Patent ID: 6920900
Filing Date: 2005-07-26
Classification: E03F,F16L

Abstract:
1. A pipe section for slip lining a sewer pipe line comprising: a pipe section wall having an outer surface having a non-circular cross-section; a spigot at a first end portion of the wall defining a shoulder on said wall; a protective ring surrounding the spigot for receiving a load from an external source for pushing the shoulder and thus, the pipe section along the sewer pipeline; wherein the wall comprises an inner portion adjacent to an outer portion, wherein the inner portion comprises a layer of chopped fibers and vinylester resin and wherein the spigot is part of the inner portion; and wherein the outer portion is formed from fiberglass reinforced resin, the pipe section further comprising a plurality of spaced apart outer annular ribs, each rib having a flat upper surface and a ramp surface extending from the outer portion to the flat upper surface, said rib width to thickness ratio being at least about 15:1.