All dimensions are in "mm" unless noted otherwise.
Dimensions of Class 900 RF Weld Neck Flanges Series B as per ASME B16.47.
| Nominal Pipe Size |
OD of Flange (O) |
Thickness of Flange (C) |
Length thru Hub (V) |
Dia of Hub at base (X) |
Dia of Hub at end (A) |
Dia of Raised Face (R) |
Dia of Bolt Circle |
No of Bolt Holes |
Dia of Bolt Holes |
Dia of Bolt |
Fillet Radius (r1) |
Approx Weight (kg) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 26 | 1022.4 | 134.9 | 258.8 | 743 | 660.4 | 962 | 901.7 | 20 | 66.5 | 63.5 | 11.2 | 538 |
| 28 | 1104.9 | 147.6 | 276.4 | 797.1 | 711.2 | 819.2 | 971.6 | 20 | 73.2 | 69.9 | 12.7 | 675 |
| 30 | 1181.1 | 155.4 | 289.1 | 850.9 | 762 | 876.3 | 1035.1 | 20 | 79.2 | 76.2 | 12.7 | 798 |
| 32 | 1238.3 | 160.3 | 303.3 | 908.1 | 812.8 | 927.1 | 1092.2 | 20 | 79.2 | 76.2 | 12.7 | 898 |
| 34 | 1314.5 | 171.5 | 319 | 962.2 | 863.6 | 990.6 | 1155.7 | 20 | 85.9 | 82.6 | 14.2 | 1063 |
| 36 | 1346.2 | 173 | 325.4 | 1016 | 914.4 | 1028.7 | 1200.2 | 24 | 79.2 | 76.2 | 14.2 | 1078 |
| 38 | 1460.5 | 190.5 | 352.6 | 1073.2 | 965.2 | 1098.6 | 1289.1 | 20 | 91.9 | 88.9 | 19.1 | 1445 |
| 40 | 1511.3 | 196.9 | 363.5 | 1127.3 | 1016 | 1162.1 | 1339.9 | 24 | 91.9 | 88.9 | 20.6 | 1529 |
| 42 | 1562.1 | 206.2 | 371.3 | 1176.3 | 1066.8 | 1212.9 | 1390.7 | 24 | 91.9 | 88.9 | 20.6 | 1666 |
| 44 | 1648 | 214.4 | 390.7 | 1234.9 | 1117.6 | 1270 | 1463.5 | 24 | 98.6 | 95.3 | 22.4 | 1939 |
| 46 | 1733.6 | 225.6 | 411 | 1292.4 | 1168.4 | 1333.5 | 1536.7 | 24 | 104.6 | 101.6 | 22.4 | 2265 |
| 48 | 1784.4 | 233.4 | 419.1 | 1343.2 | 1219.2 | 1384.3 | 1587.5 | 24 | 104.6 | 101.6 | 23.9 | 2433 |
Note that the dimensions of Series B flanges are same as Series A flanges for sizes NPS 38 and above in Class 900 rating.