If NH3 is over what diameter is it classified as Sch 10?

In the context of high-pressure piping, the classification of piping systems is often based on the outer diameter of the pipes and the thickness of the walls. Ammonia (NH3), as a substance, has specific requirements for its containment which are dictated by safety and operational standards.

For ammonia, if the nominal diameter exceeds a certain threshold, it falls under a different schedule classification. In this case, pipes with a nominal diameter greater than 12 inches are classified as Schedule 10. This classification means that for pipes larger than this diameter, the wall thickness is determined to accommodate the pressure requirements while ensuring the structural integrity of the pipe.

The selection of Schedule 10 for pipes larger than 12 inches is based on the need to balance material cost and structural integrity. A Schedule 10 pipe provides sufficient strength to handle the pressures associated with ammonia transport without adding unnecessary weight or cost. Understanding these classifications is crucial for designing safe and operationally effective piping systems, especially under high pressure conditions.