The production line of PVC plastic pipes is mainly used to produce plastic PVC pipes with various diameters and wall thicknesses, such as agricultural water supply and drainage, building water supply and drainage, cable laying and so on. The unit is composed of conical twin screw extruder, vacuum setting box, tractor, cutting machine, turning frame or expander. Screw extruder and tractor adopt AC frequency conversion speed regulating device, vacuum pump and traction motor adopt products. There are two, three, four and six ways of traction. Saw blade or planetary cutting can be selected. Length gauge and thickening device can also be used. The performance of the unit is reliable and the production efficiency is high. The company can configure special equipment to produce spiral muffler and core foam pipe units according to customer requirements.