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J-VALVES
Design Features
Low-Temperature Tough Materials: Key components including the body, disc, and stem are made of low-temperature carbon steel or austenitic stainless steel such as ASTM A352 LCB/LCC, A350 LF2, A182 F304/F316. Cryogenic treatment is applied to guarantee impact toughness and resistance to brittle fracture at low temperatures.
Extended Bonnet Design: The bonnet features an extended neck structure, keeping the packing box area away from cryogenic media to prevent packing hardening and failure at low temperatures, while reducing cold loss and frost formation on the outer valve body surface.
Back Seat Structure: In the fully open position, the disc engages with the back seat on the bonnet to provide a reliable seal, allowing online packing replacement and improving maintenance safety.
Hardfaced Sealing Surfaces: Seat and disc sealing surfaces are hardfaced with Stellite alloy or made of solid carbide, resisting cryogenic erosion and wear to extend service life.
Low-Emission Packing System: A combination of flexible graphite, PTFE, or special low-temperature packing is used, together with a live-loaded packing gland design, ensuring dynamic sealing performance at low temperatures and meeting low-emission requirements.
Disc Guiding Structure: The disc is equipped with upper and lower guiding ribs or guiding sleeves to ensure stable alignment during opening and closing, reducing vibration and wear, making it suitable for high differential pressure conditions.
Flanged Connections: RF raised face or RTJ ring-type joint flanges are applied, complying with ASME B16.5, providing reliable sealing and easy connection to cryogenic piping systems.
Pressure Relief Hole Design: A pressure relief or balancing hole is provided in the disc to equalize body cavity pressure when the valve is closed, reducing operating torque and preventing abnormal overpressure.
Cold Insulation Structure: The outer body can be fitted with supports for insulation layers, facilitating on-site cladding with polyurethane or PIR insulation materials to minimize cold bridging effects.
Technical Specifications
Size Range: 1/2″ to 24″ (DN15 to DN600)
Pressure Class: Class 150 to Class 1500 (PN20 to PN250)
Temperature Range: -29℃ to +425℃
Body: ASTM A352 LCB, LCC, LC1, LC2, LC3; A350 LF2; A182 F304/F316
Disc/Seat: A351 CF8/CF8M, A352 LCC with Stellite hardfacing, solid carbide
Stem: A182 F304/F316, 17-4PH, XM-19
Packing: Flexible graphite, PTFE, special braided low-temperature packing
End Connections: Flanged (RF/RTJ), optional butt-welded (BW) extension pipes
Operation: Manual (handwheel / impact handwheel), gear operator, electric, pneumatic
Design Standards: BS 1873, API 602, ASME B16.34
Testing Standard: API 598
Applications
LNG Industry: Isolation and control of cryogenic media at LNG terminals, liquefaction plants, regasification stations, and tanker loading/unloading systems.
Air Separation Units: Transport and control of liquid oxygen, liquid nitrogen, liquid argon, and other cryogenic gases in air separation equipment.
Cryogenic Storage & Transportation: Inlet/outlet pipelines and safety relief systems for cryogenic tanks, tank trucks, and marine vessels.
Petrochemical Industry: Production, storage, and transportation systems for low-temperature cracking media such as ethylene and propylene.
Energy & Power: Critical valves for LNG peak-shaving stations in gas-fired power plants and liquid hydrogen storage and transportation systems for hydrogen energy.
Advantages & Value
Reliability in Cryogenic Service: Low-temperature tough materials and extended bonnet design ensure structural integrity and sealing reliability at extreme temperatures down to -196℃, eliminating the risk of low-temperature brittle fracture.
Safe and Convenient Operation: The back seat structure enables online packing replacement under pressure, and the extended bonnet prevents frostbite risks, complying with safety operation specifications for cryogenic valves.
High Cold Energy Efficiency: Optimized cold insulation interfaces and low-heat-conduction structures reduce cold loss and improve overall system energy efficiency.
Compliance with International Standards: Strictly manufactured in accordance with specialized cryogenic valve standards including BS 6364 and MSS SP-134, meeting qualification requirements for global LNG and air separation projects.
Customized Solutions: Special designs such as vacuum jackets, on-line defrosting, and low-temperature extension stems can be provided based on project requirements to adapt to complex on-site conditions.
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