Adopted by a Conference of Manufacturers, June 28, 1901.
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Size of|Diam. of|Thickness |Diameter of |Number of|Size of
Pipe. |Flange. |of Flange.|Bolt Circle.|Bolts. |Bolts.
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Inches.|Inches. | Inches. | Inches. | |Inches.
2 | 6-1/2 | 7/8 | 5 | 4 | 5/8
2-1/2| 7-1/2 | 1 | 5-7/8 | 4 | 3/4
3 | 8-1/4 | 1-1/8 | 6-5/8 | 8 | 5/8
3-1/2| 9 | 1-3/16 | 7-1/4 | 8 | 5/8
4 | 10 | 1-1/4 | 7-7/8 | 8 | 3/4
4-1/2| 10-1/2 | 1-5/16 | 8-1/2 | 8 | 3/4
5 | 11 | 1-3/8 | 9-1/4 | 8 | 3/4
6 | 12-1/2 | 1-7/16 | 10-5/8 | 12 | 3/4
7 | 14 | 1-1/2 | 11-7/8 | 12 | 7/8
8 | 15 | 1-5/8 | 13 | 12 | 7/8
9 | 16 | 1-3/4 | 14 | 12 | 7/8
10 | 17-1/2 | 1-7/8 | 15-1/4 | 16 | 7/8
12 | 20 | 2 | 17-3/4 | 16 | 7/8
14 | 22-1/2 | 2-1/8 | 20 | 20 | 7/8
15 | 23-1/2 | 2-3/16 | 21 | 20 |1
16 | 25 | 2-1/4 | 22-1/2 | 20 |1
18 | 27 | 2-3/8 | 24-1/2 | 24 |1
20 | 29-1/2 | 2-1/2 | 26-3/4 | 24 |1-1/8
22 | 31-1/2 | 2-5/8 | 28-3/4 | 28 |1-1/8
24 | 34 | 2-3/4 | 31-1/4 | 28 |1-1/8
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