RIM (Reaction Injection Moulding) is the low pressure injection of polyurethane resin into a mould. The tooling can be silicone rubber, resin board or Aluminium, depending on the part configuration and volume required. Silicone moulds can last from 50 to 100 castings, but using board or Aluminium can extend this to hundreds, sometimes thousands of parts.
The RIM process can also be used to produce silicone rubber components in a range of hardness up to 70 shore A. These are of particular interest where a higher degree of temperature resistance and flame retardancy may be required.