What Is a Socket Weld Flange?

A socket weld flange is a type of pipe connector that incorporates a socket into which a pipe is welded. The inclusion of a socket in the socket weld flange creates a connection that is much stronger than a comparable slip-on flange. The socket weld flange was designed to work on small size, high-pressure pipelines. This flange is very popular in chemical plants where a smooth-flowing connection is needed in all flange joints. The benefit of a flanged connection is that the pipe can be easily disconnected at the flange and reassembled just as easily.

When using a slip-on flange, the pipe must be beveled to allow a weld to be placed on the inside of the flange as well as the outside. This inner weld requires grinding to create a smooth-flowing connection. By using a socket weld flange, this grinding is not required to achieve a smooth flow of liquid through the connection. The socket is designed to have an inner lip that is the same width as the intended pipe to be inserted into the flange. This allows the pipe to be exactly lined up with the lip of the socket inside of the flange when the unit is assembled, creating a smooth transition inside the flange.

Another feature of the socket weld flange is the shoulder that is inside the socket. This shoulder allows the pipe to be slipped into the flange until it makes contact with the shoulder, making certain that the pipe is placed into the flange far enough. After the pipe makes contact with the shoulder, the welder can secure the flange to the pipe by placing a butt weld around the perimeter of the socket. The flush fit of the pipe against the shoulder inside the socket provides as much strength as an internal weld on a slip flange, but without the grinding that is associated with the inner weld.

By eliminating the need for the inner weld, a socket weld flange can save time in assembly while producing an equally strong connection. The thick socket also provides optimal flow by matching the inside bore of the socket with the inner diameter of the pipe, thus creating a smooth transition without matching. The socket weld flange is available in mild steel and stainless steel to be used with both food-grade pipeline as well as non-food-grade pipeline. The flange also works with both high-pressure and low-pressure applications.