1.Measurement and adjustment of radial clearance

To ensure that the radial clearance reserved for the radial thermal expansion of the inner ring, roller, and shaft during operation is not too large or too small, and to prevent changes in installation clearance in the later stage, the following measurements should be taken. When the specified installation clearance cannot be reached, gradually adjust it to the specified installation clearance according to the normal installation method.

A.The bearing installed using the A heating method requires the shaft to be isothermal with the bearing and the installation clearance to be measured again.

B.Before installing the lock washer, measure the installation clearance again.

C.When replacing the oil pressure nut with a locking nut, measure the installation clearance again.

D.After unloading the oil pressure of the injection pump, measure the installation clearance again.

2.Axial positioning and adjustment of self-aligning roller bearings

(1) Pressing method for inner ring of self-aligning roller bearing

Use locking nuts, end caps, end caps, or oil pressure nuts to directly press the bearing onto the conical shaft A;

Use locking nuts or oil pressure nuts to directly press the bearing onto the B set sleeve;

Use a locking nut or oil pressure nut on the shaft to press the C disassembly sleeve to install the bearing.

⑵ Setting and implementation of axial clearance

                                                             Unit: (10-6) m/℃

According to the coefficient of thermal expansion and working temperature of the materials used for the shaft and the bearing seat (housing), calculate the axial expansion amount of their temperature rise respectively. The difference between the two expansion amounts is the axial displacement amount of the bearing inner ring and outer ring caused by the difference in the working temperature difference between the shaft and the bearing seat and the coefficient of thermal expansion of the materials. Due to the enormous thermal expansion force of metal materials, which is irresistible, if the axial preload generated by the installation of self-aligning roller bearings and the axial force generated by the thermal expansion of the shaft are superimposed, it will inevitably cause the bearings to withstand a huge axial force and be damaged. Even thrust bearings cannot withstand this superimposed axial force.

To avoid damage to the self-aligning roller bearing due to significant axial force, it is necessary to leave the axial clearance required for shaft thermal expansion between the end cover of the movable end bearing and the end face of the bearing outer ring during bearing installation. At the same time, it is necessary to ensure that the outer diameter of the movable end bearing matches the seat hole with a small clearance to ensure that the movable end bearing will move axially (axial creep) during shaft thermal expansion. When installing self-aligning roller bearings with fixed ends at both ends of a shaft, axial clearance should be left between the bearing end caps and the bearing outer ring end faces at both ends of the shaft, and the outer diameter and seat holes of the bearings at both ends should be fitted with small clearances.

After bearing installation, the radial installation clearance should not be less than the remaining clearance; The axial installation clearance should not be less than the maximum thermal expansion of the shaft, and ensure that the rotating parts on the shaft do not interfere with non rotating parts during axial displacement.

In the legend, when a set of self-aligning roller bearings is combined with two sets of tapered roller bearings in a back to back configuration, it is recommended that the radial clearance of the tapered roller bearings in a back to back configuration is less than or equal to the installation clearance of the self-aligning roller bearings. The outer diameter of the self-aligning roller bearing should match the seat hole with a small clearance, and an axial clearance should be left between the bearing end cover and the outer ring end face of the self-aligning roller bearing.