EFFECT OF ROLLING BEARING REFURBISHMENT AND RESTORATION ON BEARING LIFE AND RELIABILITY~©

摘要

For nearly four decades it has been a practice in commercial and military aircraft application that rolling-element bearingsrnremoved at maintenance or overhaul be reworked and returned to service. The work presented extends previously reportedrnbearing life analysis to consider the depth (Z_(45)) to maximum shear stress (τ_(45)) on stressed volume removal and the effect ofrnreplacing the rolling elements with a new set. A simple algebraic relationship was established to determine the L10 life ofrnbearing races subject to bearing rework. Depending on the extent of rework and based upon theoretical analysis,rnrepresentative life factors (LF) for bearings subject to rework ranged from 0.87 to 0.99 the lives of new bearings. Based onrnbearing endurance data, 92 percent of the bearing sets that would be subject to rework would result in L_(10) lives equalingrnand/or exceeding that predicted for new bearings with the remaining 8 percent having the potential to achieve the analyticallyrnpredicted life of new bearings when one of the rings is replaced at rework.. The potential savings from bearing rework variesrnfrom 53 to 82 percent that of new bearings depending on the cost, size and complexity of the bearing.