| Structure with a seamless series standard GB / T8162-2008, ISO2937, ASTM A53, ASTM A192, ASTM A106. JIS G 3441, BS EN 10210-1, DIN 1629-1984, ISO 559: 1991. use: Including the use for general structural and mechanical structure, a large variety of structural pipe for construction, machinery, transportation, aviation, oil exploration and other industries Dimensional tolerances | standard | Diameter tolerance | ` Walled tolerance | | GB / T 8162 | D (50 | ± 0.50mm | S (4mm | ±12.5% | | D≥50 | ±1% | 4-20mm | +15/ -12.5% | | S≥20mm | ±12.5% | | DIN1629 | D50 | ± 0.50mm | S2Sn | +15/ -10% | | D48.3D48.3 | ±1% | 2SnS4Sn | +12.5/ -10% | | S4Sn | ±9% | | ASTM A53 | D (48.3 | ± 0.4 / -0.79mm | ±12.5% | | D≥48.3 | ±1% | | ASTM A106 | D (48.3 | ± 0.4 / -0.79mm | ±12.5% | | D48.3-114.3 | ± 0.79mm | | D≥114.3 | ± 1.59 / -0.79mm | Mechanical Properties | standard | Steel grade | Tensile strength (MPa) | Yield strength (MPa) | Elongation | | (16mm | 16-30mm | | GB / T 8162 | 10 | 335-475 | 205 | 195 | 24 | | 20 | 390 | 245 | 235 | 20 | | 35 | 510 | 305 | 295 | 17 | | 45 | 590 | 335 | 325 | 14 | | 16Mn | 490 | 325 | 315 | 21 | | DIN 1629 | | (16mm | ) 16mm | | | ST35 | 345-460 | 235 | 225 | 25 | | ST45 | 440-550 | 255 | 245 | 21 | | ST55 | 540-645 | 295 | 285 | 17 | | ST52 | 490-630 | 355 | 345 | 22 | | ST45 | 590-730 | 335 | 325 | 14 | | ASTM A53 | A | 330 | 205 | | | B | 415 | 240 | | ASTM A106 | A | 330 | 205 | | | B | 415 | 240 | | C | 485 | 275 | chemical composition (%) : | standard | Trademark | C | Si | Mn | P≤ | S≤ | Cu≤ | Ni≤ | Cr≤ | Mo≤ | V≤ | | GB / T 8162 | 10 | 0.07-0.14 | 0.17-0.37 | 0.35-0.65 | 0.035 | 0.035 | 0.25 | 0.25 | 0.15 | / | / | | 20 | 0.17-0.24 | 0.17-0.37 | 0.35-0.65 | 0.035 | 0.035 | 0.25 | 0.25 | 0.25 | / | / | | 35 | 0.32-0.39 | 0.17-0.37 | 0.50-0.80 | 0.035 | 0.035 | 0.25 | 0.25 | 0.25 | / | / | | 45 | 0.42-0.50 | 0.17-0.37 | 0.50-0.80 | 0.035 | 0.035 | 0.25 | 0.30 | 0.25 | / | / | | 16Mn | 0.12-0.20 | 0.20-0.55 | 1.20-1.60 | 0.045 | 0.045 | 0.25 | 0.25 | 0.25 | / | / | | DIN 1629 | St35 | ≤0.18 | 0.15-0.35 | 0.35-0.65 | 0.035 | 0.035 | 0.25 | 0.25 | 0.25 | / | / | | St45 | ≤0.25 | 0.15-0.35 | 0.50-0.80 | 0.035 | 0.035 | 0.25 | 0.25 | 0.25 | / | / | | St55 | 0.33-0.41 | 0.15-0.35 | 0.50-0.80 | 0.035 | 0.035 | 0.25 | 0.25 | 0.25 | / | / | | St52 | ≤0.20 | ≤0.55 | ≤1.50 | 0.035 | 0.035 | 0.25 | 0.25 | 0.25 | / | / | | ASTM A53 | CK45 | 0.42-0.50 | 0.17-0.37 | 0.50-0.80 | 0.035 | 0.035 | 0.25 | 0.25 | 0.25 | / | / | | ASTM A106 | A | ≤0.25 | / | ≤0.95 | 0.05 | 0.045 | 0.40 | 0.40 | 0.40 | 0.15 | 0.08 | | B | ≤0.30 | / | ≤1.20 | 0.05 | 0.06 | 0.40 | 0.40 | 0.40 | 0.15 | 0.08 | | A | ≤0.25 | ≥0.10 | 0.27-0.93 | 0.035 | 0.035 | 0.40 | 0.40 | 0.40 | 0.15 | 0.08 | | B | ≤0.30 | ≥0.10 | 0.29-1.06 | 0.035 | 0.035 | 0.40 | 0.40 | 0.40 | 0.15 | 0.08 | | C | ≤0.35 | ≥0.10 | 0.29-1.06 | 0.035 | 0.035 | 0.40 | 0.40 | 0.40 | 0.15 | 0.08 | | |
