?? ???????? ???? ?? ?? ?? is mainly used in manufacturing the pipe for agricultural and constructional plumbing, cable laying etc. This PVC pipe extrusion line is composed by conical twin-screw extruder, mould, vacuum calibration tank, haul-off, cutter and staker etc. The extruder and haul-off adopt imported AC frequency control device, vacuum pump and haul-off motors adopt high-quality brand.