ESD Valves

Fail-safe isolation valves that close to stop hydrocarbon flow and isolate process segments on an emergency shutdown signal. Surface safety valves (SSV) on wellheads and process SDVs are the most common ESD final elements.

Fail-open depressurization valves that vent an isolated section to flare or atmosphere to reduce stored energy and limit fire exposure. They typically open as a paired action with SDV closure during shutdown.

High-reliability isolation valves used as the final elements in a High Integrity Pressure Protection System, which closes within a few seconds to prevent downstream overpressure in lieu of a relief device. These are usually engineered as SIL 3 redundant valve sets.

Wellhead surface safety valves and downhole subsurface safety valves (SSSV) that isolate the well to prevent uncontrolled flow. Tubing-retrievable and wireline-retrievable SSSVs are spring-fail-safe and hold open against control-line hydraulic pressure.

Spring-return pneumatic, hydraulic, or gas-over-oil actuators that drive the valve to its safe position on loss of motive power or signal. The actuator and its solenoid/quick-exhaust package determine stroke time and fail-safe direction.

Complete valve, actuator, and instrumentation packages certified for use within a defined Safety Integrity Level (commonly SIL 2 or SIL 3) per IEC 61508. They are supplied with failure-rate data and proof-test interval requirements.

Smart positioners and dedicated controllers that move the valve part-way and return it to verify operability without a full process trip. They extend proof-test intervals while raising the diagnostic coverage of the safety function.

ESD valves built to maintain shutoff after exposure to fire (fire-tested seats and stem packing) or to seal at low temperature for LNG and cryogenic duty. Construction follows fire-test and low-temperature qualification requirements for the chosen valve type.