Socket welded flanges are commonly used for small-bore piping. The socket-welded flange is susceptible to crevice corrosion, wherein the gap at the pipe to socket interface is a crevice exposed to the process fluid. The socket weld flange is bored to the ID of the pipe and counter bored is slightly larger than the pipe to allow the pipe to be inserted and welded in place. They allow a pipe to fit inside a machined socket of a flange prior to welding. The pipe slips in upto the end of the socket and is welded on the outside with a fillet weld. This flange pipe fits into the recess to allow smooth flow through the flange. They are ideal for small diameter high-pressure applications.