We succeed in researching the large caliber hollow wall twine pipes production lines on the foundation of abundantly absorbing and digesting European technology. Acquire many items of national patens. The pipes we produced is base on high density PE as main material. The rectangle pipes are extruded by the first extruder and then enter into twine from machine, at the same time, the second extruder spray the rubber strips and then squeeze to reunite it, its outside wall is neat and smooth. Specification is 400-2200mm. according to different usage term, the hardness degree of ring is divided into four grades and the Max can reach 16KN/m2. it is suitable for the sour alkali liquid below 10%.this kind of pipes have many extremely excellent characteristics, such as corrosion resistant light, easy to fix, long life(50 years), and etc. it can substitute the pipes made of high energy consumption material(cement, cast iron, porcelain and ceramics, and etc. it is widely used for sewer in superhighway, municipal construction, flats, athletic field, square, mine agriculture, bridges and etc.