Rolling Bearing Mounting-Conical Bore Bearing Mounting

Conical bore bearing can be mounted on conical journal, and can also be mounted on the cylindrical journal while using adapter sleeve and withdrawal sleeve as agent. No matter what situation it is, magnitude of interference of conical bore inner race can be measured according to bearing windage decrease. Radial windage decrease is difference between radial windage before mounting and after mounting. Original radial windage of bearing should be predicted before mounting, windage should be frequently measured in mounting process until the windage reaches radial windage decrease corresponding to ideal magnitude of interference. Radial windage decrease measuring can be replaced by feed amount measuring of bearing on conical journal. For standard taper of 1:12, radial windage decrease is equivalent to 1/15 of axial feeding amount or so. For solid shaft, only 75£¥¡«85£¥ of magnitude of interference of matching surfaces play a part of expanding the inner race.

Radial windage decrease of large-sized spherical rolling bearing and cylindrical rolling bearing is usually measured by proof stick. Notice that radial windage at the two rows of rollers of spherical rolling bearing should be measured the two end faces. Only when the windage values at the two rows of rollers are the same can alignment of inner race and outer race be guaranteed.

Small-sized conical bore bearing can not be measured by proof stick because its radial windage is too small, but its lifting capacity can be measured by using clock gauge to contact shaft or bearing support when feeding. Pay attention to radial windage change here, and elastic deformation of rolling element and raceway is neglected. The forces pushing bearing or bearing support are approximately equivalent to their weight.

When mounting withdrawal sleeve on large-sized bearing, method shown in picture 9-11 can be adopted. Labor can be greatly saved, and the method is applicable for occasion where position is limited and big hook spanner can not be used in particular. The detailed operations are: put the quenched gasket S on the withdrawal sleeve end, slightly wind the nut M, then equably wind the quenched bolt K evenly distributed around the circle until required windage decrease is obtained. Because the withdrawal sleeve can self-locked by friction of its conical surface, it will not get loose even when holding apparatus is taken out. Therefore, operators can be relieved to take compression nut M out, use retaining nut to replace it, and compress the stripped sleeve.

When mounting, smear a thin layer of lubricating oil on the matching surface of the withdrawal surface to reduce friction and facilitate mounting. Notice that the oil can not be too thick, otherwise the withdrawal sleeve will lose self-lock capacity. When taking out the compression bolt and nut and mounting retaining nut, withdrawal sleeve will get loose and deviate set-up position, so faulty mounting can be caused.

Besides, lubricant will overflow or be extruded form fit aperture gradually in working process. As a result, original interference fit of bearing will get loose.

When dismounting the mounted bearing and mounting it on journal again, because the original fit has got loose after the bearing system worked a long period, the nuts can not be screwed to the original position as it is. The cause is that the screws become loose gradually, the matching surface is pressed and certain permanent deformation is generated, and there is definite wearing because of friction. Under this circumstance, the radial windage decrease, the axial feeding amount and expansion figure should be measured again.

If method of hydraulic installation is applied on large-sized bearing, it is swift and saves labor in mounting, and it is convenient in dismounting.

For all the standard withdrawal sleeve and threaded shaft end, bearings can be mounted on conical journal by piston type hydraulic nut, or press withdrawal sleeve in the preset position of the cylindrical journal. The constitution and working principle of piston type hydraulic nut are: press pressure oil into oil cylinder (nut) with the benefit of manual oil pressure pump and through high-pressure hose. Oil cylinder is fixed on threaded shaft end by its female screw, overhang end of the piston thrusts end face of bearing inner race, pressure oil drives piston to push bearing and make it go forward along conical journal. Feeding amount of the bearing can be approximately estimated according to pressure indicated by oil pressure gauge in pipeline.

For experienced bearing mounting personnel, run in bearing by hand to perceive its operating flexibility, and magnitude of interference of bearing can be controlled without measurement by instrument. This is especially true for small-sized conical bore bearing mounting. But it should be implemented after strict test, and there should not be negligence by any chance. Conical bore bearing can be heated and mounted.