Stainless Steel 309/1.4828/S30900 and 309S/1.4833/S30908 are often used for high temperature applications. Their high chromium and nickel content allow them have excellent performance on resistance to oxidation and heat resistance in both room and elevated temperature. Comparing with SS 304, it shows more resistant to marine atmospheres. And the most significant difference between 309 and 309S is the carbon content. Alloy 309S has a much less carbon composition which minimizes carbide precipitation and improves weldability.
ASTM A312 is for seamless.welded and heavily cold worked austenitic stainless steel pipe, which provide the the tolerance for SS309/309S of the pipe product(Reference document-ASTM A999)
|Steel Grade||300 Series, 309,309S,309H||Type||Seamless, Straight-Seam Welded, Heavily Cold Worked|
|Standard||ASTM, AISI, GB, DIN, JIS||Certification||ISO,SGS,BV,ISO/CE/SGS|
|Technique||Cold Rolled, Cold Drawn||Min./Avg.||Avg.|
|Outer Diameter||12.7-3600mm, Customized||Finish||Brush Polish Cold Drawn, Pickled, Bright Annealed|