*For thicker flanges, see ASME B16.9

Bevel Wall Thickness (t) 0.19 In. To 0.88 In. Inclusive

A = Outside Diameter of flange and mating pipe (inches)
B = Inside Diameter of flange (inches)
t = Wall thickness of flange hub at bevel (inches)

The recommendations that follow apply to weld neck flanges with standard plain end bevels (as shown above) and with a hub thickness at the bevel no greater than 1 1/2 times the mating pipe thickness.

1. The thickness of the flange hub at the weld bevel and the pipe shall be in accordance with the design requirements of the applicable section of ASME B31 Code for Pressure Piping.
2. When the internal offset due to unequal thickness does not exceed 1/2 times the pipe wall thickness, then the rules and figures given on page 75 are recommended as well for joining weld neck flanges to pipe of lesser wall and/or higher strength.
3. When the additional thickness of the hub at the bevel results in an offset at the outside diameters of the ends to be joined, reference should be made to ASME B31 and ASME B16.5

Next >