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

ANSI 1500-lb Flanges

Nominal Pipe SizeDiameter of StudsNo.
Of
Studs
Stud Bolt LengthRing
Joint Gasket No.
Raised FaceRing Joint
InchesInchesInchesInches
1/23/4444-1/4R12
3/43/444-1/44-1/2R14
17/844-3/45R16
1-1/47/8455R18
1-1/2145-1/45-1/2R20
27/885-1/25-3/4R24
2-1/2186-1/46-1/4R27
31-1/886-3/47R35
41-1/487-1/27-3/4R39
51-1/289-3/49-3/4R44
61-3/8121010-1/2R46
81-5/81211-1/411-3/4R50
101-7/81213-1/413-1/2R54
1221614-3/415-1/4R58
142-1/4161616-3/4R63
162-1/21617-1/218-1/2R67
182-3/41619-1/420-1/4R71
203162122-1/4R75
243-1/2162425-1/2R79