Bolting Dimensions for ANSI Flanges all sizes as per ANSI B16.5-1988

ANSI 1500-lb Flanges

Nominal Pipe Size Diameter of Studs No.
Of
Studs
Stud Bolt Length Ring
Joint Gasket No.
Raised Face Ring Joint
Inches Inches Inches Inches
1/2 3/4 4 4 4-1/4 R12
3/4 3/4 4 4-1/4 4-1/2 R14
1 7/8 4 4-3/4 5 R16
1-1/4 7/8 4 5 5 R18
1-1/2 1 4 5-1/4 5-1/2 R20
2 7/8 8 5-1/2 5-3/4 R24
2-1/2 1 8 6-1/4 6-1/4 R27
3 1-1/8 8 6-3/4 7 R35
4 1-1/4 8 7-1/2 7-3/4 R39
5 1-1/2 8 9-3/4 9-3/4 R44
6 1-3/8 12 10 10-1/2 R46
8 1-5/8 12 11-1/4 11-3/4 R50
10 1-7/8 12 13-1/4 13-1/2 R54
12 2 16 14-3/4 15-1/4 R58
14 2-1/4 16 16 16-3/4 R63
16 2-1/2 16 17-1/2 18-1/2 R67
18 2-3/4 16 19-1/4 20-1/4 R71
20 3 16 21 22-1/4 R75
24 3-1/2 16 24 25-1/2 R79