Astm A790 / A789 UNS S31803 Duplex Pipe Tube

ASTM A790 Uns S31803 duplex pipe tube is duplex stainless steel pipe and a medium alloy duplex stainless steel with good chloride stress resistance. Medium alloy type – the representative grade is UNS S31803 (22Cr-5Ni-3Mo-0.15N); S31803 duplex steel pipe is in three kinds of dual phase steel (2205 duplex stainless steel pipe, 2507 duplex stainless steel pipe, S31803 duplex stainless steel seamless tube) is the most widely used.

Scope of application

1.1x00a0;This specification2 covers seamless and straight-seam welded ferritic/austenitic steel pipe intended for general corrosive service, with particular emphasis on resistance to stress corrosion cracking. These steels are susceptible to embrittlement if used for prolonged periods at elevated temperatures.

1.2x00a0;Optional supplementary requirements are provided for pipe when a greater degree of testing is desired. These supplementary requirements call for additional tests to be made and, when desired, one or more of these may be specified in the order.

1.3x00a0;Appendix X1 of this specification lists the dimensions of welded and seamless stainless steel pipe as shown in ANSI B36.19. Pipe having other dimensions may be furnished provided such pipe complies with all other requirements of this specification.

1.4x00a0;The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. The inch-pound units shall apply unless the M designation of this specification is specified in the order.

ASTM A790 UNS S31803 Pipe & tube is a duplex stainless steel. 22% chromium duplex ( austenitic/ferritic ) steel ( type 2205 / UNS S32205 ) with moderate to high strength and good resistance to common corrosion/stress, corrosion/cracking.

The alloy of ASTM A790 UNS S31803 Pipe & tube is resistant to chloride environments and sulfide stress corrosion and is approximately twice as strong as standard austenitic stainless steels. This alloy can be successfully used as a replacement for 300 series austenitic stainless steels when higher mechanical strength/lower weight is required. The F51 is easy to weld with many standard arc welding equipment, but is not recommended for oxy-ethylene block welding due to the potential for carburization of the weld metal.