The manufacture of castings involves highly skilled processes and the following describes each individual stage.
Stage 1
Our in house tool maker produces an aluminium die from customer drawings.
Stage 2
A wax mould of the component to be cast is produced by injecting high-technology wax into the aluminium die.
Stage 3
A number of wax components are then mounted on to a wax runner. Each runner may contain one large component or numerous small components..
Stage 4
The whole wax assembly is then dipped (or invested) into a water based binder and receives a Primary Coat of fine silica sand. This fine material is used first to give a smooth refractory surface finish and reproduce fine details.The coated assembly is then dried in a temperature controlled environment.
Stage 5
The Primary Coated assembly is then dipped into a water based binder and is coated with ceramic particles. This is then dried in a temperature controlled environment. Further layers are added and dried until the mould (investment) is the required thickness.
Stage 6
Once completely dried the mould is placed in a steam autoclave to melt out the wax; the process is sometimes called the lost wax process. Now just the ceramic shell remains.
Stage 7
The ceramic shell is then fired at approx 1000° C to remove any moisture and residual wax and to cure the shell. The shell is now a ceramic impression of the part to be cast.
Stage 8
Whilst the ceramic shell is hot, it is filled with molten metal, creating the metal casting.
Stage 9
Once the metal has cooled, the ceramic shell is removed leaving a casting that requires little or no finishing.
Stage 10
Next the castings are cut away from the runner and any necessary final post-processing (sandblasting, polishing, machining) is done to finish the casting.
