HDPE water/gas supply pipe production line, HDPE pipe extrusion machine/plant, HDPE pipe making machine This production line is mainly for producing large diameter HDPE/MDPE pipe. The pipe has some excellent features, such as heating resistant, aging resistant, high mechanical strength, environmental stress cracks resistant, good creep resistant and etc. It is a preferred gas conduit for ductwork systems between city and its suburb, water supply in city. Production line features: High efficiency extruder is designed for PE pipe, equipped with reducer which is high speed and low noise, adding material sect with cooling unit and sense reversing spiral grooved, different isomeric and undulant screw which allows great output, lower melting temp, and lower energy consumption. Composite spiral extrusion die-head assures that melting pressure and flux are uniformity and the surface of pipe is lubricity. Adopting vacuum calibrating and spray cooling baths, accurate calibration, fast cooling. The bath is made of stainless steel. Adopts two/multi caterpillar haul-off unit with speed adjusted by inverters. Adopting planetary saw, it can cut very large diameter and thick wall pipe. Adopts composite extrusion die-head, adding pipe-marking line.