What is the purpose of using ground faced socket welded unions in NH3 piping?

Using ground faced socket welded unions in NH3 (ammonia) piping is primarily intended to ensure a leak-proof connection. The design of these unions allows for a smoother surface finish on the coupling faces, which minimizes the risk of leaks at the joint. This is particularly important in high-pressure systems like those transporting NH3, as even a small leak can lead to significant safety hazards and environmental concerns.

The ground faced finish creates a tighter seal upon welding, improving the quality and integrity of the connection. This strength and reliability are crucial in systems handling hazardous materials, where any failure could have serious implications. Thus, the emphasis on a leak-proof connection in NH3 piping systems is essential for both operational safety and compliance with regulatory standards.