309/309S Stainless Steel Square Pipe – Comprehensive Product Profile
Product Identity
309/309S Stainless Steel Square Pipe is a heat-resisting austenitic hollow section (22 % Cr / 12–15 % Ni) engineered for continuous service above 550 °C. Grade 309 (UNS S30900) offers maximum creep strength, while 309S (≤0.08 % C) prevents carbide precipitation during welding, eliminating the need for post-weld anneal. Square sizes from 10 × 10 mm to 100 × 100 mm, wall 0.6–6 mm and mill lengths 1–6 m are produced to ASTM A554, EN 10219-2, JIS G3466 and GB/T 3094-2012 in both seamless and welded (HFW, TIG) conditions. All sections are 100 % on-line UT/Eddy-current tested and supplied with EN 10204 3.1/3.2 mill certificates .
Mechanical & Physical Properties
- Yield Strength: 205 MPa min (annealed)
- Tensile Strength: 515 MPa min
- Elongation: 35 % min in 50 mm gauge length
- Hardness: ≤ 217 HB / ≤ 95 HRB
- Density: 7.9 g/cm³
- Modulus of Elasticity: 196 GPa at 20 °C
- The…