ASTM A789
Seamless and welded duplex stainless steel tubing
Covers seamless and welded duplex and super duplex stainless steel tubing for general corrosive service, with an emphasis on stress-corrosion-cracking resistance.
- Pipe & tube
- ASME SA-789
- 3 grades in stock range
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What to know before ordering to ASTM A789
The points that decide whether material to ASTM A789 is accepted at inspection.
- Tubing is ordered by OD and wall thickness, not by NPS and schedule.
- Heat-exchanger and instrumentation tubing in 2205 and 2507 is typically bought to A789.
- Pipe in the same grades is ASTM A790.
Grades and products we supply to ASTM A789
| Grade | Product | Designation on the certificate |
|---|---|---|
| Duplex 2205 | Pipe & Tube | ASTM A789 |
| Super Duplex 2507 | Pipe & Tube | ASTM A789 |
| Super Duplex S32760 | Pipe & Tube | ASTM A789 |
How ASTM A789 fits into an order
A purchase order line is only complete when it names the material standard, the dimensional standard and the inspection document. Miss one and the mill, the inspector and the buyer can each read the order differently.
Related standards
ASTM A789 — questions buyers ask
What does ASTM A789 cover?
Covers seamless and welded duplex and super duplex stainless steel tubing for general corrosive service, with an emphasis on stress-corrosion-cracking resistance.
Which grades do you supply to ASTM A789?
Duplex 2205, Super Duplex 2507, Super Duplex S32760 — see the table on this page for the exact product and designation.
What is the difference between ASTM A789 and ASME SA-789?
ASME SA-789 is the ASME Boiler and Pressure Vessel Code (Section II) adoption of ASTM A789. The technical requirements are usually identical to a specific ASTM edition; pressure-equipment codes call for the ASME designation, and most mill certificates show both.
Do you supply certificates to this standard?
Yes. Material is supplied with mill test certificates to EN 10204 3.1 showing the standard, grade and heat number; 3.2 with third-party inspection on request.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026