SW Flange (Socket Weld Flange) is contain a shoulder on the inside of the flange that acts as a guide to set the depth at which the pipe is welded to the flange. They are fabricated by inserting the pipe end into the flange until it bottoms out against the shoulder, and then retracting the pipe 1/8 in before welding it in place. This practice was originally employed to reduce cracking due to thermal stresses in stainless steel superheaters, but over the years has become standard practice for the installation of all socket weld flanges (SW Flange). Advantages of Socket Welding Flange:
The pipe does not require a bevel welding preparation.
There is no need for temporary positioning welding on time, as the principle of coordination ensures correct alignment.
Weld metal cannot penetrate the hole in the pipe.
They can be used instead of threaded joints, so the risk of leakage is much smaller.
Radiography does not apply to fillet welds; Therefore, proper welding and welding is very important. Fillet welds can be inspected by surface inspection, magnetic powder (MP) or liquid penetrant (PT) inspection methods.
Due to the lack of strict assembly requirements, and the elimination of butt welding end of the special processing, so the construction cost is lower than the welding head.
Main features of socket welding flange:
The groove on the inner diameter allows for a good fit of the pipe, allowing for smooth flow of the liquid
Suitable for small size and high pressure temperature conditions.
Similar to sliding flange, but must specify piping arrangements to be used for socket welding
The following figure shows the inner diameter of the socket weld flange. This flange happens to be the so-called insert flanges. This is a two-piece flange to allow the external flange rotation, easy to bolt hole alignment. SFF can provide these flanges and standard All-in-one socket welding flanges.