White paper: When it makes sense to equip a plant with pilot-operated safety valves.
You wish to increase the operating pressure of your plant and thus also its efficiency? You wish to reduce media loss during discharge, or to minimize it when operating near set pressure?
Depending on the regulations and the type of medium, a system is usually operated at 85 - 90 % of the maximum permissible operating pressure. The reason for this is linked to spring-loaded safety valves, because the operating pressure of the equipment being protected must be lower than the closing pressure of the valve. Most manufacturers and the regulations recommend a difference of 3–5 % between closing pressure and operating pressure to ensure a clean closing of the valve and to optain a good seat tightness once again.
Pop-action pilot-operated safety valves such as the LESER Type 811 open and close abruptly. This valve opens with an overpressure difference of 1 %. It closes at a pressure of 97 % of the response pressure and can further be adjusted down to 85 %. Thanks to the opening pressure difference of 1 % and the closing pressure difference of -3 %, the procedure is significantly shorter than with a spring-loaded safety valve. As a result, loss of medium is reduced.
Pilot operated safety valves can reliably secure high back pressures and large mass flows at high pressures at the same time. Discover these and other specialist topics such as installation height, weight reduction or limits of soft seals in the new LESER white paper on pilot operated safety valves.