At what pressure are extra heavy valves required to be installed?

Extra heavy valves are required to be installed at a pressure of 100 psig and above due to safety and operational integrity considerations. At this pressure level, the stress on the valves and piping systems increases significantly, necessitating the use of more robust components to safely handle the mechanical and thermal stresses involved.

The use of extra heavy valves helps ensure that they can withstand higher pressures without risk of failure, leakage, or other safety hazards. This is especially important in high-pressure systems where the consequences of valve failure can be severe, including potential injuries or significant damage to equipment and property.

Valves designed for lower pressure ratings, such as those typically found in operations below 100 psig, may not provide the same level of safety and durability under the increased demands posed by higher pressure systems. Therefore, the requirement for extra heavy valves at 100 psig ensures compliance with safety codes and best practices in boiler operations.