For Poly Steel Pipe,the outer layer is galvanized steel pipe and the lining is PE pipe. And the outer can be coated with PE. It is not only has the advantage of high mechanical strength and good sealing ability due to the screwed connection as steel pipe, but also is with the advantage of low erosion, low impurity cumulation, low contamination, low liquid flow resistance as PE pipe. As a new generation environmental protection products, it is not only used in Chinese markets very popularly, but also is welcomed by USA, Malaysia, Thailand,Korea and peoples of other countries.