PROCESS VARIABLES EFFECT ON THE CASTING PRODUCED BY SHELL MOULDING PROCESS

Abstract

The shell moulding process is a precision casting process used to produce complex castings. This process is revolutionary, offers cost saving and product quality improvement. Many advantages, such as good dimensional accuracy and better surface finish can also be achieved by this process. Now-a-days quality concept is changing towards the design phase of the product and process i.e. controlling the quality at design stage instead of controlling at the manufacturing state. This is the underlying idea of off line quality control. One of the most comprehensive and effective system of quality control is Taguchi's Technique, which aims at achieving consistent quality of the product. The objective of the present work is to optimize the process variables like pattern temperature, contact time, curing time and pouring temperature for the dimensional accuracy, mechanical properties and surface roughness of the castings. Taguchi's parameter design approach has been used to ascertain the optimal parameters. The Al-7%Si alloy is poured to the shell moulds for preparing castings. The experimental work has been carried out by using L9(43)OA. The main effects of process parameters on the quality characteristics have been plotted. Predicted optimal mean and ranges of the quality characteristics have also been evaluated.