This paper reports the result of an experiment using statistical research methodology to evaluate previous findings, identify new effects and focus on potential future research efforts to improve the control of casting surface roughness.
The objective of developing a functional equation to predict casting surface roughness was achieved. A reliable and valid methodology for obtaining operational "surface imprints" of casting surface roughness was developed.
Gray iron castings within a weight range of 1 to 7000 pounds were studied. The population of 142 surface roughness measurements came from five foundries in the northeast regions of Pennsylvania, Vermont, Maine, and Massachusetts. The dependent roughness variable had an average surface roughness of 444 micro inches arithmetical average (AA) with a standard deviation of 254 micro inches.
Main effect variables of sand fineness and mold wash were found to have significance. The nonlinear importance of sand fineness and the interaction of metal pressure and sand fineness were clarified.
Questions were raised on the absence of significance of effects of mold hardness and casting weight on surface finish. The feasibility of applied research in the foundry operating environment was determined to be a practical research environmental option.
Ekey, D.C. "Inferential Operations Research on Surface Finish of Castings." E.C.R.S.B. 86. Robins School of Business White Paper Series. University of Richmond, Richmond, Virginia.