ASTM A790 UNS S31803 Seamless Pipe/Tube

-Engineering Guide for High-Strength and Corrosion-Resistant Duplex Piping

Discover ASTM A790 UNS S31803 seamless pipe benefits. Learn selection tips for desalination & oil gas projects with MTSCO's reliable duplex solutions.

ASTM A790 specifies the key requirements for seamless/welded duplex stainless steel pipes. This article focuses on UNS S31803 (2205 duplex stainless steel) seamless pipes, providing engineering and procurement with a readily implementable selection and acceptance framework.

What are ASTM A790 and S31803?

ASTM A790: Covers duplex stainless steel pipes (seamless and welded) for piping systems requiring high corrosion resistance, pressure resistance, and structural reliability.

UNS S31803: Commonly referred to in engineering as 2205 duplex stainless steel, it has an austenitic + ferritic microstructure, balancing strength and resistance to chloride corrosion.

Typical Application Scenarios

ASTM A790 UNS S31803 Seamless Pipes offer high yield strength, stable resistance to pitting/crevice corrosion, and strong resistance to stress corrosion cracking (SCC). They are primarily used in the following key areas:

Desalination & Marine Engineering: main pipelines and heat exchange system piping.

Oil & Gas / Chemical Processing: processes containing chlorine and CO₂/H₂S (whether acidic conditions are met needs to be assessed according to project specifications, such as NACE MR0175/ISO 15156).

Pulp & Paper / Hydrometallurgy: transportation of chloride-containing and corrosive slurries.

Selection and Procurement Considerations

Clearly define delivery condition and dimensional tolerances

Control chemical composition and phase ratio

Acceptance and Inspection:

PMI+ dimensional and appearance testing

UT/ET and other non-destructive testing and hydrostatic testing

MTSCO, leveraging its integrated factory network, can provide UNS S31803 Seamless Pipes conforming to ASTM A790 standards. Pipes ensures product compliance and stability through deep collaboration with partner factories boasting 35 years of manufacturing experience and triple quality control. It also provides customized solutions from professional engineers, helping customers efficiently select and apply products.