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Raised Face Height

For the height measures H and B of all described dimensions of flanges on this website, with exception of the Lap Joint Flange, it is important to understand and remember the following:

In Pressure Classes 150 and 300, the height of raised face is approximately 1.6 mm (1/16 inch).
In these two Pressure Classes, almost all suppliers of flanges, show in their catalog or brochure, the H and B dimensions including the raised face height. See figure 1 on the image below.

Raised face height

In Pressure Classes 400, 600, 900, 1500 & 2500, the height of raised face is approximately 6.4 mm (1/4 inch). In these Pressure Classes, most suppliers show the H and B dimensions excluding the raised face height. See figure 2 on the image above.

On this website you will find two dimensions. The top row dimensions are excluding the raised face height, and in the bottom row the dimensions are including the raised face height.

Dimensions Socket Weld Flanges & Stud Bolts ASME B16.5
Socket Weld flange

Notes:

Measuring lengths of Stud Bolts and Hex bolts

Dimensional Tolerances of Socket Weld Flanges ASME B16.5