Non-ferrous Metal

ST52/S355JR high precision?cold rolled steel tube for automobile, OD: 10-150mm; WT: 2-25mm

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Cold drawn seamless has closer dimensional tolerances, better surface finish and higher mechanical properties than corresponding grades of hot finished seamless.

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Application:

High Precision Cold Rolled Seamless Steel Tube is used in automotive industry, and in the occasion where the high accuracy, brightness, cleanness of the tube are required.

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Quality Standards:

DIN 2391 Seamless Precison Steel Tubes

BS6323 Specification for Seamless and Welded Steel Tubes for Automobile, Mechanical and General Engineering Purposes

ASTM A519 Standard Specification for Seamless Carbon and Alloy Steel Mechanical Tubing

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Steel Grades:

DIN Standard: St35, St52
BS Standard: CFS 4, CFS 5, CFS 10
ASTM Standard: 1020, 1045, 4130

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Size Range:

Outer Diameter: 10-150 mm

Wall Thickness: 2-25 mm

Length Random Length, Fixed Length, etc.

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Dimension tolerance:

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I.D tolerance (mm) | O.D tolerance (mm) | I.D Roughness (μm) | Straightness (mm/meter) |
H7-H9 | -/+0.5% | 0.10-0.80 | 0.2-0.80 |
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Chemical composition(%):

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Grade | C | Si | Mn | P | S | Cr | Mo |
ST35 | 0.17 max | 0.35 max | 0.40 max | 0.025 max | 0.025 max | / | / |
ST42 | 0.21 max | 0.35 max | 0.40 max | 0.025 max | 0.025 max | / | / |
ST52 (DIN1.0580) | 0.22 max | 0.55 max | 1.60 max | 0.025 max | 0.025 max | / | / |
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Delivery Conditions:

+C (BK) Hard. No final treatment after final cold rolling.
+LC (BKW) Soft. Final heat treatment is followed by a suitable drawing pass (limited reduction of area).
+SR (BKS) Stress Relieved. After final cold rolling, the tubes are stress relieved in a controlled atmosphere.
+A (GBK) Annealed. After final cold rolling, the tubes are annealed in a controlled atmosphere.
+N (NBK) Normalized. After final cold rolling, the tubes are normalized in a controlled atmosphere.

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Mechanical Properties( T=20°C if not differently stated ):

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Grades | Delivery Conditions | Tensile Strength Rm (Mpa) | Yield Strength R2 (Mpa) | Elongation in the longitudinal direction Al (%) |
St 52 | +C (BK) | 640 min | / | 4 min |
St 52 | +LC (BKW) | 580 min | / | 7 min |
St 52 | +SR (BKS) | 580 min | 420 min | 10 min |
St 52 | +A (GBK) | 490 min | / | 22 min |
St 52 | +N (NBK) | 490-630 | 355 min | 22 min |
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Our Services

Third Party inspection acceptable. such as SGS, BV etc.

Supplying financial support with usance L/C 180 days after B/L date.

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Please feel free to contact us again if you have any further questions. We look forward to receiving an order from you.