... production of screw barrel type:1. injection screw barrel, injection Molding screw barrel,screw tips/screw nozzle,2. single screw barrel3. Twin screw barrel4. Twin Conical screw and barrel(Co-rotating,Counter)5. Twin Parallel screw and barrel Co ... emission area is enlarged, the cooling is rapid.4, The double screw extruder system can produce PVC plastic pipes, profiles, sheets, boards ...