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

ANSI 2500-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 4-3/4 4-3/4 R13
3/4 3/4 4 4-3/4 5 R16
1 7/8 4 5-1/4 5-1/2 R18
1-1/4 1 4 6 6 R21
1-1/2 1-1/8 4 6-1/2 6-3/4 R23
2 1 8 6-3/4 7 R26
2-1/2 1-1/8 8 7-3/4 8 R28
3 1-1/4 8 8-1/2 9 R32
4 1-1/2 8 9-3/4 10-1/4 R38
5 1-3/4 8 11-3/4 12-1/4 R42
6 2 8 13-1/2 14 R47
8 2 12 15 15-1/2 R51
10 2-1/2 12 19 20 R55
12 2-3/4 12 21 22 R60