Valve TypesFull Glossary

PRV / PSV (Pressure Relief Valve / Pressure Safety Valve)

A valve that automatically opens when system pressure exceeds a set point, relieving excess pressure to protect vessels and pipelines from overpressure failure. PRV = modulating; PSV = snap-acting (full-lift). Designed to API 526 (flanged) or ASME Section VIII. Must be sized for the worst-case relief scenario.

Related Terms

Safety ValveAPI 526Pilot-Operated Safety Valve

Frequently Asked Questions

What is a PRV / PSV (Pressure Relief Valve / Pressure Safety Valve)?

A valve that automatically opens when system pressure exceeds a set point, relieving excess pressure to protect vessels and pipelines from overpressure failure. PRV = modulating; PSV = snap-acting (full-lift). Designed to API 526 (flanged) or ASME Section VIII. Must be sized for the worst-case relief scenario.

What is a PRV / PSV (Pressure Relief Valve / Pressure Safety Valve) used for?

PRV / PSV (Pressure Relief Valve / Pressure Safety Valve)s are used in industrial piping systems for on-off isolation, flow control, or backflow prevention depending on the valve type. They are selected based on the process fluid, operating pressure and temperature, required shutoff class, and pipeline size. Vajra Industrial Solutions supplies PRV / PSV (Pressure Relief Valve / Pressure Safety Valve)s certified to API 6D, ASME B16.34, and other applicable standards.

How do I select the right PRV / PSV (Pressure Relief Valve / Pressure Safety Valve) for my application?

Selecting the correct PRV / PSV (Pressure Relief Valve / Pressure Safety Valve) requires specifying: (1) nominal pipe size (NPS/DN), (2) pressure class per ASME B16.34, (3) body and trim material based on fluid compatibility and temperature, (4) end connections (flanged RF/RTJ, butt-weld, socket-weld, or threaded), (5) required certifications (API 6D, ISO 9001, fire-safe API 607). Contact Vajra Industrial Solutions at sales@vajravyuh.com with your specifications for a quote.

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