Transfer Molding

a method for manufacturing articles of various shapes from thermosetting plastics in which the material is softened (plasticated) in the injection cylinder (crucible), from which it is injected into the compression mold, where it hardens and assumes the configuration and dimensions of the article. In some cases, the injection cylinder may be loaded with plasticated material from an extruder. Transfer molding is performed in all-purpose presses, with a plunger for closing the mold and for injecting material into the mold, or in specialized presses, in which the mold is closed by one plunger and the material is injected by a second plunger.

Transfer molding is used for manufacturing articles of complex configuration and high dimensional precision, with small fittings, and with deep openings, as well as with large differences in wall thickness. The technology and equipment of transfer molding are intermediate between pressure molding of polymeric materials and injection molding.