Here is the dimensions chart for ASA 300 flanges in millimeters, covering sizes from 15NB to 600NB:
| Nominal Pipe Size (NB) | Outer Diameter (OD) (D) | Bore Diameter (J) | Thickness (H) | Number of Bolt Holes | Bolt Hole Diameter (l) | Pitch Circle Diameter (PCD) (k) |
|---|---|---|---|---|---|---|
| 15 NB | 95.3 | 22.4 | 14.3 | 4 | 12.7 | 66.7 |
| 20 NB | 117.5 | 27.7 | 15.9 | 4 | 15.9 | 82.6 |
| 25 NB | 123.8 | 34.5 | 17.5 | 4 | 15.9 | 88.9 |
| 32 NB | 133.4 | 43.2 | 19.1 | 4 | 15.9 | 98.4 |
| 40 NB | 155.6 | 49.5 | 20.6 | 4 | 19.1 | 114.3 |
| 50 NB | 165.1 | 62.0 | 22.2 | 8 | 15.9 | 127.0 |
| 65 NB | 190.5 | 74.7 | 25.4 | 8 | 19.1 | 149.2 |
| 80 NB | 209.6 | 90.7 | 28.6 | 8 | 19.1 | 168.3 |
| 100 NB | 254.0 | 116.1 | 31.8 | 8 | 19.1 | 200.0 |
| 125 NB | 279.4 | 143.8 | 34.9 | 8 | 19.1 | 235.0 |
| 150 NB | 317.5 | 170.7 | 36.5 | 12 | 19.1 | 269.9 |
| 200 NB | 381.0 | 221.5 | 41.3 | 12 | 22.2 | 330.2 |
| 250 NB | 444.5 | 276.4 | 47.6 | 16 | 25.4 | 387.4 |
| 300 NB | 520.7 | 327.2 | 50.8 | 16 | 28.6 | 450.9 |
| 350 NB | 584.2 | 359.2 | 54.0 | 20 | 28.6 | 514.4 |
| 400 NB | 647.7 | 410.5 | 57.2 | 20 | 31.8 | 571.5 |
| 450 NB | 711.2 | 461.8 | 60.3 | 24 | 31.8 | 628.7 |
| 500 NB | 774.7 | 513.1 | 63.5 | 24 | 31.8 | 685.8 |
| 600 NB | 914.4 | 615.9 | 69.8 | 24 | 31.8 | 812.8 |