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J-VALVES
Design Features
Self-Sealing Bonnet Structure: The bonnet and body adopt a pressure‑activated self‑sealing design (such as lens gasket, triangular gasket, or C‑ring construction). Medium pressure acts on the sealing element to create a self‑energizing effect; the higher the pressure, the more reliable the seal, completely eliminating external leakage risks and suitable for ultra‑high‑pressure service.
Butt-Weld (BW) Connection: The body ends are connected to the pipeline by full‑penetration butt welding, forming a permanent high‑strength joint without flange gasket leakage points. It features excellent resistance to high pressure, high temperature, and vibration, making it ideal for critical pipelines.
Forged High-Pressure Body: Manufactured with an integral forging process, the material is dense and uniform, free of casting defects, and provides exceptional pressure‑bearing capacity, suitable for Class 1500 and higher pressure classes.
Plug-Type Disc: Standard design for general shut‑off and regulation service; sealing surfaces can be hardfaced with cemented carbide.
Needle-Type Disc: Precision regulation design with a conical needle head to achieve accurate control of small flow rates, suitable for throttling and instrument systems.
Solid Carbide Sealing Surfaces: Seat and disc sealing surfaces are hardfaced with Stellite alloy or made of solid carbide, resisting high‑temperature erosion, cavitation, and wear to extend service life.
Fully Guided Stem Structure: The disc is equipped with upper and lower guiding ribs or guide sleeves to ensure stable alignment during operation, reducing vibration and uneven wear, and adapting to high differential pressure conditions.
Low-Friction Packing System: Fitted with flexible graphite braided packing or high‑temperature‑resistant special packing, combined with an extended heat‑dissipating bonnet to keep the packing area away from high‑temperature media, protecting the packing and ensuring operational safety.
Technical Specifications
Size Range: NPS 1/2″ to 24″ (DN15 to DN600)
Pressure Class: Class 900, Class 1500, Class 2500, Class 4500 (PN150, PN260, PN420, PN760)
Temperature Range: -29℃ to +425℃
Body/Bonnet: ASTM A105, A182 F11/F22/F91, A182 F304/F316, F347
Disc/Seat: F11/F22/F91 with Stellite overlay, F304/F316 with Stellite overlay, solid carbide
Stem: F6a, F304, F316, 17‑4PH, Inconel 718 (high temperature)
Self-Sealing Elements: Mild steel, stainless steel, Inconel lens gaskets or C‑rings
Packing: Flexible graphite, graphite reinforced with Inconel wire, high‑temperature ceramic fiber
End Connections: Butt‑Weld (BW) conforming to ASME B16.25; Socket‑Weld (SW) available for small sizes
Operation: Manual (impact handwheel / sprocket), electric, pneumatic, hydraulic, electro‑hydraulic
Design Standards: ASME B16.34, BS 1873, API 602
Testing Standard: API 598
Applications
Petrochemical Industry: Shut‑off of high‑temperature, high‑pressure hydrogen and hydrocarbon media in hydrocracking, catalytic cracking, and reforming units.
Coal Chemical Industry: Control of high‑pressure, high‑temperature syngas and slurry media in coal gasification, coal‑to‑liquid, and coal‑to‑olefins plants.
Combined Cycle Gas & Steam Turbines (CCGT): Quick shut‑off and flow regulation in high‑pressure steam systems of heat recovery steam generators (HRSG).
Long-Distance Pipelines: Inlet and outlet isolation at pump stations and compressor stations for high‑pressure natural gas and crude oil transmission pipelines.
Advantages & Value
Zero External Leakage Reliability: The self‑sealing structure automatically enhances sealing performance with increasing medium pressure, and butt‑weld connections eliminate all external leakage points, meeting the strictest environmental and safety requirements.
High-Temperature Durability: Integral forged body, carbide sealing surfaces, and high‑temperature packing systems ensure stable long‑term operation up to +650℃.
Maintenance Safety: The back seat structure allows online packing replacement without system shutdown, greatly reducing maintenance costs and downtime losses.
Precise Flow Control: Globe valves offer superior linear flow characteristics compared to gate valves; with needle‑type discs, accurate regulation of very small flow rates can be achieved.
International Standard Compliance: Strictly manufactured in accordance with ASME, API, BS, and power industry standards, meeting qualification requirements for global energy and chemical projects.
Extreme Condition Customization: Special designs such as nuclear‑grade certification, low‑temperature tough materials, anti‑cavitation discs, and noise‑reduction cages can be provided based on project requirements.
