When mounting safety valves together, what is a requirement regarding their size?

When mounting safety valves together, it is essential that the smaller valve must be at least 50% of the size of the larger valve. This requirement is crucial for ensuring that the system can adequately handle the pressure and prevent failure. Having a smaller valve that is proportionate in size helps maintain proper flow rates and effectiveness in pressure relief scenarios.

If the smaller valve is too small compared to the larger one, it might not fully relieve pressure when needed, potentially compromising the safety of the system. This guideline is based on engineering principles and industry standards that dictate how valves should be arranged to ensure reliable operation and provide sufficient capacity for pressure relief. Adhering to this ratio helps prevent situations where one valve could inadvertently be overwhelmed by the system's pressure without adequate backup from the additional valve.