Valves for the Flare System
Collects and safely combusts relief and blowdown gas from across the plant. Its valves must remain leak-tight for years while guaranteeing open-path reliability the one time the system is called upon.
What are the critical valves in a Flare System?
Knock-out drum liquid drain (Control Valves) — Automatic liquid-level draw-off from intermittent, often sour flare condensate. Purge gas control (Control Valves) — Maintains positive purge flow to the flare tip to exclude air ingress. Header isolation (where fitted) (Gate Valves) — Car-sealed or interlocked-open valves so the flare path is never inadvertently blocked.
Critical Valve Points
Knock-out drum liquid drain
Control Valves →Automatic liquid-level draw-off from intermittent, often sour flare condensate.
Purge gas control
Control Valves →Maintains positive purge flow to the flare tip to exclude air ingress.
Header isolation (where fitted)
Gate Valves →Car-sealed or interlocked-open valves so the flare path is never inadvertently blocked.
Unit-Level Valve Strategy
- Flare header isolation is avoided by design wherever possible - the header must always have a path to atmosphere; where isolation exists it is car-sealed or interlocked open
- Knock-out drum liquid level and drain valves must handle intermittent, often sour or pyrophoric condensate
- Water-seal and purge-gas control valves maintain a positive purge to keep air out of the flare tip - control-valve reliability here is a safety function, not a process one
Equipment in this Unit
Fluids in this Unit
Governing Standards
Related process units
Connected Engineering
Sourcing valves for a Flare System?
Send your unit valve list — we supply the full set (Control Valves, Gate Valves) with certification matched to API 521, in one PO.