Engineered for the most critical isolation and flow control applications in high-temperature power generation, the BS 1873 Butt Welded Integral Forged F11 Pressure Seal Globe Valve represents the ultimate solution for high-pressure steam systems.
Compliant with the stringent British Standard BS 1873, this globe valve features an integral forged ASTM A182 F11 body (1.25Cr-0.5Mo alloy steel), eliminating casting defects and providing superior structural integrity under extreme thermal cycling. Designed specifically for power stations, the pressure seal bonnet utilizes internal system pressure to dynamically enhance sealing integrity as pressure increases. Coupled with butt-welded end connections, this valve ensures smooth operation, zero-leakage isolation, and reliable performance in extreme high-pressure environments.
Key Features & Benefits
• BS 1873 Compliance: Designed and manufactured strictly to BS 1873 standards for steel globe and globe stop valves, ensuring dimensional compatibility, structural safety, and reliable performance in global power infrastructure.
• F11 Forged Steel Construction: Manufactured from high-grade ASTM A182 F11 die-forged steel. The continuous grain flow provides unmatched tensile strength, fatigue resistance, and excellent high-temperature creep resistance.
• Pressure Seal Bonnet Design: Utilizes a self-energizing pressure seal structure. As internal steam pressure increases, the sealing force increases proportionally, ensuring zero leakage even during rapid startup and shutdown transients.
• Butt Welded End Connections: Features smooth butt-welded ends (per ASME B16.25 or BS 1873) to provide leak-proof joints, superior flow characteristics, and enhanced structural strength in high-pressure piping systems.
• Stellite Hard-Faced Trim: Seat rings and disc seating surfaces are overlaid with Stellite 6 (Co-Cr-W alloy) to resist severe erosion, corrosion, and galling in high-temperature steam flows up to 600°C.
Technical Specifications
Parameter | Specification |
Valve Type | Pressure Seal Integral Forged Globe Valve |
Design Standard | BS 1873, ASME B16.34, E101 |
Body Material | ASTM A182 F11 (Integral Forged) |
End Connection | Butt Weld (BW) per ASME B16.25 |
Pressure Rating | Class 1500 to 2500 (PN 260 - PN 420) |
Size Range | 2" to 10" (DN50 - DN250) |
Temperature Range | -29°C to +600°C |
Actuation | Manual Gear / Multi-turn Electric Actuator |
Testing & Inspection | BS 6755, API 598, NACE MR0175 (Sour Service Available) |
Applications
This high-performance forged globe valve is widely deployed in:
• Thermal Power Plants: High-pressure feedwater control, main steam bypass, and boiler drain systems.
• Supercritical/ Ultra-Supercritical Units: High-temperature and high-pressure steam flow regulation and isolation.
• Nuclear Power Facilities: Non-nuclear auxiliary steam and water control systems.
• Heavy Industrial Boilers: High-pressure steam generation and distribution networks.
FAQ Section
Q: What is the advantage of using F11 forged steel for power station globe valves?
A: ASTM A182 F11 (1.25Cr-0.5Mo) is a low-alloy chromium-molybdenum steel specifically designed for high-temperature service. The integral forging process aligns the grain structure, providing superior mechanical strength, excellent creep resistance, and higher safety margins in extreme Class 2500 power station applications compared to cast valves.
Q: How does the pressure seal bonnet work in high-temperature environments?
A: Unlike traditional bolted bonnets, the pressure seal design uses the internal media pressure to push the seal ring against the bonnet and body. The higher the system pressure, the tighter the seal becomes. This prevents the bolt-creep and leakage issues often seen in high-temperature thermal cycling.
Q: Why choose BS 1873 standard over API standards?
A: BS 1873 is specifically tailored for steel globe and globe stop valves in the petroleum, petrochemical, and allied industries. It provides strict guidelines for material specifications, sealing designs, and testing requirements, ensuring high reliability and compatibility for European and international engineering projects.
