Wedge type gate valves form the backbone of reliable isolation in critical piping networks, combining straight-through flow with a resilient metal-to-metal wedge seal. Within this family, three primary designs meet virtually every operational requirement. The Solid Wedge Gate Valve employs a single-piece robust disc, making it the preferred choice for high-temperature steam lines and high-pressure oil transmission where rigidity prevents disc deflection. For applications subject to thermal cycling, the Flexible Wedge Gate Valve integrates a split disc with a flexible rim, allowing the gate to conform to seat distortion without sacrificing seal integrity. Where zero leakage is non-negotiable despite temperature fluctuations, the Double Wedge Gate Valve provides individual wedge discs that expand and contract independently, maintaining a bubble-tight closure. These valves are extensively deployed across refining, chemical processing, district heating, liquefied natural gas (LNG) terminals, and mining slurry systems, where their full-bore design practically eliminates pressure loss and allows unimpeded pig passage for pipeline cleaning.
Our Wedge Type Gate Valve is fabricated in API-licensed facilities under ISO 9001:2015 quality management, with full compliance to API 600, API 6D, and ASME B16.34. The valve is available with either a rising stem and OS&Y configuration for visual position indication or a non-rising stem for limited-space installations. The gate itself is guided throughout the travel to prevent vibration damage, while the seat rings are seal-welded or threaded and hardfaced with Stellite® 6 or 21 to combat erosion and galling. Every unit undergoes a complete hydrostatic shell test, seat leakage verification, and functional cycling before release. Actuation packages range from standard handwheels and bevel gear operators to sophisticated electric multi-turn actuators with Modbus interface, pneumatic double-acting cylinders, and hydraulic drives, enabling integration into PLC and SCADA networks.
| Parameter | Solid Wedge Gate Valve | Flexible Wedge Gate Valve | Double Wedge Gate Valve |
|---|---|---|---|
| Size range | 2″ – 48″ (standard) | 2″ – 36″ | 3″ – 24″ |
| Max working pressure | Class 2500 | Class 900 | Class 600 |
| Typical temperature limits | -196°C to 650°C | -29°C to 425°C | -46°C to 350°C |
| Wedge construction | One-piece solid casting or forging | Two halves with integral flexible rim | Two fully independent wedges |
| Leakage class (API 598) | Zero visible leakage for liquid/gas | Zero leakage, compensates for body distortion | Bubble-tight, self-aligning even under thermal shock |
| Preferred service | Steam, high-pressure hydrocarbons, high-temperature media | Heat exchangers, steam traps, systems with frequent thermal changes | Vacuum, cryogenics, services with extreme and rapid temperature swings |
| Actuation compatibility | All types | All types | Manual, electric, pneumatic |
Each Wedge Type Gate Valve incorporates a backseat design that permits stem packing replacement while the valve is fully open and under full differential pressure, drastically cutting downtime. The two-piece gland and self-adjusting PTFE or graphite packing minimize fugitive emissions and meet ISO 15848-1 requirements. An anti-blowout stem retained by an internal shoulder adds a critical safety barrier. For cryogenic or high-temperature use, extended bonnets and special trim are specified to maintain operability and seal integrity. A bypass arrangement can be integrated to balance pressure across the wedge, reducing initial actuation torque in large diameter valves and preventing water hammer.
Our wedge gate valves undergo thorough documentation tracing—each order ships with a material mill certificate, pressure test chart, and dimensional record. Third-party witness hold points are accommodated during manufacturing, and NACE MR0175/ISO 15156 compliance for sour gas and oil environments is standardly available. With a global installed base in offshore platforms, refineries, and power stations, these valves deliver decades of maintenance-friendly service.