Quality and computer modeling for the next decade.

The engineering panel on advanced quality planning (AQP) (90-104) targeted three potential areas for improving quality in the foundry. J. Cline, Globe Metallurgical, Inc, discussed the necessary tools to monitor a process control plan in production. Quality personnel need to identify critical process variables and set operational limits within specifications. B. Grigg, Roberts Div/Grede Foundries, covered an actual case history utilizing the Failure Mode Effect Analysis (FMEA) technique. They found a need to enforce additional process controls to detect causes for failure before castings leave the foundry.

D. Lively, Citizens Gas & Coke, discussed the need to assure the quality of the foundry coke they produce. This was implemented using Quality Function Deployment (QFD). This system is similar to FMEA's in that it prioritizes details based on the customer needs. The results of QFD were a complete documentation of their cokemaking process.

Other approaches to quality were addressed in a second panel (90-194). J. Coomer, Univ of Wisconsin/Stout discussed production improvements through team involvement. Three types of teams can be developed: quality circles, task forces, natural work teams and self-managed teams. This method can be utilized for area requiring improvement, safety, quality, etc.

R. Lewis, The Ohio State Univ, discussed the application of mixed integers math techniques for scheduling (90-154). The model included seven small, five medium and four large case studies, using 20 different molds and 67 cores. Their model ran on a mainframe system but is expected to run on individual workstations.

Quality systems and their impact on the foundry were covered by D. Scrimshire, TEC Ltd (90-94), who discussed where quality improvements offering significant financial gains can be made in return for very modest investments. American foundries will be well positioned to meet the demands of an European marketplace when they attain BS 5750 status.

There are different problem areas that need to be addressed when smaller foundries try to control quality, stressed T. Law, Dewtec Systems, Ltd (90-87). The advent of ISO 9000 and BS 5750 quality standards and databases have helped to integrate quality in the foundry. Software is now available to help with production and quality functions in the foundry.

Accurate elemental analysis as an alternate area for improving quality (90-25) was addressed by W.C. Batie, A.E. Bernhard and E.J. Edin, Analyte Corp. The use of spectrometers provides a highly accurate analysis of complex metal alloys..

Coremaking

A panel discussion on "High Technology Coremaking" (90-197) was opened by W.E. Schultze, Caterpillar, Inc, who discussed the process variables that must be controlled in order to produce acceptable castings. Some areas are sand quality, temperature, moisture and cleanliness.

Panelist R.E. Fiser, Central Foundry Div/General Motors Corp, stressed the importance of utilizing high technology coremaking techniques to yield excellent quality castings. G. Blachins, Morris Bean & Co, discussed the effects of CAD/CAM on the coremaking process. R. Smith, Sand Mold Systems, Inc, discussed essential desi n features needed in selecting core making equipment and F. Degner, Brillion Iron Works, covered the finishing and handling systems used in coremaking processes.

Computer Applications

In another engineering panel, "Computer Applications for Foundry Maintenance" (90-52) was covered by R. Norman, Grinnell Corp, T.J. Brinker, Appleton Electric and D.C. Schmidt, AFS. Norman stressed training in statistical control and total productive maintenance concepts for employees. Brinker addressed retrofitting of existing equipment with PLCs for controlling maintenance and Schmidt summarized the key points involved in selection of a maintenance software system.

The advantages of maintenance systems, according to Schmidt are reduced equipment failure, inventory, etc. Predictive maintenance can be less costly than waiting until a failure occurs. He also touched on the numerous software packages available that are PC compatible and reasonably priced.

Growing interest in computer modeling techniques for the foundry has become increasingly evident. This topic was addressed in four presentations. A study of the effectiveness of chill materials (90-58) was conducted using a computer model by H. Huang and J.T. Berry, Univ of Alabama, and A. Lodhia, AT&T Labs. Varying chill materials were found to have different degrees of effectiveness, depending on thermal properties and size.

Another model was developed to investigate' the effects of casting parameters on the formation of microporosity due to interdendritic flow (90-164) by I.J. Chiou and H. L. Tsai, Univ of Missouri/Rolia. J.H. Chen and H.L. Tsai, also with the Univ Missouri/ Rolla, discussed a multi-dimensional solidification model that was based on control volume finite differences (90132). The effect of latent heat release on two alloys also was studied by the same authors (90-133). Care must be exercised when selecting the actual latent heat release for modeling, they said, in order to correctly predict the casting temperature distribution.