Cold forging is the molding process under the recrystallization temperature of material, which is forging under the recovery temperature. In production, the forging of unheated blanks is called cold forging. Cold forging materials are mostly aluminum and some alloys, copper and some alloys, low carbon steel, medium carbon steel and low alloy structural steel at room temperature with small deformation resistance, good plasticity. Cold forging surface quality is good, size precision is high, can replace some cutting processing. Cold forging can strengthen the metal and increase the strength of the parts