

spherical plain bearing selection at the 

click of a mouse using the programs 

incorporated in the catalogue. The 

product data necessary for the calculations 

is automatically put in by selecting 

a spherical plain bearing or rod end 

from the product tables. It is then only 

necessary to fill in the fields for the 

operating data. 

The SKF Interactive Engineering 

Catalogue is available on CD-ROM or 

online at www.skf.com. 

2 

Criteria for end of service life 

Table 

Sliding contact surface combination Increase Coefficient 

in bearing 

of friction 

clearance µ 

1 

– mm – 

Steel-on-steel > 0,004 d k 0,20 

Steel-on-bronze > 0,004 d k 0,25 

Steel/sinter bronze composite 

constant direction load 0,2 0,20 

alternating direction load 0,4 0,20 

Steel/PTFE fabric 

constant direction load 0,3 0,20 

alternating direction load 0,6 0,20 

Steel/PTFE composite design and 0,25 

size dependent 


17



Page ................ 4 Load Page .............. 57 

Load 

When considering load, a distinction is 

made between: 

• load direction 

– radial loads (➔ fig 4 ) 

– axial loads (➔ fig 5 ) 

– combined (axial and radial) loads 

(➔ fig 6 ) 

• the way in which the load acts 

– loads of constant direction 

(➔ fig 7 ), i.e. the direction in 

which the load is applied does not 

change and the same part of the 

bearing (loaded zone) is always 

subjected to the load 

– alternating loads (➔ fig 8 ), 

change direction so that loaded 

zones at opposite positions in the 

bearing are continuously loaded 

and unloaded 

• the type of load 

– dynamic load is when sliding movement 

takes place in the loaded 

bearing 

– static load is when no movement 

takes place in the loaded bearing. 

Equivalent dynamic bearing 

load 

If the load acting on 

• radial and angular contact spherical 

plain bearings is purely radial 

• spherical plain thrust bearings is 

purely axial 

• rod ends is purely radial and also in 

the direction of the shank axis 

and is of constant magnitude, then the 

load can be directly inserted in the 

equation for the specific bearing load p 

(➔ page 21). In all other cases it is 

necessary to calculate the equivalent 

dynamic bearing load P. If the load is 

not of constant magnitude, then the 

procedure given under “Variable load 

and sliding velocity” (➔ page 30) 

should be followed. 

Radial load Fig 4 

Axial load Fig 5 

Combined load Fig 6 

Constant direction 

load 

Fig 

7 

Alternating 

direction load 

Fig 

8 

18 




Page ................ 4 Load Page .............. 57 


Radial spherical plain bearings can 

accommodate a certain amount of 

axial load F a in addition to the simultaneously 

acting radial load F r (➔ fig 6 ). 

When the resultant load is constant in 

magnitude, the equivalent dynamic 

bearing load can be obtained from 

P = y F r 

where 

P = equivalent dynamic bearing load, 

kN 

F r = radial component of the load, kN 

y = a factor that depends on the ratio 

of the axial to the radial load F a /F r 

– for bearings requiring maintenance 

(➔ Diagram 1 ) 

– for maintenance-free bearings 


Diagram 

1 




When the resultant 

load (➔ fig 9 ) is 

constant in magnitude, 

then 

P=y F r 

where 

P = equivalent dynamic 

bearing 

load, kN 



bearing under 

combined load 

F r = radial component of the load, kN 

y = a factor that depends on the ratio 

of the axial to the radial load F a /F r 


Fig 9 Spherical plain 

thrust bearings 


thrust bearings can 

carry a radial load 

F r in addition to the 

axial load F a . However, 

the radial load 

must not exceed 

50 % of the simultan- 

Fig 10 

eously acting axial 

load (➔ fig 10 ). 

When the resultant 

load is constant in 

magnitude, then 

P=y F a 


thrust bearing 

under combined 

load 

where 


kN 

F a = axial component of the load, kN 

y = a factor depending on the ratio of 

the radial to the axial load F r /F a 


2 

y 

3 

2,5 

2 

1,5 

1 

0 0,05 0,1 0,15 0,2 0,25 

Fa 

Fr 

Factor y for radial spherical plain 

bearings requiring maintenance 

Factor y for maintenance-free radial 


Factor y for angular contact spherical 

plain bearings 

Factor y for spherical plain thrust 


Diagram 

2 

Diagram 

3 

Diagram 

4 

y 

2,5 

2,25 

2 

Other series 

y 

2,5 

2,25 

2 

y 

2 

1,75 

1,75 

1,5 

1,25 

Series 

GEP .. FS 

1,75 

1,5 

1,25 

1,5 

1,25 

1 

0 0,1 0,2 

0,3 0,4 

Fa 

Fr 

1 

0 0,5 1 

If F a /F r > 2, a spherical plain thrust 

bearing should be used instead, or 

SKF should be contacted 

1,5 2 

Fa 

Fr 

1 

0 0,1 0,2 0,3 0,4 0,5 

Fr 

If F r /F a > 0,5, an angular contact Fa 

spherical plain bearing should be used 

instead, or SKF should be contacted 


19



Page ................ 4 Load Page .............. 57 

Equivalent static bearing load 

If spherical plain bearings and rod 

ends are subjected to load when stationary 

or making only slight alignment 

movements, then the permissible load 

is not limited by wear, but by the 

strength of the sliding contact layer or 

the strength of the rod end housing. 

If the actual load is a combined radial 

and axial load, then an equivalent 

static bearing load must be calculated. 

This can be done in a similar way to 

the calculation of the equivalent dynamic 

bearing load, for radial and 

angular contact spherical plain 

bearings using 

P 0 = y F r 

and for spherical plain thrust bearings 

using 

Permissible loads for rod ends 

Rod ends are primarily intended for the 

support of radial loads acting in the direction 

of the shank axis. If loads act at 

right angles to the shank axis (➔ fig 

11 ), the maximum permissible load 

will be reduced as additional bending 

stresses occur in the shank. When 

checking, consideration should also 

be paid to the rod end head (housing) 

material which differs depending on 

design and size. 

The load directed at an angle or 

axially to the rod end (to the direction 

of the shank axis) should never exceed 

the value of 0,1 C 0 . If heavier 

loads are involved then a larger rod 

end should be chosen. 

The maximum permissible load for 

a rod end in the direction of the shank 

axis can be calculated from 

Rod end under combined load 

Fig 

11 

P 0 =yF a 

P perm =C 0 b 2 b 6 

where 

P 0 = equivalent static bearing load, kN 

F r = the radial component of the load, 

kN 

F a = the axial component of the 

load, kN 

y = a factor which depends on the 

ratio F a /F r 

– for radial bearings requiring 

maintenance (➔ Diagram 1 , 

page 19) 

– for maintenance-free radial 

bearings (➔ Diagram 2 , 

page 19) 

– for angular contact spherical 

plain bearings (➔ Diagram 3 , 

page 19) 

and on the ratio F r /F a 

– for spherical plain thrust bearings 

(➔ Diagram 4 , page 19) 

where 

P perm = maximum permissible load, kN 

C 0 = static load rating, kN 

b 2 = temperature factor 

• for rod ends requiring maintenance 

(➔ Table 5 , page 

24) 

• for maintenance-free rod 

ends with the sliding contact 

surface combination 

– steel/sinter bronze composite 


– steel/PTFE fabric 


– steel PTFE composite 


b 6 = factor for the type of load 

(➔ Table 2 ) 

Factor b 6 for rod end load type 

Table 

Type of load 

Factor 

(magnitude and direction) b 6 

Constant 

+ F r 

1 

Pulsating magnitude (single direction) 

2 

+ F r 

0,5 

(0,35) 

Alternating direction, 

+ F r 

– F r 

0,5 

(0,35) 

The values in brackets apply to rod ends with 

lubrication hole or nipple 

20 




Page ................ 4 Selection of bearing size Page .............. 57 

Requisite bearing size 

When determining the requisite size of 

bearing (or rod end), it is necessary to 

know the basic rating life required for 

the particular application. This is dependent 

on the type of machine, the 

operating conditions and the demands 

regarding operational reliability. 

As a first approximation the guideline 

values of the load ratio C/P given 

in Table 3 can be used to obtain the 

requisite basic dynamic load rating C. 

A suitable bearing or rod end can then 

be selected from the product tables. 

It should then be checked whether 

the chosen size can be used under the 

actual load and sliding velocity conditions 

using the appropriate diagram for 

the sliding contact surface combination 

from those shown on pages 22 and 23 

(Diagrams 5 to 10 inclusive). The 

specific bearing load p and the sliding 

velocity v needed to perform this check 

can be calculated as explained in the 

following sections. 

If, having checked the pv diagram, 

it is found that the bearing or rod end 

can be used, then the basic rating life 

Guideline values for C/P 


bearings/rod ends 

with sliding contact 


Steel-on-steel 2 

Steel-on-bronze 2 

Steel/sinter bronze 

composite 1,6 

Steel/PTFE fabric 2 

Steel/glass fibre 

reinforced plastic 

GAC .. F 1,25 

GX .. F 1,25 

GEP .. FS 1,6 

GEC .. FSA 1,6 

Rod ends 1,25 

Table 

Load ratio 

C/P 

3 

is calculated. If the calculated rating 

life is shorter than the requisite rating 

life, a larger bearing or rod end should 

be chosen and the calculation 

repeated. 

If, on the other hand, the first check 

shows the pv range is exceeded, a 

bearing having higher load carrying 

capacity should be chosen. 

The bearing (or rod end) size is 

often dictated to a greater or lesser 

degree by the dimensions of the associated 

components. In such cases the 

pv diagram should be consulted first 

to check that the product can be 

used. 

Specific load factors 

Sliding contact 


Specific load 

factors 

dyn. stat. 

K K 0 

– N/mm 2 

Table 

Steel-on-steel 

Metric sizes 100 500 

Inch sizes 100 300 

Steel-on-bronze 50 80 

Steel/sinter 

bronze composite 100 250 

Steel/PTFE fabric 300 500 

Steel/glass fibre 

reinforced plastic 

GAC .. F 50 80 

GX .. F 50 80 

GEP .. FS 80 120 

GEC .. FSA 80 120 

Rod ends 50 80 

4 

Specific bearing load 

The magnitude of the specific bearing 

load can be determined using 

P 

p = K –– 

C 

where 

p = specific bearing load, N/mm 2 

K = a specific load factor depending on 

the basic dynamic load rating 

(➔ Table 4 ), N/mm 2 


kN 

C= basic dynamic load rating, kN 

Mean sliding velocity 

The mean sliding velocity for constant 

movement can be obtained from 

v = 5,82 × 10 –7 d m β f 

where 

v 

= mean sliding velocity, m/s 

When operation is intermittent 

(not continuous) the mean sliding 

velocity should be calculated for a 

cycle of operation 

d m = mean diameter of inner ring or 

shaft washer, mm 

d m = d k for radial spherical plain 


d m = 0,9 d k for angular contact 


d m = 0,7 d k for spherical plain 


β = half the angle of oscillation 

(➔ fig 3 , page 16), degrees 

For rotation β = 90° 

f = frequency of oscillation, min –1 , 

or rotational speed, r/min 

For intermittent movement, the angle 

of oscillation is usually given per unit 

time. In this case the mean sliding 

velocity can be calculated using 

2 β 

v = 8,73 × 10 –6 d m ––– 

t 

where 

β = half the angle of oscillation, degrees 

t = time taken to pass through 2 β 

(= whole angle of oscillation), s 

2 


21



Page .................... Selection of bearing size Page .............. 57 

200 

p 

N/mm 2 

100 

IV 

Diagram 

5 

pv diagram for sliding contact surface 

combination steel-on-steel 

See Note 1 for explanation of operating 

ranges 

50 

20 

10 

II 

I 

III 

5 

2 

1 

0,0001 0,001 0,002 0,005 0,01 0,02 0,05 0,1 0,2 0,5 

v m/s 

100 

p 

N/mm 2 

50 

Diagram 

6 


combination steel-on-bronze 


ranges 

20 

10 

5 

II 

I 

III 

2 

1 

0,0001 0,001 0,002 0,005 0,01 0,02 0,05 0,1 0,2 0,5 

v m/s 

200 

p 

N/mm 2 

100 

50 

20 

10 

II 

I 

5 

0,0001 0,001 0,002 0,005 0,01 0,02 0,05 0,1 0,2 0,5 1,0 

v m/s 

III 

Diagram 

7 


combination steel/sinter bronze 

composite 


ranges 

Note 1 

pv operating ranges 

I Range where rating life equation is 

valid 

II Quasi-static range; before using the 

rating life equation, please contact 

SKF 

III Possible range of use, e.g. with 

very good lubrication; before using 

the rating life equation, please contact 


IV Extended range where rating life 

equation is valid provided the load 

is exclusively alternating 

22 




Page .................... Selection of bearing size Page .............. 57 


combination steel/PTFE fabric 


ranges 

p 

500 

N/mm 2 100 

Diagram 

8 

200 

2 

50 

20 

10 

II 

I 

III 

5 

0,0001 0,001 0,002 0,005 0,01 0,02 0,05 0,1 0,2 0,5 

v m/s 


combination steel/PTFE composite, 

FS and FSA designs 


ranges 

p 120 

N/mm 2 

100 

Diagram 

9 

50 

III 

20 

II 

I 

10 

5 

0,0001 0,001 0,002 0,005 0,01 0,02 0,05 0,1 0,2 

v m/s 


combination steel/PTFE composite, 

F design 


ranges 

Diagram 

10 

Note 2 

pv operating ranges 

I Range where rating life equation is 

valid 

II Quasi-static range; rating life 

equation has limited validity, see 

under “Basic rating life” starting 

on page 24 

III Possible range of use, e.g. with 

very good heat removal; before 

using the rating life equation, 

please contact SKF 

100 

p 

N/mm 2 

50 

20 

10 

II 

5 

0,0001 0,001 0,002 0,005 0,01 0,02 0,05 0,1 0,2 

v m/s 

I 

III 


23



Page ................. 4 Basic rating life Page .............. 57 

Temperature 

factor b 2 

Operating Temperature 

temperature factor 

over incl. b 2 

°C – 

– 120 1,0 

120 160 0,9 

Table 

5 

Basic rating life 


requiring maintenance: 

steel-on-steel and steel-onbronze 

For the initial lubrication 

160 180 0,8 

180 – Please contact SKF 

330 

G h = b 1 b 2 b 3 b 4 b 5 ––––– 

p 2,5 v 

The following temperature limits must also be respected 

80 °C For bearings of series GEZ .. ES-2RS 

(polyurethane seals) 

130 °C For all other sealed bearings 

(polyester elastomer seals) 

120 °C Upper temperature limit for standard grease 

and when the product is regularly 

relubricated thereafter 

G hN =G h f β f H 

or 

Sliding factor b 3 

Velocity factor b 4 

Diagram 11 

5 

b 3 

2 

15 

b 4 

10 

1 

10 20 50 100 200 500 

d k mm 

5 

2 

Steel-on-bronze 


1 

0,002 0,005 0,01 0,02 0,05 0,1 

v m/s 

Diagram 12 

G N = 60 f G hN 

where 

G h = rating life for the initial lubrication, 

operating hours 

G hN = basic rating life with regular 

relubrication, operating hours 

G N = basic rating life with regular 

relubrication, number of oscillations 

b 1 = load direction factor, 

b 1 = 1 for constant direction 

load 

b 1 = 2 for alternating direction 

load 

b 2 = temperature factor (➔ Table 5 ) 

b 3 = sliding factor (➔ Diagram 11 ) 

b 4 = velocity factor (➔ Diagram 12 ) 

b 5 = factor for angle of oscillation 

(➔ Diagram 13 ), see also 

under “NB.” 

f = frequency of oscillation, min –1 

f β = factor depending on the angle of 

oscillation (➔ Diagram 14 ), see 

also under “NB.” 

f H = factor depending on frequency 

of relubrication (➔ Diagram 15 ) 


(for values of p < 10 N/mm 2 use 

p = 10 N/mm 2 ) 

v = mean sliding velocity, m/s 

If the basic rating life requirement is 

not met, then the relubrication interval 

N (➔ Diagram 15 ) should be shortened, 

or a larger bearing or rod end 

should be chosen. 

24 





Diagram 

13 

Angle of oscillation 

factor b 5 

10 

b 5 

β° 

5 

2 

2 

I 

1 

5 10 20 45 

If ß < 5°, the value of b 5 for ß = 5° should be used 

6 

Diagram 

14 

Multiplication 

factor f β 

5 

4 

3 

I 

NB. 


bearings having an outside diameter 

of 150 mm and above are 

produced as standard with the 

multi-groove feature in the outer 

ring (➔ page 6). The extra large 

grease reservoir in the bearing 

made possible by the multi-groove 

system is advantageous, particularly 

where the load is of constant 

direction, and enables the relubrication 

interval to be extended, and 

also the service life. 

These advantages are considered 

in the calculation of the basic 

rating life by the coloured regions 

in Diagrams 13 and 14 for the 

factors for the angle of oscillation 

b 5 and f β . Values of these two factors 

up to the upper limit of the 

coloured area may be used for 

bearings with the multi-groove 

system. 

fH 

6 

5 

4 

3 

2 

1 

f β 

2 

1 

5 10 15 20 

β° 

If β < 5°, half the value of f β for β = 5° should be used 

Diagram 15 

0 

1 10 20 30 40 50 

H 

The frequency of relubrication H is defined as the ratio of the basic rating life G h to 

the relubrication interval N (in h), i.e. H = G h /N; if H < 5, the values indicated by the 

broken line can be used 

Relubrication 

factor f H 


25




Load direction 

factor b 1 for 

sliding contact 


steel/sinter 

bronze composite 

Temperature 




steel/sinter 


Type of load Factor Permissible 

b 1 specific 

bearing load 1) 

– – N/mm 2 

Constant load 2) 

Single direction 1 – 

Variable load 

Alternating direction or pulsating 

magnitude at a frequency 

up 0,5 Hz 0,4 40 to 60 

over 0,5 up to 5 Hz 0,2 25 to 40 

1,0 

b 2 

0,8 

Table 

1) 

Inertia forces should also be taken into consideration 

2) 

For constant load, oscillating frequencies above 300 min –1 and very short sliding 

distances, b 1 = 1 can no longer be used because of possible material fatigue; 

please contact SKF for guidance 

6 

Diagram 16 

Maintenance-free sliding 

contact surface combination 

steel/sinter bronze composite 

1 400 

G h =b 1 b 2 ––––– 

p 1,3 v 

or 

G = 60 f G h 

where 

G = basic rating life, number of oscillations 

G h= basic rating life, operating hours 

b 1 = load direction factor 

(➔ Table 6 ) 

b 2 = temperature factor (➔ Diagram 

16 ) 




0,6 

0,4 

0,2 

0 

20 40 60 80 100 120 140 160 

t °C 

NB. 

Calculation of the rating life considers 

the influence of the load and 

sliding velocity. Under very light 

loads and/or low sliding velocities, 

the equations will give relatively 

long service lives. However, the 

influence of environmental factors 

such as contamination, damp or 

moisture and corrosion increases 

in importance the longer the life so 

that deviations from the calculated 

life occur and in many cases the 

calculated life will not be attained. 

26 







steel/PTFE fabric 

Type of load Specific load factor b 1 

– N/mm 2 – 

Table 

7 


factor b 1 for sliding 

contact surface 

combination 


K p 

G h =b 1 b 2 b 4 ––––– 

p n v 

Constant, 

single direction up to 300 1 

2 

where 

G h = basic rating life, operating hours 

b 1 = load direction factor 

(➔ Table 7 ) 

b 2 = temperature factor 


b 4 = velocity factor 



K p = a constant for the specific bearing 

load (➔ Table 8 ) 

n = an exponent for the specific 

bearing load (➔ Table 8 ) 


Varying loads 

(alternating, pulsating) 

at load frequencies 

up to 0,5 Hz up to 50 0,55 

50 to 100 0,4 

over 0,5 to 1 Hz up to 50 0,35 

50 to 100 0,15 

over 1 to 5 HZ up to 50 0,1 

1,0 

b2 

0,8 

Diagram 

17 

Temperature 

factor b 2 for sliding 


combination 


0,6 

0,4 

0,2 

0 

20 40 60 80 100 120 140 160 

t °C 

Table 

Specific bearing load Constant Exponent 

K p 

n 

over incl. 

8 

Constant K p and 

exponent n for sliding 


combination 


N/mm 2 – – 

NB. 

Calculation of the rating life considers 

the influence of the load and 

sliding velocity. Under very light 

loads and/or low sliding velocities, 

the equations will give relatively 

long service lives. However, the 

influence of environmental factors 

such as contamination, damp or 

moisture and corrosion increases 

in importance the longer the life so 

that deviations from the calculated 


calculated life will not be attained. 

25 770 0,2 

25 90 4 000 0,7 

90 300 40 000 1,2 


27




Velocity factor b 4 

Diagram 

18 

b 4 

1,0 

0,9 

0,8 

20* 

2 

5* N/mm 

0,7 

0,6 

0,5 

0,4 

40* 

60* 

80* 

100* 

0,3 

0,2 

0,1 

0,0 

0,001 0,005 0,01 0,05 0,1 

0,5 1 

v, m/s 

b 4 

0,50 

0,45 

0,40 

0,35 

0,30 

0,25 

0,20 

0,15 

0,10 

0,05 

100* 

120* 

140* 

160* 

180* 

200* 

220* 

240* 

260* 

280* 

300* 

0,00 

0,001 0,005 0,01 0,05 0,1 

v, m/s 

*) Specific bearing load 

28 







steel/PTFE composite 

K M 

G h =b 1 b 2 b 3 ––– 

pv 

or 

G = 60 f G h 

where 

G = basic rating life, number of oscillations 

G h = basic rating life, operating hours 

b 1 = load direction factor (➔ Table 9 ) 

b 2 = temperature factor (➔ Diagram 

19 ) 

b 3 = sliding factor (➔ Table 10 ) 

K M = material constant (➔ Table 10) 




Type of load Factor Permissible 

b 1 specific 

bearing load 1) 

– – N/mm 2 

Constant load 2) 

Single direction 1 – 

Variable load 

Alternating direction or pulsating 

magnitude at a frequency 

up to 0,5 Hz 0,25 25 to 40 

over 0,5 up to 5 Hz 0,1 15 to 25 

1,0 

b2 

0,8 

Table 

1) Inertia forces should also be taken into consideration. 

2) For constant load, oscillating frequencies above 300 min –1 and very short sliding 

distances, b 1 = 1 can no longer be used because of possible material fatigue; 

please contact SKF for guidance 

9 

Diagram 19 





steel/PTFE 

composite 

Temperature 




steel/PTFE 

composite 

2 

0,6 

0,4 

0,2 

0 

20 40 60 80 100 

t °C 

NB. 

1.The basic rating life calculated 

using the above equation can 

be doubled by initial lubrication 

together with occasional relubrication, 

see under “Lubrication 

and maintenance”. 

2. Calculation of the rating life considers 

the influence of the load 

and sliding velocity. Under very 

light loads and/or low sliding velocities, 

the equations will give 

relatively long service lives. However, 

the influence of environmental 

factors such as contamination, 

damp or moisture and 

corrosion increases in importance 

the longer the life so that 

deviations from the calculated 


calculated life will not be 

attained. 

Bearing type Bore diameter Sliding Constant 

Series d factor 

Nominal b 3 K M 

over incl. 

– mm – – 

Radial bearings 

GEP .. FS – 180 1 1 055 

180 440 1,15 1 055 

440 – 1,35 1 055 

GEC .. FSA – 440 1 1 055 

440 – 1,15 1 055 

Angular contact bearings 1) 

GAC .. F – 60 1 480 

60 – 1,5 480 

Thrust bearings 

GX .. F – 60 1 670 

60 – 1,5 670 

Rod ends 1 530 

1) For preloaded bearings which cannot be re-adjusted, b 3 always = 1 

Table 

10 

Sliding factor b 3 

and constant K M 

for sliding contact 


steel/PTFE 

composite 


29




Calculation examples 

Variable load and 

sliding velocity 

If, during operation, the load and/or the 

sliding velocity change it is first necessary 

to calculate individual rating lives 

for the periods of constant load and 

sliding velocity, before the basic rating 

life can be calculated. If the load and 

sliding velocity occur as shown by (a) 

in fig 12 the individual basic rating life 

can be calculated using the constant 

values of p and v. However, when the 

load and sliding velocity are not constant 

(b) in fig 12 , it is first necessary 

to calculate the basic rating life for the 

individual time periods using mean 

values of the load and the sliding velocity 

for the individual time periods. 

When this has been done, the total 

basic rating life can be calculated 

using the following equation 

1 

G h = ––––––––––––––––––––––– 

t 1 t 2 t 3 

––––– + ––––– + ––––– +… 

T G h1 T G h2 T G h3 

where 

G h 

= total basic rating life, operating 

hours 

t 1 , t 2 …= time during which 

p 1 and v 1 , p 2 and v 2 etc. 

pertain, h 

T 

= total duration of one cycle 

(= t 1 + t 2 + t 3 + …), h 

G h1 … = individual values of rating life 

for conditions p 1 and v 1 , p 2 

and v 2 etc., operating hours 

Calculation examples 

The calculation examples shown in 

the following serve to illustrate the 

methods used to calculate the requisite 

bearing size or the basic rating life 

for spherical plain bearings and rod 

ends. 

Using the SKF Interactive Engineering 

Catalogue which incorporates 

programs to do these and many other 

calculations, results will be obtained 

quickly and accurately. Additionally, the 

programs can be run any number of 

times to enable the best possible solution 

to be obtained. 

The SKF Interactive Engineering 

Catalogue is available on CD-ROM or 

online at www.skf.com. 

Alternating load and variable sliding velocity 

Fig 12 

v 

p 

p1 

v1 

v 

p 

p1 

v 2 

v1 

v3 

p 2 

p 3 p4 

v 2 

v 3 v4 

p 2 

p 3 

a 

t1 

t2 

t3 

t4 

T 

t 

b 

t1 

t2 

t3 

T 

t 

30 




Page ................ 4 Calculation examples Page .............. 57 

Example 1 

The torque support of a concrete 

transporter 

Bearing GE 25 ES having C = 48 kN 

and d k = 35,5 mm is chosen. The values 

for the specific bearing load 

Given: 

Purely radial load (alternating direction): 

F r = 12 kN 

Half angle of oscillation: β = 15° 

(➔ fig 3 , page 16) 

Frequency of oscillation: f = 10 min –1 

maximum operating temperature: +80 °C 

Requirement: 

A bearing which has a basic rating life 

of 7 000 h. 

As the load is alternating, a steel-onsteel 

spherical plain bearing is the 

appropriate choice. The intention is to 

relubricate the bearing after each 40 

hours of operation. 

If, for the first check, a guideline 

value of 2 is used for the load ratio C/P 

(➔ Table 3 , page 21), the required 

basic dynamic load rating C for the 

bearing is 

C = 2 P = 24 kN 

b 1 = 2 (alternating direction load) 

b 2 = 1 (operating temperature




Example 2 

The attachment of a shock absorber 

of an off-highway vehicle 

Given: 

Radial load: F r = 7 kN 

Axial load: F a = 0,7 kN 


(fig 3 , page 16) 


Load frequency: 2–5 Hz 

Maximum operating temperature: 

+75 °C 

Required: 

A bearing which will have a basic rating 

life corresponding to a driven distance 

of 100 000 km at an average 

speed of 65 km/h without maintenance. 

For design reasons, spherical plain 

bearing GE 20 C with the sliding contact 

surface combination steel/sinter 

bronze composite is proposed. From 

the bearing table, page 76, the basic 

dynamic load rating C = 31,5 kN and 

the sphere diameter d k = 29 mm. 

First the equivalent dynamic bearing 

load must be determined 

F a /F r = 0,7/7 = 0,1 

which gives factor y = 1,4 from 

Diagram 2 , page 19. The equivalent 

dynamic bearing load is thus 

P = y F r = 1,4 × 7 = 9,8 kN 

A first check of bearing size using the 

pv diagram 7 , page 22, shows that 

the values for the specific bearing load 

(K = 100 from Table 4 , page 21) 

P 9,8 

p = K –– = 100 × ––––– = 31 N/mm 2 

C 31,5 

and the sliding velocity (d m = d k = 

29 mm) 

v = 5,82 × 10 –7 d m β f 

= 5,82 × 10 –7 × 29 × 8 × 15 

= 0,002 m/s 

so that this lies in the permissible operating 

range I of the pv diagram. Using 

b 1 = 0,2 (from Table 6 , page 26, for 

a load frequency over 0,5 Hz and 

25 

b 2 = 1 (from Diagram 16 , page 26, 

for temperatures < 80 °C) 

the basic rating life for bearing GE 20 C 

with the sliding contact surface combination 


is 

1 400 

G h =b 1 b 2 –––––– 

p 1,3 v 

1 400 

= 0,2 × 1 × ––––––––––– 

31 1,3 × 0,002 

≈ 1 600 h 

This basic rating life corresponds to a 

distance (at an average speed of 

65 km/h) of 1 600 × 65 = 104 000 km. 

Example 3 

The 320-bar hydraulic cylinder of 

a fully automatic press for building 

industry waste 

Given: 

Radial load (constant direction): 

Operation Load, F r Time 

case 

period, t 

I 300 kN 10 % 

II 180 kN 40 % 

III 120 kN 50 % 

The number of press cycles n = 30 per 

hour, and the movement between the 

end positions (90°) is made in 10 seconds. 

The operating temperature is 

less than +50 °C. 

Required: 

A maintenance-free spherical plain 

bearing with the sliding contact surface 

combination steel/PTFE fabric for 

a rating life of 5 years for 70 h of operation 

per week. 

Using a guideline value for the load 

ratio C/P = 2 (➔ Table 3 , page 21), 

and with P = F rI the required basic 

dynamic load rating 

C = 2 P = 2 × 300 = 600 kN 

From the product table, page 78, bearing 

GE 60 TXE-2LS has a basic dynamic 

load rating C = 695 kN and a 

sphere diameter d k = d m = 80 mm is 

chosen (➔ page 21). 

First it is necessary to check that the 

operation cases I to III fall within the 

permissible range of the pv diagram 

8 , page 23. 

The sliding velocity is the same for 

all three cases. The angle of oscillation 

is specified as 2β, the time t as the 

time taken to pass through 2β in seconds. 

Complete cycle duration is 4β 

(➔ pages 16 and 21). 

2β 

v = 8,73 × 10 –6 × d m ––– 

t 

90 

= 8,73 × 10 –6 × 80 × ––– 

10 

= 0,0063 m/s 

32 





b 4 = (from Diagram 18 , page 28) 

b 4 I = 0,31 

b 4 II = 0,48 

b 4 III = 0,57 

K p = (from Table 8 , page 27) 

K p I = 40 000 

K p II = 4 000 

K p III = 4 000 

n = (from Table 8 , page 27) 

n 1 = 1,2 

n 2 = 0,7 

n 3 = 0,7 

for case I 

The required 5 years of rating life leads 

with the mentioned 70 h/week, 30 cycles/hour 

and assumed 50 weeks per 

year, to 525 000 cycles or 2 920 h. 

(Note that time for a complete cycle is 

20 s.) 

G N, Req = 5 × 70 × 30 × 50 

= 525 000 cycles 

G h, Req = (525 000 × 20)/3 600 

= 2 916 h 

2 

The specific bearing load, p = K(P/C), 

using K = 300 from Table 4 , page 

21, is 

for case I 

P 300 

p I = K –– = 300 × –––– ≈ 129,5 N/mm 2 

C 695 

for case II 

P 180 

p II = K –– = 300 × –––– ≈ 77,7 N/mm 2 

C 695 

for case III 

P 120 

p III = K –– = 300 × –––– ≈ 51,8 N/mm 2 

C 695 

The values for p I , p II , p III and v are 

within the permissible range I of the 

pv diagram 8 , page 23. 

To make the lifetime estimation for 

variable loads and/or sliding velocities 

the calculation of each load case has 

to be made separately, with the equation 

for TX bearings first: 

k p 

G h = b 1 b 2 b 4 –––– 

p n v 

The parameters b 1 , b 2 , b 4 , k p and n 

are defined on page 27 and are as 

below 

b 1 = 1 (from Table 7 , page 27, constant 

load) 

b 2 = 1 (from Diagram 17 , page 27, 

operating temperature < +50 °C) 

40 000 

G hI =1× 1 × 0,31 × ––––––––––––––– 

129,5 1,2 × 0,0063 

≈ 5 746 h 

for case II 

4 000 

G hII =1× 1 × 0,48 × ––––––––––––––– 

77,7 0,7 × 0,0063 

≈ 14 477 h 

for case III 

4 000 

G hIII =1× 1 × 0,57 × ––––––––––––––– 

51,8 0,7 × 0,0063 

≈ 22 833 h 

Using the calculated basic rating lives 

of the three operation cases, the total 

basic rating life for continuous operation 

is (➔ page 30) 

1 

G h = –––––––––––––––––––––– 

t I t II t III 

––––– + ––––– + ––––– 

T G hI T G hII T G hIII 

For t I , t II etc. the percentages given in 

the operating data are inserted and for 

T = t I + t II + t III = 100 %. 

1 

G h = –––––––––––––––––––––––––––––––– 

10 40 50 

–––––––– + ––––––––– + ––––––––– 

100×5 746 100×14 477 100×22 833 

≈ 14 940 h 


33




Example 4 

The linkages of a conveyor 

installation 

Given: 

Radial load of alternating direction: 

F r = 5,5 kN 


(➔ fig 3 , page 16) 


Operating temperature: ≈ +70 °C 

Required: 

A rod end that will provide a basic rating 

life of 9 000 hours under conditions 

of alternating load. 

As the load is alternating, a steel-onsteel 

rod end is appropriate, and it is to 

be relubricated after every 40 hours of 

operation. Using the guideline value for 

the load ratio C/P = 2 from Table 3 , 

page 21, and as P = F r, the requisite 

basic dynamic load rating will be 

C = 2 P = 2 × 5,5 = 11 kN. 

The rod end SI 15 ES with a basic dynamic 

load rating C = 17 kN is selected 

(page 100). The basic static 

load rating C 0 = 37,5 kN and the 

sphere diameter d k = 22 mm. 

The first check of size is made using 

the pv diagram 5 , page 22, and with 

K = 100 (from Table 4 , page 21) 

P 5,5 

p = K –– = 100 × –––– = 32 N/mm 2 

C 17 

and the mean sliding velocity (d m = d k = 

22 mm) 

v = 5,82 × 10 –7 d k β f 

= 5,82 × 10 –7 × 22 × 15 × 25 

= 0,0048 m/s 

p and v both lie within the permissible 

range I of the pv diagram 5 , page 22. 

Checking the permissible load on 

the rod end housing 

C 0 = 37,5 kN 

b 2 = 1 (from Table 5 , page 24, for 

temperatures < 120 °C) 

b 6 = 0,35 (from Table 2 , page 20, for 

rod ends with lubrication hole) 

P perm =C 0 b 2 b 6 

= 37,5 × 1 × 0,35 

= 13,125 kN > P 

The following values of the factors are 

used to determine the basic rating life 

for initial lubrication: 

b 1 = 2 (alternating load) 

b 2 = 1 (for operating temperatures 

< 120 °C, from Table 5 , page 24) 

b 3 = 1,3 (from Diagram 11 , page 24, 

for d k = 22 mm) 


for v = 0,0048 m/s) 


for β = 15°) 

p = 32 N/mm 2 

v = 0,0048 m/s 

Therefore 

330 

G h =b 1 b 2 b 3 b 4 b 5 ––––– 

p 2,5 v 

330 

=2×1×1,3×1,6×3,7× –––––––––––– 

32 2,5 × 0,0048 

≈ 180 operating hours 

The basic rating life for regular relubrication 

(N = 40 h) with 

f β = 5,2 (from Diagram 14 , page 25) 


f H = 2 (from Diagram 15 , page 25, 

for H = G h /N = 180/40 = 4,5) 

G hN = G h f β f H = 180 × 5,2 × 2 

≈ 1 900 operating hours 

The required basic rating life of 9 000 h 

is not achieved by the rod end, so that 

a larger one has to be used. Rod end 

SI 20 ES, with C = 30 kN, C 0 = 57 kN 

and d k = 29 mm is selected and the 

calculation repeated. 

The values for the specific bearing 

load 

5,5 

p = 100 × –––– ≈ 18 N/mm 2 

30 

and the mean sliding velocity (d m = d k 

= 29 mm) 

v = 5,82×10 –7 ×29×15×25 = 0,0063 m/s 

both lie within the permissible range I. 

It is not necessary to check the permissible 

rod end housing load since the 

basic static load rating of the larger 

rod end is higher. Also, as before 

b 1 = 2, b 2 = 1 and b 5 = 3,7 

whilst 


for d k = 29 mm) 


for v = 0,0063 m/s) 

so that 

330 

G h = 2 ×1×1,4×1,8×3,7× ––––––––––– 

18 2,5 × 0,0063 

≈ 710 operating hours 

With f β = 5,2 (from Diagram 14 , page 

25) and f H = 3,7 (from Diagram 15 , 

page 25, for H = 710/40 ≈ 18) the 

basic rating life for regular relubrication 

(N = 40 h) becomes 

G hN = 710 × 5,2 × 3,7 

≈ 13 600 operating hours 

Thus the larger rod end meets the 

rating life requirements. 

34 




Page ................ 4 Friction Page .............. 57 

Friction 

2 

The friction in a spherical plain bearing 

or rod end is primarily dependent on 

the sliding contact surface combination, 

the load and the sliding velocity. 

Because there are so many influencing 

factors which are not mutually independent 

it is not possible to quote 

exact values for the coefficient of friction. 

Under laboratory conditions, however, 

it is possible to record typical developments 

of the coefficient of friction 

for different sliding contact surface 

combinations. The friction during the 

running-in phase is higher than the 

value recorded during the subsequent 

test period. For example, for regularly 

relubricated steel-on-steel spherical 

plain bearings when a suitable highly 

viscous lubricant is used (e.g. the SKF 

grease LGHB 2). Guideline values for 

the coefficient of friction µ will be found 

in Table 1 . They have been determined 

in laboratory trials. 

The coefficient of friction for the 

maintenance-free sliding contact surface 

combinations steel/PTFE fabric 

and steel/sinter bronze composite decrease 

with increasing specific load. 

At a constant specific load, friction will 

be reduced to the given minimum value 

as soon as the transfer of PTFE from 

the sliding layer to the opposing steel 

surface has been completed. The friction 

torque for a spherical plain bearing 

or rod end can be calculated using 

M = 0,5 × 10 –6 µP d m 

where 

M = friction torque, Nm 

µ = coefficient of friction 

(➔ Table 1 ) 

P 

= equivalent dynamic bearing load, 

kN 

d m = mean bearing diameter, mm, for 

radial spherical plain bearings 

d m =d k for radial spherical plain 


d m = 0,9 d k for angular contact 


d m = 0,7 d k for spherical plain 


As operation progresses and as a 

result of negative influences (contamination, 

inadequate lubrication), even 

under very light loads, the maximum 

values of the coefficient of friction 

quoted in the table may be approached 

or even exceeded if conditions are particularly 

unfavourable. In applications 

where friction is especially important, 

therefore, it is recommended that the 

maximum values of the coefficient of 

friction be used when determining the 

required power rating, for security 

reasons. For all bearings, which are 

operated under conditions of mixed or 

dry friction, there may be small differences 

between adhesive and sliding 

friction. Operation which is entirely 

free of stick-slip cannot be achieved. 

Experience has shown that stick-slip 

effects occur when the surrounding 

construction is “soft”. In most applications, 

however, the effects are negligible. 

Table 

Sliding contact surface Coefficient of friction 

combination µ 

1 

min 

max 

Steel-on-steel 0,08 0,20 

Steel-on-bronze 0,10 0,25 

Steel/sinter bronze composite 0,05 0,25 

Steel/PTFE fabric 0,03 0,15 

Steel/PTFE composite 0,05 0,20 

Coefficients 

of friction for 

different sliding 


combinations 

(guideline values) 


35



Page ................ 4 Radial location Page .............. 57 

Application of bearings 

Radial location of 


The inner and outer rings of spherical 

plain bearings must be radially secured 

(located) to the shaft and in the 

housing so that the sliding movements 

take place, as intended, in the bearing. 

Otherwise the rings may begin to creep 

or wander in or on their seatings in the 

circumferential direction under load. 

Successful radial location is only 

usually achieved by using fits with sufficient 

interference. However, an interference 

fit cannot always be applied, 

e.g. if easy mounting and dismounting 

are desired, or if the bearing must be 

able to be displaced axially without 

restraint. 

The appropriate fits are always determined 

by the operating conditions. 

1. Type and magnitude of the load 

The degree of interference must suit 

the type and magnitude of the load, 

i.e. the heavier the load, and the higher 

the shock content, the heavier the 

interference required (➔ fig 1 ). 

• Under heavy loads, spherical plain 

bearings will deform elastically which 

may lead to a loosening of the fit and 

creeping of the ring on/in its seating. 

• The strength of the associated components 

must be adequate to take 

up the loads and fully support the 

bearing. 

• If the associated components deform, 

there is a risk that hardened bearing 

rings will break. 

• Steel-on-steel spherical plain bearings 

require tighter fits than the maintenance-free 

bearings which have 

lower friction. 

2. Bearing internal clearance 

An interference fit will cause the 

• inner ring to expand elastically, and 

the 

• outer ring to be compressed elastically. 

This reduces the original internal clearance 

in the bearing to the so-called 

operating clearance (➔ fig 2 ). The 

clearance also depends on load and 

temperature. 

The original internal clearance differs 

depending on the type and size of 

the bearing and has been selected so 

that if the recommended tolerances for 

the shaft and housing seatings are applied, 

an appropriate operational clearance 

(or preload) will be left in the bearing 

under normal operating conditions. 

If interference fits are used for both 

bearing rings, or if the temperature conditions 

are unusual, it may be necessary 

to use a larger initial internal clearance 

than “Normal” for steel-on-steel 

bearings. 

Relationship between load and requisite interference 

Operating clearance 

Fig 

1 

Fig 

2 

Bearing 

internal 

clearance 

Operating 

clearance 

36 


GE 



Page ................ 4 Radial location Page .............. 57 

3. Temperature conditions 

In operation, the bearing rings will normally 

have a higher temperature than 

their seatings. This means that 

• the fit of the inner ring will loosen 

(➔ fig 3 ) and 

• the fit of the outer ring will become 

tighter, which may restrict any required 

axial displacement in the 

housing. 

If there is a considerable temperature 

difference between inner and outer 

rings there will be a change in the operating 

clearance which must be considered 

when selecting the fits, so 

that a blockage of the bearing can be 

avoided. 

4. Design of associated components 

The design of the components providing 

the bearing seatings should not 

lead to irregular deformation (out-ofround) 

of the bearing (➔ fig 4 ). 

• Split housings are not suitable for 

interference fits. 

• Thin-walled housings, light alloy housings 

and hollow shafts all call for a 

tighter fit to be used than for thickwalled 

steel or cast iron housings and 

solid shafts – and must have sufficient 

strength. 

• Heavy loads and interference fits call 

for thick-walled one-piece steel or 

cast iron housings and solid steel 

shafts. 

5. Axial displacement of nonlocating 


A non-locating bearing, which is to provide 

radial support only, must always 

be able to be displaced axially (➔ fig 

5 ). This is normally achieved by selecting 

a loose fit for one of the bearing 

rings, generally the inner ring of spherical 

plain bearings. The reasons are 

• the shaft seating can be easily and 

economically hardened and ground; 

this facilitates axial displacement. 

The hardness should be at least 

50 HRC and the surface roughness 

R z should be ≤ 10 µm. 

• the outer rings of most spherical 

plain bearings are axially fractured at 

one or two positions, or are radially 

split. This can hinder axial displacement 

or make it completely impossible. 

• the housing bore should be protected 

against wear. 

2 

Surface finish of seatings 

The recommended surface roughness 

to ISO 4288:1996 for the bearing seatings 

is 

• for shaft seatings 

R z ≤ 10 µm 

• for housing bore seatings 

R z ≤ 16 µm 

Change of fit with temperature Out-of-round bearing seating Axial displacement 

Fig 

3 

Fig 4 

Fig 5 


30-2RS 

LH 


37



Page ................ 4 Tolerances Page .............. 57 

Operating conditions 

Tolerance 

Sliding contact surface combination 

steel-on-steel maintenance-free 


Loads of all kinds m6 (n6) 1) k6 

interference fit 

Loads of all kinds h6 h6 or g6 

clearance or (hardened (hardened 

transition fit shaft) shaft) 

Angular contact bearings 

Loads of all kinds m6 (n6) m6 



Loads of all kinds m6 (n6) m6 


Table 

The tolerances given in brackets may be chosen for very heavily loaded bearings. If chosen, it is necessary to check 

that the residual operating clearance is sufficient for correct performance of the bearing or whether a bearing with 

larger clearance must be used 

1) These recommendations do not apply to bearings of series GEG which have a bore diameter tolerance to H7 and 

are normally mounted on shaft seatings machined to m7. If, for mounting reasons the shaft is machined to tolerance 

f7, it should be hardened as relative movements of the shaft with respect to the bearing bore will take place 

and wear may result 

Shaft fits 

Housing fits 

1 

Recommended fits 

Only a limited number of ISO tolerance 

grades are appropriate to spherical 

plain bearings. Fig 6 shows schematically 

the relative positions of these in 

relation to the bore and outside diameters 

of the bearings. The recommended 

tolerances for 

• the shaft seating are given in Table 

1 , and 

• the housing bore in Table 2 . 

These recommendations are based on 

the considerations described above 

and have been confirmed in a wide 

variety of bearing applications.The ISO 

tolerance limits are given in 

• Table 

• Table 

3 for shafts, and 

4 for housing bores. 

To facilitate the calculation of the minimum 

and maximum values of the theoretical 

interference or clearance, the 

standardized bearing bore diameter deviations 

(∆ dmp ) and the bearing outside 

diameter deviations (∆ Dmp ) are given in 

the tables. 

Operating conditions 

Table 

Tolerance 


steel-on-steel maintenance-free 

2 


Light loads, H7 H7 

axial displacement required 

Heavy loads M7 (N7) K7 

Light alloy housings N7 M7 

Angular contact bearings 

Loads of all kinds, M7 (N7) M7 


Loads of all kinds, J7 J7 

can generally be displaced axially 


Purely axial loads H11 H11 

Combined loads J7 J7 

ISO shaft and housing tolerances 

H11 

Fig 

6 

+ 

0 

H7 J7 K7 M7 N7 

+ 

0 

g6 h6 k6 m6 n6 

The tolerances given in brackets may be chosen for very heavily loaded bearings. If chosen, it is necessary to 

check that the residual operating clearance of radial bearings is sufficient for correct performance of the bearing or 

whether a bearing with larger clearance must be used 

38 




Page ................ 4 Tolerances Page .............. 57 

Shaft Bearing Shaft diameter tolerances 

Diameter Bore 

diameter 

∆ dmp g6 h6 k6 m6 n6 

Nominal 

Deviations 

over incl. min max high low high low high low high low high low 

mm µm µm 

Table 

3 

2 

3 6 –8 0 –4 –12 0 –8 +9 +1 +12 +4 +16 +8 

6 10 –8 0 –5 –14 0 –9 +10 +1 +15 +6 +19 +10 

10 18 –8 0 –6 –17 0 –11 +12 +1 +18 +7 +23 +12 

18 30 –10 0 –7 –20 0 –13 +15 +2 +21 +8 +28 +15 

30 50 –12 0 –9 –25 0 –16 +18 +2 +25 +9 +33 +17 

50 80 –15 0 –10 –29 0 –19 +21 +2 +30 +11 +39 +20 

80 120 –20 0 –12 –34 0 –22 +25 +3 +35 +13 +45 +23 

120 180 –25 0 –14 –39 0 –25 +28 +3 +40 +15 +52 +27 

180 250 –30 0 –15 –44 0 –29 +33 +4 +46 +17 +60 +31 

250 315 –35 0 –17 –49 0 –32 +36 +4 +52 +20 +66 +34 

315 400 –40 0 –18 –54 0 –36 +40 +4 +57 +21 +73 +37 

400 500 –45 0 –20 –60 0 –40 +45 +5 +63 +23 +80 +40 

500 630 –50 0 –22 –66 0 –44 +44 0 +70 +26 +88 +44 

630 800 –75 0 –24 –74 0 –50 +50 0 +80 +30 +100 +50 

800 1 000 –100 0 –26 –82 0 –56 +56 0 +90 +34 +112 +56 

1 000 1 250 –125 0 –28 –94 0 –66 +66 0 +106 +40 +132 +66 

ISO shaft limits 

ISO housing limits 

Table 

Housing Bearing Housing bore tolerances 

Bore 

Outside 

diameter diameter 

∆ Dmp H11 H7 J7 K7 M7 N7 

Nominal 

Deviations 

over incl. max min low high low high low high low high low high low high 

4 

mm µm µm 

10 18 0 –8 0 +110 0 +18 –8 +10 –12 +6 –18 0 –23 –5 

18 30 0 –9 0 +130 0 +21 –9 +12 –15 +6 –21 0 –28 –7 

30 50 0 –11 0 +160 0 +25 –11 +14 –18 +7 –25 0 –33 –8 

50 80 0 –13 0 +190 0 +30 –12 +18 –21 +9 –30 0 –39 –9 

80 120 0 –15 0 +220 0 +35 –13 +22 –25 +10 –35 0 –45 –10 

120 150 0 –18 0 +250 0 +40 –14 +26 –28 +12 –40 0 –52 –12 

150 180 0 –25 0 +250 0 +40 –14 +26 –28 +12 –40 0 –52 –12 

180 250 0 –30 0 +290 0 +46 –16 +30 –33 +13 –46 0 –60 –14 

250 315 0 –35 0 +320 0 +52 –16 +36 –36 +16 –52 0 –66 –14 

315 400 0 –40 0 +360 0 +57 –18 +39 –40 +17 –57 0 –73 –16 

400 500 0 –45 0 +400 0 +63 –20 +43 –45 +18 –63 0 –80 –17 

500 630 0 –50 0 +440 0 +70 – – –70 0 –96 –26 –114 –44 

630 800 0 –75 0 +500 0 +80 – – –80 0 –110 –30 –130 –50 

800 1 000 0 –100 0 +560 0 +90 – – –90 0 –124 –34 –146 –56 

1 000 1 250 0 –125 0 +660 0 +105 – – –105 0 –145 –40 –171 –66 

1 250 1 600 0 –160 0 +780 0 +125 – – –125 0 –173 –48 –203 –78 

1 600 2 000 0 –200 0 +920 0 +150 – – –150 0 –208 –58 –242 –92 


39



Page ................ 4 Axial location Page .............. 57 

Axial location of 


An interference fit is not sufficient to 

axially locate a bearing ring. Normally a 

suitable axial securement is required. 

The bearing rings of a locating bearing 

should be axially located on both 

sides. The bearing rings generally 

have an interference fit and are usually 

supported on one side by a shaft or 

housing shoulder. Inner rings are axially 

secured on the side opposite the 

shoulder by 

Fig 7 

Fig 8 

• a plate screwed to the shaft end 

(➔ fig 7 ), or 

• a spacer sleeve between the ring and 

a neighbouring machine component 

(➔ fig 8 ). 

Outer rings are generally retained by 

the cover of the housing bore (➔ fig 

7 ). 

For non-locating bearings the outer 

ring (which normally has a tight fit) 

should be axially located; the inner ring 

must be free to move axially on the 

shaft (➔ fig 5 , page 37). 

It should be observed that with bearings 

of series GEP (➔ fig 9 ), which 

have a radially split outer ring, expansion 

forces will be produced under 

purely radial load; the axial components 

of these forces will act on the 

housing cover. The axial load acting on 

the cover may be as much as 30 % of 

the radial load. This must be taken into 

account when dimensioning the housing 

cover and selecting the size and 

number of the attachment screws. 

If shaft and/or housing shoulders are 

undesirable because of manufacturing 

or assembly considerations, spacer 

sleeves or rings can be inserted between 

the bearing ring which is to be 

located and an adjacent machine component 

(➔ fig 10 and 11 ). 

The axial location of non-separable 

bearings using retaining rings (➔ fig 

10 and 11 ) saves space and permits 

quick mounting and dismounting, as 

well as simplifying the machining of 

seatings. If larger axial forces have 

to be accommodated, a support ring 

(➔ fig 11 ) should be arranged between 

the bearing ring and the retaining ring, 

so that the retaining ring is not subjected 

to excessive bending moments. 

Using an end plate and cover to locate 

a bearing 

For bearing location, the retaining 

rings used usually have constant radial 

width (also known as snap rings) to 

DIN 471:1981 or DIN 472:1981. 

Locating a radially split bearing 

Using a spacer sleeve and cover to 

locate a bearing 

Fig 

9 

40 




Page ................ 4 Abutment and fillet dimensions Page .............. 57 

Fig 

10 

Fig 

11 

Abutment and fillet dimensions 

The abutment and fillet dimensions 

should be such that 

• a sufficiently large support surface is 

available for the bearing ring, 

• moving parts of the bearing arrangement 

cannot foul stationary components, 


• the fillet radius should be smaller 

than the chamfer of the bearing. 

2 

Locating a bearing using snap rings in 

the housing and adjacent components 

on the shaft 

Locating a bearing using adjacent components 

in the housing and a retainer 

ring on the shaft 

Appropriate abutment dimensions 

(➔ fig 12 ) are given for each bearing 

in the product tables. The transition 

from the bearing seating to the shaft or 

housing shoulder may be designed 

either as a fillet (➔ fig 13 ) or an 

undercut (➔ fig 14 ). 

Recommended abutment and fillet 

dimensions 

Fillet dimensions for shaft and housing 

shoulders 

Undercut dimensions for shaft and 

housing shoulders 

Da 

r a 

rb 

da 

Fig 

12 

r bmax 

r 2min 

r 2min 

r amax 

r 1min 

Fig 

r 1min 

13 

ha 

ba 

rs 

rc 

h a 

14 

r s 

r c 

r s 

r s 

b a 

Fig 


41



Page ................ 4 Fillets Page .............. 57 

Fillets 

Suitable dimensions for the fillet are 

given in the product tables and for the 

undercut in Table 5 . The stress conditions 

in a stepped shaft are more 

favourable, the larger the fillet (rounding) 

of the transition to the shaft 

shoulder. 


The inner rings of rod ends can, in the 

same way as bearings, be axially located 

by a shaft shoulder, a nut or a 

retaining ring. 

Rod ends mounted on threaded 

rods or in extension tubes should be 

prevented from coming loose by an 

extra nut on the rod or the external 

thread of the rod end shank. The nut 

should be securely tightened against 

the support surface on the rod end 

housing or on the tube (➔ fig 15 ). 

Relieved fillets 

Attachment of rod ends 

Chamfer Fillet dimensions 

dimensions 

r 1 , r 2 b a h a r c 

min 

Table 5 

Fig 15 

mm 

mm 

1 2 0,2 1,3 

1,1 2,4 0,3 1,5 

1,5 3,2 0,4 2 

2 4 0,5 2,5 

2,5 4 0,5 2,5 

3 4,7 0,5 3 

4 5,9 0,5 4 

5 7,4 0,6 5 

6 8,6 0,6 6 

7,5 10 0,6 7 

42 




Page ................ 4 Seals Page .............. 57 

Sealing 

Most bearing arrangements must be 

sealed to prevent external contamination 

and damp from entering the bearing. 

The efficiency of the sealing has a 

decisive influence of the service life of 

the bearing. In contrast to most other 

bearing types, which only move in one 

plane, the alignment capabilities of the 

spherical plain bearings place extra 

demands on the sealing. 

When selecting appropriate seals, 

many factors have to be considered 

including 

Note 

Further information about radial 

shaft seals, referred to in the table, 

can be found in the SKF catalogue 

4006 “CR seals” or the “SKF Interactive 

Engineering Catalogue” on 

CD-ROM or online at www.skf.com. 

Sealing strips can also be supplied 

by SKF in felt (FS strips) or, 

for high temperatures, in aluminium-boron 

silicate material 

(FSB strips). 

CR seals 

2 

• the permissible angle of tilt, 

• the available space, 

• the environmental conditions, 

• the efficiency of the seal, 

• the type of lubrication and the 

frequency of relubrication, and 

• the justifiable cost. 

Depending on the application, one 

or other of the above factors will outweigh 

the others. It is therefore not 

possible to establish general rules for 

sealing design. Table 6 , pages 44 

and 45, gives an overview of the possible 

seals, their design characteristics 

and suitability to meet different 

demands. 


43




Seal Illustration Design characteristics Suitability 

Table 

6 

Integral RS 

design 

Double-lip rubbing seal of 

polyurethane (–20 to +80 °C) or 

polyelastomer (–30 to +130 °C) 

✔ for compact bearing arrangements, 

mainly indoors 

✔ for cramped spaces 

✔ for high sealing demands when combined 

with an outboard seal 

✔ for long service life with minimum 

maintenance 

✔ for bearings which are to rotate 

Integral heavy 

duty LS design 

Triple-lip rubbing seal of elastomer 

with steel backing (–25 to +120 °C) 

✔ for compact bearing arrangements 

✔ for high sealing demands 

✔ for long service life with minimum 

maintenance 

✔ for rotating bearing arrangements 

✔ for difficult operating conditions in the 

presence of sand or mud 

Gap type 

Simple and economic, no wear, 

simple mounting 

✔ for maintenance-free bearings 

✔ for small angles of tilt 

✔ for high temperatures 

✔ for moderately dusty environments 


Gap type with 

grease 

Simple and efficient with periodic 

relubrication 

May pollute environment 

✔ for bearings and rod ends requiring 

maintenance 


✔ for rough conditions in the presence 

of sand, clay, slush etc. 

V-shaped 

(commercially 

available) 

Simple, lightly preloaded seal of 

polyurethane (–40 to +100 °C) 

Good wear strength and resistance to 

grease, oil and other environmental 

influences 

✔ for contaminant exclusion 

✔ for angles of tilt up to 2° 

✔ for bearing arrangements with shafts 

up to 300 mm diameter 


V-Ring 

(commercially 

available) 

Elastic seal which sits on shaft and rotates 

with it, axial sealing lip 

of nitrile rubber (–40 to +100 °C) 

or fluoro rubber (–40 to +200 °C) 

Good wear and chemical resistance 


✔ for maintenance-free and greaselubricated 


✔ for all shaft diameters 

✔ for angles of tilt between 2 and 4° 

depending on size 


Felt 

(commercially 

available) 

Simple to install, good resistance to grease 

(–40 to +100 °C) 

✔ for dust and minor damp exclusion 

✔ for grease retention 

✔ for large angles of tilt 

✔ for all sizes of bearing 


44 





Seal Illustration Design characteristics Suitability 

Table 

6 

Radial shaft 

(commercially 

available) 

Steel reinforced (either externally 

or internally) elastomer with lip 



Good wear resistance, good resistance 

to grease, oil and other environmental 

influences 


✔ for grease retention 

✔ for oil retention 


✔ for all sizes of bearing 


2 

Radial shaft 

with dust lip 

(commercially 

available) 

Steel reinforced (either externally 

or internally) elastomer with lips 





influences 

✔ for strong contaminant exclusion 

✔ for oil retention 


✔ for bearings up to approx. 300 mm 

bore 


O-ring 

(commercially 

available) 

Nitrile rubber (–30 to +100 °C) or 

fluoro rubber (–20 to +200 °C) 

✔ for reliable moisture exclusion 

✔ for oil and grease retention 

✔ for very small angles of tilt 

✔ for slow oscillating movements 

Profiled rubber 

(commercially 

available) 

Polyurethane (–40 to +100 °C) 



influences 

✔ for hermetically sealed bearing 

arrangements 


✔ for slow oscillating movements; 

initial oiling or greasing of faces 

reduces friction 

Profiled rubber 

with clamp and 

lock 

(commercially 

available) 

Elastomer strip (–40 to +100 °C) 



influences 

✔ for hermetically sealed bearing 

arrangements 

✔ for slow oscillating movements 

Initial oiling or greasing of faces 

reduces friction 


Mechanical 

seals 

(commercially 

available) 

Stainless steel rings and cup springs of 

nitrile rubber (–40 to +100 °C) 



influences 


✔ for oil and grease retention 



Spring steel 

washers 

(commercially 

available) 

Labyrinth seals of sets of washers for high 

temperatures. Excellent wear resistance, 

good chemical resistance 


✔ grease exit vents needed in housing 

cover if grease used 




45



Page ................ 4 Design for easy mounting Page .............. 57 

Designing the bearing 

arrangement for easy 

mounting and dismounting 

To ease mounting, the shaft ends and 

housing bores should have a lead-in 

with an angle of between 10 and 20° 

(➔ fig 16 ). This not only eases mounting 

but reduces the risk of damaging 

the mating surfaces by skewing of the 

bearing rings. 

Particularly for large bearings, it is 

necessary to design the arrangement 

so that bearing mounting, and especially 

dismounting, are simplified or 

even made possible. 

To facilitate subsequent removal of 

a bearing, it can be advantageous to 

• provide recesses in the shaft 

shoulder (➔ fig 17 ), and 

• recesses or threaded holes in the 

housing bore (➔ fig 18 ) 

so that withdrawal tools can be used 

without difficulty. 

To dismount maintenance-free bearings 

having a bore diameter of some 

80 mm and above, it is recommended 

that the oil injection method be used. 

This involves introducing oil under high 

pressure between the bearing inner 

ring and its shaft seating. This greatly 

reduces the force required to dismount 

the bearing and practically eliminates 

any risk of damaging the bearing and 

seating. 

In order to employ the oil injection 

method it is necessary to provide an oil 

supply duct in the shaft as well as an 

oil distributor groove in the seating 

(➔ fig 19 ). The distance between this 

groove and the bearing side from which 

mounting and dismounting are to be 

performed should be approximately 

one third of the seating width. Recommended 

dimensions for the ducts and 

grooves as well as for the threads for 

the oil supply connection are given in 

Tables 7 and 8 . 

Chamfering shaft ends and housing 

bore entrances Shaft shoulder with recess Housing shoulder with threaded holes 

Fig 16 

Fig 17 

Fig 18 

46 




Page ................ 4 Design for easy mounting Page .............. 57 

Table 

7 

Table 

8 

L 

L 

3 

G a 

G a 

N 

60° 

Gc 

Gb 

h a 

r a 

b a N a N a 

Gc 

Gb 

2 

Design A 

Design B 

Bearing 

Dimensions 

seating 

diameter b a h a r a N 

over incl. 

Thread Design Dimensions 

1) 

G a G b G c 

N a 

max 

mm 

mm 

– – mm 

100 3 0,5 2,5 2,5 

100 150 4 0,8 3 3 

150 200 4 0,8 3 3 

200 250 5 1 4 4 

250 300 5 1 4 4 

300 400 6 1,25 4,5 5 

400 500 7 1,5 5 5 

500 650 8 1,5 6 6 

650 800 10 2 7 7 

M6 A 10 8 3 

G 1/8 A 12 10 3 

G 1/4 A 15 12 5 

G 3/8 B 15 12 8 

G 1/2 B 18 14 8 

G 3/4 B 20 16 8 

800 1 000 12 2,5 8 8 

Oil ducts and distributor grooves 

Threaded holes for connection 

Fig 

19 

Bearing seating with oil ducts 

and distributor grooves for easy 

dismounting 


47



Page ................ 4 Lubrication Page .............. 57 

Lubrication 




must be maintained and lubricated to 

• reduce friction, 

• reduce wear, 

• extend bearing life, 

• protect against corrosion and 

• prevent contamination by dirt or 

moisture. 

The sliding contact surfaces are phosphated 

and treated with a “running-in” 

lubricant. This special surface treatment 

has a favourable influence on the 

running-in phase. In order to obtain the 

desired rating life the bearings must be 

greased at the very latest before being 

taken into operation and must then be 

regularly relubricated. 

Relubrication of the bearing can only 

be made if the necessary ducts for relubrication 

are provided in the housing 

(➔ fig 1 ) or the shaft (pin) (➔ fig 2 ) 

so that grease can be directly supplied 

to the bearing. To facilitate efficient lubrication 

in service, all SKF steel-on- 

steel spherical plain bearings (with the 

exception of the smallest bearings of 

the E and ESA designs) have an annular 

groove and lubrication holes in both 

inner and outer rings. 

If the arrangement is appropriately 

designed, the bearing can be supplied 

with grease from the side. To compel 

grease to pass through the bearing it is 

necessary to prevent the grease from 

exiting the bearing arrangement from 

the same side as it is supplied and to 

provide a grease exit opening at the 

opposite side (➔ fig 3 ). Where possible, 

the free space surrounding the 

bearing should be filled with grease. 

It is recommended that the SKF 

grease LGHB 2 be used to lubricate 

steel-on-steel spherical plain bearings. 

This is a high-quality calcium sulphonate 

base grease. Its properties include 

• excellent load carrying capacity, 

• very good rust inhibition, 

• very good resistance to ageing, 

• good water resistance, and 

• a wide operating temperature range 

of –20 to +150 °C. 

If operating temperatures are higher 

than this special grease should be used 

instead, and the SKF application engineering 

service should be contacted. 

More information on SKF greases will 

be found in Table 1 . 

Maintenance-free 




and steel/PTFE fabric 

During the first period of operation of 

these bearings, a transfer of PTFE 

takes place from the dry sliding contact 

surface to the opposing surface of the 

inner ring. Any lubrication of the sliding 

contact surfaces would disturb this 

transfer and shorten bearing life. Therefore, 

lubrication of these bearings, or 

rod ends with the same sliding contact 

surface combinations, is not advisable 

and they have no relubrication 

facilities. 

To provide protection against corrosion 

and to enhance sealing, the free 

space surrounding the bearing may, 

Relubricating the bearing via the outer 

ring 

Relubricating the bearing via the inner 

ring 

Relubricating the bearing from the side 

Fig 

1 

Fig 

2 

Fig 

3 

48 





Property 

SKF lubricating greases 

SKF greases (designation) 

LGHB 2 LGMT 3 LGEP 2 LGGB 2 1) 

for sliding contact surface combinations 

steel-on-steel steel-on-bronze steel/PTFE composite 

Thickener Calcium Lithium Lithium Lithium/ 

sulphonate soap soap calcium 

complex soap 

soap 

Base oil Mineral oil Mineral oil Mineral oil Ester oil 

Colour Brown Yellowish Light brown White 

brown 

Operating –20 to +150 –30 to +120 –20 to +110 –40 to +120 

temperature, °C 

(continuous operation) 

Kinematic viscosity 

of base oil, mm2/s 

at +40 °C 400 to 450 120 to 130 200 110 

at +100 °C 26,5 12 16 13 

Consistency 2 3 2 2 

(to NLGI Scale) 

Table 

1) Biologically degradeable grease for use in applications where strict ecological demands must be met and where 

lubrication cannot be dispensed with 

1 



An initial lubrication followed by occasional 

relubrication of steel/PTFE composite 

bearings can extend the service 

life by a factor of at least 2. The inner 

rings and shaft washers of such bearings 

are coated with lithium base 

grease before leaving the factory. 

If operating conditions are such that 

protection against corrosion and enhanced 

sealing are required, the free 

space surrounding the bearing (➔ fig 

5 ) should be filled with the same 

grease as that used for bearing lubrication. 

The appropriate time to replenish 

or renew the grease in the bearing 

arrangement is determined by the operating 

conditions and the ageing of 

the grease. 

Rust inhibiting, water-repellant lithium 

base greases of normal consistency 

should be used, for example, the SKF 

grease LGEP 2 (➔ Table 1 ). On no 

account should greases containing 

molybdenum disulphide or other solid 

lubricants be used. 

2 

however, be filled with grease (➔ fig 

4 ). Rust inhibiting, water-repellant 

lithium base greases of normal consistency 

should be used, for example, 

the SKF greases LGEP 2 or LGMT 3 

(➔ Table 1 ). 

Grease supply to free space in the 

housing surrounding a steel/sinter 

bronze composite bearing 

Grease supply to free space in housing 

surrounding a large steel/PTFE composite 

bearing 

Note 

SKF spherical plain bearings, depending 

on their design are either 

completely or partially coated with 

an oily preservative or filled with 

grease. Skin contact should be 

avoided as these substances may 

give rise to irritation or allergic 

reactions. 

Fig 

4 

Fig 

5 


49




Rod ends requiring 

maintenance 

Rod ends with the sliding contact surface 

combinations steel-on-steel and 

steel-on-bronze require maintenance 

and must be lubricated. To facilitate 

this 

• all SKF steel-on-steel rod ends can 

be relubricated via a lubrication hole 

or grease nipple in the rod end housing 

as well as via the inner ring (➔ 

fig 6 ) with the exception of the 

small-sized rod ends of the E and 

ESA designs; 

• all SKF steel-on-bronze rod ends can 

be relubricated via a lubrication hole 

or grease nipple in the rod end housing 

(➔ fig 7 ). 

The recommendations above for steelon-steel 

spherical plain bearings also 

apply to steel-on-bronze rod ends. 

These recommendations also apply 

to the steel-on-bronze rod ends of the 

SIKAC .. M and SAKAC .. M series 

where SKF grease LGMT 3 is recommended. 

It is, however, also possible 

to use lithium base greases of normal 

consistency without solid lubricant 

additives. 

Maintenance-free rod 

ends 

Rod ends with maintenance-free sliding 

contact surface combinations are 

generally to be used as dry sliding 

bearings, i.e. they should not be lubricated; 

the maintenance-free rod ends 

are without relubrication facilities. 

However, the service life of steel/- 

PTFE composite rod ends can be much 

extended by an initial application of 

grease followed by occasional relubrication. 

The inner ring is already coated 

with a lithium base grease before leaving 

the factory. 

Note 

SKF rod ends, depending on their 

design are either completely or partially 

coated with an oily preservative 

or filled with grease. Skin contact 

should be avoided as these 

substances may give rise to irritation 

or allergic reactions. 

Relubrication facilities for steel-on-steel rod ends 

Relubrication facilities for steel-on-bronze rod ends 

Fig 

6 

Fig 

7 

Lubrication hole Grease nipple Rod end with female thread Rod end with male thread 

50 




Page ................ 4 Maintenance Page .............. 57 

Maintenance 

2 

To obtain a long service life with spherical 

plain bearings and rod ends requiring 

maintenance, they must be relubricated. 

Used grease together with wear 

debris and any contamination should 

be removed from the contact zone and 

be replaced by fresh grease. 

The relubrication interval should be 

determined when performing the bearing 

calculation. The frequency of relubrication 

is of decisive importance for 

the attainable service life and depends 

on many factors including 

• the magnitude of the load, 

• the type of load, 

• the angle of oscillation, 

• the frequency of oscillation, 

• the operating temperature 

• the sealing arrangement and 

• other environmental conditions. 

Long service lives can be attained when 

the following relubrication conditions 

are observed: 

• the same grease is used as originally 

applied; 

• the relubrication should be carried 

out at the operating temperature; 

• the bearing should be relubricated 

before a long interruption in operation 

occurs, e.g. before construction 

machinery or agricultural equipment 

is laid up. 

Relubrication of non-locating 


Non-locating bearings, where axial 

displacement takes place along the 

shaft or pin, should always be relubricated 

via the shaft and bearing inner 

ring (➔ fig 2 , page 46). By supplying 

lubricant in this way grease will also 

enter between the mating surfaces of 

inner ring and shaft seating. This reduces 

friction and consequently the 

axial forces produced when axial displacement 

takes place. 

Storage 


ends are treated with a preservative 

before they are packaged. They can, 

therefore, be stored in their original 

packages for several years. However, 

the relative humidity in the storeroom 

should not exceed 60 %. 

SKF has the correct greases for spherical 

plain bearings and rod ends, including 

the biologically degradable grease 

LGGB 2 


51



Page ................ 4 Mounting Page .............. 57 

Mounting 


Fig 1 

Fig 2 

Skill and cleanliness when mounting 

are necessary if spherical plain bearings 

and rod ends are to perform correctly 

and not fail prematurely. 

The bearings and rod ends should 

only be taken from their packages immediately 

before mounting so that they 

do not become contaminated. Any 

components which have possibly become 

dirty as a result of improper handling 

(damaged packaging etc.) should 

be wiped using a clean cloth. 

The sliding contact surfaces of the 

bearings are matched to provide favourable 

friction and wear characteristics. 

Any alteration of the sliding surfaces 

would shorten the service life, 

therefore, bearings must not be 

washed or come into contact with solvents, 

cleaners, oils or similar media. 

The components associated with 

the bearings (housings, shafts or pins 

etc.) should be cleaned and any burrs 

removed. They should also be checked 

with regard to accuracy of dimensions 

and form before mounting is 

started. 

Plane of fracture or split and main 

direction of load 

When mounting spherical plain bearings 

with a fractured or split outer ring 

it is essential that the joint be positioned 

at right angles to the main direction 

of load (➔ fig 1 ) as otherwise the service 

life will be shortened, particularly 

under heavy loads. 

Mounting with the aid of a dolly 

Simultaneous mounting in housing and 

on shaft 

Mounting using a press 

Never direct blows at the bearing rings 

Fig 

3 

Fig 

4 

Fig 

5 

52 





Mechanical mounting 

The following tools are suitable for 

mounting spherical plain bearings 

• a mounting dolly (➔ fig 2 ) or length 

of tubing; the ring having an interference 

fit should generally be mounted 

first; 

• a dolly having two abutment surfaces 

(➔ fig 3 ) for mounting simultaneously 

on the shaft and in the housing; 

• for larger numbers of bearings, suitable 

tools can be used in combination 

with a press (➔ fig 4 ). 

When mounting spherical plain bearings, 

• on no account should blows be directed 

at the bearing rings (➔ fig 5 ); 

the use of a hammer and drift can 

also easily damage the rings; 

• the mounting force should never be 

directed through the sliding contact 

surfaces (➔ fig 6 ); this could 

– damage the sliding contact surfaces 

and/or 

– expand fractured or split bearing 

outer rings, which would cause an 

increase in the mounting force 

required. 

Mounting using heat 

Larger bearings cannot usually be 

mounted in the cold state as the force 

required increases sharply with increasing 

bearing size. Therefore, the bearing 

or housing should be heated before 

mounting (➔ fig 7 ). 

The requisite temperature difference 

between the bearing ring and shaft or 

housing bore depends on the seating 

diameter. Generally, a temperature of 

60 to 80 °C above ambient is adequate 

to allow the rings to be easily mounted. 

The temperature to which a bearing 

can be heated also depends on the 

permissible temperature for the bearing 

which may be limited, for example, 

by the material of the seals. 

Note 

Maintenance-free spherical plain 

bearings and rod ends having sliding 

contact surfaces containing 

PTFE should never be subjected 

to temperatures in excess of 

+280 °C. PTFE is completely inert 

below this temperature but at higher 

temperatures (from approx. 

320 °C) it rapidly decomposes. 

The fluorine compounds released 

during this process are extremely 

toxic, even in small quantities. It 

should also be remembered that 

the material is dangerous to 

handle once it has been overheated 

even after it has cooled 

down again. 

2 

Never apply the mounting force via the sliding contact 

surfaces 

Mounting a heated bearing 

Fig 

6 

Fig 

7 


53




The use of SKF induction heaters 

has been found particularly beneficial 

(➔ fig 8 ). They are equipped with integral 

protection against overheating 

and automatically demagnetize. The 

induced current flow serves to rapidly 

heat the bearing. The non-metallic components, 

such as seals or PTFE fabric 

remain cold as does the heater itself. 

To ease the mounting of large bearings, 

particularly if they have been 

heated, it is possible to use slings and 

a hoist. Metal or textile slings placed 

around the outer ring can be used 

(➔ fig 9 ). A spring between the hoist 

hook and the sling also facilitates bearing 

handling. Heat-resistant gloves 

should be worn when handling hot 

components. 


Rod ends are fitted on the pins in the 

same way as spherical plain bearings. 

Slight heating will reduce the force 

required for mounting and reduce the 

danger of damaging associated components. 

When attaching rod ends to threaded 

rods or in extension tubes (➔ fig 

11 ) a counter lock nut should be used 

on the rod or on the external thread of 

the rod end. It should be securely 

tightened against the abutment surface 

on the rod end or the tube. 

Fig 

10 

Securing a rod end 

A bearing in position on an SKF 

induction heater 

Mounting a large heated bearing 

Fig 

8 

Fig 

9 

SKF has a comprehensive range 

of mechanical and hydraulic tools 

as well as heating equipment for 

bearing mounting and dismounting. 

Details of these tools can be 

found in the SKF catalogue 

MP3000 “SKF Maintenance and 

Lubrication Products” or in the 

online catalogue at 

www.mapro.skf.com. 

54 




Page ................ 4 Dismounting Page .............. 57 

Dismounting 

2 


If the bearings are to be re-used after 

dismounting, the same care and attention 

are required as when mounting. 

The requisite withdrawal force should 

always be applied to the ring which is 

to be dismounted. 

SKF offers a range of different puller 

types to accommodate many applications. 

If the shaft is pre-machined to 

accommodate the arms of a jaw puller, 

then a two- or three-armed puller can 

be used (➔ fig 1 ). In other cases 

where there is enough space behind 

the ring, a strong back puller such as 

the SKF TMBS series can be used 

(➔ fig 2 ). 

For large bearings with an interference 

fit, dismounting is considerably 

facilitated if the SKF oil injection 

method is used (➔ fig 3 ). In order to 

do this it is necessary to provide the 

necessary oil ducts and distributor 

grooves when designing the bearing 

arrangement (➔ page 46). 

Small bearings can be dismounted 

using a mounting dolly or a length of 

tubing applied to the outer ring. For 

larger bearings with an interference fit, 

a mechanical or hydraulic press can 

be used where possible. 

It is also possible to dismount bearings 

from housing bores by quickly 

heating the bearing housing without 

heating the bearing outer ring to any 

extent. 


To dismount rod ends the lock nut securing 

the shank should be loosened 

and, if possible, the rod end be unscrewed 

from its rod or tube. The rod 

end can then be removed from the pin 

in the same way as a bearing, e.g. 

using a puller. 

Removing a bearing with a jaw puller 

A strong back puller facilitates 

dismounting of the inner ring 

Dismounting a bearing using the SKF oil 

injection method 

Fig 

1 

Fig 

2 

Fig 

3 


55





Page ................ 4 Page .............. 16 General 

Bearing data – general 

3 Product data ............................................................ 57 


requiring maintenance................................................... 58 

General ........................................................................ 58 


with metric dimensions............................................ 62 

with inch dimensions............................................... 66 

with extended inner ring.......................................... 70 

Maintenance-free radial spherical plain bearings....... 72 

General ........................................................................ 72 

Bearings with sliding contact surface combination 

steel/sinter bronze composite ................................. 76 

steel/PTFE fabric ..................................................... 78 

steel/PTFE composite ............................................. 82 

Angular contact spherical plain bearings .................... 86 

General ........................................................................ 86 


surface combination steel/PTFE composite ............... 90 

Spherical plain thrust bearings ..................................... 92 

General ........................................................................ 92 


surface combination steel/PTFE composite................ 94 

Rod ends requiring maintenance.................................. 96 

General ....................................................................... 96 



with female thread for hydraulic cylinders ..............102 


with cylindrical section welding shank ....................106 

with rectangular section welding shank .................108 




Maintenance-free rod ends ...........................................114 

General ........................................................................114 


with female thread, steel/sinter bronze composite 118 

with male thread, steel/sinter bronze composite ....120 

with female thread, steel/PTFE fabric .....................122 

with male thread, steel/PTFE fabric ........................124 

with female thread, steel/PTFE composite..............126 

with male thread, steel/PTFE composite.................128 

Special solutions and related products........................130 

Plain bearings for road vehicles ..................................130 

Plain bearings for rail vehicles ....................................130 

Spherical plain bearings and rod ends for 

airframe applications ..................................................131 

Dry sliding bushings and flanged bushings.................132 

Dry sliding thrust washers and strip ...........................133 


requiring maintenance . . . . . . . . . . . . . . . . . . . . . 58 

Maintenance-free 

radial spherical plain bearings. . . . . . . . . . . . . . . 72 

Angular contact spherical plain bearings. . . . . . 86 

Spherical plain thrust bearings . . . . . . . . . . . . . . 92 

Rod ends requiring maintenance . . . . . . . . . . . . 96 

Maintenance-free rod ends . . . . . . . . . . . . . . . . . 114 

Special solutions and related products . . . . . . . 130 

3 

3.1 

3.2 

3.3 

3.4 

3.5 

3.6 

3.7 


57



Page ................ 4 Page .............. 16 Radial spherical plain bearings 




A characteristic feature of the SKF 

steel-on-steel spherical plain bearings 

is the outer ring, which is intentionally 

fractured at a given point so that it can 

be sprung apart to enable the inner ring 

to be inserted (➔ fig 1 ). The bearings 

are therefore non-separable and easy 

to handle. 

The surfaces are manganese phosphated 

and the sliding contact surface 

also treated with a running-in lubricant. 

This makes the bearings wear resistant 

and easy to run-in. To facilitate effective 

lubrication, all bearings – except 

some small sizes – have an annular 

groove and two lubrication holes in 

both outer and inner rings. Additionally, 

bearings with an outside diameter 

of 150 mm and above also have the 

“multi-groove system” (➔ page 6) in 

the outer ring sliding contact surface 

as standard (➔ fig 2 ). 

With the multi-groove system SKF 

has the answer to lubricant starvation 

in steel-on-steel bearings, which is 

otherwise prevalent where the bearings 

have to perform minor alignment 

movements under heavy constant 

direction loads. 

The multi-groove system (➔ fig 3 ) 

improves lubricant distribution in the 

heavy loaded zone and thus extends 

the service life and/or maintenance 

intervals. 

58 






Dimensions 

The dimensions of spherical plain bearings 

of series GE, GEH and GEG conform 

to ISO 12240-1:1998. 

Bearings with cylindrical extensions 

to the inner ring, series GEM, have 

a non-standard inner ring width but 

otherwise have the dimensions of 

series GE bearings. 

The dimensions of spherical plain 

bearings with inch dimensions, series 

GEZ, conform to the American Standard 

ANSI/ABMA Std. 22.2-1988. 

Tolerances 

The tolerances to which metric radial 

spherical plain bearings are made are 

given in Table 1 and those of inchsize 

bearings are given in Table 2 on 

page 60. Outer ring tolerances apply 

to conditions before fracture and surface 

treatment. Acccordingly, inner 

ring tolerances apply to rings before 

surface treatment. 

The tolerances are in accordance 

with ISO 12240-1:1998 (metric) and 

ANSI/ABMA Std. 22.2-1988 (inch-size 

bearings). 

The symbols used in the tolerance 

tables are explained in the following. 

d nominal bore diameter 

∆ dmp deviation of the mean bore 

diameter from the nominal 

D nominal outside diameter 

∆ Dmp deviation of the mean outside 


∆ Bs deviation of single inner ring 

width from the nominal 

∆ Cs deviation of single outer ring 


3.1 

Insertion of inner ring into outer ring 

Outer ring with multi-groove lubrication 

system in heavy duty ESL design 

Heavy-duty spherical plain bearing with 

multi-groove lubrication system and LS 

seals 

Fig 

1 

Fig 

2 

Fig 

3 


59





Tolerances of 

metric bearings 

Nominal Series GE, GEH, GEM Series GEG All series 

diameter Inner ring Inner ring Outer ring 

d, D ∆ dmp ∆ Bs ∆ dmp ∆ Bs ∆ Dmp ∆ Cs 

over incl. high low high low high low high low high low high low 

mm µm µm µm µm µm µm 

Table 

1 

6 0 –8 0 –120 – – – – – – – – 

6 10 0 –8 0 –120 – – – – 0 –8 0 –240 

10 18 0 –8 0 –120 +18 0 0 –180 0 –8 0 –240 

18 30 0 –10 0 –120 +21 0 0 –210 0 –9 0 –240 

30 50 0 –12 0 –120 +25 0 0 –250 0 –11 0 –240 

50 80 0 –15 0 –150 +30 0 0 –300 0 –13 0 –300 

80 120 0 –20 0 –200 +35 0 0 –350 0 –15 0 –400 

120 150 0 –25 0 –250 +40 0 0 –400 0 –18 0 –500 

150 180 0 –25 0 –250 +40 0 0 –400 0 –25 0 –500 

180 250 0 –30 0 –300 +46 0 0 –460 0 –30 0 –600 

250 315 0 –35 0 –350 – – – – 0 –35 0 –700 

315 400 – – – – – – – – 0 –40 0 –800 

400 500 – – – – – – – – 0 –45 0 –900 

Tolerances of 

inch-size bearings 

Nominal diameter Inner ring Outer ring 

Table 

2 

d, D ∆ dmp ∆ Bs ∆ Dmp ∆ Cs 

over incl. high low high low high low high low 

mm µm µm µm µm 

50,8 0 –13 0 –130 0 –13 0 –130 

50,8 76,2 0 –15 0 –130 0 –15 0 –130 

76,2 80,962 0 –20 0 –130 0 –15 0 –130 

80,962 120,65 0 –20 0 –130 0 –20 0 –130 

120,65 152,4 0 –25 0 –130 0 –25 0 –130 

152,4 177,8 – – – – 0 –25 0 –130 

177,8 222,25 – – – – 0 –30 0 –130 

60 






Radial internal clearance 


are produced with Normal radial internal 

clearance as standard; the actual values 

are shown in Table 3 . The availability 

of bearings with radial internal 

clearance smaller than Normal, C2, or 

greater than Normal, C3, should be 

checked before ordering. 

The clearance values for the metric 

bearings conform to ISO 12240-1:1998. 

Materials 

The inner and outer rings of SKF steelon-steel 

radial spherical plain bearings 

are made of through-hardened steel, 

ground and phosphated. The sliding 

contact surfaces are treated with a 

running-in lubricant. 

The double-lip rubbing seals of metric 

bearings with designation suffix 2RS 

are made of polyester elastomer. Polyurethane 

is used for the seals of the 

inch-size bearings. 

Bearings with designation suffix 2LS 

have a triple lip elastomer seal, with a 

steel backing, on each side of the 

bearing. 

Bore diameter Radial internal clearance 

d C2 Normal C3 

over incl. min max min max min max 

mm µm 

Metric bearings 1) 

12 8 32 32 68 68 104 

12 20 10 40 40 82 82 124 

20 35 12 50 50 100 100 150 

35 60 15 60 60 120 120 180 

60 90 18 72 72 142 142 212 

90 140 18 85 85 165 165 245 

140 200 18 100 100 192 192 284 

200 240 18 110 110 214 214 318 

240 300 18 125 125 239 239 353 

Inch-size bearings 

15,875 15 75 50 150 150 200 

15,875 50,800 25 105 80 180 180 260 

50,800 76,200 30 130 100 200 200 300 

76,200 152,400 40 160 130 230 230 350 

1) Bearings of series GEH with bore diameter d = 20, 35, 60 and 90 mm have a radial internal clearance 

corresponding to the values quoted for the next larger diameter range 

Table 

3 

3.1 

Permissible operating temperature 

range 

Steel-on steel spherical plain bearings 

can be used in the temperature range 

of –50 to +300 °C, but their load carrying 

capacity will be reduced at temperatures 

above +150 °C. 

For sealed bearings, the permissible 

operating temperature range is limited 

by the seal material, 

Radial internal clearance of steel-on-steel spherical plain bearings 

for 2RS seals 

• –30 to +130 °C for polyester elastomer 

(metric bearings), and 

• –20 to +80 °C for polyurethane (inchsize 

bearings), 

for 2LS seals 

• –25 to +120 °C for metric bearings. 

The operating temperature range for 

the actual grease used to lubricate the 

bearings must also be taken into consideration. 


61



Page ................ 4 Page .............. 16 Steel-on-steel spherical 


d 4 – 50 mm 

B 

b α M 

C 

r 2 

b 1 

D 

dk 

d 

GE .. E GE .. ES GEH .. ES-2RS GE .. ES-2LS 

Principal dimensions Angle Basic load ratings Mass Designation 

of tilt 1) dynamic static Standard Heavy duty 2) 

design 

design 

d D B C α C C 0 

mm degrees kN kg – 

4 12 5 3 16 2,04 10,2 0,003 GE 4 E – 

5 14 6 4 13 3,4 17 0,004 GE 5 E – 

6 14 6 4 13 3,4 17 0,004 GE 6 E – 

8 16 8 5 15 5,5 27,5 0,008 GE 8 E – 

10 19 9 6 12 8,15 40,5 0,012 GE 10 E – 

12 22 10 7 10 10,8 54 0,017 GE 12 E – 

15 26 12 9 8 17 85 0,032 GE 15 ES – 

26 12 9 8 17 85 0,032 GE 15 ES-2RS – 

17 30 14 10 10 21,2 106 0,050 GE 17 ES – 

30 14 10 10 21,2 106 0,050 GE 17 ES-2RS – 

20 35 16 12 9 30 146 0,065 GE 20 ES – 

35 16 12 9 30 146 0,065 GE 20 ES-2RS – 

42 25 16 17 48 240 0,16 GEH 20 ES-2RS – 

25 42 20 16 7 48 240 0,12 GE 25 ES – 

42 20 16 7 48 240 0,12 GE 25 ES-2RS – 

47 28 18 17 62 310 0,20 GEH 25 ES-2RS GEH 25 ES-2LS 

30 47 22 18 6 62 310 0,16 GE 30 ES – 

47 22 18 6 62 310 0,16 GE 30 ES-2RS GE 30 ES-2LS 


35 55 25 20 6 80 400 0,23 GE 35 ES – 

55 25 20 6 80 400 0,23 GE 35 ES-2RS GE 35 ES-2LS 


40 62 28 22 7 100 500 0,32 GE 40 ES – 

62 28 22 6 100 500 0,32 GE 40 ES-2RS GE 40 ES-2LS 


45 68 32 25 7 127 640 0,46 GE 45 ES – 

68 32 25 7 127 640 0,46 GE 45 ES-2RS GE 45 ES-2LS 


50 75 35 28 6 156 780 0,56 GE 50 ES – 

75 35 28 6 156 780 0,56 GE 50 ES-2RS GE 50 ES-2LS 

90 56 36 17 245 1 220 1,60 GEH 50 ES-2RS GEH 50 ES-2LS 

1) To fully utilize the angle of tilt, the shaft shoulder should not be made larger than d a max 

2) Bearings with outside diameter ≥ 150 mm have the multi-groove lubrication system in the outer ring as standard (➔ page 6) 

Bearings with outside diameter < 150 mm can also be supplied with multi-groove features; the designation then becomes GE .. ESL-2LS 

62 




Page ................ 4 Page .............. 16 

r b 

ra 

Da da D a 

Dimensions 


3.1 

d d k b b 1 M r 1 r 2 d a d a D a D a r a r b 

min min min max max min max max 

mm 

mm 

4 8 – – – 0,3 0,3 5,5 6,2 10,7 7,6 0,3 0,3 

5 10 – – – 0,3 0,3 6,6 8 12,6 9,5 0,3 0,3 

6 10 – – – 0,3 0,3 7,5 8 12,6 9,5 0,3 0,3 

8 13 – – – 0,3 0,3 9,6 10,2 14,5 12,3 0,3 0,3 

10 16 – – – 0,3 0,3 11,7 13,2 17,5 15,2 0,3 0,3 

12 18 – – – 0,3 0,3 13,8 15 20,4 17,1 0,3 0,3 

15 22 2,3 2,3 1,5 0,3 0,3 16,9 18,4 24,3 20,9 0,3 0,3 

22 2,3 2,3 1,5 0,3 0,3 16,9 18,4 24,3 22,8 0,3 0,3 

17 25 2,3 2,3 1,5 0,3 0,3 19 20,7 28,3 23,7 0,3 0,3 

25 2,3 2,3 1,5 0,3 0,3 19 20,7 28,3 26 0,3 0,3 

20 29 3,1 3,1 2 0,3 0,3 22,1 24,2 33,2 27,6 0,3 0,3 

29 3,1 3,1 2 0,3 0,3 22,1 24,2 33,2 30,9 0,3 0,3 

35,5 3,1 3,1 2 0,3 0,6 22,7 25,2 39,2 36,9 0,3 0,6 

25 35,5 3,1 3,1 2 0,6 0,6 28,2 29,3 39,2 33,7 0,6 0,6 

35,5 3,1 3,1 2 0,6 0,6 28,2 29,3 39,2 36,9 0,6 0,6 

40,7 3,1 3,1 2 0,6 0,6 28,6 29,5 44 41,3 0,6 0,6 

30 40,7 3,1 3,1 2 0,6 0,6 33,3 34,2 44 38,7 0,6 0,6 

40,7 3,1 3,1 2 0,6 0,6 33,3 34,2 44 41,3 0,6 0,6 

47 3,9 3,9 2,5 0,6 1 33,7 34,4 50,9 48,5 0,6 1 

35 47 3,9 3,9 2,5 0,6 1 38,5 39,8 50,9 44,6 0,6 1 

47 3,9 3,9 2,5 0,6 1 38,5 39,8 50,9 48,5 0,6 1 

53 3,9 3,9 2,5 0,6 1 38,8 39,8 57,8 54,5 0,6 1 

40 53 3,9 3,9 2,5 0,6 1 43,6 45 57,8 50,3 0,6 1 

53 3,9 3,9 2,5 0,6 1 43,6 45 57,8 54,5 0,6 1 

60 4,6 4,6 3 0,6 1 44,1 44,7 63,6 61 0,6 1 

45 60 4,6 4,6 3 0,6 1 49,4 50,8 63,6 57 0,6 1 

60 4,6 4,6 3 0,6 1 49,4 50,8 63,6 61 0,6 1 

66 4,6 4,6 3 0,6 1 49,8 50,1 70,5 66,2 0,6 1 

50 66 4,6 4,6 3 0,6 1 54,6 56 70,5 62,7 0,6 1 

66 4,6 4,6 3 0,6 1 54,6 56 70,5 66,2 0,6 1 

80 6,2 6,2 4 0,6 1 55,8 57,1 84,2 79,7 0,6 1 


63





d 60 – 300 mm 

B 

C 

r 2 

α 

D d k d 

r 1 

b 1 

GE .. ES GEH .. ES-2RS GE .. ES-2LS 


of tilt 1) dynamic static Standard Heavy duty 2) 

design 

design 



60 90 44 36 6 245 1 220 1,10 GE 60 ES – 

90 44 36 6 245 1 220 1,10 GE 60 ES-2RS GE 60 ES-2LS 


70 105 49 40 6 315 1 560 1,55 GE 70 ES – 

105 49 40 6 315 1 560 1,55 GE 70 ES-2RS GE 70 ES-2LS 


80 120 55 45 6 400 2 000 2,30 GE 80 ES – 

120 55 45 5 400 2 000 2,30 GE 80 ES-2RS GE 80 ES-2LS 


90 130 60 50 5 490 2 450 2,75 GE 90 ES – 

130 60 50 5 490 2 450 2,75 GE 90 ES-2RS GE 90 ES-2LS 


100 150 70 55 7 610 3 050 4,40 GE 100 ES – 

150 70 55 6 610 3 050 4,40 GE 100 ES-2RS GE 100 ES-2LS 


110 160 70 55 6 655 3 250 4,80 GE 110 ES – 

160 70 55 6 655 3 250 4,80 GE 110 ES-2RS GE 110 ES-2LS 


120 180 85 70 6 950 4 750 8,25 GE 120 ES – 

180 85 70 6 950 4 750 8,25 GE 120 ES-2RS GE 120 ES-2LS 

210 115 70 16 1 080 5 400 15,0 GEH 120 ES-2RS – 

140 210 90 70 7 1 080 5 400 11,0 GE 140 ES – 

210 90 70 7 1 080 5 400 11,0 GE 140 ES-2RS – 

160 230 105 80 8 1 370 6 800 14,0 GE 160 ES – 

230 105 80 8 1 370 6 800 14,0 GE 160 ES-2RS – 

180 260 105 80 6 1 530 7 650 18,5 GE 180 ES – 

260 105 80 6 1 530 7 650 18,5 GE 180 ES-2RS – 

200 290 130 100 7 2 120 10 600 28,0 GE 200 ES – 

290 130 100 7 2 120 10 600 28,0 GE 200 ES-2RS – 

220 320 135 100 8 2 320 11 600 35,5 GE 220 ES-2RS – 

240 340 140 100 8 2 550 12 700 40,0 GE 240 ES-2RS – 

260 370 150 110 7 3 050 15 300 51,5 GE 260 ES-2RS – 

280 400 155 120 6 3 550 18 000 65,0 GE 280 ES-2RS – 

300 430 165 120 7 3 800 19 000 78,5 GE 300 ES-2RS – 


2) Bearings with outside diameter ≥ 150 mm have the multi-groove lubrication system in the outer ring as standard (➔ page 6) 

Bearings with outside diameter < 150 mm can also be supplied with multi-groove features; the designation then becomes GE .. ESL-2LS 

64 




Page ................ 4 Page .............. 16 

r b 

ra 

Da da D a 

Dimensions 


3.1 



mm 

mm 

60 80 6,2 6,2 4 1 1 66,4 66,8 84,2 76 1 1 

80 6,2 6,2 4 1 1 66,4 66,8 84,2 79,7 1 1 

92 7,7 7,7 4 1 1 67 67 99 92 1 1 

70 92 7,7 7,7 4 1 1 76,7 77,9 99 87,4 1 1 

92 7,7 7,7 4 1 1 76,7 77,9 99 92 1 1 

105 7,7 7,7 4 1 1 77,5 78,3 113,8 104,4 1 1 

80 105 7,7 7,7 4 1 1 87,1 89,4 113,8 99,7 1 1 

105 7,7 7,7 4 1 1 87,1 89,4 113,8 104,4 1 1 

115 9,5 9,5 5 1 1 87,2 87,2 123,5 112,9 1 1 

90 115 9,5 9,5 5 1 1 97,4 98,1 123,5 109,3 1 1 

115 9,5 9,5 5 1 1 97,4 98,1 123,5 112,9 1 1 

130 11,3 11,3 5 1 1 98,2 98,4 143,2 131 1 1 

100 130 11,3 11,3 5 1 1 107,8 109,5 143,2 123,5 1 1 

130 11,3 11,3 5 1 1 107,8 109,5 143,2 131 1 1 

140 11,5 11,5 5 1 1 108,1 111,2 153,3 141,5 1 1 

110 140 11,5 11,5 5 1 1 118 121 153 133 1 1 

140 11,5 11,5 5 1 1 118 121 153 141,5 1 1 

160 13,5 13,5 6 1 1 119,5 124,5 172 157,5 1 1 

120 160 13,5 13,5 6 1 1 129,5 135,5 172 152 1 1 

160 13,5 13,5 6 1 1 129,5 135,5 172 157,5 1 1 

180 13,5 13,5 6 1 1 130 138,5 202,5 180 1 1 

140 180 13,5 13,5 6 1 1 149 155,5 202,5 171 1 1 

180 13,5 13,5 6 1 1 149 155,5 202,5 180 1 1 

160 200 13,5 13,5 6 1 1 169,5 170 222 190 1 1 

200 13,5 13,5 6 1 1 169,5 170 222 197 1 1 

180 225 13,5 13,5 6 1,1 1,1 191 199 250,5 214 1 1 

225 13,5 13,5 6 1,1 1,1 191 199 250,5 224,5 1 1 

200 250 15,5 15,5 7 1,1 1,1 212,5 213,5 279,5 237,5 1 1 

250 15,5 15,5 7 1,1 1,1 212,5 213,5 279,5 244,5 1 1 

220 275 15,5 15,5 7 1,1 1,1 232,5 239,5 309,5 271 1 1 

240 300 15,5 15,5 7 1,1 1,1 252,5 265 329,5 298 1 1 

260 325 15,5 15,5 7 1,1 1,1 273 288 359 321,5 1 1 

280 350 15,5 15,5 7 1,1 1,1 294 313,5 388,5 344,5 1 1 

300 375 15,5 15,5 7 1,1 1,1 314 336,5 418,5 371 1 1 


65




plain bearings, inch sizes 

d 0,5 – 2,5 in 

B 

C 

b 

M 

r 2 

α 

1 

D 

dk 

d 

GEZ .. ES 

GEZ .. ES-2RS 


of tilt 1) dynamic static 


mm/in degrees kN kg – 

12,700 22,225 11,100 9,525 6 14 41,5 0,020 GEZ 008 ES 

0,5000 0,8750 0,4370 0,3750 

15,875 26,988 13,894 11,913 6 21,6 65,5 0,035 GEZ 010 ES 

0,6250 1,0625 0,5470 0,4690 

19,050 31,750 16,662 14,275 6 31,5 93 0,055 GEZ 012 ES 

0,7500 1,2500 0,6560 0,5620 

22,225 36,513 19,431 16,662 6 42,5 127 0,085 GEZ 014 ES 

0,8750 1,4375 0,7650 0,6560 

25,400 41,275 22,225 19,050 6 56 166 0,12 GEZ 100 ES 

1,0000 1,6250 0,8750 0,7500 

41,275 22,225 19,050 6 56 166 0,12 GEZ 100 ES-2RS 

1,6250 0,8750 0,7500 

31,750 50,800 27,762 23,800 6 86,5 260 0,23 GEZ 104 ES 

1,2500 2,0000 1,0930 0,9370 

50,800 27,762 23,800 6 86,5 260 0,23 GEZ 104 ES-2RS 

2,0000 1,0930 0,9370 

34,925 55,563 30,150 26,187 5 104 310 0,35 GEZ 106 ES 

1,3750 2,1875 1,1870 1,0310 

55,563 30,150 26,187 5 104 310 0,35 GEZ 106 ES-2RS 

2,1875 1,1870 1,0310 

38,100 61,913 33,325 28,575 6 125 375 0,42 GEZ 108 ES 

1,5000 2,4375 1,3120 1,1250 

61,913 33,325 28,575 6 125 375 0,42 GEZ 108 ES-2RS 

2,4375 1,3120 1,1250 

44,450 71,438 38,887 33,325 6 170 510 0,64 GEZ 112 ES 

1,7500 2,8125 1,5310 1,3120 

71,438 38,887 33,325 6 170 510 0,64 GEZ 112 ES-2RS 

2,8125 1,5310 1,3120 

50,800 80,963 44,450 38,100 6 224 670 0,93 GEZ 200 ES 

2,0000 3,1875 1,7500 1,5000 

80,963 44,450 38,100 6 224 670 0,93 GEZ 200 ES-2RS 

3,1875 1,7500 1,5000 

57,150 90,488 50,013 42,850 6 280 850 1,30 GEZ 204 ES 

2,2500 3,5625 1,9690 1,6870 

90,488 50,013 42,850 6 280 850 1,30 GEZ 204 ES-2RS 

3,5625 1,9690 1,6870 

63,500 100,013 55,550 47,625 6 345 1 040 1,85 GEZ 208 ES 

2,5000 3,9375 2,1870 1,8750 

100,013 55,550 47,625 6 345 1 040 1,85 GEZ 208 ES-2RS 

3,9375 2,1870 1,8750 


66 




Page ................ 4 Page .............. 16 

r b 

ra 

Da da D a 

Dimensions 


3.1 



mm/in 

mm/in 

12,700 18,263 2,6 2,5 1,5 0,15 0,6 13,7 14,5 19,9 17,3 0,15 0,6 

0,5000 0,719 0,102 0,098 0,059 0,006 0,024 0,539 0,571 0,783 0,681 0,006 0,024 

15,875 22,835 3,2 3 2,5 0,15 1 17 18,1 23,6 21,7 0,15 1 

0,6250 0,899 0,126 0,118 0,098 0,006 0,039 0,669 0,713 0,929 0,854 0,006 0,039 

19,050 27,432 3,2 3 2,5 0,3 1 20,9 21,8 28,3 26,1 0,3 1 

0,7500 1,080 0,126 0,118 0,098 0,012 0,039 0,823 0,858 1,114 1,028 0,012 0,039 

22,225 31,953 3,2 3 2,5 0,3 1 24,2 25,4 33 30,4 0,3 1 

0,8750 1,258 0,126 0,118 0,098 0,012 0,039 0,953 1,000 1,299 1,197 0,012 0,039 

25,400 36,5 3,2 3 2,5 0,3 1 27,5 29 37,7 34,7 0,3 1 

1,0000 1,437 0,126 0,118 0,098 0,012 0,039 1,083 1,142 1,484 1,366 0,012 0,039 

36,5 3,2 3 2,5 0,3 1 27,5 29 37,7 35,2 0,3 1 

1,437 0,126 0,118 0,098 0,012 0,039 1,083 1,142 1,484 1,386 0,012 0,039 

31,750 45,593 4,8 5 4 0,6 1 34,8 36,2 47 43,3 0,6 1 

1,2500 1,795 0,189 0,197 0,158 0,024 0,039 1,370 1,425 1,850 1,705 0,024 0,039 

45,593 4,8 5 4 0,6 1 34,8 36,2 47 44,8 0,6 1 

1,795 0,189 0,197 0,158 0,024 0,039 1,370 1,425 1,850 1,764 0,024 0,039 

34,925 49,2 4,8 5 4 0,6 1 38,1 38,9 51,7 46,7 0,6 1 

1,3750 1,937 0,189 0,197 0,158 0,024 0,039 1,500 1,531 2,035 1,839 0,024 0,039 

49,2 4,8 5 4 0,6 1 38,1 38,9 51,7 47,1 0,6 1 

1,937 0,189 0,197 0,158 0,024 0,039 1,500 1,531 2,035 1,854 0,024 0,039 

38,100 54,737 4,8 5 4 0,6 1 41,4 43,4 58 52 0,6 1 

1,5000 2,155 0,189 0,197 0,158 0,024 0,039 1,630 1,709 2,283 2,047 0,024 0,039 

54,737 4,8 5 4 0,6 1 41,4 43,4 58 52,3 0,6 1 

2,155 0,189 0,197 0,158 0,024 0,039 1,630 1,709 2,283 2,059 0,024 0,039 

44,450 63,881 4,8 5 4 0,6 1 48,5 50,7 67,4 60,7 0,6 1 

1,7500 2,515 0,189 0,197 0,158 0,024 0,039 1,909 1,996 2,654 2,390 0,024 0,039 

63,881 4,8 5 4 0,6 1 48,5 50,7 67,4 61,3 0,6 1 

2,515 0,189 0,197 0,158 0,024 0,039 1,909 1,996 2,654 2,413 0,024 0,039 

50,800 73,025 4,8 5 4 0,6 1 55,1 57,9 75,9 69,4 0,6 1 

2,0000 2,875 0,189 0,197 0,158 0,024 0,039 2,169 2,280 2,988 2,732 0,024 0,039 

73,025 4,8 5 4 0,6 1 55,1 57,9 75,9 69,1 0,6 1 

2,875 0,189 0,197 0,158 0,024 0,039 2,169 2,280 2,988 2,720 0,024 0,039 

57,150 82,169 5,7 5 4 0,6 1 61,7 65,2 85,3 78,1 0,6 1 

2,2500 3,235 0,224 0,197 0,158 0,024 0,039 2,429 2,567 3,358 3,075 0,024 0,039 

82,169 5,7 5 4 0,6 1 61,7 65,2 85,3 79 0,6 1 

3,235 0,224 0,197 0,158 0,024 0,039 2,429 2,567 3,358 3,110 0,024 0,039 

63,500 91,186 9 8 6,5 0,6 1 68,3 72,3 94,7 86,6 0,6 1 

2,5000 3,590 0,354 0,315 0,256 0,024 0,039 2,689 2,846 3,728 3,409 0,024 0,039 

91,186 9 8 6,5 0,6 1 68,3 72,3 94,7 87 0,6 1 

3,590 0,354 0,315 0,256 0,024 0,039 2,689 2,846 3,728 3,425 0,024 0,039 


67




plain bearings, inch sizes 

d 2,75 – 6 in 

B 

C 

b 

M 

r 2 

α 

1 

D 

dk 

d 

GEZ .. ES 

GEZ .. ES-2RS 

Principal dimensions Angel Basic load ratings Mass Designation 



mm/in degrees kN kg – 

69,850 111,125 61,112 52,375 6 425 1 270 2,40 GEZ 212 ES 

2,7500 4,3750 2,4060 2,0620 

111,125 61,112 52,375 6 425 1 270 2,40 GEZ 212 ES-2RS 

4,3750 2,4060 2,0620 

76,200 120,650 66,675 57,150 6 500 1 500 3,10 GEZ 300 ES 

3,0000 4,7500 2,6250 2,2500 

120,650 66,675 57,150 6 500 1 500 3,10 GEZ 300 ES-2RS 

4,7500 2,6250 2,2500 

82,550 130,175 72,238 61,900 6 585 1 760 3,80 GEZ 304 ES 

3,2500 5,1250 2,8440 2,4370 

130,175 72,238 61,900 6 585 1 760 3,80 GEZ 304 ES-2RS 

5,1250 2,8440 2,4370 

88,900 139,700 77,775 66,675 6 680 2 040 4,80 GEZ 308 ES 

3,5000 5,5000 3,0620 2,6250 

139,700 77,775 66,675 6 680 2 040 4,80 GEZ 308 ES-2RS 

5,5000 3,0620 2,6250 

95,250 149,225 83,337 71,425 6 780 2 360 5,80 GEZ 312 ES 

3,7500 5,8750 3,2810 2,8120 

149,225 83,337 71,425 6 780 2 360 5,80 GEZ 312 ES-2RS 

5,8750 3,2810 2,8120 

101,600 158,750 88,900 76,200 6 900 2 650 7,00 GEZ 400 ES 

4,0000 6,2500 3,5000 3,0000 

158,750 88,900 76,200 6 900 2 650 7,00 GEZ 400 ES-2RS 

6,2500 3,5000 3,0000 

114,300 177,800 100 85,725 6 1 120 3 400 9,80 GEZ 408 ES 

4,5000 7,0000 3,9370 3,3750 

177,800 100 85,725 6 1 120 3 400 9,80 GEZ 408 ES-2RS 

7,0000 3,9370 3,3750 

120,650 187,325 105,562 90,475 6 1 250 3 750 11,5 GEZ 412 ES 

4,7500 7,3750 4,1560 3,5620 

187,325 105,562 90,475 6 1 250 3 750 11,5 GEZ 412 ES-2RS 

7,3750 4,1560 3,5620 

127 196,850 111,125 95,250 6 1 400 4 150 13,5 GEZ 500 ES 

5,0000 7,7500 4,3750 3,7500 

196,850 111,125 95,250 6 1 400 4 150 13,5 GEZ 500 ES-2RS 

7,7500 4,3750 3,7500 

152,400 222,250 120,650 104,775 5 1 730 5 200 17,5 GEZ 600 ES 

6,0000 8,7500 4,7500 4,1250 

222,250 120,650 104,775 5 1 730 5 200 17,5 GEZ 600 ES-2RS 

8,7500 4,7500 4,1250 


68 




Page ................ 4 Page .............. 16 

r b 

ra 

Da da D a 

Dimensions 


3.1 



mm/in 

mm/in 

69,850 100,330 9 8 6,5 0,6 1 74,9 79,6 105,7 95,3 0,6 1 

2,7500 3,950 0,354 0,315 0,256 0,024 0,039 2,949 3,134 4,161 3,752 0,024 0,039 

100,330 9 8 6,5 0,6 1 74,9 79,6 105,7 96 0,6 1 

3,950 0,354 0,315 0,256 0,024 0,039 2,949 3,134 4,161 3,780 0,024 0,039 

76,200 109,525 9 8 6,5 0,6 1 81,4 86,9 115 104 0,6 1 

3,0000 4,312 0,354 0,315 0,256 0,024 0,039 3,205 3,421 4,528 4,094 0,024 0,039 

109,525 9 8 6,5 0,6 1 81,4 86,9 115 104,8 0,6 1 

4,312 0,354 0,315 0,256 0,024 0,039 3,205 3,421 4,528 4,126 0,024 0,039 

82,550 118,745 9,3 8 6,5 0,6 1 88 94,2 124,4 112,8 0,6 1 

3,2500 4,675 0,366 0,315 0,256 0,024 0,039 3,465 3,709 4,898 4,441 0,024 0,039 

118,745 9,3 8 6,5 0,6 1 88 94,2 124,4 114,2 0,6 1 

4,675 0,366 0,315 0,256 0,024 0,039 3,465 3,709 4,898 4,496 0,024 0,039 

88,900 128,016 10,5 8 6,5 0,6 1 94,6 101,7 133,8 121,6 0,6 1 

3,5000 5,040 0,413 0,315 0,256 0,024 0,039 3,724 4,004 5,268 4,787 0,024 0,039 

128,016 10,5 8 6,5 0,6 1 94,6 101,7 133,8 122,8 0,6 1 

5,040 0,413 0,315 0,256 0,024 0,039 3,724 4,004 5,268 4,835 0,024 0,039 

95,250 136,906 10,5 8 6,5 0,6 1 101,2 108,6 143,1 130,1 0,6 1 

3,7500 5,390 0,413 0,315 0,256 0,024 0,039 3,984 4,276 5,634 5,122 0,024 0,039 

136,906 10,5 8 6,5 0,6 1 101,2 108,6 143,1 131,4 0,6 1 

5,390 0,413 0,315 0,256 0,024 0,039 3,984 4,276 5,634 5,173 0,024 0,039 

101,600 146,050 10,5 10 8 0,6 1 108 115,5 152,5 139 0,6 1 

4,0000 5,750 0,413 0,394 0,315 0,024 0,039 4,252 4,547 6,004 5,472 0,024 0,039 

146,050 10,5 10 8 0,6 1 108 115,5 152,5 139,5 0,6 1 

5,750 0,413 0,394 0,315 0,024 0,039 4,252 4,547 6,004 5,492 0,024 0,039 

114,300 164,465 11 10 8 1 1,1 122,5 130,5 171 156,5 1 1 

4,5000 6,475 0,433 0,394 0,315 0,039 0,043 4,823 5,138 6,732 6,161 0,039 0,039 

164,465 11 10 8 1 1,1 122,5 130,5 171 157 1 1 

6,475 0,433 0,394 0,315 0,039 0,043 4,823 5,138 6,732 6,181 0,039 0,039 

120,650 173,355 11 10 8 1 1,1 129 137,5 179 165 1 1 

4,7500 6,825 0,433 0,394 0,315 0,039 0,043 5,079 5,413 7,047 6,496 0,039 0,039 

173,355 11 10 8 1 1,1 129 137,5 179 166,5 1 1 

6,825 0,433 0,394 0,315 0,039 0,043 5,079 5,413 7,047 6,555 0,039 0,039 

127 182,626 11 10 8 1 1,1 135,5 144,5 188,5 173,5 1 1 

5,0000 7,190 0,433 0,394 0,315 0,039 0,043 5,335 5,689 7,421 6,831 0,039 0,039 

182,626 11 10 8 1 1,1 135,5 144,5 188,5 175,5 1 1 

7,190 0,433 0,394 0,315 0,039 0,043 5,335 5,689 7,421 6,909 0,039 0,039 

152,400 207,162 15 11 8 1 1,1 161 168 213,5 197 1 1 

6,0000 8,156 0,591 0,433 0,315 0,039 0,043 6,339 6,614 8,406 7,756 0,039 0,039 

207,162 15 11 8 1 1,1 161 168 213,5 197,5 1 1 

8,156 0,591 0,433 0,315 0,039 0,043 6,339 6,614 8,406 7,776 0,039 0,039 


69





with extended inner ring 

B 

b d 12 – 200 mm 

M 

C 

α 

r 2 

d d 

r 1 

b 1 

D dk 1 

GEG .. ES 

GEM .. ES-2RS 

Principal dimensions Angle Basic load ratings Mass Designation 1) 

of tilt dynamic static 



12 22 12 7 4 10,8 54 0,020 GEG 12 ESA 2) 

16 28 16 9 4 17,6 88 0,035 GEG 16 ES 

20 35 20 12 4 30 146 0,070 GEG 20 ES 

35 24 12 6 30 146 0,073 GEM 20 ES-2RS 

25 42 25 16 4 48 240 0,13 GEG 25 ES 

42 29 16 4 48 240 0,13 GEM 25 ES-2RS 

30 47 30 18 4 62 310 0,17 GEM 30 ES-2RS 

32 52 32 18 4 65,5 325 0,17 GEG 32 ES 

35 55 35 20 4 80 400 0,25 GEM 35 ES-2RS 

40 62 38 22 4 100 500 0,35 GEM 40 ES-2RS 

62 40 22 4 100 500 0,34 GEG 40 ES 

45 68 40 25 4 127 640 0,49 GEM 45 ES-2RS 

50 75 43 28 4 156 780 0,60 GEM 50 ES-2RS 

75 50 28 4 156 780 0,56 GEG 50 ES 

60 90 54 36 3 245 1 220 1,15 GEM 60 ES-2RS 

63 95 63 36 4 255 1 270 1,25 GEG 63 ES 

70 105 65 40 4 315 1 560 1,65 GEM 70 ES-2RS 

80 120 74 45 4 400 2 000 2,50 GEM 80 ES-2RS 

120 80 45 4 400 2 000 2,40 GEG 80 ES 

100 150 100 55 4 610 3 050 4,80 GEG 100 ES 

125 180 125 70 4 950 4 750 8,50 GEG 125 ES 

160 230 160 80 4 1 370 6 800 16,5 GEG 160 ES 

200 290 200 100 4 2 120 10 600 32,0 GEG 200 ES 

1) Bearings with outside diameters 150 mm have the multi-groove lubrication system in the outer ring sliding contact surface as standard (➔ page 6) 

2) Can only be relubricated via the outer ring 

70 




Page ................ 4 Page .............. 16 

r b 

ra 

Da 

da 

Dimensions 


3.1 

d d k d 1 b b 1 M r 1 r 2 d a d a D a D a r a r b 


mm 

mm 

12 18 15,5 2,3 – 1,5 0,3 0,3 14,5 15,5 20,4 17,1 0,3 0,3 

16 23 20 2,3 2,3 1,5 0,3 0,3 18,7 20 26,3 21,9 0,3 0,3 

20 29 25 3,1 3,1 2 0,3 0,3 23,1 25 33,2 27,6 0,3 0,3 

29 24 3,1 3,1 2 0,3 0,3 23 24 33,2 30,9 0,3 0,3 

25 35,5 30,5 3,1 3,1 2 0,6 0,6 29,2 30,5 39,2 33,7 0,6 0,6 

35,5 29 3,1 3,1 2 0,3 0,6 28,3 29 39,2 36,9 0,3 0,6 

30 40,7 34 3,1 3,1 2 0,3 0,6 33,5 34 44 41,3 0,3 0,6 

32 43 38 3,9 3,9 2,5 0,6 1 36,3 38 48,1 40,9 0,6 1 

35 47 40 3,9 3,9 2,5 0,6 1 38,8 40 50,9 48,5 0,6 1 

40 53 45 3,9 3,9 2,5 0,6 1 44 45 57,8 54,5 0,6 1 

53 46 3,9 3,9 2,5 0,6 1 44,8 46 57,8 50,3 0,6 1 

45 60 52 4,6 4,6 3 0,6 1 49,6 52 63,6 61 0,6 1 

50 66 57 4,6 4,6 3 0,6 1 54,8 57 70,5 66,2 0,6 1 

66 57 4,6 4,6 3 0,6 1 55,9 57 70,5 62,7 0,6 1 

60 80 68 6,2 6,2 4 0,6 1 65,4 68 84,2 79,7 0,6 1 

63 83 71,5 6,2 6,2 4 1 1 69,7 71,5 89,2 78,9 1 1 

70 92 78 7,7 7,7 4 0,6 1 75,7 78 99 92 0,6 1 

80 105 90 7,7 7,7 4 0,6 1 86,1 90 113,8 104,4 0,6 1 

105 91 7,7 7,7 4 1 1 88,7 91 113,8 99,7 1 1 

100 130 113 11,3 11,3 5 1 1 110,1 113 143,2 123,5 1 1 

125 160 138 13,5 13,5 6 1 1 136,5 138 172 152 1 1 

160 200 177 13,5 13,5 6 1 1 172 177 222 190 1 1 

200 250 221 15,5 15,5 7 1,1 1,1 213 221 279,5 237,5 1 1 


71



Page ................ 4 Page .............. 16 Maintenance-free radial spherical 


Maintenance-free radial spherical 


SKF maintenance-free spherical plain 

bearings are produced in a variety of 

designs and a wide range of sizes. 

Three sliding contact surface combinations 

are available: 

• steel/sinter bronze composite, 

suffix C 

• steel/PTFE fabric, suffix TX 

• steel/PTFE composite, suffix F 

The different designs of SKF maintenance-free 

spherical plain bearings are 

presented in Matrix 1 . The designs 

used depend on size and series, the 

main differences being in the material 

or in the design of the outer ring. 

Materials 

The materials for inner ring, outer ring, 

sliding layer and, where applicable, for 

the double-lip rubbing seals, are listed 

in Matrix 1 . The sliding contact surface 

of the inner rings of series GEC 

and GEP bearings are coated with a 

lithium base grease. 

72 






Matrix 

1 

Sliding contact 



1 

2 

3 

4 


1 

2 

3 

4 

Steel/PTFE composite 

Liner 

1 PTFE 

2 Tin bronze 

3 Copper layer 

4 Sheet steel backing 

1 PTFE fibres 

2 Reinforcement fibres 

3 Resin 

4 Backing 

Glass fibre reinforced plastic 

containing PTFE 

Inner ring 

C and CJ2 designs 

Through hardened and ground 

steel, sliding surface hard chromium 

plated and polished 

TXA and TXE designs 


steel, sliding surface hard chromium 

plated and polished 

TXG3E and TXG3A designs 

Stainless steel X 46 Cr 13/1.4034, 

hardened, ground, sliding surface 

polished 

Series GEP and GEC 

Carbon chromium steel 100 Cr 6/ 

1.3505, hardened, ground, sliding 

surface of series GEP hard chromium 

plated 

3.2 

Outer ring 

C design 

Sinter bronze composite moulded 

around the inner ring, with a butt 

joint 

CJ2 design 

Unhardened free cutting steel with 

sliding sleeve of sinter bronze 

composite pressed around the 

inner ring, without a butt joint. 

TXA and TXE designs 


steel 

TXA: split two-piece, held together 

by one or two steel bands 

TXE: fractured at one point 

TXG3A design 

Stainless steel X 46 Cr 13/1.4034, 

hardened, ground, split two-piece, 

held together by one steel band 

TXGR design 

d ≤ 17 mm: unhardened stainless 

steel X 22 CrNi 17/1.4057, pressed 

over the inner ring, no butt joint 

d ≥ 20 mm: hardened stainless 

steel X 46 Cr 13/1.4034, hardened, 

ground, fractured at one position 

Series GEP and GEC 

Series GEP: unhardened heat 

treatable steel C35/1.0501, 

ground, radially split. A liner of 

glass fibre reinforced plastic containing 

PTFE is glued in position in 

each outer ring half. 

Series GEC: Unhardened heat 

treatable steel C35/1.0501, 

ground. With sliding discs made of 

glass fibre reinforced plastic containing 

PTFE held by a cage made 

of unhardened steel C35/1.0501, 

which is pinned and screwed 

together with the outer ring. 

Seals 

To order 

Bearings with designation suffix 

2RS or 2LS (depending on bearing 

size) have double or triple lip seals 

on both sides 

None 

RS 

LS 

Operating 

temperature 

range 

Permissible: –50 to +180 °C 

For short periods: to +280 °C 

Bearings without seals: 


Sealed bearings: 

Permissible: –30 to +130 °C RS 

–25 to +120 °C LS 


For short periods: to +110 °C 

°C 

Reduced carrying 

capacity above 80 °C 

Reduced carrying capacity above 

60 °C for both sealed and unsealed 


Reduced carrying capacity above 

50 °C 

Lubrication 

To enhance sealing and protect 

against corrosion the free space in 

the housing may be filled with 

grease 

The bearings must not be 

lubricated 

Occasional relubrication is 

beneficial and extends service life 


73





Dimensions 

The dimensions of the maintenancefree 

spherical plain bearings conform 

to ISO 12240-1:1998. 

Tolerances 

The tolerances to which maintenancefree 

radial spherical plain bearings are 

made are given in Table 1 ; they are 

in accordance to ISO 12240/1:1998. 

The symbols used are explained in the 

following. 











Radial internal clearance, preload 

Maintenance free spherical plain bearings 

with a bore diameter up to and 

including 90 mm may have an internal 

clearance or a slight preload (negative 

clearance) because of their design. 

For these bearings, therefore, only the 

permissible maximum limit for bearing 

clearance is given in the table, and 

also only the permissible upper limit for 

the frictional moment depending on the 

preload in the circumferential direction 

under measuring load. 

The radial internal clearance and the 

upper limit of the permissible frictional 

moment of bearings with the sliding 

contact surface combination steel/sinter 

bronze composite and steel/PTFE 

fabric are given in Table 2 . The values 

for the clearance limits of bearings with 

the sliding contact surface combination 

steel/PTFE composite are listed in 

Table 3 . 

Nominal Inner ring Outer ring 

diameter 




18 0 –8 0 –120 0 –8 0 –240 

18 30 0 –10 0 –120 0 –9 0 –240 

30 50 0 –12 0 –120 0 –11 0 –240 

50 80 0 –15 0 –150 0 –13 0 –300 

80 120 0 –20 0 –200 0 –15 0 –400 

120 150 0 –25 0 –250 0 –18 0 –500 

150 180 0 –25 0 –250 0 –25 0 –500 

180 250 0 –30 0 –300 0 –30 0 –600 

250 315 0 –35 0 –350 0 –35 0 –700 

315 400 0 –40 0 –400 0 –40 0 –800 

400 500 0 –45 0 –450 0 –45 0 –900 

500 630 0 –50 0 –500 0 –50 0 –1 000 

630 800 0 –75 0 –750 0 –75 0 –1 100 

800 1 000 0 –100 0 –1 000 0 –100 0 –1 200 

1 000 1 250 0 –125 0 –1 250 0 –125 0 –1 300 

1 250 1 600 – – – – 0 –160 0 –1 600 

1 600 2 000 – – – – 0 –200 0 –2 000 

Tolerances of maintenance-free radial bearings 


range 

The permissible operating temperature 

range of maintenance-free spherical 

plain bearings depends on the sliding 

contact surface combination and also 

on the polyester elastomer material of 

the seals (➔ Matrix 1 ). However, if 

the load carrying capacity of the bearings 

is fully exploited the temperature 

range is narrowed. Under normal loads 

it is possible to operate at temperatures 

above the upper limit for brief periods. 

Table 

1 

74 






Internal clearance and frictional moment 

of steel/sinter bronze composite and 

Table 2 

steel/PTFE fabric bearings Bore diameter Series 

GE .. C, CJ2 

GE .. TXA, TXE, TXGR, TXG3A, TXG3E 

d Internal Frictional Internal 

clearance moment clearance 

over incl. max max min max 

mm µm Nm µm 

12 28 0,15 – 50 

12 17 35 0,25 – 50 

17 20 35 0,25 – 50 

20 30 44 0,40 – 50 

30 35 53 0,75 – 50 

35 40 53 0,75 – 50 

40 45 53 0,75 – 50 

45 50 53 0,75 – 50 

50 60 53 0,75 – 50 

60 70 – – – 50 

70 90 – – – 50 

90 140 – – 50 130 

140 180 – – 50 140 

180 300 – – 80 190 

3.2 

Internal clearance for steel/PTFE composite 


Bore diameter Radial internal clearance 

d Series GEP Series GEC 

over incl. min max min max 

Table 

3 

mm µm 

90 120 85 285 – – 

120 220 100 355 – – 

220 240 110 365 – – 

240 280 110 380 – – 

280 300 135 415 – – 

300 360 135 490 135 600 

360 380 135 490 135 630 

380 400 135 510 135 630 

400 480 145 540 145 640 

480 500 145 570 145 640 

500 600 160 610 160 670 

600 630 160 640 160 670 

630 670 170 670 170 690 

670 750 170 670 170 760 

750 800 170 700 170 760 

800 950 195 770 195 800 

950 1 000 195 820 195 800 

1 000 1 250 – – 220 820 


75



Page ................ 4 Page .............. 16 Maintenance-free spherical plain 

bearings with sliding contact surface 


B 

C 

α 

composite 

d 4 – 60 mm 

r 2 

r 1 

D 

dk 

d 

GE .. C GE .. CJ2 GEH .. C 





4 12 5 3 16 2,16 5,4 0,003 GE 4 C 

6 14 6 4 13 3,6 9 0,004 GE 6 C 

8 16 8 5 15 5,85 14,6 0,008 GE 8 C 

10 19 9 6 12 8,65 21,6 0,012 GE 10 C 

22 12 7 18 11,4 28,5 0,020 GEH 10 C 

12 22 10 7 10 11,4 28,5 0,017 GE 12 C 

26 15 9 18 18 45 0,030 GEH 12 C 

15 26 12 9 8 18 45 0,032 GE 15 C 

30 16 10 16 22,4 56 0,050 GEH 15 C 

17 30 14 10 10 22,4 56 0,050 GE 17 C 

35 20 12 19 31,5 78 0,090 GEH 17 C 

20 35 16 12 9 31,5 78 0,065 GE 20 C 

42 25 16 17 51 127 0,16 GEH 20 C 

25 42 20 16 7 51 127 0,12 GE 25 C 

47 28 18 17 65,5 166 0,20 GEH 25 C 

30 47 22 18 6 65,5 166 0,16 GE 30 C 

35 55 25 20 6 80 200 0,23 GE 35 CJ2 

40 62 28 22 7 100 250 0,32 GE 40 CJ2 

45 68 32 25 7 127 320 0,46 GE 45 CJ2 

50 75 35 28 6 156 390 0,56 GE 50 CJ2 

60 90 44 36 6 245 610 1,10 GE 60 CJ2 


76 




Page ................ 4 Page .............. 16 

r b 

ra 

Da 

da 

Dimensions 


d d k r 1 r 2 d a d a D a D a r a r b 


mm 

mm 

4 8 0,3 0,3 5,4 6,2 10,7 7,6 0,3 0,3 

3.2 

6 10 0,3 0,3 7,4 8 12,7 9,5 0,3 0,3 

8 13 0,3 0,3 9,4 10,2 14,6 12,3 0,3 0,3 

10 16 0,3 0,3 11,5 13,2 17,6 15,2 0,3 0,3 

18 0,3 0,3 11,6 13,4 20,6 17,1 0,3 0,3 

12 18 0,3 0,3 13,5 15 20,6 17,1 0,3 0,3 

22 0,3 0,3 13,7 16,1 24,5 20,9 0,3 0,3 

15 22 0,3 0,3 16,6 18,4 24,5 20,9 0,3 0,3 

25 0,3 0,3 16,7 19,2 28,5 23,7 0,3 0,3 

17 25 0,3 0,3 18,7 20,7 28,5 23,7 0,3 0,3 

29 0,3 0,3 18,9 21 33,4 27,6 0,3 0,3 

20 29 0,3 0,3 21,8 24,2 33,4 27,6 0,3 0,3 

35,5 0,3 0,6 22,1 25,2 39,5 33,7 0,3 0,6 

25 35,5 0,6 0,6 27,7 29,3 39,5 33,7 0,6 0,6 

40,7 0,6 0,6 27,9 29,5 44,4 38,7 0,6 0,6 

30 40,7 0,6 0,6 32,8 34,2 44,4 38,7 0,6 0,6 

35 47 0,6 1 37,9 39,8 51,4 44,7 0,6 1 

40 53 0,6 1 42,9 45 58,3 50,4 0,6 1 

45 60 0,6 1 48,7 50,8 64,2 57 0,6 1 

50 66 0,6 1 53,9 56 71,1 62,7 0,6 1 

60 80 1 1 65,4 66,8 85,8 76 1 1 


77






B α 

d 12 – 140 mm 

C 

r 2 

GE .. TX GE .. TX(G3)E-2LS GE .. TX(G3)A-2LS(-2RS) 

r 1 

D 

dk 

d 





12 22 10 7 10 30 50 0,017 GE 12 TXGR 

15 26 12 9 8 47,5 80 0,032 GE 15 TXGR 

17 30 14 10 10 60 100 0,050 GE 17 TXGR 

20 35 16 12 9 83 140 0,065 GE 20 TXG3E 

25 42 20 16 7 137 228 0,12 GE 25 TXE-2LS 

42 20 16 7 137 228 0,12 GE 25 TXG3E-2LS 

30 47 22 18 6 176 290 0,16 GE 30 TXE-2LS 

47 22 18 6 176 290 0,16 GE 30 TXG3E-2LS 

35 55 25 20 6 224 375 0,23 GE 35 TXE-2LS 

55 25 20 6 224 375 0,23 GE 35 TXG3E-2LS 

40 62 28 22 6 280 465 0,32 GE 40 TXE-2LS 

62 28 22 6 280 465 0,32 GE 40 TXG3E-2LS 

45 68 32 25 7 360 600 0,46 GE 45 TXE-2LS 

68 32 25 7 360 600 0,46 GE 45 TXG3E-2LS 

50 75 35 28 6 440 735 0,56 GE 50 TXE-2LS 

75 35 28 6 440 735 0,56 GE 50 TXG3E-2LS 

60 90 44 36 6 695 1 160 1,10 GE 60 TXE-2LS 

90 44 36 6 695 1 160 1,10 GE 60 TXG3E-2LS 

70 105 49 40 6 880 1 460 1,55 GE 70 TXE-2LS 

105 49 40 6 880 1 460 1,55 GE 70 TXG3A-2LS 

80 120 55 45 5 1 140 1 900 2,30 GE 80 TXE-2LS 

120 55 45 5 1 140 1 900 2,30 GE 80 TXG3A-2LS 

90 130 60 50 5 1 370 2 320 2,75 GE 90 TXE-2LS 

130 60 50 5 1 370 2 320 2,75 GE 90 TXG3A-2LS 

100 150 70 55 6 1 730 2 850 4,40 GE 100 TXA-2LS 

150 70 55 6 1 730 2 850 4,40 GE 100 TXG3A-2LS 

110 160 70 55 6 1 860 3 100 4,80 GE 110 TXA-2LS 

160 70 55 6 1 860 3 100 4,80 GE 110 TXG3A-2LS 

120 180 85 70 6 2 700 4 500 8,25 GE 120 TXA-2LS 

180 85 70 6 2 700 4 500 8,25 GE 120 TXG3A-2LS 

140 210 90 70 7 3 000 5 000 11,0 GE 140 TXA-2RS 

210 90 70 7 3 000 5 000 11,0 GE 140 TXG3A-2RS 


78 




Page ................ 4 Page .............. 16 

r b 

ra 

Da da D a 

Dimensions 




mm 

mm 

12 18 0,3 0,3 13,8 15 20,4 17,1 0,3 0,3 

3.2 

15 22 0,3 0,3 16,9 18,4 24,3 20,9 0,3 0,3 

17 25 0,3 0,3 19 20,7 28,3 23,7 0,3 0,3 

20 29 0,3 0,3 22,1 24,2 33,2 27,6 0,3 0,3 

25 35,5 0,6 0,6 28,2 29,3 39,2 36,9 0,6 0,6 

35,5 0,6 0,6 28,2 29,3 39,2 36,9 0,6 0,6 

30 40,7 0,6 0,6 33,3 34,2 44 41,3 0,6 0,6 

40,7 0,6 0,6 33,3 34,2 44 41,3 0,6 0,6 

35 47 0,6 1 38,5 39,8 51 48,5 0,6 1 

47 0,6 1 38,5 39,8 51 48,5 0,6 1 

40 53 0,6 1 43,5 45 57,5 54,5 0,6 1 

53 0,6 1 43,5 45 57,5 54,5 0,6 1 

45 60 0,6 1 49,5 50,8 63,5 61 0,6 1 

60 0,6 1 49,5 50,8 63,5 61 0,6 1 

50 66 0,6 1 54,5 56 70,5 66,5 0,6 1 

66 0,6 1 54,5 56 70,5 66,5 0,6 1 

60 80 1 1 66,5 66,8 84 80 1 1 

80 1 1 66,5 66,8 84 80 1 1 

70 92 1 1 76,5 77,9 99 92 1 1 

92 1 1 76,5 77,9 99 92 1 1 

80 105 1 1 87 89,4 113 105 1 1 

105 1 1 87 89,4 113 105 1 1 

90 115 1 1 97,5 98,1 123 113 1 1 

115 1 1 97,5 98,1 123 113 1 1 

100 130 1 1 108 109,5 144 131 1 1 

130 1 1 108 109,5 144 131 1 1 

110 140 1 1 118 121 153 141,5 1 1 

140 1 1 118 121 153 141,5 1 1 

120 160 1 1 130 135,5 172 157,5 1 1 

160 1 1 130 135,5 172 157,5 1 1 

140 180 1 1 149 155,5 202 180 1 1 

180 1 1 149 155,5 202 180 1 1 


79






B α 

d 160 – 300 mm 

C 

r 2 

r 1 

D 

dk 

d 





160 230 105 80 8 3 800 6 400 14,0 GE 160 TXA-2RS 

230 105 80 8 3 800 6 400 14,0 GE 160 TXG3A-2RS 

180 260 105 80 6 4 300 7 200 18,5 GE 180 TXA-2RS 

260 105 80 6 4 300 7 200 18,5 GE 180 TXG3A-2RS 

200 290 130 100 7 6 000 10 000 28,0 GE 200 TXA-2RS 

290 130 100 7 6 000 10 000 28,0 GE 200 TXG3A-2RS 

220 320 135 100 8 6 550 11 000 35,5 GE 220 TXA-2RS 

240 340 140 100 8 7 200 12 000 40,0 GE 240 TXA-2RS 

260 370 150 110 7 8 650 14 300 51,5 GE 260 TXA-2RS 

280 400 155 120 6 10 000 16 600 65,0 GE 280 TXA-2RS 

300 430 165 120 7 10 800 18 000 78,5 GE 300 TXA-2RS 


80 




Page ................ 4 Page .............. 16 

r b 

ra 

D a 

da 

Dimensions 




mm 

mm 

160 200 1 1 170 170 222 197 1 1 

200 1 1 170 170 222 197 1 1 

3.2 

180 225 1,1 1,1 191 199 250 224,5 1 1 

225 1,1 1,1 191 199 250 224,5 1 1 

200 250 1,1 1,1 213 213,5 279 244,5 1 1 

250 1,1 1,1 213 213,5 279 244,5 1 1 

220 275 1,1 1,1 233 239,5 309 271 1 1 

240 300 1,1 1,1 253 265 329 298 1 1 

260 325 1,1 1,1 273 288 359 321,5 1 1 

280 350 1,1 1,1 294 313,5 388 344,5 1 1 

300 375 1,1 1,1 314 336,5 418 371 1 1 


81





b 

combination steel/PTFE composite 

B 

d 100 – 480 mm 

M 

C 

D 

d 

r 1 

r 2 

α 

GEP .. FS 

GEC .. FSA 





100 150 71 67 2 600 900 4,51 GEP 100 FS 

110 160 78 74 2 720 1 080 5,35 GEP 110 FS 

120 180 85 80 2 850 1 270 7,96 GEP 120 FS 

140 210 100 95 2 1 200 1 800 13,0 GEP 140 FS 

160 230 115 109 2 1 600 2 400 16,6 GEP 160 FS 

180 260 128 122 2 2 080 3 100 24,4 GEP 180 FS 

200 290 140 134 2 2 450 3 650 33,5 GEP 200 FS 

220 320 155 148 2 3 050 4 550 45,8 GEP 220 FS 

240 340 170 162 2 3 550 5 400 53,7 GEP 240 FS 

260 370 185 175 2 4 250 6 400 69,5 GEP 260 FS 

280 400 200 190 2 5 000 7 500 89,5 GEP 280 FS 

300 430 212 200 2 5 600 8 300 110 GEP 300 FS 

320 440 160 135 4 2 800 4 150 73,0 GEC 320 FSA 

460 230 218 2 6 400 9 650 135 GEP 320 FS 

340 460 160 135 3 2 900 4 400 77,0 GEC 340 FSA 

480 243 230 2 7 100 10 800 150 GEP 340 FS 

360 480 160 135 3 3 100 4 650 80,0 GEC 360 FSA 

520 258 243 2 8 150 12 200 200 GEP 360 FS 

380 520 190 160 4 3 900 5 850 120 GEC 380 FSA 

540 272 258 2 9 150 13 700 220 GEP 380 FS 

400 540 190 160 3 4 050 6 100 125 GEC 400 FSA 

580 280 265 2 9 650 14 600 275 GEP 400 FS 

420 560 190 160 3 4 250 6 400 130 GEC 420 FSA 

600 300 280 2 10 600 16 000 300 GEP 420 FS 

440 600 218 185 3 5 200 7 800 180 GEC 440 FSA 

630 315 300 2 12 200 18 600 360 GEP 440 FS 

460 620 218 185 3 5 400 8 150 190 GEC 460 FSA 

650 325 308 2 12 900 19 600 380 GEP 460 FS 

480 650 230 195 3 6 000 9 000 220 GEC 480 FSA 

680 340 320 2 14 300 21 200 435 GEP 480 FS 


82 




Page ................ 4 Page .............. 16 

r b 

ra 

Da 

da 

Dimensions 




mm 

100 135 7,5 7,5 4 1 1 106,7 114,8 141,9 125,6 1 1 

mm 

3.2 

110 145 7,5 7,5 4 1 1 117 122 151 135 1 1 

120 160 7,5 7,5 4 1 1 127,5 135,5 171 149 1 1 

140 185 7,5 7,5 4 1 1 148 155,5 200 172,5 1 1 

160 210 7,5 7,5 4 1 1 169 175,5 218,5 195,5 1 1 

180 240 7,5 7,5 4 1,1 1,1 191 203 246,5 223,5 1 1 

200 260 11,5 11,5 5 1,1 1,1 211 219 276 242 1 1 

220 290 13,5 13,5 6 1,1 1,1 232 245 304,5 270 1 1 

240 310 13,5 13,5 6 1,1 1,1 252,5 259 323,5 288,5 1 1 

260 340 15,5 15,5 7 1,1 1,1 273,5 285 352,5 316,5 1 1 

280 370 15,5 15,5 7 1,1 1,1 294 311 381,5 344,5 1 1 

300 390 15,5 15,5 7 1,1 1,1 314,5 327 411 363 1 1 

320 380 21 – 8 1,1 3 327 344 427 381 1 3 

414 21 21 8 1,1 3 335 344 434 385 1 3 

340 400 21 – 8 1,1 3 347 366 447 401 1 3 

434 21 21 8 1,1 3 356 359 453 404 1 3 

360 420 21 – 8 1,1 3 367 388 467 421 1 3 

474 21 21 8 1,1 4 377 397 490 441 1 4 

380 450 21 – 8 1,5 4 389 407 505 451 1,5 4 

494 21 21 8 1,5 4 398 412 508 460 1,5 4 

400 470 21 – 8 1,5 4 409 429 525 471 1,5 4 

514 21 21 8 1,5 4 418 431 549 478 1,5 4 

420 490 21 – 8 1,5 4 429 451 545 491 1,5 4 

534 21 21 8 1,5 4 439 441 568 497 1,5 4 

440 520 27 – 10 1,5 4 449 472 584 521 1,5 4 

574 27 27 10 1,5 4 460 479 596 534 1,5 4 

460 540 27 – 10 1,5 4 469 494 604 541 1,5 4 

593 27 27 10 1,5 5 481 496 612 552 1,5 5 

480 565 27 – 10 2 5 491 516 631 566 2 5 

623 27 27 10 2 5 503 522 641 580 2 5 


83





combination steel/PTFE composite 

B 

b 

d 500 – 1 250 mm 

C 

M 

D 

d 

r 1 

r 2 

α 

GEP .. FS 

GEC .. FSA 





500 670 230 195 3 6 200 9 300 230 GEC 500 FSA 

710 355 335 2 15 300 23 200 500 GEP 500 FS 

530 710 243 205 3 6 950 10 400 270 GEC 530 FSA 

750 375 355 2 17 000 25 500 585 GEP 530 FS 

560 750 258 215 4 7 650 11 400 320 GEC 560 FSA 

800 400 380 2 19 600 29 000 730 GEP 560 FS 

600 800 272 230 3 8 800 13 200 385 GEC 600 FSA 

850 425 400 2 22 000 33 500 860 GEP 600 FS 

630 850 300 260 3 10 400 15 600 495 GEC 630 FSA 

900 450 425 2 24 500 37 500 1 040 GEP 630 FS 

670 900 308 260 3 11 000 16 600 560 GEC 670 FSA 

950 475 450 2 27 500 41 500 1 210 GEP 670 FS 

710 950 325 275 3 12 500 18 600 655 GEC 710 FSA 

1 500 475 2 31 000 46 500 1 400 GEP 710 FS 

750 1 335 280 3 13 400 20 000 735 GEC 750 FSA 

1 060 530 500 2 34 500 52 000 1 670 GEP 750 FS 

800 1 060 355 300 3 15 300 22 800 865 GEC 800 FSA 

1 120 565 530 2 39 000 58 500 1 940 GEP 800 FS 

850 1 120 365 310 3 16 600 25 000 980 GEC 850 FSA 

1 220 600 565 2 45 000 67 000 2 600 GEP 850 FS 

900 1 180 375 320 3 18 300 27 500 1 100 GEC 900 FSA 

1 250 635 600 2 49 000 73 500 2 690 GEP 900 FS 

950 1 250 400 340 3 20 400 30 500 1 350 GEC 950 FSA 

1 360 670 635 2 56 000 85 000 3 620 GEP 950 FS 

1 1 320 438 370 3 23 200 35 500 1 650 GEC 1000 FSA 

1 450 710 670 2 63 000 95 000 4 470 GEP 1000 FS 

1 060 1 400 462 390 3 26 500 40 000 1 950 GEC 1060 FSA 

1 120 1 460 462 390 3 28 000 41 500 2 050 GEC 1120 FSA 

1 180 1 540 488 410 3 31 000 46 500 2 400 GEC 1180 FSA 

1 250 1 630 515 435 3 34 500 52 000 2 850 GEC 1250 FSA 


84 




Page ................ 4 Page .............. 16 

r b 

ra 

Da 

da 

Dimensions 




mm 

500 585 27 – 10 2 5 511 537 651 586 2 5 

643 27 27 10 2 5 523 536 670 598 2 5 

mm 

3.2 

530 620 27 – 10 2 5 541 570 691 621 2 5 

673 27 27 10 2 5 554 558 709 626 2 5 

560 655 27 – 10 2 5 571 602 731 656 2 5 

723 27 27 10 2 5 585 602 758 673 2 5 

600 700 27 – 10 2 5 611 645 781 701 2 5 

773 27 27 10 2 6 627 645 801 719 2 6 

630 740 35 – 13 3 6 645 676 827 741 3 6 

813 35 35 13 3 6 661 677 850 757 3 6 

670 785 35 – 13 3 6 685 722 877 786 3 6 

862 35 35 13 3 6 702 719 898 802 3 6 

710 830 35 – 13 3 6 725 763 926 831 3 6 

912 35 35 13 3 6 743 762 946 849 3 6 

750 875 35 – 13 3 6 766 808 976 876 3 6 

972 35 35 13 3 6 784 814 1 005 904 3 6 

800 930 35 – 13 3 6 816 859 1 036 931 3 6 

1 022 35 35 13 3 6 836 851 1 062 951 3 6 

850 985 35 – 13 3 6 866 914 1 096 986 3 6 

1 112 35 35 13 3 7,5 888 936 1 156 1 035 3 7,5 

900 1 040 35 – 13 3 6 916 970 1 156 1 041 3 6 

1 142 35 35 13 3 7,5 938 949 1 183 1 063 3 7,5 

950 1 100 40 – 15 4 7,5 968 1 024 1 221 1 101 4 7,5 

1 242 40 40 15 4 7,5 993 1 045 1 290 1 156 4 7,5 

1 000 1 160 40 – 15 4 7,5 1 019 1 074 1 290 1 161 4 7,5 

1 312 40 40 15 4 7,5 1 045 1 103 1 378 1 221 4 7,5 

1 060 1 240 40 – 15 4 7,5 1 079 1 150 1 370 1 241 4 7,5 

1 120 1 310 40 – 15 4 7,5 1 139 1 225 1 430 1 311 4 7,5 

1 180 1 380 40 – 15 4 7,5 1 199 1 290 1 510 1 381 4 7,5 

1 250 1 460 40 – 15 4 7,5 1 270 1 366 1 600 1 461 4 7,5 


85



Page ................ 4 Page .............. 16 Angular contact spherical plain 


Angular contact spherical plain 


The sphered sliding contact surfaces 

of angular contact spherical plain bearings 

are inclined at an angle to the 

bearing axis (➔ fig 1 ). Consequently, 

the bearings are particularly suitable 

for the accommodation of combined 

(radial and axial) loads. Singly mounted 

angular contact bearings can only 

support axial loads acting in one direction. 

The bearings are of separable 

design, e.g. the rings can be mounted 

separately. 

86 






Dimensions 

The boundary dimensions of SKF angular 

contact spherical plain bearings 

conform to ISO 12240-2:1998. 

Tolerances 

SKF angular contact spherical plain 

bearings are made to the tolerances 

specified in Table 1 . The tolerances 

conform to ISO 12240-2:1998. 


table are explained in the following. 











∆ Ts deviation of single bearing width 

(abutment width) from the 

nominal 

Nominal Inner ring Outer ring Total width 

diameter 


1) 

∆ Ts 

over incl. high low high low high low high low high low 

mm µm µm µm µm µm 

18 50 0 –12 0 –240 0 –14 0 –240 +250 –400 

50 80 0 –15 0 –300 0 –16 0 –300 +250 –500 

80 120 0 –20 0 –400 0 –18 0 –400 +250 –600 

120 150 – – – – 0 –20 0 –500 – – 

150 180 – – – – 0 –25 0 –500 – – 

1) The width tolerance is related to d 

Tolerances for angular contact spherical plain bearings 

Table 

1 

3.3 

Load line through an angular contact 

spherical plain bearing 

Fig 

1 


87





Radial internal clearance, preload 

Internal clearance in a single angular 

contact spherical plain bearing is only 

obtained after mounting and is dependent 

on adjustment against a second 

bearing, which provides axial location 

in the opposite direction. 

Angular contact spherical plain bearings 

are generally mounted in pairs in 

a back-to-back or face-to-face arrangement; 

the bearings are adjusted against 

each other by axially displacing one 

bearing ring until a specific bearing 

load of 10 N/mm 2 is obtained. The preload 

prevents some of the elastic and 

plastic deformations, which would 

occur under load and after a short 

period of operation. When adjusting 

bearings for the first time in a new 

arrangement, the specific bearing load 

of 10 N/mm 2 is achieved when the frictional 

moment and the axial preload 

force lie in the ranges specified in 

Table 2 . 

Bearing Frictional Axial 

moment preload 

for 

force 

10 N/mm 2 for 

min max 10 N/mm 2 

– Nm N 

GAC 25 F 7 9 5 600 

GAC 30 F 12 14 7 500 

GAC 35 F 16 19 9 300 

GAC 40 F 21 25 10 600 

GAC 45 F 26 32 13 600 

GAC 50 F 31 38 12 900 

GAC 60 F 51 62 17 800 

GAC 70 F 76 92 21 000 

GAC 80 F 105 126 30 000 

GAC 90 F 153 184 41 700 

GAC 100 F 180 216 39 500 

GAC 110 F 273 328 54 500 

GAC 120 F 317 380 69 500 

Table 2 

Fig 2 

Standard angular contact spherical plain 

bearing 

Materials 

The inner and outer rings of SKF 

angular contact spherical plain bearings 

are made of through hardened and 

ground steel. The sliding surface of 

the inner ring is hard chromium plated 

and coated with a lithium base grease. 

The sliding layer of glass fibre reinforced 

plastic containing PTFE additives 

is injection moulded in the outer ring. 

Frictional moment and axial preload 

force 


range 

Spherical plain bearings with the sliding 


steel/PTFE composite can be used in 

the temperature range of –40 to +75 °C, 

although brief periods of operation up 

to +110 °C are permitted. However, 


will be reduced at temperatures 


88 






Fig 

3 

Fig 

4 

Fig 

5 

Maintenance-free bearing, sliding 

contact surface combination steel/PTFE 

fabric 

Steel-on-steel bearing 

Steel-on-steel bearing with “waffle” 

grooves 

Special designs 

Special operating conditions may call 

for angular contact spherical plain 


combinations steel-on-steel or 

steel/PTFE fabric and, consequently, 

such bearings are also produced by 

SKF. 

Bearings with sliding contact surface 

combination steel/PTFE fabric (➔ fig 

3 ) should be used when maintenance-free 

operation is specified and 

where the bearing arrangement is such 

that the presence of any lubricant is 

not permitted. 

Steel-on-steel bearings (➔ fig 4 ) 

are preferred where operating temperatures, 

loads or load frequencies are 

high or where shock loads occur. To 

ensure correct operation, steel-onsteel 

bearings must be provided with 

an adequate supply of lubricant. Depending 

on the lubricant the sliding 

surface of the outer ring may be 

equipped with various types of lubrication 

grooves (➔ figs 5 and 6 ). 

Inch-size steel-on-steel angular contact 

spherical plain bearings are also 

available to order. 

Fig 

Steel-on-steel bearing with “diamond 

thread” grooves 

6 

3.3 


89



Page ................ 4 Page .............. 16 Maintenance-free angular contact 

s 

spherical plain bearings with sliding 

T 


C 


r 1 

d 25 – 120 mm 

r 2 

r 2 r 1 

B 

dk 

D 

d 

α 



d D T α C C 0 


25 47 15 3,5 21,6 34,5 0,14 GAC 25 F 

30 55 17 3,5 27 43 0,21 GAC 30 F 

35 62 18 3,5 32,5 52 0,27 GAC 35 F 

40 68 19 3,5 39 62 0,33 GAC 40 F 

45 75 20 3 45,5 73,5 0,42 GAC 45 F 

50 80 20 3 53 85 0,46 GAC 50 F 

60 95 23 3 69,5 112 0,73 GAC 60 F 

70 110 25 2,5 88 143 1,05 GAC 70 F 

80 125 29 2,5 110 176 1,55 GAC 80 F 

90 140 32 2,5 134 216 2,10 GAC 90 F 

100 150 32 2 170 270 2,35 GAC 100 F 

110 170 38 2 200 320 3,70 GAC 110 F 

120 180 38 1,5 240 380 4,00 GAC 120 F 

90 




Page ................ 4 Page .............. 16 

r a 

ra 

Da 

d a 

db 

D b 

Dimensions 


d d k B C r 1 r 2 s d a d b D a D b r a 

min min max max min min max 

mm 

mm 

25 42 15 14 0,6 0,3 0,6 29 39 34 43 0,6 

30 49,5 17 15 1 0,3 1,3 35 45 39 50,5 1 

35 55,5 18 16 1 0,3 2,1 40 50 45 56,5 1 

40 62 19 17 1 0,3 2,8 45 54 50 63 1 

3.3 

45 68,5 20 18 1 0,3 3,5 51 60 55 69 1 

50 74 20 19 1 0,3 4,3 56 67 60 74,5 1 

60 88,5 23 21 1,5 0,6 5,7 68 77 70 90 1,5 

70 102 25 23 1,5 0,6 7,2 78 92 85 103 1,5 

80 115 29 25,5 1,5 0,6 8,6 88 104 95 116 1,5 

90 128,5 32 28 2 0,6 10,1 101 118 105 129 2 

100 141 32 31 2 0,6 11,6 112 128 120 141 2 

110 155 38 34 2,5 0,6 13 124 145 130 156 2,5 

120 168 38 37 2,5 0,6 14,5 134 155 140 169 2,5 


91



Page ................ 4 Page .............. 16 Spherical plain thrust bearings 

Spherical plain thrust 


Spherical plain thrust bearings have a 

sphered surface on the shaft washer 

and a hollow, correspondingly sphered 

surface in the housing washer (➔ fig 

1 ). They are primarily intended to 

carry axial loads but are also suitable 

for the accommodation of radial loads 

in addition to simultaneously acting 

axial loads. The radial load component 

of combined loads should not exceed 

50 % of the simultaneously acting axial 

load. When radial loads are very heavy 

it may be advisable to combine thrust 

bearings with larger radial bearings of 

dimension series GE (➔ fig 2 ). 

Spherical plain thrust bearings are 

of separable design, e.g. the washers 

can be mounted separately. 

Fig 

1 

Standard spherical plain thrust bearing 

Combination of radial and thrust 


Fig 

2 

92 




Page ................ 4 Page .............. 16 Spherical plain thrust bearings 

Dimensions 

The principal dimensions of SKF spherical 

plain thrust bearings conform to 

ISO 12240-3:1998. 

Fig 

3 

Fig 

4 

Tolerances 

SKF spherical plain thrust bearings are 

made to the tolerances specified in 

Table 1 . The tolerances conform to 

ISO 12240-3:1998. 


table are explained in the following. 

Steel-on-steel spherical plain thrust 

bearing with lubrication hole and groove 

Maintenance-free thrust bearing with 

sliding contact surface combination 








∆ Bs deviation of single shaft washer 


∆ Cs deviation of single housing 

washer width from the nominal 

∆ Ts deviation of single height of 

thrust bearing from the nominal 

Materials 

The shaft and housing washers of 

SKF spherical plain thrust bearings are 

made of through hardened and ground 

steel. The sliding surface of the shaft 

washer is hard chromium plated and 

coated with a lithium base grease. The 

sliding layer of glass fibre reinforced 

plastic containing PTFE additives is 

injection moulded in the housing 

washer. 


range 

Spherical plain bearings with the sliding 


steel/PTFE composite can be used in 

the temperature range –40 to +75 °C, 

although brief periods of operation up 

to +110 °C are permitted. However, 


will be reduced at temperatures 


Special designs 

Special operating conditions may call 

for spherical plain thrust bearings with 

the sliding contact surface combinations 

steel-on-steel or steel/PTFE 

fabric and consequently they are produced 

to order by SKF. 

Steel-on-steel bearings (➔ fig 3 ) 

are preferred where operating temperatures, 

loads or load frequencies are 

high or where shock loads occur. 

Bearings with the sliding contact 

surface steel/PTFE fabric (➔ fig 4 ) 

should be used when maintenancefree 

operation is specified and where 

the bearing arrangement is such that 

the presence of any lubricant is not 

permitted. 

Tolerances of spherical plain thrust bearings 

Nominal Shaft washer Housing washer Single height 

diameter 

d, D ∆ dmp ∆ Bs ∆ Dmp ∆ Cs ∆ Ts 

1) 

over incl. high low high low high low high low high low 

mm µm µm µm µm µm 

– 18 0 –8 0 –240 – – – – +250 –400 

18 30 0 –10 0 –240 – – – – +250 –400 

30 50 0 –12 0 –240 0 –11 0 –240 +250 –400 

50 80 0 –15 0 –300 0 –13 0 –300 +250 –500 

80 120 0 –20 0 –400 0 –15 0 –400 +250 –600 

120 150 – – – – 0 –18 0 –500 – – 

150 180 – – – – 0 –25 0 –500 – – 

180 230 – – – – 0 –30 0 –600 – – 

Table 

1 

3.4 

1) The width tolerance is related to d 


93



Page ................ 4 Page .............. 16 

d1 

Maintenance-free spherical plain 

thrust bearings with sliding contact 

surface combination steel/PTFE 

composite 

d 17 – 120 mm 

s 

dk 

r 1 

T 

C 

B 

α 

r 1 

d 

D1 

D 



d D T α C C 0 


17 47 16 5 36,5 58,5 0,14 GX 17 F 

20 55 20 5 46,5 73,5 0,25 GX 20 F 

25 62 22,5 5 69,5 112 0,42 GX 25 F 

30 75 26 5 95 153 0,61 GX 30 F 

35 90 28 6 134 216 0,98 GX 35 F 

40 105 32 6 173 275 1,50 GX 40 F 

45 120 36,5 6 224 355 2,25 GX 45 F 

50 130 42,5 6 275 440 3,15 GX 50 F 

60 150 45 6 375 600 4,65 GX 60 F 

70 160 50 5 475 750 5,40 GX 70 F 

80 180 50 5 570 915 6,95 GX 80 F 

100 210 59 5 735 1 180 11,0 GX 100 F 

120 230 64 4 880 1 430 14,0 GX 120 F 

94 




Page ................ 4 Page .............. 16 

r a 

r a 

d a 

Da 

Dimensions 


d d k d 1 D 1 B C r 1 s d a D a r a 

min min max max 

mm 

mm 

17 52 43,5 27 11,8 11,2 0,6 11 34 37 0,6 

20 60 50 31 14,5 13,8 1 12,5 40 44 1 

25 68 58,5 34,5 16,5 16,7 1 14 45 47 1 

30 82 70 42 19 19 1 17,5 56 59 1 

35 98 84 50,5 22 20,7 1 22 66 71 1 

40 114 97 59 27 21,5 1 24,5 78 84 1 

45 128 110 67 31 25,5 1 27,5 89 97 1 

50 139 120 70 33 30,5 1 30 98 105 1 

3.4 

60 160 140 84 37 34 1 35 109 120 1 

70 176 153 94,5 42 36,5 1 35 121 125 1 

80 197 172 107,5 43,5 38 1 42,5 135 145 1 

100 222 198 127 51 46 1 45 155 170 1 

120 250 220 145 53,5 50 1 52,5 170 190 1 


95



Page ................ 4 Page .............. 16 Rod ends requiring maintenance 

Rod ends requiring 

maintenance 


Steel-on-steel rod ends consist of a 

rod end housing and a normal steelon-steel 

spherical plain bearing which 

is held in position axially in the housing. 

The rod ends are available with 

female thread (➔ fig 1 ), male thread 

(➔ fig 2 ) or with a welding shank 

(➔ fig 3 ). 

Fig 

1 

Rod end with 

female thread 

Fig 

2 

Rod end with male 

thread 

Fig 

3 

96 

Rod end with 

welding shank 





Steel-on-steel bronze rod ends 

Steel-on-bronze rod ends consist of a 

rod end housing and a steel-on-bronze 

spherical plain bearing having an outer 

ring made of bronze. The bearing is 

held in position by staking at both sides 

of the outer ring. These rod ends are 

available with female or male thread. 

Dimensions 

The dimensions of SKF rod ends are 

standardized and correspond to the 

standards listed in Table 1 . Rod ends 

identified by designation suffix VZ019 

have a male thread which deviates 

from the ISO standard but conforms to 

the CETOP 1) Recommendation RP 

103 P. 

The female and male threads of SKF 

rod ends correspond to ISO 965-1:1998. 

Tolerances 

The tolerances to which SKF rod ends 

are made conform to ISO 12240- 

4:1998. The tolerances for the steelon-steel 

rod end inner rings are given 

in Table 2 and those for steel-onbronze 

rod end inner rings are given 

in Table 3 . 

The symbols used in these tables 

are defined in the following. 






Series 

Standards 

Standards 

SA(A) ISO 12240-4:1998 

SI(A) ISO 12240-4:1998 

SC ISO 12240-4:1998 

SCF – 

SIJ ISO 8138:1991 

SIR – 

SIQG 

CETOP RP 88 H 

SAKAC ISO 12240-4:1998 

SIKAC ISO 12240-4:1998 

SIKAC/VZ019 ISO 8139:1991, CETOP RP 103 P 

Tolerances for steel-on-steel rod end inner rings 

Bore Series Series 

diameter SA(A), SI(A), SIJ, SIR, SC, SCF SIQG 

d ∆ dmp ∆ Bs ∆ dmp ∆ Bs 

over incl. low high low high low high low high 


Table 

Table 

10 0 –8 0 –120 – – – – 

10 18 0 –8 0 –120 +18 0 0 –180 

18 30 0 –10 0 –120 +21 0 0 –210 

30 50 0 –12 0 –120 +25 0 0 –250 

50 80 0 –15 0 –150 +30 0 0 –300 

80 120 0 –20 0 –200 +35 0 0 –350 

120 180 – – – – +40 0 0 –400 

180 250 – – – – +46 0 0 –460 

1 

2 

3.5 

Tolerances for steel-on-bronze rod end inner rings 

Bore 

diameter 

Series 

SIKAC, SAKAC 

Table 

3 

d ∆ dmp ∆ Bs 

over incl. high low high low 

mm µm µm 

6 +12 0 0 –120 

6 10 +15 0 0 –120 

1) CETOP = Comité Européen des Transmissions 

Oléohydrauliques et Pneumatiques (European 

Committee for Hydraulic and Pneumatic Transmissions) 

10 18 +18 0 0 –120 

18 30 +21 0 0 –120 


97






Bore Radial internal Bore Radial internal 

diameter clearance diameter clearance 

d Normal d Normal 

over incl. min max over incl. min max 

mm µm mm µm 

Table 

4 


The steel-on-steel rod ends have radial 

internal clearance corresponding to the 

Normal clearance values quoted in 

ISO 12240-4:1998 which are given in 

Table 4 . 

12 16 68 6 5 50 

12 20 20 82 6 10 7 60 

20 35 25 100 10 18 8 75 

35 60 30 120 18 30 10 90 

60 90 36 142 

90 140 42 165 

140 240 50 192 


Materials 

The materials used for the manufacture 

of SKF rod ends requiring maintenance 

are listed in Table 5 . 

Details of the materials used for the 

steel-on-steel spherical plain bearings 

incorporated in SKF rod ends will be 

found under the heading “Materials” 

on page 61. 

The bearings incorporated in the 

steel-on-bronze rod ends have an 

outer ring of tin bronze. The inner ring 

is of carbon chromium steel and is 

hardened, ground and polished. 


range 

The operating temperature range for 

the rod ends requiring maintenance 

depends on the rod end, the bearing 

incorporated, the bearing seals and 

the grease used for lubrication. The 

actual limits are given in Table 6 . 

Rod end housing materials 

Table 

Series Size Material Material No. 

5 

SA(A) 6 to 80 Heat treatable steel C45V 1.0503 

zinc coated and chromatized 

SI(A) 6 to 80 Heat treatable steel C45V 1.0503 


SC 25 to 80 Construction steel S 355 J2G3 (St 52-3 N) 1.0570 

SCF 20 to 80 Construction steel S 355 J2G3 (St 52-3 N) 1.0570 

SIQG 12 to 50 Heat treatable steel C45N 1.0503 

63 to 200 Spheroidal graphite cast iron GGG40 – 

SIJ 12 to 50 Heat treatable steel C45N 1.0503 


SIR 20 to 50 Heat treatable steel C45N 1.0503 


SAKAC 5 to 12 Automatic steel 9 SMnPb 28 K 1.0718 


14 to 30 Heat treatable steel C35N 1.0501 


SIKAC 5 to 12 Automatic steel 9 SMnPb 28 K 1.0718 


14 to 30 Heat treatable steel C35N 1.0501 


Note 

The load carrying capacity of rod 

ends is reduced at temperatures 

above +100 °C. For temperatures 

below 0 °C, the fracture toughness 

of the rod end material must be 

taken into consideration. 

98 





Fatigue strength 

In all applications where a rod end is 

subjected to loads which vary in magnitude 

or are alternating, or where the 

failure of a rod end would be dangerous, 

it is advisable to check that the 

selected rod end has a suitable fatigue 

strength. 

Relubrication facilities 

All SKF rod ends requiring maintenance, 

with the exception of steel-onsteel 

rod ends of series SA .. E and 

SI .. E and the steel-on-bronze rod 

ends of size 5 are provided with a 

grease nipple or hole in the rod end 

housing. The type and design of the 

relubrication facilities in the rod end 

housing are shown in Table 7 . 

Series Permissible operating Reduced load 

temperature range 1) carrying capacity 

from incl. from 

– °C °C 


SA .. E(S) –50 +300 +100 

SA(A) .. ES-2RS –30 +130 +100 

SI .. E(S) –50 +300 +100 

SI(A) .. ES-2RS –30 +130 +100 

SIQG .. ES –50 +300 +100 

SIJ .. ES –50 +300 +100 

SIR .. ES –50 +300 +100 

SC .. ES –50 +300 +100 

SCF .. ES –50 +300 +100 

Steel-on-bronze 

SAKAC .. M –30 +180 +100 

SIKAC .. M(VZ019) –30 +180 +100 

Table 

6 

1) NB. The permissible operating temperature range of the grease used should not be exceeded 

Permissible operating temperature range 

Relubrication facilities 

Series Size Grease nipple Design 

to DIN/ISO 

Table 

7 

3.5 

SA .. ES 15 .. 20 Lubrication hole 

SI .. ES 15 .. 20 2,5 mm diameter 

SIJ .. ES 16 .. 20 

SA(A) .. ES-2RS 25 ..80 Lubrication nipple to 

SI(A) .. ES-2RS 25 ..80 DIN 71412:1987, Form A 

SIJ .. ES 25 .. 100 ISO 3799:1976 

SIR .. ES 25 .. 120 

SIQG .. ES 12 .. 200 

SC .. ES 25 .. 80 

SCF .. ES 20 .. 80 

SAKAC .. M 6 .. 30 Lubrication nipple to 

SIKAC .. M 6 .. 30 DIN 3405:1986 

Form D 


99



Page ................ 4 Page .............. 16 Steel-on-steel rod ends 

with female thread 

d 6 – 80 mm 

B 

C1 

α 

d 2 

dk 

d 

r 1 

l 3 

l 5 

l 7 

h 1 

l 4 

G 

w 

d 4 

SI .. E 

Principal dimensions Angle Basic load ratings Mass Designations 

of tilt dynamic static Rod end with 

right-hand left-hand 

d d 2 G B C 1 h 1 α C C 0 thread thread 

max 6H max 


6 22 M 6 6 4,5 30 13 3,4 8,15 0,023 SI 6 E SIL 6 E 

8 25 M 8 8 6,5 36 15 5,5 12,9 0,036 SI 8 E SIL 8 E 

10 30 M 10 9 7,5 43 12 8,15 19 0,065 SI 10 E SIL 10 E 

12 35 M 12 10 8,5 50 10 10,8 25,5 0,11 SI 12 E SIL 12 E 

15 41 M 14 12 10,5 61 8 17 37,5 0,18 SI 15 ES SIL 15 ES 

17 47 M 16 14 11,5 67 10 21,2 44 0,25 SI 17 ES SIL 17 ES 

20 54 M 20×1,5 16 13,5 77 9 30 57 0,36 SI 20 ES SIL 20 ES 

25 65 M 24×2 20 18 94 7 48 90 0,65 SI 25 ES SIL 25 ES 

30 75 M 30×2 22 20 110 6 62 116 1,00 SI 30 ES SIL 30 ES 

35 84 M 36×3 25 22 130 6 80 134 1,40 SI 35 ES-2RS SIL 35 ES-2RS 

40 94 M 39×3 28 24 142 6 100 166 2,20 SIA 40 ES-2RS SILA 40 ES-2RS 

94 M 42×3 28 24 145 6 100 166 2,30 SI 40 ES-2RS SIL 40 ES-2RS 











100 




Page ................ 4 Page .............. 16 

SI .. ES 

SIA .. ES-2RS 

Dimensions 

d dk d4 l3 l4 l5 l7 r1 w 

≈ min max ≈ min min h14 

mm 

6 10 11 11 43 8 10 0,3 9 

8 13 13 15 50 9 11 0,3 11 

10 16 16 15 60 11 13 0,3 14 

12 18 19 18 69 12 17 0,3 17 

15 22 22 21 83 14 19 0,3 19 

17 25 25 24 92 15 22 0,3 22 

20 29 28 30 106 16 24 0,3 24 

25 35,5 35 36 128 18 30 0,6 30 

3.5 

30 40,7 42 45 149 19 34 0,6 36 

35 47 49 60 174 25 40 0,6 41 

40 53 58 65 191 25 46 0,6 50 

53 58 65 194 25 46 0,6 50 

45 60 65 65 199 30 50 0,6 55 

60 65 65 219 30 50 0,6 55 

50 66 70 68 219 30 58 0,6 60 

66 70 68 254 30 58 0,6 60 

60 80 82 70 246 35 73 1 70 

80 82 70 296 35 73 1 70 

70 92 92 80 284 40 85 1 80 

92 92 80 349 40 85 1 80 

80 105 105 85 324 45 98 1 90 

105 105 85 389 45 98 1 90 


101



Page ................ 4 Page .............. 16 Steel-on-steel rod ends with female 

thread for hydraulic cylinders 

d 12 – 200 mm 

B α 

C 

d 2 

1 

dk 

d 

r 1 

l 4 

l 7 

h1 

l 3 

A 

B 

N 1 

G 

d4 

SIJ .. ES 

N 

A - B 




d d 2 G B C 1 h 1 α C C 0 thread thread1) 

max 6H max 


12 40 M 10×1,25 10 8 42 3 10,8 21,2 0,14 SIJ 12 E SILJ 12 E 

33 M 12×1,25 12 11 38 4 10,8 22 0,11 SIQG 12 ESA SILQG 12 ESA 

16 45 M 12×1,25 14 11 48 3 21,2 23,5 0,25 SIJ 16 ES SILJ 16 ES 

41 M 14×1,5 16 15 44 4 17,6 32,5 0,21 SIQG 16 ES SILQG 16 ES 

20 55 M 14×1,5 16 13 58 3 30 51 0,40 SIJ 20 ES SILJ 20 ES 

50 M 16×1,5 20 19 52 4 30 43 0,40 SIQG 20 ES SILQG 20 ES 

25 65 M 16×1,5 20 17 68 3 48 73,5 0,68 SIJ 25 ES SILJ 25 ES 

58 M 16×1,5 20 23,5 50 7 48 52 0,49 SIR 25 ES SILR 25 ES 

62 M 20×1,5 25 23 65 4 48 69,5 0,66 SIQG 25 ES SILQG 25 ES 

30 80 M 20×1,5 22 19 85 3 62 112 1,35 SIJ 30 ES SILJ 30 ES 

66 M 22×1,5 22 28,5 60 6 62 78 0,77 SIR 30 ES SILR 30 ES 

32 76 M 27×2 32 29 80 4 65,5 100 1,20 SIQG 32 ES SILQG 32 ES 

35 80 M 28×1,5 25 30,5 70 6 80 118 1,20 SIR 35 ES SILR 35 ES 

40 100 M 27×2 28 23 105 3 100 146 2,40 SIJ 40 ES SILJ 40 ES 

96 M 35×1,5 28 35,5 85 7 100 200 2,10 SIR 40 ES SILR 40 ES 

97 M 33×2 40 34 97 4 100 176 2,00 SIQG 40 ES SILQG 40 ES 

50 122 M 33×2 35 30 130 3 156 216 3,80 SIJ 50 ES SILJ 50 ES 

118 M 45×1,5 35 40,5 105 6 156 280 3,60 SIR 50 ES SILR 50 ES 


60 160 M 42×2 44 38 150 3 245 405 8,50 SIJ 60 ES SILJ 60 ES 

132 M 58×1,5 44 50,5 130 6 245 325 6,00 SIR 60 ES SILR 60 ES 

63 142 M 48×2 63 55 140 4 255 375 6,80 SIQG 63 ES SILQG 63 ES 

70 157 M 65×1,5 49 55,5 150 6 315 450 9,40 SIR 70 ES SILR 70 ES 

80 205 M 48×2 55 47 185 3 400 610 14,5 SIJ 80 ES SILJ 80 ES 

179 M 80×2 55 60,5 170 6 400 560 13,0 SIR 80 ES SILR 80 ES 


100 240 M 64×3 70 57 240 3 610 780 29,5 SIJ 100 ES SILJ 100 ES 

233 M 110×2 70 70,5 235 7 610 950 30,0 SIR 100 ES SILR 100 ES 


120 342 M 130×3 85 90,5 310 6 950 2 450 84,0 SIR 120 ES SILR 120 ES 

125 290 M 100×3 125 105 260 4 950 1 430 43,0 SIQG 125 ES SILQG 125 ES 

160 346 M 125×4 160 132 310 4 1 370 2 200 80,0 SIQG 160 ES SILQG 160 ES 

200 460 M 160×4 200 164 390 4 2 120 3 400 165 SIQG 200 ES SILQG 200 ES 

1) Please check availability of rod ends with left-hand thread 

102 




Page ................ 4 Page .............. 16 

C 1 

r 1 

B 

α 

d 2 

B 

C 1 

α 

d 2 

dk 

d 

l 7 

h 1 

l 4 

dk 

d 

r 1 

l 7 

h 1 

l 4 

l 3 

l 3 

G 

d4 

N 

G 

d4 

N 

SIR .. ES 

SIQG .. ES 

Dimensions 

Cylinder screw 

with internal hexagon 

(ISO 4762:1998) 

d d k d 4 l 3 l 4 l 7 N N 1 r 1 Size Tightening 

max min max min max max min torque 

mm – Nm 

12 18 17 15 62 16 40 13 0,3 M 6 9,5 

18 17 17 55,5 13 33 11 0,3 M 5 5,5 

16 25 21 17 70,5 20 45 13 0,3 M 6 9,5 

23 22,5 19 64,5 18 41 17 0,3 M 6 9,5 

20 29 25 19 85,5 25 55 17 0,3 M 8 23 

29 26,5 23 77,5 21 48 21 0,3 M 8 23 

25 35,5 30 23 100,5 30 62 17 0,6 M 8 23 

35,5 26,5 17 81 27 46 22 0,6 M 8 23 

35,5 32 29 97 26 55 21 0,6 M 8 23 

30 40,7 36 29 125 35 80 19 0,6 M 10 46 

40,7 34 23 95 29 50 27 0,6 M 8 23 

32 43 40 37 120 31 67 24 0,6 M 10 46 

35 47 42 29 113 37 66 29 0,6 M 10 46 

40 53 45 37 155 45 90 23 0,6 M 10 46 

53 51 36 136 44 76 34 0,6 M 10 46 

53 49 46 147 40 81 28 0,6 M 10 46 

50 66 55 46 192,5 58 105 30 0,6 M 12 79 

66 63,5 46 169 54 90 38 0,6 M 12 79 

66 60,5 57 181 49 97 34 0,6 M 12 79 

60 80 68 57 230 68 134 38 1 M 16 195 

80 77,5 59 201 64 120 47 1 M 16 195 

63 83 72,5 64 213 61 116 40 1 M 16 195 

70 92 89 66 234 74 130 52 1 M 16 195 

80 105 90 64 287,5 92 156 47 1 M 20 390 

105 109 81 267 79 160 57 1 M 20 390 

105 93 86 272 77 150 50 1 M 20 390 

100 130 110 86 360 116 190 57 1 M 24 670 

130 142 111 362 103 200 67 1 M 24 670 

130 114 96 324 97 180 65 1 M 24 670 

120 160 177 135 491 138 257 86 1 M 24 670 

125 160 139 113 407 118 202 75 1 M 24 670 

160 200 170 126 490 148 252 85 1 M 24 670 

200 250 221 161 623 193 323 106 1,1 M 30 1 350 

3.5 


103



Page ................ 4 Page .............. 16 Steel-on-steel rod ends 

with male thread 

d 6 – 80 mm 

B 

C1 

α 

d 2 

dk 

d 

r 1 

l 7 

h 

l 2 

l 1 

G 

SA .. E 




d d 2 G B C 1 h α C C 0 thread thread 

max 6g max 


6 22 M 6 6 4,5 36 13 3,4 8,15 0,017 SA 6 E SAL 6 E 

8 25 M 8 8 6,5 42 15 5,5 12,9 0,029 SA 8 E SAL 8 E 

10 30 M 10 9 7,5 48 12 8,15 18,3 0,053 SA 10 E SAL 10 E 

12 35 M 12 10 8,5 54 10 10,8 24,5 0,078 SA 12 E SAL 12 E 

15 41 M 14 12 10,5 63 8 17 28 0,13 SA 15 ES SAL 15 ES 

17 47 M 16 14 11,5 69 10 21,2 31 0,19 SA 17 ES SAL 17 ES 

20 54 M 20×1,5 16 13,5 78 9 30 42,5 0,32 SA 20 ES SAL 20 ES 

25 65 M 24×2 20 18 94 7 48 78 0,53 SA 25 ES SAL 25 ES 

30 75 M 30×2 22 20 110 6 62 81,5 0,90 SA 30 ES SAL 30 ES 

35 84 M 36×3 25 22 130 6 80 110 1,30 SA 35 ES-2RS SAL 35 ES-2RS 

40 94 M 39×3 28 24 150 6 100 140 1,85 SAA 40 ES-2RS SALA 40 ES-2RS 

94 M 42×3 28 24 145 6 100 140 1,90 SA 40 ES-2RS SAL 40 ES-2RS 











104 




Page ................ 4 Page .............. 16 

SA .. ES 

SAA .. ES-2RS 

Dimensions 

d d k l 1 l 2 l 7 r 1 

min max min min 

mm 

6 10 16 49 10 0,3 

8 13 21 56 11 0,3 

10 16 26 65 13 0,3 

12 18 28 73 17 0,3 

15 22 34 85 19 0,3 

17 25 36 94 22 0,3 

20 29 43 107 24 0,3 

25 35,5 53 128 30 0,6 

3.5 

30 40,7 65 149 34 0,6 

35 47 82 174 40 0,6 

40 53 86 199 46 0,6 

53 90 194 46 0,6 

45 60 92 217 50 0,6 

60 95 219 50 0,6 

50 66 104 244 58 0,6 

66 110 254 58 0,6 

60 80 115 281 73 1 

80 120 296 73 1 

70 92 125 319 85 1 

92 132 349 85 1 

80 105 140 364 98 1 

105 147 389 98 1 


105



Page ................ 4 Page .............. 16 Steel-on-steel rod ends with 

cylindrical section welding shank 

d 20 – 80 mm 

dk 

d 

B 

C1 

d5 

r 1 

α 

r 2 

d 2 

d6 

45° 

l 7 h 2 

6 

l 6 



d d 2 B C 1 h 2 α C C 0 

max max 


20 54 16 13,5 38 9 30 46,5 0,20 SC 20 ES 

25 65 20 18 45 7 48 73,5 0,45 SC 25 ES 

30 75 22 20 51 6 62 96,5 0,65 SC 30 ES 

35 84 25 22 61 6 80 112 1,00 SC 35 ES 

40 94 28 24 69 7 100 134 1,30 SC 40 ES 

45 104 32 28 77 7 127 180 1,90 SC 45 ES 

50 114 35 31 88 6 156 220 2,50 SC 50 ES 

60 137 44 39 100 6 245 335 4,60 SC 60 ES 

70 162 49 43 115 6 315 455 6,80 SC 70 ES 

80 182 55 48 141 6 400 550 9,70 SC 80 ES 

106 




Page ................ 4 Page .............. 16 

Dimensions 

d d k d 5 d 6 l 6 l 7 r 1 r 2 

max max min min 

mm 

20 29 29 4 66 24 0,3 2 

25 35,5 35 4 78 30 0,6 3 

30 40,7 42 4 89 34 0,6 3 

35 47 49 4 104 40 0,6 3 

40 53 54 4 118 46 0,6 4 

45 60 60 6 132 50 0,6 4 

50 66 64 6 150 58 0,6 4 

60 80 72 6 173 73 1 4 

70 92 82 6 199 85 1 5 

80 105 97 6 237 98 1 5 

3.5 


107



Page ................ 4 Page .............. 16 Steel-on-steel rod ends with 

rectangualar section welding shank 

d 20 – 80 mm 

C1 

B 

α 

d 2 

dk 

d 

r 1 

h 2 

l 6 



d d 2 B C 1 h 2 α C C 0 

max max js13 


20 51,5 16 20 38 9 30 63 0,35 SCF 20 ES 

25 56,5 20 24 45 7 48 65,5 0,53 SCF 25 ES 

30 66,5 22 29 51 6 62 110 0,87 SCF 30 ES 

35 85 25 31 61 6 80 183 1,55 SCF 35 ES 

40 102 28 36,5 69 7 100 285 2,45 SCF 40 ES 

45 112 32 41,5 77 7 127 360 3,40 SCF 45 ES 

50 125,5 35 41,5 88 6 156 415 4,45 SCF 50 ES 

60 142,5 44 51,5 100 6 245 530 7,00 SCF 60 ES 

70 166,5 49 57 115 6 315 680 10,0 SCF 70 ES 

80 182,5 55 62 141 6 400 750 15,0 SCF 80 ES 

108 




Page ................ 4 Page .............. 16 

Dimensions 

d d k l 6 r 1 

max min 

mm 

20 29 64 0,3 

25 35,5 73,5 0,6 

30 40,7 85 0,6 

35 47 103,5 0,6 

40 53 120 0,6 

45 60 133 0,6 

50 66 151 0,6 

60 80 171,5 1 

70 92 198,5 1 

80 105 232,5 1 

3.5 


109



Page ................ 4 Page .............. 16 Steel-on-bronze rod ends 

with female thread 

d 5 – 30 mm 

B 

C1 

α 

d 2 

dk 

d 

r 1 

l7 

h 

l 4 

1 

l 3 

G 

w 

d 3 

d 4 



right-hand 

left-hand 


max 6H 

max 


5 19 M 5 8 6 27 13 3,25 5,4 0,017 SIKAC 5 M 1) SILKAC 5 M 1) 

6 21 M 6 9 6,75 30 13 4,3 5,4 0,025 SIKAC 6 M SILKAC 6 M 

8 25 M 8 12 9 36 14 7,2 9,15 0,043 SIKAC 8 M SILKAC 8 M 

10 29 M 10 14 10,5 43 13 10 12,2 0,072 SIKAC 10 M SILKAC 10 M 

29 M 10×1,25 14 10,5 43 13 10 12,2 0,072 SIKAC 10 M/VZ019 – 

12 33 M 12 16 12 50 13 13,4 14 0,11 SIKAC 12 M SILKAC 12 M 

33 M 12×1,25 16 12 50 13 13,4 14 0,11 SIKAC 12 M/VZ019 – 

14 37 M 14 19 13,5 57 16 17 20,4 0,16 SIKAC 14 M SILKAC 14 M 

16 43 M 16 21 15 64 15 21,6 29 0,22 SIKAC 16 M SILKAC 16 M 

43 M 16×1,5 21 15 64 15 21,6 29 0,22 SIKAC 16 M/VZ019 – 

18 47 M 18×1,5 23 16,5 71 15 26 35,5 0,30 SIKAC 18 M SILKAC 18 M 

20 51 M 20×1,5 25 18 77 14 31,5 35,5 0,40 SIKAC 20 M SILKAC 20 M 

22 55 M 22×1,5 28 20 84 15 38 45 0,50 SIKAC 22 M SILKAC 22 M 

25 61 M 24×2 31 22 94 15 47,5 53 0,65 SIKAC 25 M SILKAC 25 M 

30 71 M 30×2 37 25 110 17 64 69,5 1,15 SIKAC 30 M SILKAC 30 M 

1) 

Without lubrication nipple 

110 




Page ................ 4 Page .............. 16 

Dimensions 

d d k d 3 d 4 l 3 l 4 l 5 l 7 r 1 w 

≈ max min max ≈ min min h14 

mm 

5 11,1 9 12 8 38 4 9 0,3 9 

6 12,7 10 14 9 42 5 10 0,3 11 

8 15,8 12,5 17 12 50 5 12 0,3 14 

10 19 15 20 15 59 6,5 14 0,3 17 

19 15 20 15 59 6,5 14 0,3 17 

12 22,2 17,5 23 18 68 6,5 16 0,3 19 

22,2 17,5 23 18 68 6,5 16 0,3 19 

14 25,4 20 27 21 77 8 18 0,3 22 

16 28,5 22 29 24 87 8 21 0,3 22 

28,5 22 29 24 87 8 21 0,3 22 

3.5 

18 31,7 25 32 27 96 10 23 0,3 27 

20 34,9 27,5 37 30 105 10 25 0,3 30 

22 38,1 30 40 33 114 12 27 0,3 32 

25 42,8 33,5 44 36 127 12 30 0,3 36 

30 50,8 40 52 45 148 15 35 0,3 41 


111



Page ................ 4 Page .............. 16 Steel-on-bronze rod ends 

with male thread 

d 5 – 30 mm 

B 

C1 

α 

d 2 

dk 

d 

r 1 

l 2 

h 

l 1 

G 





max 6g max 


5 19 M 5 8 6 33 13 3,25 4,8 0,013 SAKAC 5 M 1) SALKAC 5 M 1) 

6 21 M 6 9 6,75 36 13 4,3 4,8 0,020 SAKAC 6 M SALKAC 6 M 

8 25 M 8 12 9 42 14 7,2 8 0,032 SAKAC 8 M SALKAC 8 M 

10 29 M 10 14 10,5 48 13 10 10,8 0,054 SAKAC 10 M SALKAC 10 M 

12 33 M 12 16 12 54 13 12,2 12,2 0,085 SAKAC 12 M SALKAC 12 M 

14 37 M 14 19 13,5 60 16 17 17,3 0,13 SAKAC 14 M SALKAC 14 M 

16 43 M 16 21 15 66 15 21,6 23,2 0,19 SAKAC 16 M SALKAC 16 M 

18 47 M 18×1,5 23 16,5 72 15 26 29 0,26 SAKAC 18 M SALKAC 18 M 

20 51 M 20×1,5 25 18 78 14 29 29 0,34 SAKAC 20 M SALKAC 20 M 

22 55 M 22×1,5 28 20 84 15 38 39 0,44 SAKAC 22 M SALKAC 22 M 

25 61 M 24×2 31 22 94 15 46,5 46,5 0,60 SAKAC 25 M SALKAC 25 M 

30 71 M 30×2 37 25 110 17 61 61 1,05 SAKAC 30 M SALKAC 30 M 

1) 

Without lubrication nipple 

112 




Page ................ 4 Page .............. 16 

Dimensions 

d d k l 1 l 2 r 1 

min max min 

mm 

5 11,1 19 44 0,3 

6 12,7 21 48 0,3 

8 15,8 25 56 0,3 

10 19 28 64 0,3 

12 22,2 32 72 0,3 

14 25,4 36 80 0,3 

16 28,5 37 89 0,3 

18 31,7 41 97 0,3 

3.5 

20 34,9 45 106 0,3 

22 38,1 48 114 0,3 

25 42,8 55 127 0,3 

30 50,8 66 148 0,3 


113



Page ................ 4 Page .............. 16 Maintenance-free rod ends 


114 





SKF maintenance-free rod ends are 

produced with three different sliding 

contact surface combinations. 

The rod ends with the sliding contact 

surface combinations steel/sinter bronze 

composite (➔ fig 1 ) and steel/PTFE 

fabric (➔ fig 2 ) comprise a rod end 

housing and a standard spherical plain 

bearing, the outer ring of which is held 

in position axially. 

The rod ends with the sliding contact 

surface combination steel/PTFE composite 

(➔ fig 3 ) consist of a rod end 

housing and a spherical plain bearing 

inner ring. Between the housing and 

the inner ring, a sliding layer of glass 

fibre reinforced plastic containing 

PTFE is injection moulded in situ. 

Maintenance-free rod end, steel/sinter 


1 

Fig 

2 

Maintenance-free rod end, steel/PTFE 

fabric 

Fig 

3 

3.6 

Maintenance-free rod end, steel/PTFE 

composite 


115




Dimensions 

The dimensions of the maintenancefree 

rod ends conform to ISO 12240- 

4:1998. Those rod ends which carry 

the designation suffix /VZ019 have a 

thread which deviates from that specified 

in ISO 12240-4 but is in accordance 

with the CETOP 1) recommendation 

RP 103 P and ISO 8139:1991. 

The female and male threads of 

SKF rod ends are in accordance with 

ISO 965-1:1998. 

Tolerances 

The tolerances of SKF rod ends are in 

accordance with the tolerances specified 

in ISO 12240-4:1998. The actual 

tolerance values are given in Table 1 . 

The symbols used in Table 1 are 

explained in the following. 






Internal clearance, preload 

SKF maintenance-free rod ends, because 

of their design, have a radial internal 

clearance but may also have a 

light preload. Therefore, Tables 2 and 

3 show maximum values for the radial 

internal clearance as well as for 

the friction torque in the circumferential 

direction caused by preload. 

Bore Series Series 

diameter SA(A) and SI(A) SAKB and SIKB 

d ∆ dmp ∆ Bs ∆ dmp ∆ Bs 



Table 

6 0 –8 0 –120 +12 0 0 –120 

6 10 0 –8 0 –120 +15 0 0 –120 

10 18 0 –8 0 –120 +18 0 0 –120 

18 30 0 –10 0 –120 – – – – 

30 50 0 –12 0 –120 – – – – 

50 80 0 –15 0 –150 – – – – 

Bore Radial Friction 

diameter internal torque 

d 

clearance 

over incl. max max 

mm µm Nm 

12 28 0,15 

12 20 35 0,25 

20 30 44 0,40 

30 35 50 2,5 

35 40 60 2,5 

40 45 60 3,5 

50 60 60 4 

60 70 72 5 

Table 

1 

2 

Tolerances for 

maintenance-free 

rod end inner 

rings 

Radial internal 

clearance and 

friction torque for 

steel/sinter bronze 

composite and 


rod ends 

Series SA(A) and 

SI(A) 

Bore Radial Friction 

diameter internal torque 

d 

clearance 

max max 

mm µm Nm 

Table 

3 

Radial internal 

clearance and 

friction torque for 


rod ends 

Series SAKB and 

SIKB 

5 50 0,20 

6 50 0,25 

8 50 0,30 

10 75 0,40 

12 75 0,50 

14 75 0,60 

16 75 0,70 

18 85 0,80 

20 100 1 

1) CETOP = Comité Européen des Transmissions 

Oléohydrauliques et Pneumatiques (European 

Committee for Hydraulic and Pneumatic Transmissions) 

116 





Rod end housing 

materials 

Permissible 

operating 

temperature range 

Series Size Material Material No. 

SA(A) 6 .. 80 Heat treatable steel C45V 1.0503 

SI(A) 


SAKB 5 .. 12 Automatic steel 

9 SMnPb 28 K 1.0718 

zinc coated and 

chromatized 

SIKB 14 .. 20 Heat treatable steel C35N 1.0501 

zinc coated and 

chromatized 

Table 

Series Permissible operating Reduced 

temperature range load carrying 

from incl. capacity 

from 

– °C °C 


SA .. C –50 +150 +80 

SI .. C 


SA(A) .. TXE-2LS –30 +130 +60 

SI(A) .. TXE-2LS 

Steel/PTFE composite 

SAKB .. F –40 +75 +50 

SIKB .. F 

SIKB .. F/VZ019 

Table 

4 

5 

Materials 

The materials used for the rod end 

housings of SKF maintenance-free rod 

ends are listed in Table 4 . The right is 

reserved to make changes dictated by 

technical developments. 

Details of the materials used for the 

maintenance-free spherical plain bearings 

incorporated in the rod ends will 

be found in Matrix 1 , page 73. 

The inner rings of rod ends with the 

sliding contact surface combination 

steel/PTFE composite are of bearing 

steel which is hardened and ground 

and the sliding contact surface is hard 

chromium plated. The sliding layer of 

these bearings consists of a glass 

fibre reinforced polymer containing 

PTFE. 


range 

The permissible operating temperature 

range for SKF maintenance-free rod 

ends is governed by the rod end housing, 

the spherical plain bearing incorporated 

and the bearing seals. The 

ranges are given in Table 5 . 

Fatigue strength 

In applications where the rod end is 

subjected to loads of alternating magnitude 

or direction, or where rod end 

failure could be dangerous, it is necessary 

to check the fatigue strength of 

the rod end. 

3.6 


117



Page ................ 4 Page .............. 16 Maintenance-free rod ends with 

female thread, with sliding contact 

surface combination steel/sinter 


d 6 – 30 mm 

B α 

C 

1 

d 2 

dk 

d 

r 1 

l 3 

l 5 

l 7 

h 1 

l 4 

G 

w 

d 4 





max 6H max 


6 22 M 6 6 4,5 30 13 3,6 8,15 0,023 SI 6 C SIL 6 C 

8 25 M 8 8 6,5 36 15 5,8 12,9 0,036 SI 8 C SIL 8 C 

10 30 M 10 9 7,5 43 12 8,65 19 0,065 SI 10 C SIL 10 C 

12 35 M 12 10 8,5 50 10 11,4 25,5 0,11 SI 12 C SIL 12 C 

15 41 M 14 12 10,5 61 8 18 37,5 0,18 SI 15 C SIL 15 C 

17 47 M 16 14 11,5 67 10 22,4 46,5 0,25 SI 17 C SIL 17 C 

20 54 M 20×1,5 16 13,5 77 9 31,5 57 0,35 SI 20 C SIL 20 C 

25 65 M 24×2 20 18 94 7 51 90 0,65 SI 25 C SIL 25 C 

30 75 M 30×2 22 20 110 6 65,5 118 1,05 SI 30 C SIL 30 C 

118 




Page ................ 4 Page .............. 16 

Dimensions 

d d k d 4 l 3 l 4 l 5 l 7 r 1 w 


mm 

6 10 11 11 43 8 10 0,3 9 

8 13 13 15 50 9 11 0,3 11 

10 16 16 15 60 11 13 0,3 14 

12 18 19 18 69 12 17 0,3 17 

15 22 22 21 83 14 19 0,3 19 

17 25 25 24 92 15 22 0,3 22 

20 29 28 30 106 16 24 0,3 24 

25 35,5 35 36 128 18 30 0,6 30 

30 40,7 42 45 149 19 34 0,6 36 

3.6 


119




male thread, with sliding contact surface 


composite 

d 6 – 30 mm 

B α 

C 

d 2 

1 

dk 

d 

r 1 

l 7 

l 2 

h 

l 1 

G 

Principal dimensions Angle Basic load rating Mass Designations 




max 6g 

max 


6 22 M 6 6 4,5 36 13 3,6 8,15 0,017 SA 6 C SAL 6 C 

8 25 M 8 8 6,5 42 15 5,85 12,9 0,030 SA 8 C SAL 8 C 

10 30 M 10 9 7,5 48 12 8,65 18,3 0,053 SA 10 C SAL 10 C 

12 35 M 12 10 8,5 54 10 11,4 24,5 0,078 SA 12 C SAL 12 C 

15 41 M 14 12 10,5 63 8 18 34,5 0,13 SA 15 C SAL 15 C 

17 47 M 16 14 11,5 69 10 22,4 42,5 0,19 SA 17 C SAL 17 C 

20 54 M 20×1,5 16 13,5 78 9 31,5 51 0,32 SA 20 C SAL 20 C 

25 65 M 24×2 20 18 94 7 51 78 0,57 SA 25 C SAL 25 C 

30 75 M 30×2 22 20 110 6 65,5 104 0,90 SA 30 C SAL 30 C 

120 




Page ................ 4 Page .............. 16 

Dimensions 

d d k l 1 l 2 l 7 r 1 


mm 

6 10 16 49 10 0,3 

8 13 21 56 11 0,3 

10 16 26 65 13 0,3 

12 18 28 73 17 0,3 

15 22 34 85 19 0,3 

17 25 36 94 22 0,3 

20 29 43 107 24 0,3 

25 35,5 53 128 30 0,6 

30 40,7 65 149 34 0,6 

3.6 


121




female thread, with sliding contact 


fabric 

d 35 – 70 mm 

B 

α 

C 

1 

d 2 

dk 

d 

r 1 

l 3 

l 5 

l 7 

h 1 

l 4 

G 

w 

d 4 





max 6H max 


35 84 M 36×3 25 22 130 6 224 134 1,40 SI 35 TXE-2LS SIL 35 TXE-2LS 

40 94 M 39×3 28 24 142 7 280 166 2,20 SIA 40 TXE-2LS SILA 40 TXE-2LS 

94 M 42×3 28 24 145 7 280 166 2,30 SI 40 TXE-2LS SIL 40 TXE-2LS 







70 162 M 72×4 49 43 265 6 880 530 10,5 SI 70 TXE-2LS SIL 70 TXE-2LS 

80 182 M 80×4 55 48 295 6 1 140 655 19,0 SI 80 TXE-2LS SIL 80 TXE-2LS 

122 




Page ................ 4 Page .............. 16 

Dimensions 

d d k d 4 l 3 l 4 l 5 l 7 r 1 w 


mm 

35 47 49 60 174 25 40 0,6 41 

40 53 58 65 191 25 46 0,6 50 

53 58 65 194 25 46 0,6 50 

45 60 65 65 199 30 50 0,6 55 

60 65 65 219 30 50 0,6 55 

50 66 70 68 246 30 58 0,6 60 

66 70 68 254 30 58 0,6 60 

60 80 82 70 246 35 73 1 70 

80 82 70 296 35 73 1 70 

70 92 92 80 349 40 85 1 80 

80 105 105 85 389 40 98 1 90 

3.6 


123




male thread, with sliding contact surface 


d 35 – 70 mm 

B 

C1 

α 

d 2 

dk 

d 

r 1 

l 7 

l 2 

h 

l 1 

G 






max 6g max 


35 84 M 36×3 25 22 130 6 224 110 1,30 SA 35 TXE-2LS SAL 35 TXE-2LS 

40 94 M 39×3 28 24 150 6 280 140 1,85 SAA 40 TXE-2LS SALA 40 TXE-2LS 

94 M 42×3 28 24 145 6 280 140 1,90 SA 40 TXE-2LS SAL 40 TXE-2LS 







70 162 M 72×4 49 43 265 6 880 490 10,0 SA 70 TXE-2LS SAL 70 TXE-2LS 

80 182 M 80×4 55 48 295 5 1 140 585 14,5 SA 80 TXE-2LS SAL 80 TXE-2LS 

124 




Page ................ 4 Page .............. 16 

Dimensions 

d d k l 1 l 2 l 7 r 1 


mm 

35 47 82 174 40 0,6 

40 53 86 199 46 0,6 

53 90 194 46 0,6 

45 60 92 217 50 0,6 

60 95 219 50 0,6 

50 66 104 244 58 0,6 

66 110 254 58 0,6 

60 80 115 281 73 1 

80 120 296 73 1 

70 92 132 349 85 1 

80 105 147 389 98 1 

3.6 


125




female, thread with sliding contact 


composite 

d 5 – 20 mm 

B 

C α 

d 2 

1 

dk 

d 

r 1 

l 7 

h 

l 4 

1 

l 3 

G 

w 

l 5 

d 3 

d 4 






max 6H 

max 


5 19 M 5 8 6 27 13 3,25 5,3 0,019 SIKB 5 F SILKB 5 F 

6 21 M 6 9 6,75 30 13 4,25 6,8 0,028 SIKB 6 F SILKB 6 F 

8 25 M 8 12 9 36 14 7,1 11,4 0,047 SIKB 8 F SILKB 8 F 

10 29 M 10 14 10,5 43 13 9,8 14,3 0,079 SIKB 10 F SILKB 10 F 

29 M 10×1,25 14 10,5 43 13 9,8 14,3 0,079 SIKB 10 F/VZ019 – 

12 33 M 12 16 12 50 13 13,2 17 0,12 SIKB 12 F SILKB 12 F 

33 M 12×1,25 16 12 50 13 13,2 17 0,12 SIKB 12 F/VZ019 – 

14 37 M 14 19 13,5 57 16 17 27,5 0,16 SIKB 14 F SILKB 14 F 

16 43 M 16 21 15 64 15 21,4 34,5 0,23 SIKB 16 F SILKB 16 F 

43 M 16×1,5 21 15 64 15 21,4 34,5 0,23 SIKB 16 F/VZ019 – 

18 47 M 18×1,5 23 16,5 71 15 26 41,5 0,33 SIKB 18 F SILKB 18 F 

20 51 M 20×1,5 25 18 77 14 31 50 0,38 SIKB 20 F SILKB 20 F 

126 




Page ................ 4 Page .............. 16 

Dimensions 

d d k d 3 d 4 l 3 l 4 l 5 l 7 r 1 w 

≈ max min max ≈ min min h14 

mm 

5 11,1 9 12 8 37 4 9 0,3 9 

6 12,7 10 14 9 41 5 10 0,3 11 

8 15,8 12,5 17 12 49 5 12 0,3 14 

10 19 15 20 15 58 6,5 14 0,3 17 

19 15 20 15 58 6,5 14 0,3 17 

12 22,2 17,5 23 18 67 6,5 16 0,3 19 

22,2 17,5 23 18 67 6,5 16 0,3 19 

14 25,4 20 27 21 76 8 18 0,3 22 

16 28,5 22 29 24 86 8 21 0,3 22 

28,5 22 29 24 86 8 21 0,3 22 

18 31,7 25 32 27 95 10 23 0,3 27 

20 34,9 27,5 37 30 103 10 25 0,3 30 

3.6 


127




male, thread with sliding contact 


composite 

d 5 – 20 mm 

B 

C 

α 

d 2 

1 

dk 

d 

r 1 

l 2 

h 

l 1 

G 





max 6g 

max 


5 19 M 5 8 6 33 13 3,25 5,3 0,015 SAKB 5 F SALKB 5 F 

6 21 M 6 9 6,75 36 13 4,25 6,8 0,021 SAKB 6 F SALKB 6 F 

8 25 M 8 12 9 42 14 7,1 10 0,035 SAKB 8 F SALKB 8 F 

10 29 M 10 14 10,5 48 13 9,8 12,5 0,059 SAKB 10 F SALKB 10 F 

12 33 M 12 16 12 54 13 13,2 15 0,10 SAKB 12 F SALKB 12 F 

14 37 M 14 19 13,5 60 16 17 25,5 0,13 SAKB 14 F SALKB 14 F 

16 43 M 16 21 15 66 15 21,4 34,5 0,20 SAKB 16 F SALKB 16 F 

18 47 M 18×1,5 23 16,5 72 15 26 41,5 0,26 SAKB 18 F SALKB 18 F 

20 51 M 20×1,5 25 18 78 14 31 50 0,37 SAKB 20 F SALKB 20 F 

128 




Page ................ 4 Page .............. 16 

Dimensions 

d d k l 1 l 2 r 1 

min max min 

mm 

5 11,1 19 44 0,3 

6 12,7 21 48 0,3 

8 15,8 25 56 0,3 

10 19 28 64 0,3 

12 22,2 32 72 0,3 

14 25,4 36 80 0,3 

16 28,5 37 89 0,3 

18 31,7 41 97 0,3 

20 34,9 45 106 0,3 

3.6 


129


Special solutions and related 

SKF products 

Plain bearings for road 

vehicles 

Special applications such as the bearing 

arrangements for centring propeller 

shafts or gear shifts require special 

spherical plain bearings or bearing 

units. SKF has developed appropriate 

products in close cooperation with 

customers and manufactures them in 

large volumes. 

Plain bearings for rail 

vehicles 

The SKF plain bearing range for railway 

vehicles includes bogie swivel 

bearings for trams and heavy duty 

goods wagons as well as spherical 

plain bearings and rod ends for transverse 

stabilizers, tilting mechanisms 

etc. 

130 




and rod ends for the 

aircraft industry 

In the aircraft industry spherical plain 

bearings and rod ends take a prominent 

place as airframe bearings for the 

transmission of rotating, tilting and 

oscillating movements. The SKF specialist 

company for airframe products 

is SARMA, producing spherical plain 

bearings and rod ends for the suspension 

of engines and auxiliary equipment, 

as well those needed for use in 

undercarriages, spoilers, height and 

side rudders, wing flaps etc. 

SARMA manufactures spherical 

plain bearings and rod ends in steel, 

stainless steel and composite materials 

in various sliding contact surface 

combinations: some requiring maintenance 

and some being maintenancefree. 

Airframe control rods and structural 

rods of light alloy, steel, titanium and 

composite materials in a wide variety 

of designs are produced by SARMA 

for a multitude of applications in other 

fields as well as the aircraft industry. 

Direct contact: 

SARMA 

1 avenue Marc Seguin 

Parc Industriel de la Brassière 

F-26241 Saint Vallier sur Rhône 

Cedex 

France 

Telephone: +33 4 75 03 40 40 

Fax: +33 4 75 30 40 00 

3.7 


131


Bushings and flanged 

bushings 

Bushings and flanged bushings have 

been part of the SKF product range 

for more than thirty years and the 

most varied assortment is available 

from stock. A comprehensive range of 

materials is available including the 

following. 

• Solid bronze bushings 

The traditional robust bushings 

• Sintered bronze bushings 

These are impregnated with oil and 

can be operated at high speed 

• Wrapped bronze bushings 

The lubricant pockets allow them to 

function well even in dirty environments 

• PTFE composite bushings 

The low friction enables long periods 

of maintenance-free operation 

• POM composite bushings 

These require little maintenance 

even under arduous conditions 

• Stainless backed composite 

bushings 

These are appropriate for corrosive 

environments 

• PTFE/polyamide bushings 

The cost-favourable, maintenancefree 

bushings for light loads 

• Filament wound bushings 

The maintenance-free bushings for 

extreme conditions 

Because of the great variety of SKF 

bushings they are to be found in all 

branches of industry irrespective of 

whether 

• freedom from maintenance is required, 

or not; 

• lubricants or other media are present, 

or not; 

and where 

• rotational, slewing or linear movement 

must be accommodated. 

See brochure 4741 “SKF bushings”, 

brochure 5110 “Composite 

dry sliding bearings – maintenance-free 

and space-saving” or the 

“SKF Interactive Engineering 

Catalogue” on CD-ROM or online 

at www.skf.com. 

132 



Thrust washers and 

strips 

For thrust bearing arrangements that 

make oscillating or slow rotational 

movements, thrust washers are available 

made of two different triple layer 

composite materials: 

• SKF thrust washers of B material 

(PTFE composite), and 

• SKF thrust washers of M material 

(POM composite). 

The thrust washers are primarily intended 

for applications where axial space 

is extremely limited and where freedom 

from maintenance is required or 

where lubricant starvation can occur. 

SKF also supplies strip of the same 

triple layer composite materials – B 

and M. The strip can be bent, pressed 

or coined to form, for example, linear 

guides with flat, L-shaped or V-shaped 

profiles or many other dry sliding components. 

See brochure 5110 “Composite 

dry sliding bearings – maintenance-free 

and space-saving” or the 

“SKF Interactive Engineering 

Catalogue” on CD-ROM or online 

at www.skf.com. 

3.7 


133


SKF – The knowledge 

engineering company 

The business of the SKF Group consists 

of the design, manufacture and 

marketing of the world’s leading brand 

of rolling bearings, with a global leadership 

position in complementary products 

such as radial seals. SKF also 

holds an increasingly important position 

in the market for linear motion 

products, high precision aerospace 

bearings, machine tool spindles, as 

well as plant maintenance services 

and is an established producer of 

high-quality bearing steel. 

The SKF Group maintains specialized 

businesses to meet the needs of 

the global marketplace. SKF supports 

specific market segments with ongoing 

research and development efforts that 

have led to a growing number of innovations, 

new standards and new 

products. 

SKF Group has global ISO 14001 

environmental certification. Individual 

divisions have been approved for 

quality certification in accordance 

with either ISO 9000 or appropriate 

industry specific standards. 

Some 80 manufacturing sites worldwide 

and sales companies in 70 countries 

make SKF a truly international 

corporation. In addition, our 7 000 

distributor and dealer partners around 

the world, e-business marketplace and 

global distribution system put SKF 

close to customers for the supply of 

both products and services. In essence, 

SKF solutions are available wherever 

and whenever our customers need 

them. 

Overall, the SKF brand now stands 

for more than ever before. It stands for 

the knowledge engineering company 

ready to serve you with world-class 

product competences, intellectual 

resources and the vision to help you 

succeed. 

Harnessing wind power 

The growing industry of wind-generated 

electric power provides an environmentally 

compatible source of electricity. SKF is 

working closely with global industry leaders 

to develop efficient and trouble-free 

turbines, using SKF knowledge to provide 

highly specialized bearings and condition 

monitoring systems to extend equipment 

life in the extreme and often remote environments 

of wind farms. 

Delivering asset efficiency 

optimization 

To optimize efficiency and boost productivity, 

many industrial facilities outsource 

some or all of their maintenance services 

to SKF, often with guaranteed performance 

contracts. Through the specialized 

capabilities and knowledge available from 

Developing a cleaner cleaner 

The electric motor and its bearings are the 

heart of many household appliances. SKF 

works closely with appliance manufacturers 

to improve their product performance, 

cut costs and reduce weight. A recent 

example produced a new generation of 

vacuum cleaners with substantially more 

suction. SKF’s knowledge in small bearing 

technology is also applied to manufacturers 

of power tools and office equipment. 

SKF Reliability Systems, SKF provides a 

comprehensive range of asset efficiency 

services, from maintenance strategies and 

engineering assistance, to operator-driven 

reliability and machine maintenance 

programs. 

134 



Creating a new “cold remedy” 

In the frigid winters of northern China, 

sub-zero temperatures can cause rail car 

wheel assemblies and their bearings to 

seize due to lubrication starvation. SKF 

created a new family of synthetic lubricants 

formulated to retain their lubrication 

viscosity even at these extreme bearing 

temperatures. SKF’s knowledge of lubricants 

and friction are unmatched 

throughout the world. 

Evolving by-wire technology 

SKF has unique expertize and knowledge 

in fast growing by-wire technology, from 

fly-by-wire, to drive-by-wire, to work-bywire. 

SKF pioneered practical fly-by-wire 

technology and is a close working partner 

with all aerospace industry leaders. 

As an example, virtually all aircraft of the 

Airbus design use SKF by-wire systems 

for cockpit flight control. SKF is also 

a leader in automotive drive-by-wire, 

having jointly developed the revolutionary 

Filo and Novanta concept cars which 

employ SKF mechatronics for steering 

and braking. Further by-wire development 

has led SKF to produce an allelectric 

forklift truck which uses mechatronics 

rather than hydraulics for all 

controls. 

Planning for sustainable growth 

By their very nature, bearings make a positive 

contribution to the natural environment. 

Reduced friction enables machinery to 

operate more efficiently, consume less 

power and require less lubrication. SKF is 

continually raising the performance bar, 

enabling new generations of high-efficiency 

products and equipment. With an eye to 

the future, SKF’s global policies and manufacturing 

techniques are planned and 

implemented to help protect and preserve 

the earth’s limited natural resources. We 

remain committed to sustainable, environmentally 

responsible growth. 

Maintaining a 320 km/h R&D lab 

In addition to SKF’s renowned research 

and development facilities in Europe and 

the United States, Formula One car racing 

provides a unique environment for SKF to 

push the limits of bearing technology. For 

over 50 years, SKF products, engineering 

and knowledge have helped make 

Scuderia Ferrari a formidable force in F1 

racing. (The average racing Ferrari utilizes 

more than 150 SKF components.) Lessons 

learned here are applied to the products 

we provide to automakers and the aftermarket 

worldwide. 


135


R 

® SKF is a registered trademark of the 

SKF Group. 

© Copyright SKF 2004 

The contents of this publication are the 

copyright of the publisher and may not 

be reproduced (even extracts) unless 

permission is granted. Every care has 

been taken to ensure the accuracy of 

the information contained in this publication 

but no liability can be accepted 

for any loss or damage whether direct, 

indirect or consequential arising out of 

the use of the information contained 

herein. 

Publication 4407/II E · April 2004 

Printed in Sweden on environmentally 

friendly, chlorine-free paper (Tom&Otto 

Silk) by SG Tryck AB.

SKF spherical plain bearings and rod ends

Create successful ePaper yourself

Delete template?

Save as template?