Remanufacturing process optimization method for crankshaft based on failure modes
                                                                CUI Xiang ，ZHANG Xiufen，XUE Junfang
                  (The College of Mechanical Engineer, Inner Mongolia University of Technology, Hohhot 010051,China)

Abstract: Aiming at the problem that the process routes are complicated and diversified in crankshaft remanufacturing, the crankshaft working conditions, material selection, failure causes and damage degree were studied and a remanufacturing process optimization method for crankshaft based on failure modes was presented. The main causes of crankshaft failure were analyzed by fault tree analysis method and expressed by tree diagram. Futhermore, the key factors affecting remanufacturing process were extracted as failure characteristics. The quantitative criteria of failure characteristics for crankshaft were proposed based on engineering experience in practical work, and the quantified results were taken as the main conditions for selecting remanufacturing process. The unreasonable process routes were removed by remanufacturing process standards and the result was expressed as AND/OR diagrams. Remanufacturing cost function including economic and time costs was established. And the evaluation results were processed by dimensionless method. The simplified routes were analyzed and compared, the lowest cost route was selected as the optimal route of remanufacturing process. The point of wear, crack and deformation failure of DB7020 Passat automobile crankshaft was analyzed. Remanufacturing process routes were obtained by applying remanufacturing process optimization method, and the optimal route was obtained by remanufacturing cost function. The results indicate that the problem of process complexity caused by different failure forms and degrees of used crankshaft can be solved by remanufacturing process optimization method.And the rationality of process selection and remanufacturing efficiency can be improved.

Key words: remanufacturing; crankshaft; failure modes; process optimization; material