Buying Guide
116
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Revised 7/20/2018
Engineering Data
Flange Dimensions
Class 125 Bronze Flange Dimensions
Meets 125 Ib. ASME/ANSI Standard
Dim. A Dim. B Dim. C Dia. No.
Nominal Flange Bolt Thickness Bolt Dia. Bolt
Size O.D. Circle of Flange Hole Bolt Holes
¹⁄₂ 3.50 2.38 .19 .63 .50 4
³⁄₄ 3.88 2.75 .19 .63 .50 4
1 4.25 3.13 .25 .63 .50 4
1¹⁄₄ 4.63 3.50 .25 .63 .50 4
1¹⁄₂ 5.00 3.88 .31 .63 .50 4
2 6.00 4.75 .38 .75 .63 4
2¹⁄₂ 7.00 5.50 .38 .75 .63 4
3 7.50 6.00 .44 .75 .63 4
3¹⁄₂ 8.50 7.00 .44 .75 .63 8
4 9.00 7.50 .44 .75 .63 8
5 10.00 8.50 .44 .88 .75 8
6 11.00 9.50 .50 .88 .75 8
8 13.50 11.75 .63 .88 .75 8
10 16.00 14.25 .63 1.00 .88 12
12 19.00 17.00 .69 1.00 .88 12
Class 150 Bronze Flange Dimensions
Meets ASME/ANSI STD B16.24 and Federal Spec. WW-F-406
Dim. A Dim. B Dim. C Dia. No.
Nominal Flange Bolt Thickness Bolt Dia. Bolt
Size O.D. Circle of Flange Hole Bolt Holes
¹⁄₂ 3.50 2.38 .31 .63 .50 4
³⁄₄ 3.88 2.75 .34 .63 .50 4
1 4.25 3.13 .38 .63 .50 4
1¹⁄₄ 4.63 3.50 .40 .63 .50 4
1¹⁄₂ 5.00 3.88 .44 .63 .50 4
2 6.00 4.75 .50 .75 .63 4
2¹⁄₂ 7.00 5.50 .56 .75 .63 4
3 7.50 6.00 .63 .75 .63 4
3¹⁄₂ 8.50 7.00 .69 .75 .63 8
4 9.00 7.50 .69 .75 .63 8
5 10.00 8.50 .75 .88 .75 8
6 11.00 9.50 .81 .88 .75 8
8 13.50 11.75 .94 .88 .75 8
Corresponding sizes of class 150 (ASME B16.24) flange diameters and drilling templates are the same as those of the American Class 125
Cast Iron Flange Standard (ASME B16.1) and of the American Class 150 Steel Flange Standard (ASME B16.5). Class 300 (ASME B16.24)
flange diameters and drilling templates are the same as those of the American Class 250 Cast Iron Flange Standard (ASME B16.1) and of the
American Class 300 Steel Flange Standard (ASME B16.5).
Full face gaskets extending to the flange face edge as given in American Standard Non-Metal Gaskets for Pipe Flanges ASME B16.21 are
required. Metal gaskets should not be used.
Class 300 Bronze Flange Dimensions
Meets ASME/ANSI STD B16.24
Dim. B Dim. F
Dim. A Min. Dim. C Bolt No.
Nominal Flange Flange Bolt Hole Bolt. of
1
Size Diam. Thickness Circle Diam. Diam. Bolts
¹⁄₂ 3.75 .50 2.63 .63 .50 4
³⁄₄ 4.63 .53 3.25 .75 .63 4
1 4.88 .59 3.50 .75 .63 4
1¹⁄₄ 5.25 .63 3.88 .75 .63 4
1¹⁄₂ 6.13 .69 4.50 .88 .75 4
2 6.50 .75 5.00 .75 .63 8
2¹⁄₂ 7.50 .81 5.88 .88 .75 8
3 8.25 .91 6.63 .88 .75 8
3¹⁄₂ 9.00 .97 7.25 .88 .75 8
4 10.00 1.06 7.88 .88 .75 8
5 11.00 1.13 9.25 .88 .75 8
6 12.50 1.19 10.63 .88 .75 12
8 15.00 1.38 13.00 1.00 .88 12
1
When flanges are integral with fittings or valves, holes for bolts
are drilled to straddle the center line.