What distance is recommended between each PRV in a series operation?

The recommended distance between each Pressure Relief Valve (PRV) in a series operation is 50 pipe diameters or an equivalent volume of pipe. This distance is crucial for ensuring the proper functioning of each PRV.

When PRVs are placed too close together, the discharge flow from one valve can interfere with the operation of the adjacent valve. This interference can lead to a situation where one valve may not relieve pressure adequately if the other is already discharging, potentially resulting in pressure build-up and compromising system safety. The specified distance helps maintain adequate spacing to reduce the risk of pressure surges or turbulence that could affect the performance of each valve.

The guideline of using 50 pipe diameters or equivalent helps to account for the flow characteristics of the fluid within the pipe and ensures that each PRV operates effectively under various pressure scenarios. This recommendation is a safety measure as it promotes the reliability and effectiveness of the pressure relief system in industrial applications.