Dimensions of Class 300 Full Face Gaskets (up to 24 inches) as per ASME B16.21 to Suit ASME B16.5 Flanges.
| Nominal Pipe Size (NPS) |
Inside Diameter (ID) |
Outside Diameter (OD) |
No. of Bolt Holes |
Bolt Hole Diameter (inches) |
Bolt Circle Diameter (BCD) |
|||
|---|---|---|---|---|---|---|---|---|
| inches | mm | inches | mm | inches | mm | |||
| 1/2 | 0.84 | 21 | 3.75 | 95 | 4 | 0.63 | 2.63 | 66.8 |
| 3/4 | 1.06 | 27 | 4.62 | 117 | 4 | 0.75 | 3.25 | 82.6 |
| 1 | 1.31 | 33 | 4.88 | 124 | 4 | 0.75 | 3.50 | 88.9 |
| 1 1/4 | 1.66 | 42 | 5.25 | 133 | 4 | 0.75 | 3.88 | 98.4 |
| 1 1/2 | 1.91 | 49 | 6.12 | 155 | 4 | 0.88 | 4.50 | 114.3 |
| 2 | 2.38 | 60 | 6.50 | 165 | 8 | 0.75 | 5.00 | 127.0 |
| 2 1/2 | 2.88 | 73 | 7.50 | 191 | 8 | 0.88 | 5.88 | 149.2 |
| 3 | 3.50 | 89 | 8.25 | 210 | 8 | 0.88 | 6.63 | 168.3 |
| 3 1/2 | 4.00 | 102 | 9.00 | 229 | 8 | 0.88 | 7.25 | 184.2 |
| 4 | 4.50 | 114 | 10.00 | 254 | 8 | 0.88 | 7.88 | 200.0 |
| 5 | 5.56 | 141 | 11.00 | 279 | 8 | 0.88 | 9.25 | 235.0 |
| 6 | 6.62 | 168 | 12.50 | 318 | 12 | 0.88 | 10.63 | 269.9 |
| 8 | 8.62 | 219 | 15.00 | 381 | 12 | 1.00 | 13.00 | 330.2 |
| 10 | 10.75 | 273 | 17.50 | 445 | 16 | 1.13 | 15.25 | 387.4 |
| 12 | 12.75 | 324 | 20.50 | 521 | 16 | 1.25 | 17.75 | 450.9 |
| 14 | 14.00 | 356 | 23.00 | 584 | 20 | 1.25 | 20.25 | 514.4 |
| 16 | 16.00 | 406 | 25.50 | 648 | 20 | 1.38 | 22.50 | 571.5 |
| 18 | 18.00 | 457 | 28.00 | 711 | 24 | 1.38 | 24.75 | 628.7 |
| 20 | 20.00 | 508 | 30.50 | 775 | 24 | 1.38 | 27.00 | 685.8 |
| 24 | 24.00 | 610 | 36.00 | 914 | 24 | 1.63 | 32.00 | 812.8 |