L&T Pressure Seal Globe Valve
Ultimate Technical Guide to L&T Pressure Seal Globe Valves: Specifications, Features & Applications
In modern power generation and high-pressure processing facilities, conventional bolted-bonnet valves can experience body-bonnet joint leakage due to extreme thermal cycling and high pressure spikes. L&T Pressure Seal Globe Valves are designed specifically to overcome this challenge. Utilizing internal system pressure to tighten the bonnet seal, these valves deliver superior pressure containment, reliable throttling, and tight shut-off in extreme operating environments.
Technical Specifications Summary
|
Feature |
Specification Details |
|
Size Range |
2" to 24" (DN50 – DN600) |
|
Pressure Ratings |
ASME Class 900, 1500, 2500, and 4500 |
|
Design Standards |
ASME B16.34, BS 1873, API 623 |
|
Testing Standards |
API 598, BS EN 12266-1 |
|
End Connections |
Butt Weld Ends (ASME B16.25) and Flanged Ends (ASME B16.5 / B16.47) |
|
Operation Options |
Handwheel, Impactor Handwheel, Bevel Gear, Pneumatic, or Electric Actuator |
Material Construction & Trim Options
- Cast Carbon Steel: ASTM A216 Grade WCB / WCC (standard high-pressure service).
- Cast Alloy Steel: ASTM A217 Grade WC6, WC9, C12A (designed for high-temperature steam applications).
- Stainless Steel: ASTM A351 Grade CF8M / CF3M.
- Hardfacing & Trim: CoCr-A (Stellite 6) hardfaced body seats and disc seating faces to resist wire-drawing, erosion, and galling under high-velocity steam flow.
Key Engineering Advantages
- Self-Sealing Pressure Seal Bonnet: Unlike bolted-bonnet designs, as line pressure increases, the force acting on the pressure-seal gasket increases, securing an exceptionally tight body-to-bonnet seal.
- Superior Flow Regulation: Engineered disc geometry provides linear throttling and minimizes vibration during high-differential-pressure operation.
- Integral Backseat Design: Allows the stuffing box packing to be isolated while the valve is in the fully open position.
- Heavy-Duty OS&Y Yoke: Keeps stem threads isolated from the process fluid, reducing thread wear and preventing corrosion.
Primary Industrial Applications
- Thermal & Fossil Power Plants: Boiler feed lines, main steam isolation, superheater drains, and blowdown systems.
- Combined-Cycle Plants: Heat Recovery Steam Generator (HRSG) piping headers and bypass systems.
- Petrochemical & Refining: High-pressure hydrocracking, synthetic gas processing, and high-temperature chemical reactor loops.
