Extrusion is also called extrusion molding. It is a way to squeeze the heated resin through the mold and squeeze out the desired shape products by extrude. Extrusion is also sometimes used for molding thermosetting plastics and for molding of foamed plastics.The advantage of plastic is that the products can be extruded in various shapes. The production efficiency is high, and the production can be automated and continuous. The disadvantage is that the thermosetting plastics can not be widely used by this method, and the size of the products is easy to produce deviation.
Injection molding is also called injection molding. Injection molding is a method of injecting thermoplastic melt into the mold by injection molding machine, and then cooling and curing to get the product. Injection molding can also be used for molding thermosetting plastics and foam plastics. The advantages of injection molding are fast production, high efficiency, automatic operation and forming complex parts. It is especially suitable for mass production. The disadvantage is that the cost of equipment and mould is high, and the cleaning of injection molding machine is difficult.