Dimensions of Class 900 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 | 4.75 | 121 | 4 | 0.88 | 3.25 | 82.6 |
| 3/4 | 1.06 | 27 | 5.13 | 130 | 4 | 0.88 | 3.50 | 88.9 |
| 1 | 1.31 | 33 | 5.88 | 149 | 4 | 1.00 | 4.00 | 101.6 |
| 1 1/4 | 1.66 | 42 | 6.25 | 159 | 4 | 1.00 | 4.38 | 111.3 |
| 1 1/2 | 1.91 | 49 | 7.00 | 178 | 4 | 1.13 | 4.88 | 124.0 |
| 2 | 2.38 | 60 | 8.50 | 216 | 8 | 1.00 | 6.50 | 165.1 |
| 2 1/2 | 2.88 | 73 | 9.63 | 245 | 8 | 1.13 | 7.50 | 190.5 |
| 3 | 3.50 | 89 | 9.50 | 241 | 8 | 1.00 | 7.50 | 190.5 |
| 3 1/2 | 4.00 | 102 | 11.50 | 292 | - | - | - | 0.0 |
| 4 | 4.50 | 114 | 11.50 | 292 | 8 | 1.25 | 9.25 | 235.0 |
| 5 | 5.56 | 141 | 13.75 | 349 | 8 | 1.38 | 11.00 | 279.4 |
| 6 | 6.62 | 168 | 15.00 | 381 | 12 | 1.25 | 12.50 | 317.5 |
| 8 | 8.62 | 219 | 18.50 | 470 | 12 | 1.50 | 15.50 | 393.7 |
| 10 | 10.75 | 273 | 21.50 | 546 | 16 | 1.50 | 18.50 | 469.9 |
| 12 | 12.75 | 324 | 24.00 | 610 | 20 | 1.50 | 21.00 | 533.4 |
| 14 | 14.00 | 356 | 25.25 | 641 | 20 | 1.63 | 22.00 | 558.8 |
| 16 | 16.00 | 406 | 27.75 | 705 | 20 | 1.75 | 24.25 | 616.0 |
| 18 | 18.00 | 457 | 31.00 | 787 | 20 | 2.00 | 27.00 | 685.8 |
| 20 | 20.00 | 508 | 33.75 | 857 | 20 | 2.13 | 29.50 | 749.3 |
| 24 | 24.00 | 610 | 41.00 | 1041 | 20 | 2.63 | 35.50 | 901.7 |