Flange Pressure and Temperature Ratings, B16.5

Written by Matt Milbury. Posted in Pipe Flanges

The following table is the maximum allowable non-shock pressure and temperature ratings for various flanges:

ANSI Class15030040060090015002500
Temperature oFMaximum Allowable Non-Shock Pressure PSIG
-20 to 100 285 740 985 1480 2220 3705 6170
200 260 680 905 1360 2035 3395 5655
300 230 655 870 1310 1965 3270 5450
400 200 635 845 1265 1900 3170 5280
500 170 605 805 1205 1810 3015 5025
600 140 570 755 1135 1705 2840 4730
650 125 550 730 1100 1650 2745 4575
700 110 530 710 1060 1590 2655 4425
750 95 505 675 1015 1520 2535 4230
800 80 410 550 825 1235 2055 3430
850 65 320 425 535 640 955 2655
900 50 230 305 460 690 1150 1915
950 35 135 185 275 410 685 1145
1000 20 85 115 170 255 430 715
  • This table is in accordance with ANSI B16.5 (2003) maximum allowable non-shock pressure (psig) and temperature ratings for Group 1.1 Materials. There are several notes associated with this, and other tables in ASME B16.5 that need to be verified by the engineer prior to specification. For example, A105 is permitted for use over 800°F but not recommended.
  • Based on American Society of Mechanical Engineers - ASME B16.5