A gate valve opens by lifting a flat or wedge-shaped gate out of the flow path, so in the fully open position it is a straight-through pipe with almost no pressure loss. That is why it is the default isolation valve on water, steam, hydrocarbon and slurry headers, and why plants hold so many of them.
Gate valves are specified where tight shutoff and low pressure drop matter more than throttling. They are not meant to be part-way open: a partially open gate erodes and chatters. So the population in a plant is large, standardised and replaced in batches rather than one at a time.
We buy gate 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 | OS&Y rising stem, outside screw and yoke, Non-rising stem with inside screw, Resilient wedge, epoxy coated for water service, Solid and flexible wedge, cast and forged steel |
|---|---|
| Typical service | Water and wastewater, Steam and condensate, Refinery and terminal isolation |
| What we look at | We look at size and class, body and trim material, stem condition, seat tightness as described, whether the bonnet has been off, and whether the valve is a standard catalogued pattern or a one-off. Photographs of the nameplate and the seat faces, if the valve is open, tell us more than a description. |
| What to keep | Keep the handwheel, stem, bonnet bolting and the nameplate. A gate valve missing its handwheel is still saleable, but a gate valve with a cut or bent stem is a body and bonnet only. Do not cut the stem to remove a valve from a line: unbolt it instead. |
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 handwheel, stem, bonnet bolting and the nameplate. A gate valve missing its handwheel is still saleable, but a gate valve with a cut or bent stem is a body and bonnet only. Do not cut the stem to remove a valve from a line: unbolt it instead.
Where they come from
Industries and services
- Water and wastewater
- Steam and condensate
- Refinery and terminal isolation
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
Globe valves do the throttling and the frequent operation that gate valves should not. They are …
Read → Valve type Ball ValvesQuarter-turn, high flow, easy to actuate. Ball valves are the most commonly upgraded valve in a …
Read → Valve type Butterfly ValvesLight, cheap to replace, and produced in enormous numbers. Butterfly valves fill plant stores be…
Read →Questions sellers ask
Do you buy gate valves that have been in service for thirty years?
Yes. Age alone is not the test. Body wall thickness, stem straightness, seat condition and whether the pattern is still a standard size decide the value. Old cast iron gate valves in water service are among the most commonly purchased items we handle.
What about gate valves with the stem cut off?
They still have value as body and bonnet assemblies, and often as spare parts, but the price reflects that the stem and handwheel are gone. Send a photograph so we can see what remains.
Do you take mixed sizes in one lot?
Yes. Mixed lots are normal. A crib will have two-inch bronze valves next to twelve-inch cast steel, and we would rather review the whole list than have you sort it first.