Solid Weld Neck Flanges

Type and Construction

The solid weld neck flanges are in accordance with EEMUA 234, Section 3 for 16 and 20 bar systems. The range of sizes covered is ½ in./ 16 mm to 36 in./914 mm Class 150. Other sizes are available on request. Drilling and outside diameter dimensions of flange sizes ½ in./16 mm-24 in./610 mm are in accordance with ANSI B16.5 and BS 1560, whereas the larger sizes, 28 in./711 mm -36 in./914 mm are in accordance with MSS SP-44. The recommended bolting is in accordance with ASTM B150 alloy UNS C63000.

Dimensions

Dimensions are based on EEMUA -234, Section 3, Table 3.2-3.3.

Tolerances

The tolerances are based on EEMUA – 234, Section 3, Table 3.4.

            16 bar 20 bar 16 bar 20 bar 16 bar 20 bar        
Nominal Size  O.D. of Flange Thickn. of Flange Dia of Hub Hub dia at weld Chamfer Length Through Hub Bore of Flange Thickn. of Hub at Welding End Approx. Weight Parallel Length of Hub Dia of Bolt Circle Drilling Dia of Bolt Holes
    D b d6 d3 H d7 d7 S1 min S1 min     h K No. Of Bolts d2
in mm mm mm mm mm mm mm mm mm mm kg kg mm mm   mm
½ 16 89 14 23 16 48 u
s
e

2
0

b
a
r
12.00 u
s
e

2
0

b
a
r
2.0 u
s
e

2
0

b
a
r
0.7 8 60.3 4 15.9
¾ 25 98 16 32 25 52 21.00 2.0 1.0 7 69.8 4 15.9
1 30 108 16 42 30 56 25.00 2.5 1.3 8 79.4 4 15.9
38 117 17 51 38 57 33.03 2.5 1.7 8 88.9 4 15.9
44.5 127 20 61 44.5 62 39.53 2.5 2.3 7 98.4 4 15.9
2 57 152 25 73 57 64 52.16 2.5 4.1 9 120.6 4 19.0
76.1 178 27 91 76.1 70 71.23 2.5 6.1 8 139.7 4 19.0
3 88.9 190 27 105 88.9 70 84.08 2.5 7.1 8 152.4 4 19.0
4 108 229 27 135 108 76 102.13 3.0 10.2 8 190.5 8 19.0
6 159 279 27 192 159 89 153.75 152.38 3.0 3.5 15.5 15.8 8 241.3 8 22.2
8 219.1 343 31 246 219.1 98 211.10 210.10 4.0 4.5 27.7 28.0 8 298.4 8 22.2
10 267 406 31 305 267 98 257.97 255.93 4.5 5.5 38.5 39.3 8 362.0 12 25.4
12 323.9 483 35 365 323.9 98 312.83 309.74 5.5 7.0 61.6 62.9 8 431.8 12 25.4
14 368 533 41 400 368 99 354.22 351.00 6.5 8.0 86.8 88.4 8 476.2 12 28.6
16 419 597 43 457 419 106 404.17 399.84 7.0 9.0 114.2 115.6 8 539.8 16 28.6
18 457.2 635 45 505 457.2 113 441.50 438.50 8.0 9.5 136.0 140.7 8 577.8 16 31.8
20 508 698 45 559 508 118 490.50 486.50 8.5 11.0 164.6 168.4 8 635.0 20 31.8
24 610 813 49 664 610 137 589.50 584.50 10.5 13.0 247.7 253.7 8 749.3 20 34.9
28 711 927 72 748 711 145 687.50 681.40 12.0 15.0 453.0 461.1 8 864.0 28 34.9
32 813 1060 72 876 813 160 786.50 779.50 13.5 17.0 599.0 611.1 8 978.0 28 41.1
36 914 1168 72 984 914 175 883.50 876.50 15.5 19.0 741.0 755.7 8 1086.0 32 41.1

It should be noted that although these flanges are flat faced, inside bolt circle gaskets shall be used and special care should be taken to avoid overtightening the bolting.