01
Weld Neck Flange
ANSI B16.5 Class 400 Forged Flanges
02
Threaded Flange
03
Slip On Flange
04
Lap Joint Flange
05
Socket Weld Flange
06
Blind Flange
| Nom. Pipe Size | O | T | R | X | #/Dia of Holesa | Bolt Circle Dia | B | B2b | B3 | H | L | L2 | L3c | r | C | D | Thr |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ½ | 3.75 | 0.56 | 1.38 | 1.5 | 4-0.63 | 2.62 | 0.88 |
|
0.9 | 0.84 | 0.88 | 2.06 | 0.88 | 0.12 | 0.93 | 0.38 | 0.62 |
| ¾ | 4.62 | 0.62 | 1.69 | 1.88 | 4-0.75 | 3.25 | 1.09 | 1.11 | 1.05 | 1 | 2.25 | 1 | 0.12 | 1.14 | 0.44 | 0.62 | |
| 1 | 4.88 | 0.69 | 2 | 2.12 | 4-.075 | 3.5 | 1.36 | 1.38 | 1.32 | 1.06 | 2.44 | 1.06 | 0.12 | 1.41 | 0.5 | 0.69 | |
| 1¼ | 5.25 | 0.81 | 2.5 | 2.5 | 4-0.75 | 3.88 | 1.7 | 1.72 | 1.66 | 1.12 | 2.62 | 1.12 | 0.19 | 1.75 | 0.56 | 0.81 | |
| 1½ | 6.12 | 0.88 | 2.88 | 2.75 | 4-0.88 | 4.5 | 1.95 | 1.97 | 1.9 | 1.25 | 2.75 | 1.25 | 0.25 | 1.99 | 0.62 | 0.88 | |
| 2 | 6.5 | 1 | 3.62 | 3.31 | 8-0.75 | 5 | 2.44 | 2.46 | 2.38 | 1.44 | 2.88 | 1.44 | 0.31 | 2.5 | 0.69 | 1.12 | |
| 2½ | 7.5 | 1.12 | 4.12 | 3.94 | 8-0.88 | 5.88 | 2.94 | 2.97 | 2.88 | 1.62 | 3.12 | 1.62 | 0.31 | 3 | 0.75 | 1.25 | |
| 3 | 8.25 | 1.25 | 5 | 4.62 | 8-0.88 | 6.62 | 3.57 | 3.6 | 3.5 | 1.81 | 3.25 | 1.81 | 0.38 | 3.63 | 0.81 | 1.38 | |
| 3½ | 9 | 1.38 | 5.5 | 5.25 | 8-1.00 | 7.25 | 4.07 | 4.1 | 4 | 1.94 | 3.38 | 1.94 | 0.38 | 4.13 | …. | 1.56 | |
| 4 | 10 | 1.38 | 6.19 | 5.75 | 8-1.00 | 7.88 | 4.57 | 4.6 | 4.5 | 2 | 3.5 | 2 | 0.44 | 4.63 | …. | 1.44 | |
| 5 | 11 | 1.5 | 7.31 | 7 | 8-1.00 | 9.25 | 5.66 | 5.69 | 5.56 | 2.12 | 4 | 2.12 | 0.44 | 5.69 | …. | 1.69 | |
| 6 | 12.5 | 1.62 | 8.5 | 8.12 | 12-1.00 | 10.62 | 6.72 | 6.75 | 6.63 | 2.25 | 4.06 | 2.25 | 0.5 | 6.75 | …. | 1.81 | |
| 8 | 15 | 1.88 | 10.62 | 10.25 | 12-1.12 | 13 | 8.72 | 8.75 | 8.63 | 2.69 | 4.62 | 2.69 | 0.5 | 8.75 | …. | 2 | |
| 10 | 17.5 | 2.12 | 12.75 | 12.62 | 16-1.25 | 15.25 | 10.88 | 10.92 | 10.75 | 2.88 | 4.88 | 4 | 0.5 | 10.88 | …. | 2.19 | |
| 12 | 20.5 | 2.25 | 15 | 14.75 | 16-1.38 | 17.75 | 12.88 | 12.92 | 12.75 | 3.12 | 5.38 | 4.25 | 0.5 | 12.94 | …. | 2.38 | |
| 14 | 23 | 2.38 | 16.25 | 16.75 | 20-1.38 | 20.25 | 14.14 | 14.18 | 14 | 3.31 | 5.88 | 4.62 | 0.5 | 14.19 | …. | 2.5 | |
| 16 | 25.5 | 2.5 | 18.5 | 19 | 20-1.50 | 22.5 | 16.16 | 16.19 | 16 | 3.69 | 6 | 5 | 0.5 | 16.19 | …. | 2.69 | |
| 18 | 28 | 2.62 | 21 | 21 | 24-1.50 | 24.75 | 18.18 | 18.2 | 18 | 3.88 | 6.5 | 5.38 | 0.5 | 18.19 | …. | 2.75 | |
| 20 | 30.5 | 2.75 | 23 | 23.12 | 24-1.62 | 27 | 20.2 | 20.25 | 20 | 4 | 6.62 | 5.75 | 0.5 | 20.19 | …. | 2.88 | |
| 22 | 33 | 2.88 | 25.25 | 25.25 | 24-1.75 | 29.25 | 22.22 | 22.25 | 22 | 4.25 | 6.75 | 6 | 0.5 | …. | …. | — | |
| 24 | 36 | 3 | 27.25 | 27.62 | 24-1.88 | 32 | 24.25 | 24.25 | 24 | 4.5 | 6.88 | 6.25 | 0.5 | 24.19 | …. | 3.25 |
Dimensions are in inches.
(a)- Bolt hole diameter 1/8 in. larger than bolt diameter. (b)- Standard bore dimensions provided. See bore chart for other wall thicknesses. (c)- This dimension is commonly associated with “true” lap joints. Industry standard is to make to the slip on length through the hub.
