COMPOSITE BLIND FLANGES

Type and Construction

The composite blind flanges are in accordance with manufacturer’s specification. The range of sizes covered is ½ in./16 mm to 36 in./914 mm Class 150. 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 blind flanges are suitable for use both 16 and 20 bar systems.

The composite blind flanges are manufactured from forged carbon steel in accordance with ASTM A105 cladded with copper nickel disk. In contrast to raised face blind flanges in accordance to ANSI B16.5, the supplied composite flanges are considered as flat face, since the diameter of the copper nickel disk d1 is equivalent to the flange diameter d4 weld neck stub end in accordance with EEMUA 234, Section 1A. By these means, uniform contact over the weld neck stub end faces is ensured. The recommended bolting is in accordance with ASTM A193-B7. Unless otherwise specified the flanges are protected by hot dipped galvanising. Additional organic coatings such as polyamide epoxy are available on request. Solid blind flanges are available on request.

Tolerances

Tolerances are equivalent to the dimensions for weld neck backing flanges based on EEMUA – 234, Section 1B, Table 1.5.2.

Nom. Spec. Flange   Diameter of Bolt Holes  Flange Diameter of No. Of Approx.
Size Size Diameter K d2  Thickness Disk Bolt Total Weight
in mm D mm mm in mm b min mm d1 mm Holes (kg)
½ 16 89 60.3 5/8 15.9 14 40 4 0.82
¾ 25 98 69.8 5/8 15.9 14 50 4 1.04
1 30 108 79.4 5/8 15.9 14 50 4 1.31
38 117 88.9 5/8 15.9 14 70 4 1.58
44.5 127 98.4 5/8 15.9 14 80 4 1.90
2 57 152 120.6 3/4 19.0 18 99 4 3.01
76.1 178 139.7 3/4 19.0 18 120 4 4.68
3 88.9 190 152.4 3/4 19.0 19 130 4 5.70
4 108 229 190.5 3/4 19.0 24 158 8 8.67
6 159 279 241.3 7/8 22.2 27 212 8 15.46
8 219.1 343 298.4 7/8 22.2 31 270 8 24.90
10 267 406 362.0 1 25.4 38 320 12 41.23
12 323.9 483 431.8 1 25.4 41 370 12 70.55
14 368 533 476.2 1 1/8 28.6 45 430 12 93.16
16 419 597 539.8 1 1/8 28.6 51 482 16 123.99
18 457.2 635 577.8 1 1/4 31.8 52 530 16 147.55
20 508 698 635.0 1 1/4 31.8 58 585 20 191.00
24 610 813 749.3 1 3/8 34.9 71 685 20 285.74
28 711 927 864.0 1 3/8 34.9 81 800 28 434.66
32 813 1060 978.0 1 5/8 41.1 95 905 28 665.63
36 914 1168 1086.0 1 5/8 41.1 105 1000 32 886.43