Saturday, July 6, 2019

The Basics of Pilot Operated Tank Relief Valves

When liquid is pumped in, storage tanks are pressurized and the current tank vapor is compressed. Tanks are also pressurized owing to higher ambient temperatures that cause the vapor of the tank to expand. Pilot operated pressure relief valves are mounted on tanks to mitigate harm caused by these growing tank vapors to avoid structural harm arising from overpressure.

Here is an outstanding animation, courtesy of Cashco, showing how a relief vent operated by a pilot valve protects a storage tank from overpressurizing during a pump-in condition or during rising ambient temperatures.

For more information on pilot operated tank relief valves, contact Arjay Automation at or by calling (800) 761-1749.