WELDING NECK ORIFICE FLANGES B16.36 Class 300

Nominal
Size
NPS
Outside
Diameter
of
Flange
Thickness
of
Flange
Diameter Of Raised
Face
Diameter Of Hub At Base Diameter Of Hub At Point of Welding Length
thru
Hub
Diameter Of Pressure Connection Number of
Bolt Holes
Diameter
of
Bolt
Holes
Diameter
of
Bolts
Diameter
of
Bolt
Circle
O C R X A Y TT
1 in. 4.88 1.5 2 2.12 1.32 3.25 ¼ 4 0.69  5/8 3.5
mm 124 38.1 50.8 53.8 33.5 82.6 6.4 17.5 15.9 88.9
1 ½ in. 6.12 1.5 2.88 2.75 1.9 3.38 ¼ 4 0.81 ¾ 4.5
mm 155.4 38.1 73.2 69.9 48.3 85.9 6.4 20.6 19.1 114.3
2 in. 6.5 1.5 3.62 3.31 2.38 3.38 ¼ 8 0.69  5/8 5
mm 165.1 38.1 91.9 84.1 60.5 85.9 6.4 17.5 15.9 127
2 ½ in. 7.5 1.5 4.12 3.94 2.88 3.5 ¼ 8 0.81 ¾ 5.88
mm 190.5 38.1 104.6 100.1 73.2 88.9 6.4 20.6 19.1 149.4
3 in. 8.25 1.5 5 4.62 3.5 3.5  3/8 8 0.81 ¾ 6.62
mm 209.6 38.1 127 117.3 88.9 88.9 9.5 20.6 19.1 168.1
4 in. 10 1.5 6.19 5.75 4.5 3.62 ½ 8 0.81 ¾ 7.88
mm 254 38.1 157.2 146.1 114.3 91.9 12.7 20.6 19.1 200.2
6 in. 12.5 1.5 8.5 8.12 6.63 3.94 ½ 12 0.88 ¾ 10.62
mm 317.5 38.1 215.9 206.2 168.4 100.1 12.7 22.4 19.1 269.7
8 in. 15 1.62 10.62 10.25 8.63 4.38 ½ 12 1  7/8 13
mm 381 41.1 269.7 260.4 219.2 111.3 12.7 25.4 22.2 330.2
10 in. 17.5 1.88 12.75 12.62 10.75 4.62 ½ 16 1.12 1 15.25
mm 444.5 47.8 323.9 320.5 273.1 117.3 12.7 28.4 25.4 387.4
12 in. 20.5 2 15 14.75 12.75 5.12 ½ 16 1.25 1 1/8 17.75
mm 520.7 50.8 381 374.7 323.9 130 12.7 31.8 28.6 450.9
14 in. 23 2.12 16.25 16.75 14 5.62 ½ 20 1.25 1 1/8 20.25
mm 584.2 53.8 412.8 425.5 355.6 142.7 12.7 31.8 28.6 514.4
16 in. 25.5 2.25 18.5 19 16 5.75 ½ 20 1.38 1 ¼ 22.5
mm 647.7 57.2 469.9 482.6 406.4 146.1 12.7 35.1 31.8 571.5
18 in. 28 2.38 21 21 18 6.25 ½ 24 1.38 1 ¼ 24.75
mm 711.2 60.5 533.4 533.4 457.2 158.8 12.7 35.1 31.8 628.7
20 in. 30.5 2.5 23 23.12 20 6.38 ½ 24 1.38 1 ¼ 27
mm 774.7 63.5 584.2 587.2 508 162.1 12.7 35.1 31.8 685.8
24 in. 36 2.75 27.25 27.62 24 6.62 ½ 24 1.62 1 ½ 32
mm 914.4 69.9 692.2 701.5 609.6 168.1 12.7 41.1 38.1 812.8