Lap Joint flanges are used on piping equipped with lap joint stub ends or with lapped pipe. They may be used at all pressures and are available in a full size range.

These flanges slip over the pipe, and are not welded or otherwise fastened to it, bolting pressure is transmitted to the gasket by the pressure of the flange against the back of the pipe lap.

Lap Joint flanges have certain special advantages
¤ Freedom to swivel around the pipe facilitates the lining up of opposing flange bolt holes;
¤ Lack of contact with the fluid in the pipe often permits the use of inexpensive carbon steel flanges with corrosion resistant pipe or tubing
¤ In systems which erode or corrode quickly, the flanges may be salvaged for re-use.

Types of Lap Joint Flanges are