Checking friction torque of tapered roller bearings

AR35.30-B-0470-04C

Checking friction torque of tapered roller bearings

Rear axle

741.93 in model 693

Rear axle

741.95 in model 958.1

Rear axle

743 in model 688.277

Rear axle

743.25 in model 368, 382

Rear axle

743.498 in model 688.272/276

Rear axle

746.8/9 in model 382.123/171/175/176/177/184/185/186/188/189, 634.001

Rear axle

746.973 in model 634.011/061

Rear axle

746.974 in model 634.011/061/081

Values that evidence the difference, friction moment

Number

Designation

Axles 743.0/1/2, 743.3, 746.890/891/980/982/983

Rear axle 741.9, 742.8, 745.5/9, 746.5/8/9

BE35.31-B-1001-02C

Pinion bearings friction torque

Nm

1,4 ... 4,2

1,4 ... 6,0

Values that evidence the difference, friction moment

Number

Designation

Axles 743.0/1/2, 743.3, 746.890/891/980/982/983

Rear axle 741.9, 742.8, 745.5/9, 746.5/8/9

BE35.31-B-1002-02C

Thickness of split washers of the pinion bearings - 0.02 mm increments

minimum

mm

6,66

6,60

Maximum

mm

7,08

7,40

1

Select a new split washer. . 

 To determine the correct thickness of the split washer, insert two flat washers of the same thickness between the tapered roller bearings.
Both washers should fit tightly, but without too much pressure.
Pinion bearings should be slightly oiled to facilitate measurement.

 The adjusting split washers are purchased in increments of 0.02 mm and have a deeper diametrical groove to facilitate their separation.

2

Split the selected split washer.

 Remove the burrs of the ends.

3

Place the two halves of the split washer (1) between the tapered roller bearings and check their free rotation.

(Measurement with control device)

(Measurement with torque wrench)

4.1

(Measurement with control device)
Secure the outer races of the bearings using the clamp of the control device (1). 

 Screw the control device (2) firmly on the coupling flange and determine the friction moment with the sliding weight on the rocking arm.
The moment will correspond to a preload of 0.00 to 0.02 mm (without considering the initial impulse).

4.2

(Measurement with torque wrench)
For measuring using a torque wrench, attach the clamp of the control device (1) and fasten the torque wrench (2) to the collar using an appropriate socket. 

5

Measure the frictional torque. . 

 Frictional torque HIGHER than the prescribed value = apply SMALLER split washer
Frictional torque LOWER than the prescribed value = apply BIGGER split washer
For new tapered roller bearings, leave the friction moment near the top limit of the tolerance band.