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J-VALVES
Design Features
F304 Stainless Steel Construction:The valve body is made of ASTM A182 F304 (0Cr18Ni9) stainless steel with 18‑8% chromium‑nickel content. It provides excellent atmospheric corrosion resistance and resistance to weak acids and alkalis, suitable for steam, water, oil products and general corrosive media, with outstanding oxidation resistance at elevated temperatures.
Extended Stem Design:The extended stem length is customizable according to operating conditions (typically 150–600mm, adjustable based on burial depth or insulation thickness). This places the handwheel/actuator at an easily accessible position, eliminating operation inside pits or insulation layers, and reducing maintenance difficulty and safety risks.
Flanged Connection:Both ends of the valve body are equipped with RF (Raised Face) flanges conforming to ASME B16.5 Class 300. For the 5.5-inch non-standard size, flange dimensions can be customized as required, or matched with 5-inch (DN125) / 6-inch (DN150) standard flanges to ensure reliable pipeline connection.
Low Operating Torque:The gate operates with linear vertical movement without rotational friction. Combined with anti-friction design of the stem nut, the operating torque is significantly lower than that of ball valves of the same size, enabling easy manual operation and supporting the use of small actuators.
Fire‑Safe Design:Compliant with API 607 standards. Graphite packing and metal sealing components maintain sealing integrity under fire conditions to prevent media leakage.
Blowout‑Proof Stem:The stem features an integral forged top‑mounted structure with anti‑blowout steps and sealing rings. Even if the packing gland accidentally loosens, the stem remains retained by the bonnet to ensure operational safety.
Graphite Packing Seal:The stuffing box uses flexible braided graphite packing or combined graphite rings, with temperature resistance up to +500℃ and above. It features low friction coefficient and excellent self‑lubrication, ensuring long‑term reliability of dynamic stem sealing.
Guide Rib Design:Internal guide ribs are integrated into the valve body to keep the gate aligned during lifting and lowering, ensuring even loading of sealing surfaces, avoiding jamming and scoring, and extending service life.
Technical Specifications
Nominal Size: 5.5″ (non‑standard, customizable); optional 5″ (DN125) or 6″ (DN150) standard sizes
Pressure Class: 300LB (Class 300, PN50), rated working pressure 51bar (5.1MPa)
Body Material: ASTM A182 F304 / F304L / F316 / F316L (forged stainless steel)
Temperature Range: -29℃ to +425℃
Body/Bonnet: ASTM A182 F304 / F304L / F316 / F316L
Gate: F304 / F316 + Stellite hardfacing (sealing surface) / integral hardening
Stem: F304 / F316 / 17‑4PH, high strength and corrosion resistant
Seat: F304 / F316 + Stellite hardfacing (sealing surface)
Packing: Flexible braided graphite / graphite rings / Inconel wire reinforced graphite (high temperature type)
Gasket: Stainless steel spiral wound gasket (316L/graphite filled) / RTJ ring joint gasket
Bolts: ASTM A193 B8 / B8M (corrosion‑resistant stainless steel)
Nuts: ASTM A194 8 / 8M
End Connection: Flanged (RF Raised Face), ASME B16.5 Class 300; optional BW butt‑weld ends
Face‑to‑Face Dimension: ASME B16.10
Operation: Manual (handwheel, sprocket, extension stem, post), pneumatic (linear stroke), electric (multi‑turn, on‑off / modulating), hydraulic
Design Standards: ASME B16.34, API 600, API 603
Test Standards: API 598, API 6D
Extended Stem Length: Customized per application, typically 150–600mm. For buried service, calculated based on pipe burial depth + operating clearance; for insulated lines, based on insulation thickness + operating clearance.
Applications
Buried Pipeline Systems:Used as 5.5-inch branch valves in buried pipelines for urban gas, heating, water supply and drainage. The extended stem places the handwheel above ground level, enabling operation without valve pits and reducing civil engineering costs.
High‑Temperature Steam Pipelines:Applied in 5.5-inch high‑pressure steam branches in power plants and chemical plants. F304 material withstands temperatures up to 500℃, and the extended stem prevents operators from contacting high‑temperature valve bodies, ensuring personnel safety.
Offshore Platforms and Marine:Used in 5.5-inch buried or under‑deck pipelines for seawater, fire fighting, bilge systems. F304 stainless steel resists seawater corrosion, and the extended stem allows convenient deck‑mounted operation.
Chemical Corrosive Media:Suitable for 5.5-inch pipelines conveying weak acids, weak alkalis, salt solutions and other general corrosive media. F304 stainless steel provides superior corrosion resistance over carbon steel, extending valve service life.
General Industrial Service:Ideal for isolation and shut‑off of 5.5-inch water, oil, gas and other media, especially in applications with restricted operating space, buried installation, or high‑temperature insulated conditions.
Advantages and Value
Operational Convenience:The extended stem locates the operating point above ground or insulation, avoiding pit work and high‑temperature contact. It reduces operational difficulty and safety risks, improving maintenance efficiency by more than 50%.
Stainless Steel Corrosion Resistance:F304 stainless steel resists atmospheric corrosion, weak acids and alkalis, suitable for steam, water and general corrosive media. Its service life is several times that of carbon steel valves, reducing replacement frequency.
Economic Buried Installation:Eliminates or minimizes valve pit construction, cutting civil engineering costs by more than 30%, especially suitable for urban areas with dense pipe networks.
High Temperature Adaptability:Graphite packing withstands temperatures up to +500℃, and F304 maintains stable high‑temperature strength, suitable for steam, hot oil and other high‑temperature services without thermal degradation of soft seals.
Extremely Low Flow Resistance:When fully open, the gate retracts completely into the bonnet, providing a straight, unobstructed flow path with nearly zero pressure loss, reducing pumping energy consumption and ideal for large‑flow isolation.
Reliable Sealing:The flexible wedge automatically compensates for sealing surface misalignment with consistent bi‑directional sealing, achieving zero leakage at Class 300 pressure to meet pipeline isolation and maintenance safety requirements.
Flexible Actuation:Low linear operating torque supports handwheel, sprocket, pneumatic, electric and other actuation methods, allowing easy integration into automated control systems for remote operation.
Custom Size Compatibility:The 5.5-inch non‑standard bore can be customized to match customer piping, or adapted to 5-inch / 6-inch standard flanges, fulfilling personalized requirements for special piping systems.
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