Coupling

摘要

A coupling for sealing an outer cylindrical wall of a member of a fluid flow system extending along an axis. The coupling has a body and nut encircling the cylindrical wall which are configured to receive either a conventional O-ring or packing. The body includes a recess having a wall surface tapering at an angle in the range of 7 DEG to 20 DEG relative the axis and cooperates with the nut and cylindrical wall of the member to define an open area for receiving either an O-ring or packing.