ASTM A694 F42 Flanges: Chemical Composition and Mechanical Properties

In high-pressure oil & gas transmission pipeline, the ASTM A694 F42 flanges are designated to connect with line pipes of API 5L Grade X42(L290) as well as high-yield butt-welding elbows, bends and tees in ASTM A860 WPHY42 material. All of these piping components have exactly the same minimum requirements for yield strength and tensile strength. The ASTM A694 F42 flanges are often furnished in larger sizes(from 12" to 60") in accordance with MSS SP 44 or ASME B16.47 Series A and Series B.

ASTM A694 F42 flanges WN RF 42" 150# STD ASME B16.47 Series B

ASTM A694 F42 flanges WN RF 36" 150# XS ASME B16.47 Series A

Unlike the low alloy steel ASTM A695 F65 or ASTM A694 F70, ASTM A694 Gr.F42 can be furnished as carbon steel material. There is another regular carbon steel material, ASTM A105, endorsed by ASME B16.5 and ASME B16.47. Although the actual chemical composition of most A105 flanges falls in the required range of ASTM A694 F42, they are not interchangeable. Since the actual yield strength of A105 forgings is around 275 MPa  which is less than the minimum requirement of F42(290 MPa). Usually ASTM A105 forged flanges are designated to connect with seamless pipes of ASTM A106 Gr.B and ASTM A53 Gr.B.

Chemical requirements for ASTM A694 F42 flanges