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VALUE ADDED SIMULATIONS OF DIE CASTING PROCESSES
integrity die casting supplier to optimize the process for the com- ponent. For each individual simulation, a goal must be defined as
well as a metric to measure success. Most product timelines clearly define the date a design must be
completed with fully dimensioned drawings and specification. When preparing a timeline, it is important to specify an earlier
date at which a design is to be ready for use in computer simu- lations. Multiple iterations of any given simulation are often nec-
essary when seeking an optimized design. Also included should be a time before design release to repeat simulations.
9.3.3 Coupling Product and Process Simulations
Often process simulations are conducted by suppliers after designs have been completed and formally sourced. In such cases, opti-
mization of the manufacturing process is limited to process parameters. The opportunity to modify the design to improve man-
ufacturability is lost.
Sharing design data with suppliers prior to design release with the purpose of conducting process simulation can result in signif-
icant improvements in manufacturability and reductions in cost during production. Formal drawings with complete dimensions are
not required to complete such activities. Raw three-dimensional computer-aided design CAD data are all that is required. In
many cases, results from the process simulation can be used to predict functional properties of the product as well.
9.4 COMMITMENT
When choosing to conduct simulations, an organization must be committed in order to be effective. Capable individuals must be
selected and dedicated to the task of computer modeling. Simu- lations must be conducted prior to the completion and release of
a design. An organization must plan for success.
9.5 A CASE FOR SHARING SIMULATION DATA
ACROSS ORGANIZATIONS
During the development of a structural component for an auto- motive chassis, a supplier and original equipment manufacturer
REFERENCES
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OEM worked concurrently to engineer both the product and the process. Simulations were conducted by the OEM to analyze the
stresses within the component during operation. The supplier used computer modeling to develop a gate and runner system. The re-
sults of the simulations were not exchanged due to ‘‘proprietary’’ reasons. Conclusions drawn from the results, however, were
shared freely, resulting in minor changes to the design to improve function and manufacturability. At release, the partners believed
both the product and process had been optimized.
Prototypes were fabricated from production, such as tooling, for product verification tests. The initial prototypes failed. Al-
though simulations were conducted concurrently, the simulation results were never examined side by side. Comparison of the sim-
ulation results showed that two major metal fronts in the die con- verged at the point in the structure that bore the highest stresses
during operation. The process tooling was redesigned such that the two metal fronts converged at a low stress point within the
structure. Had the results of the product and process simulation been compared earlier, redesign of the process would have been
avoided.
REFERENCES
1. Robust Design Using Taguchi Methods Workshop Manual, American Supplier Institute, Livonia, MI, 1998.
2. Solutions, American Supplier Institute, Livonia, MI, 1999. 3. Clausing, D., Total Quality Development, ASME Press, New York, 1994.
4. Vinarcik, E., ‘‘Minimizing Cost Through Part Integration,’’ Engineered Cast- ing Solutions,
Winter 1999, p. 56.
