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With the developments is automobile and machine, rolling bearings are required to work under harder conditions of high speed and heavy load than before. Hard conditions may lead to a greater likelihood of happening of kinds of bearing problems. One example is the problem of ring creep, which may result in unusual noise and cause bearing wear. Ring creep is referred to a phenomenon that a bearing ring rotates slightly relatively to the housing or the shaft during the operation.

Because of the continuous quests for high performance and compact structure of automobile and machine in recent years, rolling bearings are required to work under harder conditions of high speed and heavy load than before. The applications of hard condition may lead to a greater likelihood of happening of bearing malfunctions such as flaking, wear, creep, fracture etc. In this paper, the phenomenon called outer ring creep occurring in bearings subject to non-rotating load is discussed. Outer ring creep is referred to that bearing outer ring rotates relatively to the housing in certain applications. Outer ring creep may result in such problems as unusual noise and vibration and may cause wear of housing and outer ring. If abrasive particles caused by wear of the ring and housing enter the raceway, the bearing may be damaged and destroyed. Conventionally, the problem of outer ring creep was considered to be a result of rotating bearing load. However, even if the direction of radial load remained relatively unchanged, outer ring creep is observed in many cases. The generation mechanism of this kind of outer ring creep has not yet been made clear till now. With FEM simulation and test verification, we analyzed the phenomenon of outer ring creep under non-rotating load. We concluded that outer ring creep under non-rotating load is a result of localized strain and rippling deformation caused by rolling elements. In this paper, only outer ring creep is discussed below, but the similar result can be obtained for inner ring creep.

Bearings used in electrical engine-driven accessories, such as alternators and air conditioner (A/C) compressor pulleys, generate flaking related to non-metallic inclusions of unusual microstructure (white structure flaking), which occurs at one-tenth to one-twentieth of the calculated bearing life. In this paper, we will describe our investigation of the mechanism of white structure flaking, and report on how we achieved extended service life of engine-driven accessory bearings by implementing an evaluation of white structure flaking based on the discovered mechanism. We verified that the tribochemical reaction of grease, and statistic electricity generated by friction between the drive belt and pulley were the main culprits of white structure flaking. White structure flaking was further augmented by hydrogen invading the bearing steel, which further impaired bearing life.