Shell Moulding

Abstract

The invention of shell moulding is the first major change in foundry technology for a great many years. The shell mould is a simple device consisting of a thin mould of sand held together by phenolic resin. This type of moulding has at least two advantages over the conventional moulds: the castings have smoother surfaces and more accurate dimensions, which means reduced machining, and the moulds can be made on automatic machines without skilled labour. During the last few years there has been a tremendous growth in the industrial application of shell moulding, the automobile industry, for example, uses it extensively.¹ When the process was first introduced, its value was thought to be limited to moulding non- ferrous objects, but recent work has shown that ferrous metals can also be moulded in this way.