Gasket dimensions for flat ring and full face applications
ASME B16.21 class 400
| Nominal bore | Flat ring and full face gasket | Flat ring gasket | Full face gasket | Nominal bore | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Inner diameter | Outer diameter | Outer diameter | Bolt circle diameter | Diameter of holes | Number of bolt holes | |||||||
| Inches | mm | Inches | mm | Inches | mm | Inches | mm | Inches | mm | |||
| 1/2 | 27/32 | 21.4 | 2.12 | 53.8 | 3.75 | 95.3 | 2.62 | 66.5 | 0.62 | 15.7 | 4 | 1/2 |
| 3/4 | 1 1/16 | 27.0 | 2.62 | 66.5 | 4.62 | 117.3 | 3.25 | 82.6 | 0.75 | 19.1 | 4 | 3/4 |
| 1 | 1 5/16 | 33.3 | 2.88 | 73.2 | 4.88 | 124.0 | 3.50 | 88.9 | 0.75 | 19.1 | 4 | 1 |
| 1 1/4 | 1 21/32 | 42.1 | 3.25 | 82.6 | 5.25 | 133.4 | 3.88 | 98.6 | 0.75 | 19.1 | 4 | 1 1/4 |
| 1 1/2 | 1 29/32 | 48.4 | 3.75 | 95.3 | 6.12 | 155.4 | 4.50 | 114.3 | 0.88 | 22.4 | 4 | 1 1/2 |
| 2 | 2 3/8 | 60.3 | 4.38 | 111.3 | 6.50 | 165.1 | 5.00 | 127.0 | 0.75 | 19.1 | 8 | 2 |
| 2 1/2 | 2 7/8 | 73.0 | 5.12 | 130.0 | 7.50 | 190.5 | 5.88 | 149.4 | 0.88 | 22.4 | 8 | 2 1/2 |
| 3 | 3 1/2 | 88.9 | 5.88 | 149.4 | 8.25 | 209.6 | 6.62 | 168.1 | 0.88 | 22.4 | 8 | 3 |
| 3 1/2 | 4 | 101.6 | 6.38 | 162.1 | 9.00 | 228.6 | 7.25 | 184.2 | 1.00 | 25.4 | 8 | 3 1/2 |
| 4 | 4 1/2 | 114.3 | 7.00 | 177.8 | 10.00 | 254.0 | 7.88 | 200.2 | 1.00 | 25.4 | 8 | 4 |
| 5 | 5 9/16 | 141.3 | 8.38 | 212.9 | 11.00 | 279.4 | 9.25 | 235.0 | 1.00 | 25.4 | 8 | 5 |
| 6 | 6 5/8 | 168.3 | 9.75 | 247.7 | 12.50 | 317.5 | 10.62 | 269.7 | 1.00 | 25.4 | 12 | 6 |
| 8 | 8 5/8 | 219.1 | 12.00 | 304.8 | 15.00 | 381.0 | 13.00 | 330.2 | 1.12 | 28.4 | 12 | 8 |
| 10 | 10 3/4 | 273.1 | 14.12 | 358.6 | 17.50 | 444.5 | 15.25 | 387.4 | 1.25 | 31.8 | 16 | 10 |
| 12 | 12 3/4 | 323.9 | 16.50 | 419.1 | 20.50 | 520.7 | 17.75 | 450.9 | 1.38 | 35.1 | 16 | 12 |
| 14 | 14 | 355.6 | 19.00 | 482.6 | 23.00 | 584.2 | 20.25 | 514.4 | 1.38 | 35.1 | 20 | 14 |
| 16 | 16 | 406.4 | 21.12 | 536.4 | 25.50 | 647.7 | 22.50 | 571.5 | 1.50 | 38.1 | 20 | 16 |
| 18 | 18 | 457.2 | 23.38 | 593.9 | 28.00 | 711.2 | 24.75 | 628.7 | 1.50 | 38.1 | 24 | 18 |
| 20 | 20 | 508.0 | 25.50 | 647.7 | 30.50 | 774.7 | 27.00 | 685.8 | 1.62 | 41.1 | 24 | 20 |
| 24 | 24 | 609.6 | 30.25 | 768.4 | 36.00 | 914.4 | 32.00 | 812.8 | 1.88 | 47.8 | 24 | 24 |
