... the pipe and the Lap Joint then works as a backing ring. The main advantage of this type ... matching flange after the welds have been completed. A Lap Joint Flange is not suitable for areas with ... high external or dynamic loads. A Swivel Ring Flange should be used for this type ... F316/316L,F321) Alloy Steel (ASTM A182F1, F2, F5/A, F6/A, F9, F11, F12,F22, F91)· Normal Pressure: CLASS 150, ...