1.Ring stiff SN(KN/m2):8,12.5,16 2.light weitht 3.simple intallation,good sealing and low cost of construction Buired steel band reinforced polyethylene (PE) spiral corrugated pipe for sewage is spirally twined, extruded and compounded into a unity in the production lines, taking polyethylene as the outer basic material and corrugate steel band which is coated with high-performance adhesive resin ...