High-Performance Flexible Wedge Gate Valve: The Versatile Industry Standard

Essential Specs:

Design Standard: API 600 / API 603 / ASME B16.34
Pressure Class: Class 150 – 2500 (PN20 – PN420)
Wedge Type: One-piece Flexible Wedge (U-Groove)
Sealing: Metal-to-Metal, Bi-directional

Engineered to Prevent Seating Jams and Adapt to Pipe Stress

A Flexible Wedge Gate Valve features a one-piece wedge with a circumferential groove cut into the center. This design allows the wedge to slightly “flex” as it enters the seat. Unlike a rigid solid wedge, the flexible wedge can adapt to changes in seat angle caused by pipeline stress or temperature fluctuations.

Core Advantages:

Prevention of Seating Jams: The flexibility allows the wedge to release more easily from the seats, even if the valve was closed while hot and opened after cooling.
Superior Sealing Integrity: By conforming better to the seat faces, the flexible wedge compensates for minor misalignments, ensuring a tighter seal than a solid wedge.
Cost-Effective Performance: It offers much higher reliability than a solid wedge but at a lower cost than a complex split wedge or parallel slide valve.

Key Design Features

Tapered U-Groove Design: The precision-machined groove provides just enough elasticity to ensure perfect seat contact without compromising the structural strength of the wedge.
OS&Y (Outside Screw and Yoke): Protects the stem threads from the process media, ensuring long-term smooth operation and easy lubrication.
Integral Body Guides: Heavy-duty ribs inside the valve body ensure the wedge stays aligned through its entire travel, preventing seat rubbing and ensuring low-torque operation.
Anti-Blowout Stem: Engineered for safety, the stem design prevents blowout under high-pressure conditions, meeting global safety standards.

Technical Specifications

Feature	Standard Configuration	Optional Upgrades
Size Range	2″ – 60″ (DN50 – DN1500)	Large Bore Customizations
Body Materials	A216 WCB, LCB, WC6, WC9	CF8, CF8M, CF3M, Duplex
Stem Material	410 Stainless Steel (Standard)	17-4PH, XM-19, Monel
Seat Design	Renewable Threaded or Welded Seats	Integral Seating
Bonnet Connection	Bolted Bonnet (BB)	Pressure Seal (PSB) for Class 900+

Wide-Ranging Industrial Applications

The Flexible Wedge Gate Valve is the “go-to” solution for general-purpose isolation in:

Oil & Gas Pipelines: Reliable shut-off for crude oil and gas transport.
Power Generation: Used in cooling water and secondary steam cycles.
Chemical Plants: Specified in stainless steel for handling varied chemical flows.
Water Treatment: Heavy-duty isolation for municipal water and desalination plants.

Compliant with: API 600 (Heavy Duty), API 598 (Test), ASME B16.10, and NACE MR0175 (Sour Service).

Flexible Wedge Gate Valve: Frequently Asked Questions

Q: Why should I choose a Flexible Wedge over a Solid Wedge?
A: A solid wedge is prone to “sticking” if the temperature changes. A Flexible Wedge has enough “give” to prevent sticking while still providing a robust, high-pressure metal seal.
Q: Is this valve suitable for steam?
A: Yes, for low to medium pressure steam. However, for high-pressure/high-temperature main steam lines, our Parallel Slide Gate Valve is often preferred to prevent thermal binding.