Advantages: Produced for drilling with uniform wall-thickness, wall thickness deviation +/-5%. High dimensional accuracy and nice straightness, straightness 1/1000mm or 0.5/1000mm. Reliable performance (including hardness) and nice torsion-resistant. Main standards: ASTM A519, DIN. Main materials: 4130, 4135 and 4140. O.D. 30 to 127mm, W.T. 5 to 13mm For QT condition: Tensile strength>=1030Mpa, Yield strength: >=950Mpa, Elongation: >=13%, HRC 30 to 32. Zhejiang Dingxin Steel Tube Manufacturing Co., Ltd. ISO9001, TS16949. Contact person: Lisa Hsu, sales04[at]dingxintube[dot]cn Mobile:+86-15669301195
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