Application-based Solutions Even Under Icy Conditions
Read how LESER’s Pilot Operated Safety Valves (POSV) guarantee a reliable valve function even under icy temperatures with high back pressure-ratios in order to save human life and the environment.
In the production facility of our customer, ice water at a temperature of 3°C need to be protected at 4.7 bar. In case of blow off, back pressures of up to 70 % of the set pressure may occur. This exceeds the range that can be compensated by spring-loaded safety relief valves. Additionally, the closing pressure should not be more than 7%, which is also outside of common closing pressure ranges for spring-loaded safety relief valves.
Our POSV finds remedy for this: Due to its construction, it works independently from back pressures. In this particular case a POSV Type 821 was installed. The blowdown for liquid media for this safety relief valve is at most 7 % of the set pressure, this fulfills the customer’s requirements exactly. Furthermore, the safety relief valve was equipped with additional accessories:
- Pilot supply filter: The pilot supply filter is connected upstream of the pilot valve and protects the valve against dirt.
- Manual blowdown: Manual blowdown allows a functional test of the main valve piston without having to shut down the whole plant. The manual blowdown bypasses the pilot valve so that the main valve can be opened manually.
The construction of the POSV allows counter pressures of up to 70 % and therefore the protection of plants outside the field of application for spring-loaded safety relief valves. This allows a reliable valve function even under icy conditions.
Find out more about our application-based solutions.