Technical Datasheet: Cryogenic Bellows Seal Gate Valve
Product Name: Cryogenic Bellows Seal Gate Valve
Connection: Flanged Ends (ASME B16.5)
Taille nominale : 1.5 inches (DN40)
Pression nominale : Class 300 LB
Matériau du corps : Stainless Steel (CF8 / CF8M / CF3M)
- General Design Features
- Taper: Bellows-sealed gate valve, specifically designed for cryogenic services.
- Service Temperature: Designed for cryogenic applications down to -196°C (-320°F) (LNG, Liquid Nitrogen, Liquid Oxygen) .
- Seal Design: Zero-leakage to atmosphere via a primary welded metal bellows. A secondary graphite packing provides backup sealing.
- Bonnet Design: Extended bonnet construction to ensure the stem packing and bellows assembly remain above 0°C, preventing ice formation and seal failure .
- Cryogenic Treatment: All pressure-containing parts are subjected to deep cryogenic treatmentat -196°C to ensure dimensional stability and prevent austenite transformation .
- Back Seat: Integral back seat allows for repacking under pressure (if bellows fails) and protects the packing from direct media flow.
- Opération: Rising stem with non-rising handwheel for visual position indication.
- Applicable Standards & Specifications
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Item
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Standard / Specification
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Design & Manufacturing
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BS 6364 (Specification for valves for cryogenic service) , API 600, ASME B16.34, GB/T 44916
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Face-to-Face Dimensions
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ASME B16.10
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Flange Connection
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ASME B16.5 (Class 300 LB)
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Pressure-Temperature Rating
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ASME B16.34
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Testing & Inspection
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BS 6364, API 598, ISO 5208, GB/T 24925
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Bellows Standard
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ISO 15761 / BS EN 137-1
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Fugitive Emissions
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ISO 15848-1 (Optional)
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- Operating Parameters
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Item
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Spécification
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Taille
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1.5 inches (DN40)
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Pression nominale
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Class 300 LB (Max 51 bar @ ambient per ASME B16.34)
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Shell Test Pressure
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77 bar (Hydrostatic, 1.5 x Class 300 rating)
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Seat Test Pressure
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56 bar (Hydrostatic, 1.1 x Class 300 rating)
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Design Temperature
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-196°C to +80°C (Cryogenic service)
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Suitable Media
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LNG, LPG, Liquid Nitrogen (LN₂), Liquid Oxygen (LO₂), Liquid Argon, Ethylene
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Leakage Rate
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Zero leakage to atmosphere (bellows seal)
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- Bill of Materials (Stainless Steel Cryogenic Design)
Note: Materials are selected to meet BS 6364 cryogenic requirements .
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Item
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Part Name
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Material Specification
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1
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Corps
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ASTM A351 CF8M (316 Stainless Steel Casting)
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2
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Bonnet (Extended)
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ASTM A351 CF8M (316 Stainless Steel Casting)
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3
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Gate / Wedge
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ASTM A182 F316L with Stellite hardfacing (Co-Cr alloy)
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4
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Seat Ring
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Stellite hardfaced (integral with body)
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5
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Bellows
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ASTM A240 316L (Multi-ply Stainless Steel)
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6
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Tige
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ASTM A182 F316L (Austenitic Stainless Steel)
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7
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Body Gasket
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Spiral Wound 316SS + Graphite
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8
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Packing
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Graphite Ribbon Rings (Backup seal)
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9
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Bonnet Bolting
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ASTM A193 B8 / A194 8 (Stainless Steel)
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10
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Handwheel
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Ductile Iron / Fabricated Steel
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- Dimensional Data (1.5″ – Class 300 LB)
Note: The extended bonnet length (H) is critical for cryogenic service to maintain the packing box temperature above 0°C.
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Dimension
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Value (mm / inches)
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Standard / Reference
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Face-to-Face Length (L)
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368 mm (14.50 inches)
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ASME B16.10
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Extended Bonnet Height (H)
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Approx. 580 – 620 mm
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Required to keep stem seal above freezing point (BS 6364 requirement)
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Flange Diameter (D)
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190 mm (7.48 inches)
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ASME B16.5 (Class 300)
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Bolt Circle Diameter (K)
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152.4 mm (6.00 inches)
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ASME B16.5 (Class 300)
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Number of Bolt Holes
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8
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ASME B16.5 (Class 300)
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Bolt Hole Diameter
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22 mm (0.88 inches)
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For 3/4″ bolts
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Weight
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Approx. 30 – 40 kg
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Dependent on bonnet extension length
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- Special Requirements for Cryogenic Service (Per BS 6364)
6.1 Deep Cryogenic Treatment
All stainless steel pressure parts shall be thermally cycled to -196°C to stabilize the austenitic structure and prevent dimensional changes during operation .
6.2 Extended Bonnet (Cold Box Design)
The bonnet length must be sufficient to ensure the temperature at the stuffing box is maintained above 0°C to prevent ice formation on the stem and bellows .
6.3 Stellite Hardfacing
Seat and wedge surfaces must be overlaid with Stellite (Cobalt-Chromium alloy) to prevent galling and seizure at cryogenic temperatures .
6.4 Cleanliness & Degreasing
Valves for oxygen service (LO₂) require oxygen cleaning to remove all hydrocarbons and prevent combustion risks.
- Inspection & Testing Procedure (Per BS 6364)
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Test Type
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Procedure
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Acceptance Criteria
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Shell Test
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Hydrostatic test at 1.5 x rated pressure (77 bar) .
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No visible leakage through pressure boundary
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Seat Test (Ambient)
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Hydrostatic test at 1.1 x rated pressure (56 bar) .
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No visible leakage across seat
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Cryogenic Test
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Test at -196°C per BS 6364 Clause 8
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Valve must operate without seizure; leakage rate ≤ 100 mm³/s (per nominal size)
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Bellows Integrity
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Helium leak test
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Leak rate ≤ 1×10⁻⁶ mbar·L/s
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Operational Torque
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Measure at ambient and cryogenic temp
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Torque must be within design limits
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- Features & Benefits
- Zero Fugitive Emissions: Welded metal bellows eliminates stem leakage, critical for volatile cryogenic fluids.
- BS 6364 Certified: Full compliance with international cryogenic valve standard .
- No Icing: Extended bonnet prevents ice formation on stem seals .
- Long Cycle Life: Bellows design handles thermal cycling without failure.
- Stellite Protection: Prevents galling of stainless steel at cryogenic temperatures .
GARANTIE :
SAVVY VALVES s'engage à fournir des produits d'une qualité exceptionnelle et un service après-vente sans souci. Nos vannes sont garanties pour une durée de vie minimale de 12 mois, période durant laquelle nous fournissons gratuitement toutes les pièces de rechange nécessaires et des instructions d'entretien détaillées. Pendant la période de garantie, en cas de dommage non causé par l'homme, nous remplaçons gratuitement les composants et fournissons une assistance technique professionnelle. Après l'expiration de la garantie, seuls les pièces de rechange sont à votre charge, tout en bénéficiant de services de maintenance à prix réduits. Notre objectif est d'aider nos clients à réduire leurs coûts d'exploitation et à optimiser leur production grâce à une qualité fiable et un service après-vente complet. Qu'il s'agisse de questions techniques ou de besoins de maintenance, notre équipe d'experts répondra rapidement pour garantir le fonctionnement optimal de votre système de vannes.