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MANUFACTURABILITY OF HIGH INTEGRITY DIE CASTINGS
Figure 7.7 Shrinkage porosity found in the body of a production Z-2 fuel rail.
requirements. To enhance the manufacturability of the Z-2 fuel rail design further, a second improvement would be to taper the
outside of the fuel rail body to follow the taper of the center core. Following the taper of the core would create a uniform wall thick-
ness for the body of the fuel rail.
A third area for further improvement is in the feeding of metal into the mounting legs. The current Z-2 design forces the metal
to turn 90⬚ to its natural flow path. The addition of a large fillet at the interface between the mounting leg and the body of the fuel
rail would assist in metal filling.
7.4 CONCLUSIONS OF THE CASE STUDY
Observations made in this case study reinforce the design for man- ufacturability guidelines for high integrity die casting processes
presented in Section 7.2. The two fuel rail designs reviewed in the case study functionally serve the same purpose. However, the
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.
