Technical Data Sheet
Product: Bellows Seal Gate Valve
Model / Size: 3/4″ – 800LB – SW
- Product Description
This valve adopts a bellows seal design, which fundamentally eliminates stem packing leakage commonly found in conventional gate valves. The bellows assembly, combined with the stem, forms a static seal. An additional packing box serves as a secondary backup seal, achieving a “zero leakage” stem sealing performance. It is suitable for severe service conditions including high temperature, high pressure, high vacuum, and toxic, flammable, or corrosive media.
- Basic Parameters
Item | Paramètre |
Taille nominale | 3/4 inch (DN 20) |
Pressure Class | Class 800LB (equivalent to PN 140 ~ 160 bar, depending on standard) |
End Connection | Socket Weld (SW) |
Structure Type | Outside Screw & Yoke (OS&Y) / Solid Wedge |
Stem Sealing | Bellows seal + auxiliary graphite packing |
- Normes de conception
Item | Standard |
Design & Manufacture | API 602 (Steel Gate, Globe and Check Valves for Petroleum and Natural Gas Industries – Compact Design) |
Pressure-Temperature Rating | ASME B16.34 |
End Connection (SW) | ASME B16.11 |
Face-to-Face Dimension | ASME B16.10 / Manufacturer’s standard |
Inspection & Testing | API 598 (or ISO 5208) |
Bellows Testing | ISO 15848-1 (Fugitive Emissions Standard) |
- Bill of Materials (Typical Configuration)
Part Name | Material (Typical Options) | Remarques |
Corps | A105 / A182 F316 | Carbon steel / Stainless steel optional |
Wedge | A105 + 13Cr / F316 | 13Cr or Stellite hardfacing on sealing faces |
Seat Ring | Integral per API 602 | Stellite 6 hardfacing on body seat |
Tige | A182 F6a / F316 | Precipitation hardened stainless / Austenitic SS |
Bellows Assembly | SS304 / SS316L | Multi-ply formed, high cycle life |
Bonnet | A105 / A182 F316 | Matching body material |
Packing | Flexible Graphite | With corrosion inhibitor |
Handwheel / Stem Nut | Carbon steel (or ductile iron) / Copper alloy | |
- Dimensions & Weight (Reference)
Item | Value |
Face-to-Face (L) | Approx. 117 mm (per API 602) |
Handwheel Diameter (W) | Approx. 100 mm |
Overall Height (H) | Approx. 240 mm |
Socket Weld Bore (D) | Per ASME B16.11, socket depth approx. 10 mm |
Approx. Weight | 5.5 ~ 7.5 kg (depending on material) |
- Operating Conditions
Item | Paramètre |
Suitable Media | Steam, thermal oil, toxic gases/liquids, corrosive media, hydrocarbons |
Temperature Range (Carbon Steel) | -29°C ~ 425°C |
Temperature Range (Stainless Steel) | -196°C ~ 538°C (cryogenic / high temperature) |
Max. Allowable Pressure | Per ASME B16.34, Class 800LB at ambient temperature (38°C) approx. 13.8 MPa (138 bar) |
- Testing & Inspection
- Shell Strength Test: 1.5 times rated pressure, no leakage.
- High-Pressure Seat Test: 1.1 times rated pressure.
- Low-Pressure Pneumatic Test: 0.6 MPa compressed air.
- Bellows Leak Test: Helium mass spectrometry, leakage rate < 1×10⁻⁶ Pa·m³/s (or meeting Class V sealing requirement).
- Operational Test: Valve cycled fully open/close under rated differential pressure.
- Features & Benefits
- Zero Leakage Assurance: The bellows isolates the stem from the atmosphere, eliminating external stem leakage – ideal for stringent environmental applications.
- Long Service Life: High-cycle-life bellows design ensures reliability under frequent operation.
- Low Maintenance: Dual stem sealing (bellows + packing) provides a secondary seal in the event of bellows failure, ensuring system safety.
- High Temperature & Pressure Capability: Class 800 rating with socket weld ends is suitable for high-pressure steam and thermal oil systems.
Notes:
- Dimensions and weights are typical values based on API 602; actual values may vary slightly depending on manufacturer design (e.g., handwheel size, bonnet height).
- For NACE MR0175 (sour service) compliance, please specify when ordering.
- During installation, follow the approved Welding Procedure Specification (WPS) for socket weld connections to avoid welding stress that could affect bellows life.
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.