The Metalock process is specifically intended for the repair of cracked or broken cast iron. It is a highly engineered process in which the damaged piece is restored to its original strength through the insertion of high strength alloy "keys" and "studs" and other special components in such a way that the crack pieces are "locked together".

This repair process is designed to overcome the well-known problems encountered when trying to repair cast iron using heat based methodssuch as welding and brazing.

Since Metalock repairs do not involve any heat there is no distortion and no new stresses - which often cause additional failure.