【作者】

Mengqi Wang,

【摘要】

该论文已在芬兰赫尔辛基举行的第28届CIMAC大会上发表。论文的版权归CIMAC所有。After a long-term use of a power machinery, the rubber portion of the elastic coupling might change in someway and deviate from the parameters or characteristics designed. Due to this deviation, the inherent parameters of the power set will change, which might cause the unstable adjust of the speed control system and the occurrence of malfunctions. Thus, it is extremely essential estimating the actual parameters of a elastic coupling stiffness after a period of running. In order to solve the severe wear of the timing gears of a certain type diesel engine set, the torsional vibration calculation of the engine shafting has been done, which shows that the stiffness of the coupling has a maximum effect to the whole shaft by the first vibration mode. Hence, the coupling is highly concerned,in the meantime,a torsional vibration test on site has been done. The natural frequencies of the test were compared with the theoretical calculation using the parameters designed, which illustrates an error of 9% at most. The torsional-vibration equivalent simulation model was established to calculate the high-elastic coupling stiffness which is 0.54MNm/rad based on the test results. With this stiffness, the error of the natural frequencies has been decreased to 1.1%. Since the original stiffness of the coupling is 0.36MNm/rad, the actual coupling stiffness is no longer meet the designed one. Obvious crack damages can been observed from the coupling unloaded. These results indicates that the abrasion of the gears was might caused by the change of the power set inherent figures through the deviation stiffness of the coupling, which leads to the instability of the speed control system. After the replacement of the new coupling, a test has been done on board again. The stiffness of the new coupling has been calculated with the same method, which is 0.42MNm/rad. This result is basically consistent to the stiffness 0.44MNm/rad obtained from a dynamic torsional performance test station, which verified the effectiveness of this method. This paper presents a reverse estimation method calculating the real-time dynamic stiffness of the couplings by shafting torsional vibration test of the power unit on site and establishing an accurate torsional-vibration simulation model of a power shaft which is corrected by the test results. Using this method, it can not only be learned of the realtime dynamic stiffness of the couplings, but also has been used to discover crack damages of a high-elastic coupling on a diesel set, which prevented the occurrence of an unnecessary accident. In this way, this estimation methodprovides a new idea of diagnosis and can be applied to fault diagnosis of a power machinery.

【会议名称】

第28届CIMAC会议

【会议地点】

芬兰 赫尔辛基

【下载次数】

2

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