Application of DFMEA to Improve Producibility of Legacy Products

摘要

Design Failure Modes and Effects Analysis (DFMEA) is usually conducted during the design phase of new products to identify possible ways in which a part or system could fail to meet its requirements. Analysis for existing products is typically limited to design or process changes, or new applications. Rolls-Royce has developed and implemented a practical application of DFMEA to existing products (the terms product and part are used interchangeably throughout this paper) with the intent of improving producibility, decreasing the risk of disruption in the manufacturing process, decreasing the cost of non-quality (CoNQ) associated with internal and external failures, and improving customer satisfaction. Since parts are already in production, the DFMEA process is able to assess failure modes, effects, severity rating and causes based on both actual data and engineering judgment of potential modes, effects, etc. Key to this step is the involvement of a cross-functional team familiar with the actual manufacturing and service history of the parts. DFMEA output becomes the basis for follow-on activities to identify improvements including changes to part definitions, manufacturing processes, inspection criteria, control plans, Measurement System Analyses (MSA), and capability studies. In its first full year of use, this technique was applied to 33 parts.