Metal Seated Rising Stem Gate Valve

Industrial plants that manage high-temperature steam, superheated water, and abrasive slurries demand gate valves engineered for extreme reliability. The Rising Stem Gate Valve with Metal Sealing Surface is a field-proven solution built to excel in these punishing services. Its rising stem mechanism positions operating threads securely outside the pressure envelope, shielding them from process fluids and eliminating the galling, corrosion, and clogging that routinely disable non-rising designs. As the handwheel rotates, the stem visibly lifts above the yoke, giving operators an unmistakable at-a-glance indication of whether the valve is open or closed—a critical safety advantage during lockout/tagout procedures. Suitable for both horizontal and vertical installations, this configuration fully complies with ASME B31.1 power piping and B31.3 process piping codes. The metal seating surfaces are factory-lapped and hardfaced with cobalt-based alloys, achieving hardness values above HRC 40, which sustains bubble-tight shutoff even after thousands of cycles in erosive service.

The Metal Seated Rising Stem Gate Valve integrates a flexible or solid wedge that self-aligns to compensate for body distortion caused by thermal cycling or pipe stresses. In applications where resilient-seated valves soften, deform, or delaminate, the metal-to-metal contact faces maintain structural stability and seal tightness. This extends mean time between repairs on lines carrying flashing condensate, molten salts, coking hydrocarbons, and particulate-laden fluids. A backseat design allows repacking of the stem while the valve is fully open and under full rated pressure, dramatically reducing downtime. Full-bore versions accommodate pigging and inline inspection tools; reduced-bore versions optimize weight and cost for less demanding duties. The valve accepts a complete range of actuators, from bevel gears and electric multi-turn units to hydraulic cylinders, and can be delivered with fire-safe certification to API 6FA or ISO 10497. Every valve undergoes hydraulic shell testing at 1.5 times rated working pressure and seat leakage testing at 1.1 times, backed by 3.1 material certificates per EN 10204 and full traceability from melt to shipment.

Performance Highlights

• External rising stem acts as a position indicator and keeps threads clean
• Stellite or tungsten carbide hardfacing on seats and wedge edges combats galling and wire drawing
• Backseat bushing permits live gland packing replacement without line shutdown
• Optional bypass equalization reduces operating torque on large-diameter valves
• Flexible wedge gate absorbs piping misalignment and prevents thermal binding
• Anti-blowout stem engineered for full containment of internal pressure
• Compatible with sour service and H₂S environments per NACE MR0175/ISO 15156
• Cryogenic configurations with extended bonnets available down to -196°C

Detailed Technical Specifications