Lap flanges: The lap flanges are actually exactly the same as the slide flanges unless it is a radius between the hole and flange race.It is necessary for the radius to have the flange to accommodate the lap stub end.Typically, lap flanges and lap stubs mated together will assemble the system.

The socket butt flange is a similar sliding flange unless it has a hole and reverse hole size.Counter holes are slightly beater than the O.D. pipe matches, so that the pipe is inserted into the flange similar to the sliding flange.The diameter of the smaller hole is the same as the ID of the same pipe match.The limitation is a built-in hole, designed as a shoulder sleeve for piping stays at the bottom.This eliminates any flow limitation during use of socket welding flanges.