HDPE Large Diameter Hollow Wall Winding Pipe (200mm - 3000mm in dia.)produced by this Line has high ring stiffness ,high brunt intensity and low weight due to its unique???í???àstructure.In addtion, it has many advantages such as good creep deformation resistance, outer pressure resistance, erosion resistance(such as acid, alkali and salt etc.), long life of approximate 50 years, no pollution and so on. It has been widely used for sewerage and drainage in city, it will replace the cement pipe, cast iron pipe and other pipes. Its low cost of assembling, easy operation, easy connection and economical construction can make it wide foreground and market potential.