ANSI / ASME B16.5 Class 2500 Lap Joint Flange Dimensions
| Nominal Pipe Size | Outside Diameter (O) | Thickness (T) | Length Thru Hub (Y) | Hub Diameter (X) | Radius (r) | Bore (B) | Approximate Weight (lbs) | Bolt Circle (C) | Number of Holes | Diameter of Holes |
|---|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 5.25 | 1.19 | 1.56 | 1.69 | 0.13 | 0.90 | 7 | 3.50 | 4 | 0.88 |
| 3/4 | 5.50 | 1.25 | 1.69 | 2.00 | 0.13 | 1.11 | 8 | 3.75 | 4 | 0.88 |
| 1 | 6.25 | 1.38 | 1.88 | 2.25 | 0.13 | 1.38 | 11 | 4.25 | 4 | 1.00 |
| 1 1/4 | 7.25 | 1.50 | 2.06 | 2.88 | 0.19 | 1.72 | 16 | 5.13 | 4 | 1.13 |
| 1 1/2 | 8.00 | 1.75 | 2.38 | 3.13 | 0.25 | 1.97 | 22 | 5.75 | 4 | 1.25 |
| 2 | 9.25 | 2.00 | 2.75 | 3.75 | 0.31 | 2.46 | 38 | 6.75 | 8 | 1.13 |
| 2 1/2 | 10.50 | 2.25 | 3.13 | 4.50 | 0.31 | 2.97 | 55 | 7.75 | 8 | 1.25 |
| 3 | 12.00 | 2.63 | 3.63 | 5.25 | 0.38 | 3.60 | 83 | 9.00 | 8 | 1.38 |
| 4 | 14.00 | 3.00 | 4.25 | 6.50 | 0.38 | 4.60 | 125 | 10.75 | 8 | 1.63 |
| 5 | 16.50 | 3.63 | 5.13 | 8.00 | 0.44 | 5.69 | 210 | 12.75 | 8 | 1.88 |
| 6 | 19.00 | 4.25 | 6.00 | 9.25 | 0.44 | 6.75 | 325 | 14.50 | 8 | 2.13 |
| 8 | 21.75 | 5.00 | 7.00 | 12.00 | 0.50 | 8.75 | 485 | 17.25 | 12 | 2.13 |
| 10 | 26.50 | 6.50 | 9.00 | 14.75 | 0.50 | 10.92 | 930 | 21.25 | 12 | 2.63 |
| 12 | 30.00 | 7.25 | 10.00 | 17.38 | 0.50 | 12.92 | 1100 | 24.38 | 12 | 2.88 |
*Use 25.4 as a factor to convert into mm.