The Small Sample Failure Distribution Model of Diesel Engine Component Parts Using the FMECA Approach

Abstract

This paper aims to provide a way to deal with the small sample related to failure data for reliability based on FMECA approach. In order to help optimize the reliability of products using a systematic method, a theoretical approach is applied, starting from the traditional theory of failure mode effects analysis (FMEA). Then a novel small sample failure distribution parameter estimation which employs the least square method and the maximum likelihood method is proposed, and their estimation values under the same situation are compared. The least square estimation is validated to be more efficient than the maximum likelihood parameter estimation and thus is more suitable for the model building. Based on the reliability data from the database of our research group, the distribution model of the critical diesel engine component is developed. Finally, a distribution is implemented, which can obtain the failure probability density function curve and the failure rate curve.