Dimension of Nonmetallic Full Face Gaskets, Class 900, ASME B16.21
used with RF flanges ASME B16.5
OTHER PRESSURE CLASSES
900
| NPS | Inside Dia. (ID) |
Outside Dia. (OD) |
No.of Bolt Holes |
Bolt Hole Dia. |
Bolt Circle Dia. (BCD) |
| 1/2 | 21 | 121 | 4 | 22 | 82.6 |
| 3/4 | 27 | 130 | 4 | 22 | 88.9 |
| 1 | 33 | 149 | 4 | 25 | 101.6 |
| 1.1/4 | 42 | 159 | 4 | 25 | 111.3 |
| 1.1/2 | 49 | 178 | 4 | 28 | 124.0 |
| 2 | 60 | 216 | 8 | 25 | 165.1 |
| 2.1/2 | 73 | 245 | 8 | 28 | 190.5 |
| 3 | 89 | 241 | 8 | 25 | 190.5 |
| 4 | 114 | 292 | 8 | 31 | 235.0 |
| 5 | 141 | 349 | 8 | 35 | 279.4 |
| 6 | 168 | 381 | 12 | 31 | 317.5 |
| 8 | 219 | 470 | 12 | 38 | 393.7 |
| 10 | 273 | 546 | 16 | 38 | 469.9 |
| 12 | 324 | 610 | 20 | 38 | 533.4 |
| 14 | 356 | 641 | 20 | 41 | 558.8 |
| 16 | 406 | 705 | 20 | 44 | 616.0 |
| 18 | 457 | 787 | 20 | 50 | 685.8 |
| 20 | 508 | 857 | 20 | 54 | 749.3 |
| 24 | 610 | 1041 | 20 | 66 | 901.7 |
General notes..
- Dimensions are in millimeters unless otherwise indicated.
- Never use full face gaskets on flanges with a raised face, or other faces. Flanges for full face gaskets should only be used on completely smooth faces.
