Patent ID: 7137653
Filing Date: 2006-11-21
Classification: F16L

Abstract:
1. A pipe joint comprising a. A first pipe comprising a pipe bell and a bell groove disposed annularly within the pipe bell, said bell groove being bounded on an axially outward side by a bell thrust surface, b. A second pipe comprising a pipe spigot and a weld bead located on the pipe spigot, said pipe spigot located partially within the pipe bell in a position in which the weld bead is further, by an axially measured distance, within the pipe bell than is the bell thrust surface, wherein the pipe spigot is radially separated from the pipe bell at a location around the pipe spigot periphery by an annular gap, and c. A locking ring being located between and in substantially continuous contact with the bell thrust surface and with the weld bead, which bell thrust surface and weld bead are separated by a gap having different measurements when measured at different locations in the pipe joint, in which the locking ring twists in response to angular displacement of an axis of the first pipe from an axis of the second pipe.