Spirax Sarco Bellows Sealed Globe Valves: Zero-Leakage Industrial Fluid Control Solutions
Product Overview
Spirax Sarco bellows sealed globe valves represent an innovative solution for on/off valve applications. The unique bellows seal design fundamentally eliminates stem leakage, fully complying with stringent global sealing standards. These products not only ensure plant safety and energy savings but also maintain a clean working environment, widely applied in various industrial fluid system control requirements.
The products feature ergonomically designed handwheels with robust non-rising handwheel fittings and lock nuts. The lock nut on the bonnet can fix the valve opening at a specific position, ensuring operational stability. All series products are equipped with open/close position indicators for convenient on-site operation and status monitoring.
Core Product Features
Zero-Leakage Sealing Performance
Utilizing titanium-reinforced stainless steel dual/triple-layer bellows construction, the bellows are completely isolated from the fluid without direct contact, achieving 100% sealing effectiveness. Even under extreme conditions, the packing seal on the stem serves as secondary protection against leakage. The bellows fatigue life complies with the latest international standards, ensuring long-term reliable operation.
Maintenance-Free and Long-Life Design
The bellows seal structure not only eliminates traditional valve leakage concerns but also achieves maintenance-free operation. The products do not experience structural failures during operation, internal component replacement is quick and simple, and all gaskets are asbestos-free, meeting environmental requirements. Additionally, the products are unaffected by vibration and can adapt to a wide range of pressure and temperature operating conditions, with service life significantly exceeding traditional globe valves.
Multi-Scenario Adaptability
Available with throttling plugs, soft-seated plugs, balanced plugs and various other plug options. The throttling plug can replace traditional flat plugs for rough control of system pressure and flow, and can also serve as bypass valves. Full stainless steel models are specifically designed for corrosive environments. The bonnet features a grease nipple for periodic lubrication of the stem and spindle, extending the product's application boundaries.
Model Classification and Technical Parameters
Main Model Series
| Model Series | Body Material | Applicable Standards | Core Features |
|---|---|---|---|
| BSA2T | Ductile Iron | PN16/PN25 | Basic design, widely suitable for general conditions |
| BSA3T | Cast Steel | PN25/PN40/ANSI150/300 | Medium-high pressure adaptation, metal seat rated to 425°C |
| BSA6T | Stainless Steel | PN40 | Corrosive environment specific, full stainless steel construction |
| BSA3HP | Carbon Steel | PN100/Class600 | High pressure design, maximum allowable pressure 102.1 barg |
| BSA2-BD/BSA3-BD | Ductile Iron/Cast Steel | Custom Standards | Special condition customized models |
Key Technical Parameters Summary
| Technical Specification | Value Range |
|---|---|
| Size Range | DN15 - DN400 |
| Pressure Rating | PN16 - PN100, ANSI150 - 600, JIS/KS20K |
| Maximum Allowable Temperature | 425°C (metal seat), 230°C (R-PTFE soft seat) |
| Minimum Allowable Temperature | -29°C (select models), -10°C (standard models) |
| Maximum Allowable Pressure | 102.1 barg @ 50°C (BSA3HP Class600) |
| Connection Type | Flanged (EN1092/ISO7005, ASME B16.5) |
| Plug Material | Stainless Steel, R-PTFE soft seat, Stellite alloy |
| Bellows Material | Stainless Steel (1.4571/1.4301/1.4307, etc.) |
Typical Model Limitations (BSA3T ANSI Series)
| Design Condition | ANSI150 | ANSI300 | JIS/KS20K |
|---|---|---|---|
| Maximum Allowable Pressure (PMA) | 9 barg @ 50°C | 51 barg @ 38°C | 34 barg @ 140°C |
| Maximum Allowable Temperature (TMA) | 425°C | 425°C | 425°C |
| Maximum Operating Pressure Saturated Steam (PMO) | 14 barg | 41.6 barg | 30.7 barg |
| Minimum Operating Temperature | -29°C | -29°C | -29°C |
| Cold Hydrostatic Test Pressure | 31 barg | 77 barg | 50 barg |
Material Selection Specifications
Product component materials are rigorously selected to ensure reliability and corrosion resistance under corresponding conditions. Main component materials are as follows:
| Component | Material Specification | Standard |
|---|---|---|
| Body/Bonnet | Carbon Steel (1.0619+N/SA-216 WCB), Ductile Iron (GGG40.3), Stainless Steel (1.4408/CF8M) | EN10213, ASTM A216, DIN1693 |
| Bellows Assembly | Stainless Steel (1.4571/1.4301/1.4541/X6 Cr Ni Ti 1810) | DIN17440, ASTM A276 |
| Stem | Stainless Steel (AISI 420, 1.4571) | ASTM A276 |
| Fasteners | Alloy Steel (ASTM A193 B7), Stainless Steel (A4-70) | ASTM, DIN |
| Internal Seals | Graphite/Stainless Steel, R-PTFE | Industrial Standards |
| Handwheel | Pressed Steel (BS1449 CR4), Carbon Steel, Cast Iron | BS1449 |
Application Scenarios and Suitable Media
Main Application Areas
- Steam and Condensate Systems: Suitable for industrial steam transmission, condensate recovery and other conditions, providing reliable on/off control and throttling adjustment
- Process Fluid Systems: Adaptable to various industrial production media transport, including thermal fluids, oils and other viscous fluids
- Hot and Cold Fluid Systems: Applicable to hot water supply, cold water circulation and other wide temperature range conditions
- Gas Systems: Suitable for compressed air, industrial gases and other dry or corrosive gas control
- Bypass and Balance Systems: Used as balance line valves, bypass valves for system pressure balance adjustment
Suitable Media Types
- Steam (saturated steam, superheated steam)
- Industrial Gases (compressed air, nitrogen, oxygen, etc.)
- Liquid Media (hot water, cold water, thermal oil, lubricating oil, industrial wastewater, etc.)
- Corrosive Media (stainless steel models required)
Important Usage Notes
Selection Recommendations
Select appropriate models based on operating pressure, temperature and media characteristics: For corrosive media, prioritize BSA6T stainless steel series; For high pressure conditions (above PN40), BSA3T or BSA3HP series are recommended; For low temperature conditions (below -10°C), confirm that the model's minimum allowable temperature meets requirements.
Installation Precautions
Ensure flange connections comply with corresponding standards (EN1092 or ASME B16.5) during valve installation to avoid leakage due to improper connections; Installation direction must follow media flow direction markings to ensure proper plug operation; Regularly check handwheel lock nut condition to prevent valve opening deviation.
Prohibited Usage Scenarios
Products must not be used in conditions exceeding their pressure-temperature range; R-PTFE soft seat models are prohibited for use above 230°C; Models without specified corrosion resistance ratings are prohibited for strongly corrosive media; Prolonged overpressure conditions with the valve in closed position are prohibited.
Note: Products fully comply with the European Pressure Equipment Directive. All model bellows fatigue life has been certified to international standards. Users can select plug types and connection methods according to specific operating requirements.
