At what diameter or larger is SS welded pipe in NH3 classified as Sch 10?

In the context of ammonia (NH3) piping systems, the classification of stainless steel (SS) welded pipe into schedule categories is crucial for ensuring safety and compliance with industry standards. The schedule number, indicating wall thickness, directly affects the pipe's pressure rating and overall performance.

For stainless steel welded pipe in ammonia service, it is established that piping with a diameter of 8 inches or larger is classified as Schedule 10. This classification is important because it reflects the specific requirements for thickness that ensure the pipe can handle the pressures and potential risks associated with ammonia transport and storage.

Pipes sized smaller than 8 inches typically have different standards regarding their wall thickness and pressure rating, which do not fall within the Schedule 10 classification for ammonia applications. Understanding these classifications is essential for professionals working with high-pressure piping systems, as using the correct schedule helps prevent failures and maintains safety protocols in ammonia handling processes.