CONCLUSIONS OF THE CASE STUDY

REFERENCES 123 ease in production using the semi-solid metalworking process var- ies greatly due to their respective geometries. Although the desire may exist to implement a high integrity die casting processes with any product, problems will always be encountered when attempt- ing to manufacture a design that was optimized for another man- ufacturing method. Six general design for manufacturability guidelines were re- viewed in this chapter. The topic of high integrity die casting design, however, extends well beyond the brief discussion pre- sented in this book. Texts are available focusing on this single subject. 6,7 In all cases, designers and product engineers should consult the manufacturing engineers and die makers ultimately responsible with manufacturing a component in production. The vested interest and feedback of these individuals will improve component quality and reduce total costs. REFERENCES 1. Sully, L., ‘‘Die Casting,’’ in Stefanescu, D. editor, Metals Handbook, 9th ed. Vol. 15, Casting, ASM International, Materials Park, OH, 1988, pp. 286–295. 2. Ruden, T., Fundamentals of Die Casting Design, Society of Manufacturing Engineers, Dearborn, MI, 1995, pp. 19–37. 3. Moschini, R., ‘‘Manufacture of Automotive Components by Pressure Die Casting in the Semi-Liquid State,’’ Die Casting World, October 1992, pp. 72–76. 4. Moschini, R., ‘‘Mass Production of Fuel Rails by Pressure Die Casting in the Semi-Liquid State,’’ Metallurgical Science and Technology, Vol. 12, No. 2, 1996, pp. 55–59. 5. Jerichow, U., J. Brevick, and T. Altan, A Review of the Development of Semi- Solid Metal Casting Processes, Report No. ERC NSM-C-95-45, The Ohio State University Engineering Research Center for Net Shape Manufacturing, Columbus, OH, 1995. 6. Product Design for Die Casting, 5th ed., Die Casting Development Council of the North American Die Casting Association, Rosemont, IL, 1998. 7. Jorstad, J., and W. Rasmussen, Aluminum Casting Technologies, 2nd ed., American Foundry Society, Des Plaines, IL, 1993. 125 8 COMPONENT INTEGRATION USING HIGH INTEGRITY DIE CASTING PROCESSES

8.1 INTRODUCTION TO COMPONENT INTEGRATION

Product cost is a function of design. A skilled manufacturer may be able to reduce scrap and optimize a process to achieve near- ideal efficiency, but the cost of a product can never be reduced further without improving the design. Major reductions in product cost can only be attained through discerning design work. During design, the best way to minimize cost is to keep the design simple by first minimizing the number of individual com- ponents and then assuring that the remaining components are easy to manufacture and assemble. Engineers and designers must be aware that every time two parts are integrated into one, at least one operation or process is eliminated during manufacturing. In most cases several operations are eliminated along with the sup- port activities associated with each component, such as inventory control.

8.2 HIDDEN COSTS IN EVERY COMPONENT

Every component has a cost associated with it. Often the cost is quantified by looking at the price of the raw material, but this 126 COMPONENT INTEGRATION USING HIGH INTEGRITY PROCESSES quantification is oversimplified and leaves out much of the true financial burden. From a total-cost standpoint, the life cycle of a component is as follows: Designed Drafted Quoted Sourced to an internal or external supplier Tooled Approved Manufactured Packaged Inventoried Shipped Received Handled Assembled into the final product Although all of these points contribute to the total cost of a com- ponent, the attachment of a price tag to each point is difficult to ascertain. One major automotive company has estimated the ad- ministrative burden to maintain one part at 50,000. This may seem unreasonable, but the estimate includes the time to prepare and detail a drawing, approval of the design, distribution of the detailed print, cataloging the part into a worldwide database, scan- ning the part’s drawing into a global computer site, tracking changes or updates to the drawing, and much more. Once a product is no longer being manufactured, the financial burden continues. One must consider the servicing of products in the field. Service parts must be packaged and warehoused, some- times for years, before they are shipped to customers. From a quality standpoint, every component adds risk. Fewer parts means fewer things can go wrong during manufacturing, and fewer things can go wrong once the product is in the field. Every quality issue or problem carries a financial burden whether it is fixed or not.