Group 1.1 Pressure-Temperature Ratings

The standard carbon steel group and by far the most common material in B16.5 flanges. A105 forged carbon steel sits here.

Standard
ASME B16.5
Group
Group 1.1
Materials
A105, A216 WCB, A515 Gr 70, A516 Gr 70, A350 LF2 (as forged)
Class 150 at 100 °F
285 psig (19.7 bar)
Class 150 at 600 °F
140 psig (9.7 bar)
ASME B16.5 pressure-temperature ratings for Group 1.1 materials, in psig.
Class100 °F200 °F300 °F400 °F500 °F600 °F650 °F700 °F750 °F800 °F850 °F900 °F950 °F1000 °F
Class 150285260230200170140125110958065503520
Class 30074068065563560557055053050541027017010550
Class 40099090087584580575573071067555035523014070
Class 600148013501315127012051135110010651015825535345205105
Class 9002220202519701900181017051650160015201235805515310155
Class 150037053375328031703015284027452665253520551340860515260
Class 2500617056255470528050254730457544404230343022301430860430

Interpolation between listed temperatures is permitted; extrapolation is not.

Common questions

Which materials are in ASME B16.5 Group 1.1?

A105, A216 WCB, A515 Gr 70, A516 Gr 70, A350 LF2 (as forged).

What is a Class 300 Group 1.1 flange rated at 600 °F?

570 psig (39.3 bar). At 100 °F the same flange is rated 740 psig (51.0 bar).

Other material groups