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J-VALVES
Structural Features
Low-Temperature Tough Materials:The valve body is made of cryogenic materials such as ASTM A352 LCB/LCC (low-temperature cast carbon steel), A350 LF2 (low-temperature forged steel), or A182 F304/F316 (stainless steel, cryogenically treated). Cryogenic treatment at -196℃ in liquid nitrogen eliminates residual stress, stabilizes the austenitic structure, prevents low-temperature embrittlement and dimensional variation, and ensures toughness and reliability at extreme low temperatures.
Extended Bonnet Design:The bonnet length is customized according to the insulation thickness (typically 150mm–600mm), keeping the stuffing box and operating mechanism away from the cryogenic zone of the valve body. This prevents cold injury to operators, avoids interference between insulation layers and operation, and reduces freezing failure of the packing area caused by cold conduction.
Globe Valve Structure:The valve body features an S-shaped flow passage. The disc lifts vertically along the centerline of the seat, with short opening/closing stroke and low sealing surface wear. It is suitable for frequent operation and precise throttling control, and offers superior sealing performance over ball valves in
cryogenic service.
Disc & Seat Sealing:The sealing surfaces of the disc and seat adopt metal-to-metal sealing or Stellite hardfacing, providing excellent resistance to low-temperature erosion and wear. Reliable sealing is maintained after repeated cycles, with leakage rate up to API 598 zero leakage or ISO 5208 Rate A/B.
Low-Temperature Packing System:The extended stuffing box uses multi-layer PTFE/V-type graphite or special low-temperature packing. Combined with the cold isolation effect of the extended bonnet, it maintains the packing area temperature within an operable range and prevents freezing-induced leakage or operational failure.
Flanged Connection:RF (Raised Face) or RTJ (Ring-Type Joint) flanged connections are applied, conforming to ASME B16.5/EN 1092-1 standards, ensuring reliable installation and tight sealing under cryogenic conditions.
Stem Design:The rising stem structure is equipped with a low-temperature stuffing box sealing system. Stem threads are located outside the valve body (rising type), enabling easy observation of opening indication and meeting operational requirements in cryogenic service.
Fire-Safe Design:Complies with API 607 standards. In case of fire, metal-to-metal sealing and graphite packing retain adequate sealing performance to prevent massive leakage of cryogenic media.
Anti-Static Device:Built-in anti-static spring/steel ball structure conducts static electricity between the stem and valve body, preventing static accumulation caused by high-speed flow of cryogenic media.
Blowout-Proof Stem:The stem is designed with a lower anti-blowout shoulder, preventing the stem from being blown out by media pressure even in case of abnormal overpressure inside the valve.
Flow Direction Indication:A flow arrow is cast or marked on the valve body, indicating low-inlet and high-outlet flow direction to ensure correct installation, reduce operating force and protect sealing surfaces.
Insulation-Compatible Design:Reserved installation space for external insulation layers on the valve body, matched with the extended bonnet, ensures complete and interference-free insulation structure, minimizing cold loss and condensation.
Technical Parameters
Nominal Diameter: DN50 to DN400 (2" to 16")
Pressure Rating: PN20 to PN100 (Class 150LB to 600LB)
Temperature Range: -196℃ to +100℃
Body/Bonnet: ASTM A352 LCB/LCC (low-temperature cast carbon steel), A350 LF2 (low-temperature forged steel), A182 F304/F316 (stainless steel, cryogenically treated)
Disc: Body-matched material + Stellite hardfacing, or 13Cr stainless steel
Seat: Body-matched material + Stellite hardfacing, or body-hardened
Stem: F304/F316 or 17-4PH precipitation-hardened stainless steel (cryogenically treated)
Sealing Materials: PTFE/RPTFE/PCTFE (auxiliary seat sealing); special low-temperature graphite or PTFE V-type combination (stem packing)
Extended Bonnet: Body-matched material, length customized per insulation thickness
Gasket: Spiral-wound gasket (inner & outer rings) or special low-temperature gasket
End Connection: Flanged (RF or RTJ, conforming to ASME B16.5/EN 1092-1)
Operation: Handwheel (standard); optional gear operator, pneumatic or electric actuator (low-temperature type)
Design Standard: ASME B16.34
Test Standard: API 598, BS 6364 low-temperature test
Face-to-Face Dimension: Conforms to ASME B16.10
Applications
LNG Industry Chain: Used in low-temperature piping systems for LNG production, storage, transportation and regasification stations, providing precise regulation and reliable shut-off for cryogenic media, resistant to -162℃ LNG and -196℃ liquid nitrogen pre-cooling.
Large-Scale Air Separation Units: Applied in large-bore low-temperature pipelines for storage and transportation systems of air separation products such as liquid oxygen (-183℃), liquid nitrogen (-196℃) and liquid argon (-186℃).
Low-Temperature Chemical Industry: Used in transportation and reaction systems for low-temperature chemical media including ethylene (-104℃) and propylene (-47℃), preventing low-temperature leakage and cold injury risks.
General Cryogenic Service: Suitable for precise regulation, on/off control and reliable isolation of various low-temperature liquids and gases.
Advantages & Values
Excellent Sealing in Cryogenic Service:The linear flow characteristic of the globe valve enables fine flow regulation even at small openings. Its sealing performance is superior to ball valves under cryogenic conditions, making it ideal for applications requiring precise control.
Safe Low-Temperature Operation:The extended bonnet elevates the operating mechanism away from the cryogenic zone, effectively preventing cold injury and avoiding freezing-induced leakage or seizure in the packing area, ensuring safe operation and durable sealing in cryogenic service.
Reliable Cryogenic Materials:Low-temperature tough materials, after cryogenic treatment, maintain outstanding toughness and dimensional stability at -196℃, avoiding low-temperature embrittlement and leakage.
Optimized Insulation Compatibility:The extended bonnet integrated with insulation design ensures a complete, interference-free insulation structure, reducing cold loss and condensation and improving system energy efficiency.
Flow-Controlled Sealing Protection:The low-inlet and high-outlet flow design allows media pressure to assist sealing, delivering low operating torque during closing and preventing direct erosion of sealing surfaces by high-speed fluid.
International Standard Compliance:Meets global standards including ASME, BS and MSS, and passes certified low-temperature tests, satisfying procurement requirements for international cryogenic projects.
