ASME B16.20 — Sealing element outside diameter (mm)
ASME B16.20 Sealing element outside diameter (mm) — 19 sizes.
| NPS | DN | Class 150–600 (mm) | Class 900–2500 (mm) |
|---|---|---|---|
| ½" | 15 | 31.8 | 31.8 |
| ¾" | 20 | 39.6 | 39.6 |
| 1" | 25 | 47.8 | 47.8 |
| 1¼" | 32 | 60.5 | 60.5 |
| 1½" | 40 | 69.9 | 69.9 |
| 2" | 50 | 85.9 | 85.9 |
| 2½" | 65 | 98.6 | 98.6 |
| 3" | 80 | 120.7 | 120.7 |
| 4" | 100 | 149.4 | 149.4 |
| 5" | 125 | 177.8 | 177.8 |
| 6" | 150 | 209.6 | 209.6 |
| 8" | 200 | 263.7 | 257.3 |
| 10" | 250 | 317.5 | 311.2 |
| 12" | 300 | 374.7 | 368.3 |
| 14" | 350 | 406.4 | 400.1 |
| 16" | 400 | 463.6 | 457.2 |
| 18" | 450 | 527.1 | 520.7 |
| 20" | 500 | 577.9 | 571.5 |
| 24" | 600 | 685.8 | 679.5 |
- Dimensions are in millimetres unless stated otherwise.
- For Class 900, NPS ½" to 2½", the Class 1500 gasket is used.
- Class 2500 is listed to NPS 12" only.
- Inner ring inside diameters have been revised between editions of ASME B16.20 and are not tabulated here; ask for the value to the edition your project specifies.
- Nominal sealing element thickness is 4.5 mm (0.175").