The answer to this month's trouble shooter is provided by Schaeffler (UK) Ltd - Q Do you really need to purchase a replacement rolling bearing, or can the existing one be reconditioned?
Published: 09 October, 2015
Many rolling bearings are replaced as part of routine maintenance activities, particularly on critical high value plant and machinery. However, in many cases, the bearings can be restored to a completely acceptable, functionally reliable condition using appropriate cleaning and rework techniques. This is particularly true if the bearings are large, where reconditioning or rework can often save valuable time and money.
Reconditioning or maintenance costs of a large rolling bearing typically amount to between 15% and 70% of the cost of a new bearing, depending on the extent of the reconditioning work involved. Average costs are around 50% of new purchases.
Bearing reconditioning typically begins with an initial, in-depth damage diagnosis of the bearings, in order to determine whether reconditioning is appropriate and economically viable. For the repair itself, all the negative effects of wear and plastic deformation on the working surfaces can be removed. If certain components cannot be repaired, these can be completely replaced. Reconditioning typically comprises appropriate cleaning and dismounting of the bearing and the preparation of examination reports. What follows could range from simple polishing work, through grinding and replacement of individual components, to the substitution of a complete inner or outer ring.
Reconditioning can be applied to all types of rolling bearings, including back-up rollers, radial spherical roller bearings (ODs >500mm), cylindrical roller and tapered roller bearings.
Once the appropriate processing has been carried out, the reconditioned rolling bearings should provide the same performance as new bearings.