ASME B16.5 Spiral Wound Gaskets – Specifications & Dimensions
Spiral wound gaskets are commonly used with ASME B16.5 flanges and are designed to provide a reliable seal in high-pressure and high-temperature applications. Below are the key details regarding their specifications, dimensions, and materials.
1. Spiral Wound Gasket Standards & Compliance
ASME B16.20: Covers metallic and semi-metallic gaskets for pipe flanges, including spiral wound gaskets.
ASME B16.5: Specifies flange dimensions where these gaskets are used.
API 601: Standard for metallic gaskets in refinery applications.
2. Spiral Wound Gasket Construction
| Component | Material Options |
|---|---|
| Outer Ring | Carbon steel (CS), Stainless steel (SS 304/316) |
| Inner Ring | Optional (SS 304/316, CS) |
| Filler Material | Graphite, PTFE, Mica |
| Winding Metal | SS 304, SS 316, Inconel, Monel |
3. ASME B16.5 Spiral Wound Gasket Dimensions
Spiral wound gaskets for ASME B16.5 flanges come in two styles:
Style R (Raised Face) – For raised face (RF) flanges.
Style F (Flat Face) – For flat face (FF) flanges.
Standard Dimensions (Partial Chart – Class 150 to 2500)
| NPS | Class | Inner Diameter (ID) | Outer Diameter (OD) | Thickness |
|---|---|---|---|---|
| ½" | 150 | 0.62" (15.7 mm) | 3.50" (88.9 mm) | 0.175" (4.45 mm) |
| 2" | 300 | 2.12" (53.8 mm) | 6.00" (152.4 mm) | 0.175" (4.45 mm) |
| 4" | 600 | 4.25" (108 mm) | 9.00" (228.6 mm) | 0.175" (4.45 mm) |
| 8" | 900 | 8.25" (209.6 mm) | 13.75" (349.3 mm) | 0.175" (4.45 mm) |
| 12" | 1500 | 12.25" (311.2 mm) | 19.00" (482.6 mm) | 0.175" (4.45 mm) |
(For full dimensions, refer to ASME B16.20 Table 2)
4. Pressure-Temperature Ratings
Spiral wound gaskets must match the flange's pressure-temperature rating (per ASME B16.5).
| Class | Max Pressure (psi @ 100°F) | Common Applications |
|---|---|---|
| 150 | 285 psi | Low-pressure steam, water |
| 300 | 740 psi | Process piping |
| 600 | 1,480 psi | High-pressure steam |
| 900 | 2,220 psi | Petrochemical |
| 1500 | 3,705 psi | Power plants |
| 2500 | 6,170 psi | High-pressure gas |
5. Installation & Torque Recommendations
Bolt Torque: Follow ASME PCC-1 guidelines based on bolt material and gasket type.
Alignment: Ensure flange faces are clean and parallel.
Compression: Avoid over-tightening to prevent gasket crushing.
6. Common Spiral Wound Gasket Types
| Type | Filler Material | Max Temp (°F) | Applications |
|---|---|---|---|
| SS304 + Graphite | Graphite | 850°F (454°C) | Steam, oil, gas |
| SS316 + PTFE | PTFE | 450°F (232°C) | Corrosive chemicals |
| Inconel + Mica | Mica | 1,500°F (816°C) | High-temperature |
Key Takeaways
✔ ASME B16.20 defines dimensions for spiral wound gaskets.
✔ Material selection depends on temperature, pressure, and fluid compatibility.
✔ Proper installation (torque, alignment) is critical for leak-free performance.
For a full dimension table, refer to ASME B16.20 or manufacturer catalogs. Let me know if you need details for a specific size or class!
