| Nominal Pipe Size | Outside Diameter of Flange | Diameter of Raised Face | Thickness of Flanges Min. | Diameter of Hub | Hub Diameter Beginning of Chamfer | Length Through Hub | Bore | Diameter of Bolt Circle | Diameter of Bolt Holes | Number of Bolts | Approxi-mate Weight kgs |
| NPS | O | R | tf | X | A | Y | B | W | I | n | |
| 1/2 | 120 | 34.9 | 22.3 | 38 | 21.3 | 60 | 15.8 | 82.6 | 22.2 | 4 | 1.86 |
| 3/4 | 130 | 42.9 | 25.4 | 44 | 26.7 | 70 | 21.0 | 88.9 | 22.2 | 4 | 2.55 |
| 1 | 150 | 50.8 | 28.6 | 52 | 33.4 | 73 | 26.6 | 101.6 | 25.4 | 4 | 3.78 |
| 1 1/4 | 160 | 63.5 | 28.6 | 64 | 42.2 | 73 | 35.1 | 111.1 | 25.4 | 4 | 4.40 |
| 1 1/2 | 180 | 73.0 | 31.8 | 70 | 48.3 | 83 | 40.9 | 123.8 | 28.6 | 4 | 6.12 |
| 2 | 215 | 92.1 | 38.1 | 105 | 60.3 | 102 | 52.5 | 165.1 | 25.4 | 8 | 10.86 |
| 2 1/2 | 245 | 104.8 | 41.3 | 124 | 73.0 | 105 | 62.7 | 190.5 | 28.6 | 8 | 15.20 |
| 3 | 265 | 127.0 | 47.7 | 133 | 88.9 | 117 | 77.9 | 203.2 | 31.8 | 8 | 19.61 |
| 4 | 310 | 157.2 | 54.0 | 162 | 114.3 | 124 | 102.3 | 241.3 | 34.9 | 8 | 29.63 |
| 5 | 375 | 185.7 | 73.1 | 197 | 141.3 | 156 | 128.2 | 292.1 | 41.3 | 8 | 56.87 |
| 6 | 395 | 215.9 | 82.6 | 229 | 168.3 | 171 | 154.1 | 317.5 | 38.1 | 12 | 68.10 |
| 8 | 485 | 269.9 | 92.1 | 292 | 219.1 | 213 | 202.7 | 393.7 | 44.5 | 12 | 116.26 |
| 10 | 585 | 323.8 | 108.0 | 368 | 273.0 | 254 | 254.5 | 482.6 | 50.8 | 12 | 200.20 |
| 12 | 675 | 381.0 | 123.9 | 451 | 323.8 | 283 | 304.7 | 571.5 | 54.0 | 16 | 300.10 |
| 14 | 750 | 412.8 | 133.4 | 495 | 355.6 | 298 | 336.5 | 635.0 | 60.3 | 16 | 392.98 |
| 16 | 825 | 469.9 | 146.1 | 552 | 406.4 | 311 | 387.3 | 704.8 | 66.7 | 16 | 498.22 |
| 18 | 915 | 533.4 | 162.0 | 597 | 457.0 | 327 | 437.9 | 774.7 | 73.0 | 16 | 651.35 |
| 20 | 985 | 584.2 | 177.8 | 641 | 508.0 | 356 | 488.9 | 831.8 | 79.4 | 16 | 795.97 |
| 24 | 1170 | 692.2 | 203.2 | 762 | 610.0 | 406 | 590.9 | 990.6 | 92.1 | 16 | 1265.87 |
The welding neck flange is the best designed butt-welded flange of those currently available becuase of its inherent structural value.
Regardless of custom sizing or specifications, the fundamental design of most flanges falls under six common styles created to close, connect, cover, or support pipes and pipe systems.
Below you will find a short description and definition of each type, completed with an detailed image.
Our team are highly trained and experienced in servicing and producing all types of steel supplies. Whether you've got a large construction project, or need parts for industrial machinery, our team of steel fabrication consultants will ensure that your project is provided with the parts you need, when you need them.
