Design of Large Size High Pressure Raised Face Flanges to Meet ASME/ANSI B16.5 Standard

ASME/ANSI B16.5 flange design provides the pressure-temperature ratings, materials, design dimensions, tolerances, and testing of pipe flanges in sizes 1/2 through 24 inches. For the most part, ASME/ANSI B16.5 is sufficient for many engineering applications requiring pipe flanges. However, there are instances where the pipe flange required is not covered by the ASME/ANSI Standard. This is particularly true when the flange rating is high, for example, Class 2500, and the flange size is greater than 12 inches. Developing a flange for these cases requires making some extrapolations of the ASME/ANSI design philosophy. In this paper, the process used to develop a Class 2500 14 inch Raised Face flange will be presented and which can be extended to other sizes and pressure classes.