APPLICATION OF ISHIKAWA DIAGRAM TO INVESTIGATE SIGNIFICANT FACTORS CAUSING ROUGH SURFACE ON SAND CASTING

This paper discusses the identification, mechanism and causes for the rough surface defect on the sand castings. In foundries raw materials are transformed into finished casting using many intermediate processes like pattern making, moulding, core making, melting and fettling. It is very difficult to control all these processes due to the involvement of lot of people and materials. It is always a challenging task for the foundrymen to produce quality castings with good surface finish consistently. Generally rough surface on casting may occur due to a single cause or a combination of causes. Hence, identification and finding the root causes for rough surface defect are important to prevent its occurrence further. The possible causes for rough surface defect involving the foundry tools and processes are presented as cause and effect diagrams. The main outcome of this paper is to investigate the significant factors causing this defect and to prevent it on the castings.