Bolting Dimensions for API Flanges

3000 lb. W.P.

Nominal Size InchesGasket API NumberNumber Of StudsStud Bolt Size Inches
3-1/8R3187/8 X 6
4-1/16R3781-1/8 X 7
5-1/8R4181-1/4 X 7-3/4
7-1/16R45121-1/8 X 8
9R49121-3/8 X 9
11R53161-3/8 X 9-1/2
13-5/8R57201-3/8 X 10-1/4
16-3/4R66201-5/8 X 11-3/4
20-3/4R74202 X 14-1/2
26-3/4BX168242 X 17