Process
About Shell Mould Casting
Shell Moulding is also known as shell mould casting , is an expendable mould casting process that uses a resin covered sand to form the mould.
As compared to sand casting, this process has better dimensional accuracy, a higher productivity rate.
It is used for small to medium parts that require high precision,
Shell mould casting is a metal casting process similar to sand casting, in that molten metal is poured into an expendable mould.
Shell mould casting requires the use of a metal die, oven, sand-resin mixture, dump box and molten metal.
Shell mould casting allows the use of both ferrous and non-ferrous metals, most commonly using a cast iron, carbon steel, alloy steel, stainless steel & other alloys.
Typical parts are small – to – medium in size and require high accuracy.
Die Development
A two piece metal pattern is created in the shape of the desired part, typically from iron or steel
Mould Creation
First, each pattern half is heated to 175 – 370 Celsius and coated with a lubricant to facilitate removal. Next the heated pattern is clamped to a dump box, which contains a mixture of sand and a resin binder.
Mould Assembly
The two shell halves are joined together and securely clamped to form the complete shell mould, If any core are required, they are inserted prior to closing the mould. The shell mould is then placed into a flask and supported by a backing material.
