1、2950 英文单词， 14500 英文字符 ，中文 3700 字 文献出处： Das C R, Albert S K, Bhaduri A K, et al. Failure analysis of a pinionJ. Engineering Failure Analysis, 2005, 12(2): 287-298. Failure analysis of a pinion C.R. Das, S.K. Albert, A.K. Bhaduri, S.K. Ray Abstract A pinion, which was a part of an air-motor driving a
2、diesel generator (DG) of a power plants emergency power- supply system, was found to have failed into three parts during a routine check-up of the DG. This pinion, attached to the air-motor shaft is active only for a short duration during the start up, when the motion of the air-motor shaft is trans
3、ferred to the ring gear attached to the DG which in turn starts the DG. Once the DG has started, the pinion disengages from the ring gear and the air-motor stops. The pinion that failed had been in operation for a long time and experienced several start-up operations before failure. A systematic fai
4、lure analysis was carried out to nd out the reasons for this unexpected fracture of the pinion during operation. The results indicate that the fracture was caused by fatigue with a fatigue crack initiating from the llet of one of the pinion teeth. Due to misalignment that was present, the pinion did
5、 not mesh properly with the ring gear during the start-up operation and this led to a high stress concentration at the root of the pinion. The misalignment also led to severe wear and excessive heat generation at the mating surface. Misalignment, improper heat treatment, non-uniform distribution of
6、sulphide inclusions and sharp corners would have all contributed to the failure of the pinion. Keywords: Gear failures; Misalignment; Inclusions; Fatigue crack; Heat treatment 1. Introduction Continuous operation of power plants necessitates the use of diesel generators (DGs) for providing emergency power supply during unexpected power failures. One of the common methods used for the start-up of these DGs is to use an air-motor that is driven by air released from an air compressor in the e
