US Patent 7306264 Pipe having a water-tight in-line bell

In a corrugated pipe comprising two sections joined by telescopically mating a male end of one section with a female end of the other section, an annular sealing element is fixed to the exterior surface of the male end and disposed to sealingly engage the interior surface of the female end. An annular band of reinforcing material is disposed around the exterior surface of the female end at a position along the longitudinal axis thereof that is in general alignment with the sealing element. The reinforcing material resists loss of sealing engagement between the female end and the sealing element during use of the pipe.