Investigation of a Best Maintenance Strategy Toward Extending the Service Life of the Air Starting Motor

• Main Authors: Wen-Hsiu Chen, 陳文秀
• Other Authors: Chen-Hua Wang
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/52612848293588244929

碩士 === 國立高雄第一科技大學 === 環境與安全衛生工程所 === 94 === ABSTRACT The study was originated from a problematic air starting motor of a specific type of refueling trucks. During the 10 years of so of service life, failures of the air starting motor are the major reason behind loss of service hours. We started by gathering the motor related failure data from the same batch of trucks. Next, failure modes, effects, and criticality analysis (FMEA) was performed on the starting system of the truck, followed by fault tree analysis (FTA) in order to obtain a clearer picture of the possible failure scenarios. The scale factor of 1790 and shape factor of 1.8 from the Weibull analysis reveals the average life of the starting motor is around 1591 days, which is not satisfactory for service requirements. Based on such a goal to extend the mean time between failures (MTTF), the focus turns to planning of an optimal maintenance. Numerous analyses have been performed. In the end, the most efficient maintenance intervals have been determined. As for the spare parts of the air starting motor is suggested via the Poisson distribution method at 80% availability level. Efforts to extend MTTF cannot be based on reliability techniques alone. Other approaches such as training of maintenance staff and disciplinary requirements to follow operating procedures must be enhanced simultaneously. After all, the original designated purpose of the air starting motor is not for frequent start-ups and shut-downs. Everything must be carefully and precisely executed in order to extend the maintenance interval as well as the MTTF.