Covers pressure-temperature ratings, materials, dimensions, tolerances, marking, and testing for pipe flanges in sizes NPS 26 through NPS 60. Included here are flanges with rating class designations 75, 150, 300, 400, 600, and 900 with requirements given in both SI (metric) and U.S. Customary units, with diameter of bolts and flange bolt holes expressed in inch units.
ANSI/ASME B16.47-2011 history
2011ANSI/ASME B16.47-2011 Large Diameter Steel Flanges - NPS 26 Through NPS 60 Metric/Inch Standard