Spiral wound gasket ½" Class 1500 — ASME B16.20
Spiral wound gasket ½" Class 1500 to ASME B16.20: inner ring id 14.2 mm, sealing element id 19.1 mm, sealing element od 31.8 mm, centering ring od 63.5 mm.
Dimensions of Spiral wound gasket ½" Class 1500
| Symbol | Dimension | Value |
|---|---|---|
| d1 | Inner ring ID | 14.2 mm (0.559 in) |
| d2 | Sealing element ID | 19.1 mm (0.752 in) |
| d3 | Sealing element OD | 31.8 mm (1.252 in) |
| d4 | Centering ring OD | 63.5 mm (2.500 in) |
SKU TSH-GASKET-ASME-B16-20-CLASS-1500-12 · Standard ASME B16.20 · verified by 2+ sources
Purchase description
SPIRAL WOUND GASKET, ½", CLASS 1500, SS316 + GRAPHITE, CS RINGS, ASME B16.20
Available materials: SS316 + graphite, CS rings, SS316 + PTFE, CNAF (non-asbestos), Neoprene / EPDM rubber, Soft iron / SS316 (ring joint).
Notes
- NPS 3–20: HGFF, Piping-World and SJ Senersol agree. NPS 1/2, 2, 24: Piping-World + Wermac. NPS 3/4, 2-1/2: Piping-World (3/4 also SJ Senersol). NPS 1: HGFF.
- NPS 1-1/4 and 1-1/2: only inner ring ID confirmed (Piping-World/Wermac 33.3, 41.4); other cells not recovered. Global Supply Line PDF gives 38.1/44.5 (Class 150-style) — rejected.
- An SJ Senersol row giving NPS 1 d4 85.9 mm is the Class 2500 value; rejected.
- Thickness: inner/centering ring 2.97–3.33 mm, sealing element 4.45 mm (Wermac). For RF flanges to ASME B16.5.
Same size, other ratings
Other sizes — Spiral wound gasket, Class 1500
Frequently asked questions
What are the main types of pipe flanges?
Weld neck (WN), slip-on (SO), blind (BL), socket weld (SW), threaded (THD), lap joint (LJ) and plate flanges. Special types include orifice, long weld neck, reducing flanges and spectacle blinds.
When should I use a weld neck flange instead of a slip-on?
Use weld neck flanges for high pressure, high or cycling temperature, and lines with vibration or fatigue loading. The tapered hub and full-penetration butt weld spread stress smoothly. Slip-on flanges are cheaper and easier to align, but their fatigue life is roughly one third of a WN.
What does Class 150, 300 or 600 mean on a flange?
The ASME class is a pressure-rating designation, not a pressure in psi. The allowable pressure depends on the material group and temperature. A Class 150 A105 flange is rated 19.6 bar at 38 °C but 13.8 bar at 200 °C.
Is a 150# flange rated for 150 psi?
No. A Class 150 carbon-steel flange is rated about 285 psi (19.6 bar) at ambient temperature, and about 170 psi (11.7 bar) at 260 °C. The "150" is a class number.