A pressure relief valve opens automatically when pressure exceeds its set point and recloses when pressure falls. It is the last line of protection on a vessel or line, which is why its history matters as much as its condition.
Every pressure vessel, every compressor and every thermal expansion section has one. Plants keep large relief valve populations and rotate them through test and repair, which produces a continuous stream of removed, spare and superseded valves.
We buy safety relief valves in any quantity — single items, mixed pallets or whole cribs, including valves that need repair and assemblies that are missing parts. We do not require a clean inventory before reviewing a list.
| Common patterns | Conventional and balanced bellows, Pilot operated relief valves, Spring loaded safety valves for steam, Thermal relief and small-bore patterns |
|---|---|
| Typical service | Refinery and petrochemical, LNG and gas processing, Power generation |
| What we look at | We ask for the set pressure, the capacity or orifice designation, the inlet and outlet sizes, the body and trim material, and whatever test or repair records exist. Then we look at the condition of the disc and nozzle and whether the bonnet has been disturbed. |
| What to keep | Keep the valve complete with its cap, lever and any test tag, and keep the paperwork with it. A relief valve with no record of its last set pressure is still buyable, but the price reflects the missing history. |
Patterns and variants
What turns up most often
Variants matter because they change the buyer pool. A standard pattern sells to a rebuilder or a plant with the same service; a specialised trim sells to a much smaller group but often at a higher price. If you are unsure which variant you have, the nameplate or the trim marking will usually say.
Before it leaves site
How to protect the value
Keep the valve complete with its cap, lever and any test tag, and keep the paperwork with it. A relief valve with no record of its last set pressure is still buyable, but the price reflects the missing history.
Where they come from
Industries and services
- Refinery and petrochemical
- LNG and gas processing
- Power generation
Most of the surplus we see comes from plants that have replaced equipment for a reason that has nothing to do with the valve: a unit was re-rated, a line was re-piped, a control loop was upgraded or a project was re-scoped. The valve is simply the part that has to move.
Related patterns
Other valve types
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Read →Questions sellers ask
Do you buy relief valves without test certificates?
Yes. Many plants have valves that were removed before records were digitised. We will buy them on condition and identification, but be clear about what paperwork exists rather than implying there is more.
Can you buy valves that are out of test?
Yes. Out-of-test relief valves are normal surplus. We are buying the valve, not certifying it for service, and we do not represent that any valve is fit for reuse.
What about relief valves with the set pressure changed?
That is common and not a problem. Tell us the current set pressure if it is stamped or tagged, and we will treat it as the fact it is.