ANSI B16.5 Class 150 Lap Joint Flanges
| NPS (Nominal Pipe Size) | Outside Diameter (O) (mm) | Thickness (T) (mm) | Diameter of Bolt Circle (C) (mm) | Diameter of Bolt Holes (in) | Number of Bolts |
|---|---|---|---|---|---|
| 1/2 | 89 | 9.7 | 60.5 | 5/8 | 4 |
| 3/4 | 99 | 11.2 | 69.8 | 5/8 | 4 |
| 1 | 108 | 12.7 | 79.2 | 5/8 | 4 |
| 1 1/4 | 117 | 14.2 | 88.9 | 5/8 | 4 |
| 1 1/2 | 127 | 15.9 | 98.6 | 5/8 | 4 |
| 2 | 152 | 17.5 | 120.6 | 3/4 | 4 |
| 2 1/2 | 178 | 20.6 | 139.7 | 3/4 | 4 |
| 3 | 190 | 22.4 | 152.4 | 3/4 | 4 |
| 3 1/2 | 216 | 22.4 | 177.8 | 3/4 | 8 |
| 4 | 229 | 22.4 | 190.5 | 3/4 | 8 |
| 5 | 254 | 22.4 | 215.9 | 7/8 | 8 |
| 6 | 279 | 23.9 | 241.3 | 7/8 | 8 |
| 8 | 343 | 26.9 | 298.4 | 7/8 | 8 |
| 10 | 406 | 28.4 | 362 | 1 | 12 |
| 12 | 483 | 30.2 | 431.8 | 1 | 12 |
| 14 | 553 | 33.3 | 476.2 | 1 1/8 | 12 |
| 16 | 597 | 35.1 | 539.8 | 1 1/8 | 16 |
| 18 | 635 | 38.1 | 577.8 | 1 1/4 | 16 |
| 20 | 698 | 41.1 | 635 | 1 1/4 | 20 |
| 22 | 749 | 44.4 | 692.2 | 1 3/8 | 20 |
| 24 | 813 | 46 | 749.3 | 1 3/8 | 20 |