Dimensions of Type 6B flanges for 3000 psi (20.7 MPa) rated working pressure.

Type 6B flanges are of the ring joint type and are not designed for face-to-face make-up. The connection make-up bolting force reacts on the metallic ring gasket.

All dimensions are in "mm" unless noted otherwise. Only flange sizes are in imperial units.

API 6A Flange Dimensions

  
Size B1 O C K P E X BC N H Y A B2 Ring
Number
R or RX
2 1/16" 53.2 215 46.1 124 95.25 7.9 104.8 165.1 8 26 109.6 60.3 50.0 24
2 9/16" 65.9 245 49.3 137 107.95 7.9 123.8 190.5 8 29 112.7 73.0 59.7 27
3 1/8" 81.8 240 46.1 156 123.83 7.9 127.0 190.5 8 26 109.5 88.9 74.4 31
4 1/16" 108.7 290 52.4 181 149.23 7.9 158.8 235.0 8 32 122.2 114.3 98.0 37
5 1/8" 131.0 350 58.8 216 180.98 7.9 190.5 279.4 8 35 134.9 141.3 122.9 41
7 1/16" 181.0 380 63.5 241 211.15 7.9 235 317.5 12 32 147.6 168.3 147.1 45
9" 229.4 470 71.5 308 269.88 7.9 298.5 393.7 12 39 169.9 219.1 189.7 49
11" 280.2 545 77.8 362 323.85 7.9 368.3 469.9 16 39 192.1 273 237.2 53
13 5/8 " 346.9 610 87.4 419 381.00 7.9 419.1 533.4 20 39 - - - 57
16 3/4" 426.2 705 100.1 524 469.90 11.2 508.0 616.0 20 45 - - - 66
20 3/4" 527.8 855 120.7 648 584.20 12.7 622.9 749.3 20 54 - - - 74