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

ANSI 900-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
37/885-1/25-3/4R31
41-1/886-1/26-3/4R37
51-1/487-1/27-1/2R41
61-1/8127-1/27-3/4R45
81-3/8128-1/28-3/4R49
101-3/81699-1/4R53
121-3/8209-3/410R57
141-1/22010-1/211R62
161-5/8201111-1/2R66
181-7/82012-3/413-1/4R70
2022013-1/214-1/4R74
242-1/2201718R78