Boltex Reference Manual

Ins_wn

Industry Standard - Welding Neck Flanges

Class 125

Nominal Size NPS Outside Diameter of Flange Thickness of Flange Length thru Hub Diameter of Hub at Base Diameter of Raised Face Diameter of Bolt Circle No. of Bolt Holes Diameter of Bolt Holes
A O C Y X R
26 in. 34.25 2.00 5.00 28.50 29.50 31.75 24 1.38
mm. 870.0 50.8 127.0 723.9 749.3 806.5 35.1
28 in. 36.50 2.06 5.06 30.75 31.50 34.00 28 1.38
  mm. 927.1 52.3 128.5 781.1 800.1 863.6 35.1
30 in. 38.75 2.13 5.13 32.75 33.75 36.00 28 1.38
mm. 984.3 54.1 130.3 831.9 857.3 814.4 35.1
32 in. 41.75 2.25 5.25 35.00 36.00 38.50 28 1.63
  mm. 1060.5 57.2 133.4 889.0 914.4 977.9 41.4
34 in. 43.75 2.31 5.31 37.00 38.00 34.25 32 1.63
mm.. 111.3 58.7 134.9 939.8 965.2 870.0 41.4
36 in. 46.00 2.38 5.38 39.25 40.25 42.75 32 1.63
  mm. 1168.4 60.5 136.7 997.0 1022.4 1085.9 41.4
38 in. 48.75 2.38 5.38 41.75 42.25 45.25 32 1.63
mm.. 1238.3 60.5 136.7 1060.5 1073.2 1149.4 41.4
40 in. 50.75 2050 5.50 43.75 44.25 47.25 36 1.63
  mm. 1289.1 63.5 139.7 1111.3 1124.0 1200.2 41.4
42 in. 53.00 2.63 5.63 46.00 47.00 49.50 36 1.63
mm.. 1346.2 66.8 143.0 1168.4 1193.8 1257.3 41.4
44 in. 55.25 2.63 5.63 48.00 49.00 51.75 40 1.63
  mm. 1403.4 66.8 143.0 1219.2 1244.6 1314.5 41.4
46 in. 57.25 2.68 5.68 50.00 51.00 53.75 40 1.63
  mm. 1454.2 68.1 144.3 1270.0 1295.4 1365.3 41.4
48 in. 59.50 2.75 5.75 52.25 53.50 56.00 44 1.63
  mm. 1511.3 69.9 146.1 1327.2 1358.9 1422.4 41.4
50 in. 61.75 2.75 5.75 54.25 55.50 58.25 44 1.88
  mm. 1568.5 69.9 146.1 1378.0 1409.7 1479.6 47.8
52 in. 64.00 2.88 5.88 56.50 57.50 60.50 44 1.88
  mm. 1625.6 73.2 149.4 1435.1 1460.5 1536.7 47.8
54 in. 66.25 3.00 6.00 58.75 59.75 62.75 44 1.88
  mm. 1682.8 76.2 152.4 1492.3 1517.7 1593.9 47.8
60 in. 73.00 3.13 6.13 65.25 66.00 69.25 52 1.88
  mm. 1854.2 79.5 155.7 1657.4 1676.4 1759.0 47.8