Streamlining tool design and manufacturing process for blancing and function test equipment to a propeller hub assembly

Abstract: Rolls-Royce AB in Kristinehamn, Sweden, part of Rolls-Royce Marine, is a leading developer and supplier of water jet and propeller based propulsion equipment. Its low volume production series and wide product variety offered to its customers along with an increasingly competitive market has entailed an increased demand on both delivery time and cost reductions. The on-site manufacturing engineering department is responsible for developing all tools and fixtures, and programming required to maintain the on-site production, assembling and quality testing. As part of the departments streamlining efforts this study aimed on evaluating streamlining possibilities related to the existing tool design used for static balancing and function testing controllable pitch propeller assemblies before packaging and shipping, along with the related tool development and manufacturing processes has been conducted.The process evaluation started from the point when a hub assembly design was finalized until when a manufactured tool was delivered for use in production. Work focused on locating inefficient activities and product properties, with respect to tool cost and lead time, followed by setting up an amendment proposal, implementing it and producing an alternate tool design of which the effects on tool cost and manufacturing lead time would be evaluated. Post evaluating the current state of the process and product a set based front loaded product development methodology known as Modular Function Deployment was chosen to be the applied method. This application resulted in a modular tool design that avoided the determined most inefficient manufacturing operation combination of welding and annealing. Modularity increased manufacturing flexibility, enabling more concurrent manufacturing, to reduce the lead time. The tool design also applied integral properties by identifying the common components and features between tool sizes. This led to reducing manufacturing and material costs. Possible lead time reduction for manufacturing was determined to be 35-45%, 3-4weeks, in comparison with the original tool design due to increased parallel manufacturing and avoiding inefficient manufacturing methods. The estimated cost reduction for combined development and manufacturing was determined to be 105K SEK the initial year followed by 175K SEK the second year assuming the current tool manufacturing rate. The combined effects of reduced cost and lead time would be beneficial to Rolls-Royce AB by contributing to an increase in delivery reliability and competitive prices on the market