Robust, Producible Design Process Evolution

ABSTRACT

Until about 10 years ago, design engineering and manufacturing at our company were separate organizations. Design engineers produced part designs for an integrated engine system and expected manufacturing to make and assemble the parts. Tolerance decisions were influenced by the arguing ability of each discipline along with historic precedent. Most form-fit-function characteristics were about 95% producible or two-sigma designs. Nonconformance control by a Material Review Board (MRB) was used by design engineering to monitor manufacturing quality. Although this process demonstrated the ability to produce excellent engines, it depended on inspecting in quality, multiple rework loops and resulting high cost.

This article will discuss the evolving process used to design engines that are producible and error proofed. Discussion will include the organizational structure supporting the needed culture change, the six-sigma impact of common terminology and data driven decisions, the structured approach using manufacturing process capability data to facilitate producibility, use of assembly defect and customer escape data to drive error-proofing early during the design process, and the focus on standardized notes and automated characteristic accountability for error prevention. Discussion will include examples demonstrating the significant improvements in quality and producibility accomplished by the new process.

KEYWORDS:

• error proofing
• manufacturing producibility
• organizational change
• quality
• robust design