... ; CE certificated; Energy saving 20% Application:Energy Supply Pipes Spiral Hose Extrusion LineHDPE Large Diameter Hollow Wall Winding Pipe produced by ... resistance, outer pressure resistance, erosion resistance(such as acid, alkali and salt etc. ), long life of approximate 50 years, no ... city, it will replace the cement pipe, cast iron pipe and other pipes. Its low cost of assembling, easy operation, ...