Bellows Seal F91 Gate Valve-2″ 1500LB SW
Description
Bellows Seal F91 Gate Valve – 2″ 1500LB SW Technical Data Sheet
Model: BSGV-F91-2″-1500-SW
Product Description: Bellows sealed F91 alloy steel gate valve, outside screw and yoke (OS&Y) design, 2-inch, Class 1500, socket weld ends.
1. Main Design Codes and Standards
| Item | Standard / Code |
|---|---|
| Valve Design | ASME B16.34, API 602 |
| End Connections | ASME B16.11 (Socket Weld) |
| Pressure-Temperature Ratings | ASME B16.34, Class 1500, Material Group 2 |
| Face-to-Face Dimensions | API 602 / Manufacturer’s Standard |
| Testing & Inspection | API 598, ISO 5208 |
| Fugitive Emission (optional) | ISO 15848-1 |
| Bonnet Type | Bolted Bonnet / Pressure Seal (as per design) |
2. Main Technical Parameters
| Parameter | Specification |
|---|---|
| Nominal Size | 2″ (DN50) |
| Pressure Class | Class 1500 (PN260) |
| End Connection | Socket Weld (SW), for Schedule 160 pipe |
| Configuration | Bolted Bonnet, OS&Y, Rising Stem |
| Sealing System | Bellows Seal + Auxiliary Packing |
| Operation | Handwheel (Gear operator optional) |
| Flow Direction | Bi-directional (gate valve design) |
3. Pressure-Temperature Ratings (per ASME B16.34 Group 2)
| Temperature (°C) | Max. Working Pressure (MPa) | Approx. psi |
|---|---|---|
| -29 to 38 | 25.9 | 3755 |
| 200 | 25.9 | 3755 |
| 400 | 24.1 | 3505 |
| 454 | 23.1 | 3345 |
| 482 | 21.7 | 3150 |
| 510 | 20.2 | 2925 |
| 538 | 18.6 | 2695 |
| 566 | 16.9 | 2455 |
| 593 | 15.1 | 2185 |
| 621 | 11.9 | 1725 |
| 649 | 8.9 | 1290 |
Note: The values listed are allowable working pressures at standard temperature points. Linear interpolation is permitted for intermediate temperatures. Allow appropriate system design margin in practice.
4. Materials of Main Parts
| No. | Part Name | Material | Remarks |
|---|---|---|---|
| 1 | Body / Bonnet | ASTM A182 F91 | 9Cr-1Mo-V forged steel, high-temp service |
| 2 | Wedge (Disc) | ASTM A182 F91 | Seating faces hardfaced with Stellite Gr.6 |
| 3 | Seat Rings | Integral hardfaced Stellite Gr.6 | Hard alloy seating surface |
| 4 | Stem | ASTM A182 F91 | Quenched & tempered, nitrided surface |
| 5 | Bellows Assembly | Inconel 625 (UNS N06625) | Multi-ply hydroformed, full penetration weld |
| 6 | Packing | Flexible Graphite with Nickel Wire Reinforcement | High-temperature, low emission |
| 7 | Bonnet Gasket | SS304 / Graphite Spiral Wound | With inner & outer rings |
| 8 | Gland / Gland Flange | ASTM A276 Grade 410 | Hardened |
| 9 | Yoke | ASTM A216 WCB / A182 F91 | Carbon steel or alloy steel per conditions |
| 10 | Handwheel | Ductile Iron / Carbon Steel | Malleable iron also acceptable |
| 11 | Bolting | ASTM A193 B16 / A194 Gr.4 | High-temperature alloy steel studs & nuts |
5. Dimensions and Weight (Typical)
| Parameter | Dimension (mm) | Remarks |
|---|---|---|
| Face-to-Face Length (L) | 292 | Per API 602 |
| Height to Top (H) Full Open | ~570 | Including handwheel |
| Handwheel Diameter (D) | ~250 | – |
| Socket Weld Bore Dia. | 61.2 (min.) | For 2″ Sch.160 pipe |
| Socket Depth | ≥15.9 | Per ASME B16.11 |
| Approx. Net Weight | 45 kg | May vary slightly by configuration |
Note: Dimensions are typical design values. Refer to certified manufacturer drawings for final data.
6. Performance Testing
| Test Item | Test Medium | Test Pressure | Acceptance Criteria |
|---|---|---|---|
| Shell Strength | Water | 38.9 MPa (1.5 × rated) | No visible leakage or structural damage |
| Seat Tightness | Water / Air | 28.5 MPa (1.1 × rated) | Leakage rate per API 598 |
| Bellows Assembly (Pneumatic) | Dry Air / Nitrogen | 0.6 MPa | Zero visible bubble leakage |
| Bellows Life Cycle Test | – | ≥10,000 cycles | Mechanically intact, no leakage |
7. Bellows Characteristics
-
Bellows Type: Multi-ply, multi-convolution, hydroformed; no stagnation zone.
-
Connection: Stem-to-bellows fully seal-welded; bellows lower end seal-welded to bonnet.
-
Design Life: ≥10,000 full-stroke cycles.
-
Secondary Seal: Upper stuffing box packed with flexible graphite. Even in case of unexpected bellows failure, the packing provides short-term sealing and indicates service requirement.
8. Application Scope
-
Suitable Media: High-temperature steam, boiler feedwater, heat transfer oil, hydrocarbons, and high-temperature/high-pressure process fluids.
-
Temperature Range: -29 °C to 610 °C (continuous); up to 649 °C (intermittent).
-
Key Features:
-
Dual sealing design (bellows zero-external-leak + auxiliary packing safety seal).
-
Excellent high-temperature strength and creep resistance of F91 material, ideal for power plant steam lines.
-
Socket weld connection provides robust, leak-tight joint for small-bore high-pressure piping.
-
9. Optional Configurations & Accessories
-
Bevel gear operator (for remote or reduced-torque operation)
-
Position indicator
-
Limit switches
-
High-temperature insulation jacket
-
Actuator mounting interface per ISO 5211 (pneumatic / electric actuator adaptation)
Disclaimer: This technical data sheet is compiled based on general industry standards and typical design parameters for engineering reference and valve selection purposes. Exact product data shall be confirmed against the manufacturer’s official documentation and certified drawings.







