Weld neck flange (also known as a high-hub flange and tapered hub flange) is a type of flange. There are two designs. The regular type is used with pipes. The long type is unsuitable for pipes and is used in process plant.A weld neck flange consists of a circular fitting with a protruding rim around the circumference. Generally machined from a forging, these flanges are typically butt welded to a pipe. The rim has a series of drilled holes that permit the flange to be affixed to another flange with bolts.

ASME B16.5 Welding Neck Flanges Class 150/300LBS Dimensions

ASME B16.5 Welding Neck Flanges Class 150/300LBS Dimensions

 

ASME B16.47 Series A Welding Neck Flanges Class 150 LBS Dimensions
NPS A B I Holes C D F E G Weight
22″ 750 533.6 35 20 46 149 610 558.8 641 106.64
26″ 870 634.6 35 24 68.5 121 675 660.4 749 149.48
28″ 925 685.6 35 28 71.5 125 725 711.2 800 168.11
30″ 985 736.6 35 28 74.5 137 780 762 857 198.67
32″ 1060 787.6 41 28 81 144 832 812.8 914 247.22
34″ 1110 838.6 41 32 82.5 149 880 863.6 965 262.48
36″ 1170 888.6 41 32 90.5 157 935 914.4 1022 317.38
38″ 1240 939.6 41 32 87.4 157 990 965.2 1073 351.81
40″ 1290 990.6 41 36 90.5 164 1040 1016 1124 378.08
42″ 1345 1041.6 41 36 97 171 1090 1066.8 1194 429.26
44″ 1405 1092.6 41 40 102 178 1145 1117.6 1245 485.2
46″ 1455 1142.6 41 40 103 186 1195 1168.4 1295 515.45
48″ 1510 1193.6 41 44 108 192 1250 1219.2 1359 568.36
50″ 1570 1244.6 48 44 111 203 1300 1270 1410 611.67
52″ 1625 1295.4 48 44 116 210 1355 1320.8 1460 676.75
54″ 1685 1346.2 48 44 121 216 1405 1371.6 1511 753.45
56″ 1745 1397 48 48 124 229 1455 1422.4 1575 823.45
58″ 1805 1447.8 48 48 129 235 1510 1473.2 1626 915.31
60″ 1855 1498.6 48 52 132 240 1560 1524 1676 958.02

 

ASME B16.47 Series A Welding Neck Flanges Class 300 LBS Dimensions
NPS A B I Holes C D F E G Weight
22″ 840 533.6 41 24 66.5 165 640 558.8 641 198.78
26″ 970 634.6 44 28 79.5 184 720 660.4 749 281.46
28″ 1035 685.6 44 28 85.5 197 775 711.2 800 341.08
30″ 1090 736.6 48 28 92 210 825 762 857 389.06
32″ 1150 787.6 51 28 98.5 222 880 812.8 914 451.27
34″ 1205 838.6 51 28 102 232 935 863.6 965 505.21
36″ 1270 888.6 54 32 105 241 990 914.4 1022 566.04
38″ 1170 939.6 41 32 108 181 995 965.2 1029 320.29
40″ 1240 990.6 44 32 114 194 1050 1016 1086 386.86
42″ 1290 1041.6 44 32 119 200 1100 1066.8 1137 420.78
44″ 1355 1092.6 48 32 124 206 1150 1117.6 1194 477.69
46″ 1415 1142.6 51 28 129 216 1205 1168.4 1245 547.53
48″ 1465 1193.6 51 32 133 224 1255 1219.2 1314 579.42
50″ 1530 1244.6 54 32 140 232 1305 1270 1359 660.62
52″ 1580 1295.4 54 32 144 238 1355 1320.8 1410 704.46
54″ 1660 1346.2 60 28 152 252 1410 1371.6 1467 859.88
56″ 1710 1397 60 28 154 260 1465 1422.4 1518 909.22
58″ 1760 1447.8 60 32 159 267 1515 1473.2 1575 954.56
60″ 1810 1498.6 60 32 164 273 1585 1524 1620 1034.68

ASME B16.5 Welding Neck Flanges Class 400-2500 LBS Dimensions

ASME B16.47 Series A Welding Neck Flanges Class 400 LBS Dimensions
NPS A B I Holes C D F E G Weight
26″ 971.5 660 47.6 28 88.9 193.6 727.1 660.4 749.3 278.2
28″ 1035 711 50.8 28 95.3 206.4 782.6 711.2 800.1 331.05
30″ 1092.2 762 54 28 101.6 219.1 836.6 762 857.2 380.6
32″ 1149.4 813 54 28 108 231.8 889 812.8 914.4 440.19
34″ 1206.5 864 54 28 111.1 241.3 944.5 863.6 965.2 493.91
36″ 1270 914 54 32 114.3 250.8 1000.1 914.4 1022.3 558.47
38″ 1206.5 965 47.6 32 123.8 206.4 1028.3 965.2 1035.1 382.14
40″ 1270 1016 50.8 32 130.2 215.9 1054.3 1016 1092.2 426.85
42″ 1320.8 1067 50.8 32 133.3 223.8 1108.1 1066.8 1143 461.35
44″ 1384.3 1118 54 32 139.7 233.3 1158.9 1117.6 1200.1 527.39
46″ 1441.5 1168 54 36 146.1 244.5 1212.9 1168.4 1257.3 589.2
48″ 1511.3 1219 60.3 28 152.4 257.2 1266.8 1219.2 1308.1 701.2
50″ 1568.5 1270 60.3 32 157.2 268.3 1320.8 1270 1362.1 762.55
52″ 1619.3 1320.8 60.3 32 161.9 276.2 1371.6 1320.8 1412.9 817.47
54″ 1801.8 1371.6 66.7 28 169.9 288.9 1425.6 1371.6 1470 1365.38
56″ 1752.6 1422.4 66.7 32 174.6 298.5 1479.5 1422.4 1527.2 1050.08
58″ 1803.4 1473.2 66.7 32 177.8 306.4 1530.4 1473.2 1578 1109.94
60″ 1886 1524 73 32 185.7 319.5 1584.3 1524 1635.1 1308.36

 

ASME B16.47 Series A Welding Neck Flanges Class 600 LBS Dimensions
NPS A B I Holes C D F E G Weight
22″ 870 533.6 47 24 95 197 640 558.8 641 297.33
26″ 1015 634.6 51 28 108 222 720 660.4 749 427.31
28″ 1075 685.6 54 28 111 235 775 711.2 800 482.76
30″ 1130 736.6 54 28 114 248 825 762 857 538.17
32″ 1194 787.6 60 28 117 260 880 812.8 914 601.33
34″ 1245 838.6 60 28 121 270 935 863.6 965 662.34
36″ 1315 888.6 60 28 124 283 990 914.4 1022 766.03
38″ 1270 939.6 60 28 152 254 995 965.2 1054 647.52
40″ 1320 990.6 60 32 159 264 1050 1016 1111 698.63
42″ 1405 1041.6 67 28 168 279 1100 1066.8 1168 862.44
44″ 1455 1092.6 67 32 173 289 1150 1117.6 1226 909.24
46″ 1510 1142.6 67 32 179 300 1205 1168.4 1276 1006.27
48″ 1595 1193.6 73 32 189 316 1255 1219.2 1283 1197.07
50″ 1670 1244.6 79 28 197 329 1305 1270 1384 1396.43
52″ 1720 1295.4 79 32 203 337 1355 1320.8 1435 1459.86
54″ 1780 1346.2 79 32 210 349 1410 1371.6 1492 1618.08
56″ 1855 1397 86 32 217 362 1465 1422.4 1543 1811.43
58″ 1905 1447.8 86 32 222 370 1515 1473.2 1600 1916.61
60″ 1995 1498.6 92 28 233 389 1585 1524 1657 2334.54

 

ASME B16.47 Series A Welding Neck Flanges Class 900 LBS Dimensions
NPS A B I Holes C D F E G Weight
26″ 1085.9 634.6 73 20 139.7 285.4 774.7 660.4 749.3 683.94
28″ 1168.4 685.6 79.4 20 142.9 298.5 831.8 711.2 800.1 804.27
30″ 1231.9 736.6 79.4 20 149.2 311.2 889 762 857.3 927.13
32″ 1314.5 787.6 85.7 20 158.8 330.2 946.2 812.8 914.4 1110.94
34″ 1397 838.6 92.1 20 165.1 349.3 1006.5 863.6 965.2 1301.24
36″ 1460.5 888.6 92.1 20 171.5 362 1063.6 914.4 1022.4 1472.55
38″ 1460.5 939.6 92.1 20 190.5 352.4 1073.2 965.2 1098.5 1437.44
40″ 1511.3 990.6 92.1 24 196.8 363.5 1127.1 1016 1162.1 1519.68
42″ 1562.1 1041.6 92.1 24 206.4 371.5 1176.3 1066.8 1212.8 1656.66
44″ 1647.8 1092.6 98.4 24 214.3 390.5 1235.1 1117.6 1270 1926.04
46″ 1733.5 1142.6 104.8 24 225.4 411.2 1292.2 1168.4 1333.5 2252.32
48″ 1784.4 1193.6 104.8 24 233.4 419.1 1343 1219.2 1384.3 2419.63