Pressure Relief Systems — Unspecified

Spring-loaded or pilot-operated valves that open at a preset pressure to discharge fluid and reseat when pressure falls. They are the primary code-required relief device on vessels and piping protected under ASME Section VIII.

Non-reclosing devices with a thin membrane that ruptures at a set burst pressure to provide instantaneous full-bore relief. They are used for fast overpressure events, corrosive or fouling service, or as an isolation barrier upstream of a relief valve.

Instrumented safety systems that sense high pressure and rapidly close dedicated shutdown valves to isolate the source before relief is needed. They are designed to a defined safety integrity level under IEC 61511 and can reduce or replace conventional relief capacity.

Pressure/vacuum relief vents, breather valves, and emergency vents that protect atmospheric and low-pressure storage tanks from overpressure and vacuum during filling, drawdown, and thermal changes, sized per API Standard 2000.

Relief headers, knockout drums, flare stacks, and vent stacks that collect and safely dispose of relieved fluids. They convert the discharge from relief devices into a controlled burn or dispersion path, with loads determined per API Standard 521.

Relief valves that use process pressure acting through a pilot to hold the main valve closed, allowing operation close to set pressure with tight seating. They suit high-pressure, high-flow, or backpressure-sensitive services.

Small relief valves that protect blocked-in piping, exchangers, and vessels against hydraulic expansion of trapped liquid from heat input. They relieve the limited volume generated by thermal expansion rather than full process flow.