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 | Parâmetro |
Tamanho nominal | 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 |
- Padrões de Design
Item | Padrão |
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) | Observações |
Corpo | 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 |
Tronco | 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 | Parâmetro |
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.
GARANTIA:
A SAVVY VALVES está comprometida em oferecer produtos de qualidade excepcional e um serviço pós-venda sem preocupações. Nossas válvulas têm garantia de vida útil mínima de 12 meses, durante a qual forneceremos gratuitamente todas as peças de reposição necessárias e instruções detalhadas de manutenção. Dentro do período de garantia, caso ocorra algum dano não causado por intervenção humana, substituiremos os componentes gratuitamente e forneceremos suporte técnico profissional. Após o término da garantia, os clientes pagam apenas o custo das peças de reposição, continuando a se beneficiar de serviços de manutenção com desconto. Nosso objetivo é ajudar os clientes a reduzir custos operacionais e aumentar a eficiência da produção por meio de qualidade confiável e suporte pós-venda abrangente. Seja para consultas técnicas ou necessidades de manutenção, nossa equipe de especialistas responderá prontamente para garantir que seu sistema de válvulas mantenha o desempenho ideal o tempo todo.