Bearing reparation

If bearings are to be used again after removal, the dismounting forces should by no means load roller units and raceways. In the case of non-separable bearings, the ring with clearance fit is taken off first. Ring with interference fit can be dismounted in many ways.

Dismounting bearings with cylindrical bore
Smaller bearings can be dismounted with light hammer strokes, through a rubber-made inserted piece, on the ring face. It is better to work using tools for dismounting process (a) (when constructing a bedding foresee the necessary grooves and other), or screws (b) that are screwed into already made holes for hydraulics implementation.
When removing rings of separable bearings, heated inner rings can be applied, whether electrical induction heaters (c) for smaller rings, or slotted rings (d) for bigger diameters, which is separately heated on a hot plate, heating furnace or on an open flame where temperature is around 200°C. Because of a better heat transfer, the inner ring should be lubricated with anti-oxidation oil.

Diagram 12 Estimation of the actual operating viscosity

Diagram 12 Estimation of the actual operating viscosity

Dismounting bearings with tapered bore
In the case of smaller bearings, they can be removed by loosening the sleeve nut a few turns first and then using a hammer and tubular drift or special segmental drift (29.a). When dismounting bearings on withdrawal sleeves, the axsial locking device (shaft nut, end cover etc.) is removed. The withdrawal nut is then screwed on to the threaded section of the sleeve and tightened until the sleeve comes free. If the threaded section of the sleeve protrudes beyond the shaft end or shaft shoulder, a support ring having the greatest possible wall thickness should be inserted in the sleeve bore to prevent distortion and damage to the thread when the nut is tightened (b).
Larger bearings with tapered bore should be dismounted using hydraulics and connections provided during the construction of bearing arrangement.

Fig. 26 Dismounting bearings with tapered bore

Fig. 26 Dismounting bearings with tapered bore