Forged Socket Weld Union
The Socket Weld Union is a three-piece forged fitting used to create a separable joint in a socket weld piping system. It consists of two end pieces — each with a socket weld bore that accepts a pipe end — and a central union nut that draws the two end pieces together to form a leak-tight pressure seal using a metal ground joint face. The union allows the piping to be fully disconnected and reconnected by releasing and tightening the union nut, without rotating either pipe.
Unlike a full coupling, which creates a permanent weld joint, the socket weld union provides a demountable connection that can be broken for equipment removal, maintenance, inspection or future system modifications. Both pipe ends are permanently welded into the end sockets, while the union nut and ground joint face create the separable pressure seal at the centre of the assembly.
Cunimet Alloy International manufactures socket weld unions as fully forged three-piece sets, with both end pieces and the union nut machined from the same grade of material to ensure uniform corrosion resistance and mechanical properties throughout the assembly. The ground joint sealing faces are finish-machined to a close tolerance for reliable metal-to-metal sealing.