A Study On Diesel Engines' Relability And FMECA For Engineering Machinery

With the rapid development of our economy, engineering machinery is widely used. Most engineering machinery is powered by diesel engines. The reliability of diesel engines is not only related to normal operation of the engineering machinery, but also related to maintenance costs and downtime losses.How to improve the reliability of diesel engines is important.The research object in this paper was the reliability of diesel engines in using process. Based on the investigations to the field data of maintenance in a heavy vehicle 4S shop, the reliability of the diesel engines was researched by studying on the reliability indexes such as the distribution, reliability of quantitative indicators and failure life. The influence of using factors to the reliability was analyzed. According to the fault data, in order to improve the reliability, Failure Mode, Effects and Criticality Analysis (FMECA) method was used.The improvement suggestions were proposed.The research investigated the fault data of diesel engines. With the aid of MATLAB, the distribution model was determined through judging the distribution model of the fault data, estimating the distribution parameters by using maximum likelihood method, and inspecting whether the fault data was meeting the hypothesis distribution by using K-S method.The reliability indexes of diesel engines was obtained. Considering different using conditions of diesel engines, suggestions to improve the reliability were proposed. Failure Mode and Effects Analysis (FMEA) and Criticality Analysis (CA) were applied to all subsystems of diesel engine by FMECA method. The failure mode, failure reason, failure consequences and the compensatory measures are analyzed by using FMEA. Based on FMEA, Criticality Analysis was accomplished with the fault data.The latent weakness of the diesel engines was discovered. Improvement suggestions of the reliability in service stage of diesel engines were put forword.