Pipe coupling having keys with camming surfaces

Abstract From the Canadian patent

A coupling for connecting two pipes together end to end is disclosed. The coupling includes a plurality of segments positionable circumferentially around the pipes. Each of the segments is attachable to one another end to end. Each of the segments has a pair of keys projecting radially inwardly toward the pipes. Each key is engageable with a circumferential groove on one of the pipes. Camming surfaces are positioned on the keys adjacent to the ends of the segments. Each camming surface preferably has an angularly oriented face that forms a wedge to provide a mechanical advantage when the camming surface engages the groove.