Parts constitute "220V Cooling Fan" cavity collectively referred to as molded parts, which includes die, punch, core, insert various shaped bars, various molded ring because the cavity in direct contact with high temperature and pressure of plastic, quality "220V Cooling Fan" is directly related to the quality of parts, thus requiring that it has sufficient strength, stiffness, hardness, wear resistance to withstand friction plastic squeeze pressure and streams and sufficient accuracy and surface finish, to ensure that the plastic surface of the light high and beautiful, easy mold release, general molding 2010 should be heat treated to "220V Cooling Fan" has more than HRC50 hardness, such as molded plastic produce corrosive gases such as PVC-hexene and the like. It should also select corrosion-resistant steel.