Gate Valves
A gate valve is an on/off isolation valve that opens and closes by raising or lowering a gate (wedge or slab) across the flow path. In the fully open position, the gate retracts completely out of the flow path, creating a full-bore opening with minimal pressure drop. In the closed position, the gate seals against two seats, providing bidirectional shutoff. Gate valves are not designed for flow throttling — they are isolation valves, used fully open or fully closed.
What Gate Valves Do in Oilfield Applications
Gate valves appear at multiple points in the wellhead and production system:
- Wellhead and Christmas tree — master valves, wing valves, and kill valves
- Flowlines — isolation valves for maintenance and pigging
- Manifolds — well selection and routing in production manifolds
- Separation equipment — isolation for maintenance and bypass
In wellhead service, gate valves are manufactured to API 6A. In flowline and facility service, API 600 or API 6D valves are used depending on pressure class.
Product Range
WNS Lowery supplies gate valves in carbon steel and stainless steel for oilfield and industrial service. The WNS Lowery valve range is 100% American-made and has been a standard of the oilfield industry for decades.
Available configurations:
- Standard carbon steel — sweet service
- Stainless steel — corrosive service
- Z-PEX coating option — heat resistance to 550°F, resistant to harsh corrosive chemicals
- Multiple elastomer options for seal compatibility with produced fluids
Sizes and pressure classes are available across the standard oilfield range. Contact Proxima for the full configuration matrix.
Key Specifications
| Parameter | Details |
|---|---|
| — | — |
| Body materials | Carbon steel, stainless steel |
| Coating option | Z-PEX — heat and corrosion resistant |
| Seal elastomers | Multiple options for fluid compatibility |
| End connections | Flanged, threaded, butt-weld |
| Standards | API 6A (wellhead), API 600 / API 6D (pipeline) |
| Origin | 100% American-made |
Suppliers
| Supplier | Products | Notes |
|---|---|---|
| — | — | — |
| WNS Lowery (Marsh Bellofram Group) | Gate valves — carbon steel and SS | American-made, oilfield and industrial service |
Why Source Through Proxima
Proxima stocks WNS Lowery gate valves in standard oilfield sizes for fast delivery to Azerbaijan and the wider Caspian region. We supply valves with full material certifications and test reports.
Frequently Asked Questions
Q: Can gate valves be used to throttle flow?
No. Gate valves are isolation valves — designed to be fully open or fully closed. Throttling causes erosion of the gate and seats, leading to premature failure. For flow control, use a choke valve or globe valve.
Q: What is the difference between a wedge gate and a slab gate valve?
A wedge gate has a tapered gate that wedges between angled seats — providing a tight shutoff under pressure. A slab gate (parallel gate) uses a flat gate against parallel seats, preferred in pipeline service where pigs must pass through the valve bore.
Q: Are WNS Lowery gate valves available with fire-safe certification?
Contact Proxima for current certification options. Specify your service conditions and any certification requirements when requesting a quote.
Q: Can Proxima supply gate valves for H₂S service?
Yes. Specify sour service requirements (H₂S concentration, temperature) when ordering. WNS Lowery valves are available with NACE-compliant materials for sour service.
