This product using PEP/PFP coating pipes is prevented from many defects arising from upon welding (that would be incurred upon welding). To supply clean water service, these products are designed to fit for Earthquake-Resistant and nature settlement Design of Structures As a form of having welding ring to pipes, it is used to be tightly jointed with a large diameter pipe on landfill site including mainly waterworks. they are mainly used above 14 inch.