ANSI B16.5 Forged Flanges
Class 2500 Flange Dimensions
ASME B16.5
Class 2500 is the highest B16.5 pressure class, used in the most severe high-pressure applications. Sizes are limited to NPS 1/2 through 12. All dimensions are in inches.
| NPS | Flange OD | Thickness (min) | RF Diameter | Bolt Circle | # Bolts | Bolt Dia. | Hub Dia. | WN Length | Bore |
|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 5.25 | 1.19 | 1.38 | 3.50 | 4 | 3/4 | 1.19 | 3.25 | 0.88 |
| 3/4 | 5.50 | 1.25 | 1.69 | 3.75 | 4 | 3/4 | 1.50 | 3.38 | 1.09 |
| 1 | 6.25 | 1.38 | 2.00 | 4.25 | 4 | 7/8 | 1.94 | 3.56 | 1.36 |
| 1-1/2 | 8.00 | 1.75 | 2.88 | 5.75 | 4 | 1-1/4 | 2.56 | 4.25 | 1.97 |
| 2 | 9.25 | 2.00 | 3.62 | 6.75 | 8 | 1 | 3.06 | 4.38 | 2.44 |
| 2-1/2 | 10.50 | 2.25 | 4.12 | 7.75 | 8 | 1-1/8 | 3.56 | 4.88 | 2.94 |
| 3 | 12.00 | 2.62 | 5.00 | 9.00 | 8 | 1-1/4 | 4.25 | 5.50 | 3.57 |
| 4 | 14.00 | 3.00 | 6.19 | 10.75 | 8 | 1-1/2 | 5.31 | 6.25 | 4.57 |
| 5 | 16.50 | 3.62 | 7.31 | 13.00 | 8 | 1-3/4 | 6.44 | 7.00 | 5.66 |
| 6 | 19.00 | 4.25 | 8.50 | 15.25 | 8 | 2 | 7.56 | 7.88 | 6.72 |
| 8 | 21.75 | 5.00 | 10.62 | 17.75 | 12 | 2 | 9.69 | 9.00 | 8.72 |
| 10 | 26.50 | 6.50 | 12.75 | 22.00 | 12 | 2-1/2 | 11.75 | 10.88 | 10.88 |
| 12 | 30.00 | 7.25 | 15.00 | 25.25 | 12 | 2-3/4 | 13.75 | 12.00 | 12.88 |
