Bellows Seal Gate Valve for Cryogenic Service – ASTM A182 F304L
Description
Bellows Seal Cryogenic Gate Valve – ASTM A182 F304L
Model: BSGV-CR-F304L
Product Description: Bellows-sealed, extended bonnet gate valve with outside screw and yoke (OS&Y), specifically designed for cryogenic service. Manufactured from ASTM A182 F304L stainless steel to ensure excellent low-temperature toughness and corrosion resistance.
1. Main Design Codes and Standards
| Item | Standard / Code |
|---|---|
| Valve Design | ASME B16.34, API 602, BS 6364 |
| End Connections | ASME B16.5 (Flanged) / ASME B16.25 (Butt Weld) / ASME B16.11 (Socket Weld) |
| Face-to-Face | ASME B16.10 / API 602 (extended for cryogenic bonnet) |
| Cryogenic Testing | ISO 28921-1, BS 6364 |
| Testing & Inspection | API 598, ISO 5208 (with cryogenic leakage test) |
| Fugitive Emissions | ISO 15848-1 (optional) |
| Bonnet Type | Extended, cold-insulating bonnet (gas column design) |
2. Main Technical Parameters
| Parameter | Specification |
|---|---|
| Available Size Range | 1/2″ (DN15) to 6″ (DN150) – Typical data given for 2″ |
| Pressure Class | Class 150, 300, 600 |
| End Connections | Flanged RF, Butt Weld BW, Socket Weld SW (as requested) |
| Configuration | Extended bonnet, OS&Y, rising stem |
| Sealing System | Multi-ply bellows seal + auxiliary PTFE/graphite packing |
| Flow Direction | Bi-directional |
| Minimum Design Temperature | -196 °C (-321 °F) |
3. Pressure-Temperature Ratings (per ASME B16.34, Material Group 2.1 – A182 F304L)
Ratings valid down to -196 °C without derating, thanks to stable austenitic structure.
| Temperature | Class 150 Max. WP | Class 300 Max. WP | Class 600 Max. WP |
|---|---|---|---|
| -196 to 38 °C | 19.8 bar (285 psi) | 51.1 bar (740 psi) | 102.2 bar (1480 psi) |
| 50 °C | 18.4 bar (265 psi) | 47.8 bar (690 psi) | 95.7 bar (1380 psi) |
| 100 °C | 13.8 bar (200 psi) | 40.0 bar (580 psi) | 80.0 bar (1160 psi) |
| 150 °C | 10.3 bar (150 psi) | 34.5 bar (500 psi) | 68.9 bar (1000 psi) |
| 200 °C | 8.6 bar (125 psi) | 30.0 bar (435 psi) | 60.0 bar (870 psi) |
WP = Working Pressure. For intermediate temperatures, linear interpolation is permitted.
4. Materials of Main Parts
| No. | Part Name | Material | Remarks |
|---|---|---|---|
| 1 | Body | ASTM A182 F304L | 304L forgings, fully solution annealed |
| 2 | Bonnet (Extended) | ASTM A182 F304L | Gas column extension to protect packing |
| 3 | Wedge (Disc) | ASTM A182 F304L | Seating faces hardfaced with Stellite Gr.6 or solid Stellite |
| 4 | Seat Rings | ASTM A182 F304L + Stellite Gr.6 overlay | Renewable or integral seats |
| 5 | Stem | ASTM A182 F304L | Ground and polished, low-friction surface |
| 6 | Bellows Assembly | Inconel 625 (UNS N06625) / AISI 316L | Multi-ply hydroformed, full penetration weld |
| 7 | Packing | PTFE / Flexible Graphite with PTFE impregnation | Low-temperature formulation, live-loaded available |
| 8 | Bonnet Gasket | PTFE / Spiral Wound SS316L-Graphite | Cryogenic compatible |
| 9 | Gland / Gland Flange | ASTM A276 316L | |
| 10 | Yoke | ASTM A182 F304L / ASTM A240 304L | |
| 11 | Handwheel | Ductile Iron / SS304 | |
| 12 | Bolting | ASTM A193 B8M / A194 Gr.8M | SS316L fasteners for corrosion resistance |
Note: The extended bonnet length ensures the packing zone stays above 0 °C (32 °F) under rated cryogenic conditions.
5. Dimensions & Weight – Typical Example (2” Class 300, Flanged Extended Bonnet)
| Parameter | Dimension (mm) | Remarks |
|---|---|---|
| Face-to-Face Length (L) | 295 (per ASME B16.10, long pattern) | For cryogenic service |
| Extended Bonnet Height (H1) | ≥250 | Length verified by thermal calculation |
| Center to Handwheel Top (H) | ~650 | Fully open |
| Handwheel Diameter (D) | ~200 | |
| Flange Size / Rating | 2” ASME B16.5 Class 300 RF | |
| Approx. Weight | 48 kg | May vary with configuration |
Refer to certified drawings for exact dimensions of other sizes and pressure classes.
6. Performance Testing (Cryogenic Service)
| Test Item | Test Medium | Test Pressure | Acceptance Criteria |
|---|---|---|---|
| Shell Strength | Water (ambient) | 1.5 × CWP | No visible leakage |
| Seat Tightness (ambient) | Air / Water | 1.1 × CWP | API 598 rate |
| Cryogenic Seat Test | Liquid Nitrogen (-196 °C) | 1.1 × CWP or rated ΔP | BS 6364 / ISO 28921-1 leakage rate |
| Bellows Pneumatic Test | Dry Nitrogen | 0.6 MPa | Zero bubble leakage |
| Bellows Life Cycle | – | ≥10,000 cycles at ambient & cryo | Mechanically intact, sealing tight |
CWP = Cold Working Pressure (rated pressure at 38 °C).
7. Bellows & Sealing Characteristics
-
Bellows Design: Multi-ply (2–3 plies) hydroformed bellows, full penetration welded to stem and bonnet.
-
Cryogenic Adaptability: Bellows material (Inconel 625/316L) retains ductility at -196 °C. No brittle fracture risk.
-
Secondary Back-Up: PTFE/graphite stuffing box acts as a safety seal and gives visual warning in the unlikely event of bellows failure.
-
Bonnet Design: Extended bonnet with integral cold box provides a warm stem-packing interface, preventing ice formation and packing seizure.
8. Application Scope
-
Suitable Media: Liquefied natural gas (LNG), liquid nitrogen (LIN), liquid oxygen (LOX) – cleaned for oxygen service upon request, liquid argon, liquid ethylene, and other cryogenic fluids.
-
Temperature Range: -196 °C to +200 °C (continuous).
-
Key Features:
-
Zero external leakage from bellows, critical for hazardous or high-purity cryogens.
-
F304L material provides superior impact toughness down to liquid nitrogen temperatures.
-
Extended bonnet eliminates packing freeze-up and ensures reliable operation.
-
Smooth, crevice-free internal geometry minimizes fluid accumulation and allows easy purge.
-
9. Optional Configurations & Accessories
-
Clean & Degreased for Oxygen Service: Compliant with CGA G-4.1 or ASTM G93.
-
Live-Loaded Packing: Belleville spring washers maintain constant packing load through thermal cycles.
-
Locking Device: Handwheel lock in open or closed position.
-
Actuator Mounting: ISO 5211 base for pneumatic or electric actuators (with thermal coupling).
-
Sensors: Proximity switches, position indicators.
-
Cryogenic Insulation Box: Pre-formed cold box with vapor barrier.
Disclaimer: This technical data sheet is intended as an engineering reference based on common industrial practice and applicable standards. Specific product data may vary and should be verified against the manufacturer’s certified documentation and drawings prior to procurement or installation.
