Pipe coupling seal

Claim 1

A coupling device comprising first tubular coupling member having an externally threaded first end section with an annular end face and a peripheral shoulder formed in the inside face thereof spaced inwardly of and facing in the direction of said annular end face, an internally threaded second tubular coupling member threadedly engaging said first coupling member threaded section and having an annular shoulder confronting said annular end face and delineating therewith an annular recess, an annular sealing member nesting in said recess and formed of a cold flowable polymeric resin and having an initial shape including an inner tubular body section and a reversely directed outer end flange forming an end cuff on said body section, and a pipe, coaxial with and projecting through said second coupling member and sealing member into said first coupling member member and in abutment with said peripheral shoulder, said pipe having a peripheral groove formed in its outer surface disposed substantially axially outwardly of said annular end face in response to said coupling members being screw tightened to longitudinally compress and to deform said sealing member to a shape dissimilar from its inital shape and radially expand it into tight engagement with said peripheral groove of said pipe and the inside face of said second coupling member and substantially fill the cavity defined by said annular end face, annular shoulder, and pipe outside face.