With three-layer co-extrusion die with spiral grooved core mandrel for option and the advanced technological prescription, the line is designed to produce PVC middle layer expanded pipe or PVC middle layer expanded pipe with screw-thread inwall. This kind of pipe features: lower density;sound-proof, when used as drain-pipe, water flow against the screw-thread inwall downwards, which solves the problem of noise. It is identified that PVC expanded pipe with screw-thread inwall can lower the noise for 5 to 7 Db than PVC expanded pipe, and 10 -15 Db than solid wall PVC pipe, and it is the most idea drain pipe fro building up to now.

This is equiped two twin-screw extruders to produce middle layer expanded pipe. High performance twin-screw extruder ensures the high efficiency extrusion.

Unique sctructure die ensures the production perfect.