Plastic injection molding machines inject molten plastic into molds through injection devices, suitable for producing various complex shaped plastic products. A plastic extrusion molding machine extrudes molten plastic through an extrusion device to form continuous plastic products, such as pipes, bars, etc. Plastic blow molding machines use compressed air to blow molten plastic into the desired shape of plastic products, suitable for producing hollow plastic products. Compressors and transfer molding machines are mainly used for the molding of thermosetting plastics, which solidify the plastic in the mold by applying pressure.