DIN 1629 ST37 Carbon Steel Pipes: Precision Cold-Rolled Tubes for Structural & Automotive Applications.
Cold-Rolled Seamless & Welded Pipes (10–762mm OD, 1–100mm WT) with ±1% Dimensional Accuracy.
Manufactured to DIN 1629, EN 10219, and ASTM A500 standards, ST37 carbon steel pipes deliver 235–255 MPa yield strength for high-precision stamping and structural frameworks. Available in 3–12m lengths (custom-cut) with polished, machined, or black surfaces, these pipes achieve ±0.2mm thickness consistency via cold-rolling, ideal for applications requiring tight tolerances.
Key Features:
- Surface Finish: Ra ≤3.2µm (polished), suitable for direct painting or galvanizing.
- Formability: 25–30% elongation (EN 10002), enabling complex bends without cracking.
- Certifications: CE Marking, ISO 9001:2015, RoHS Compliance.
Technical Specifications
Dimensional Tolerances
| Parameter | Tolerance | Standard |
|---|---|---|
| Outer Diameter | ±1% | DIN 1629 Pt.3 |
| Wall Thickness | ±5% | EN 10219 |
| Ovality | ≤1.5% OD | ASTM A500 |
Mechanical Properties (Cold-Rolled ST37)
| Yield Strength | Tensile Strength | Elongation | Hardness | Flatness |
|---|---|---|---|---|
| 235–255 MPa | 360–510 MPa | ≥25% | 70–80 HRB | ≤0.5mm/m |
Material Composition & Manufacturing
Chemical Analysis (DIN 1629 ST37)
| Element | C ≤ | Mn ≤ | P ≤ | S ≤ | Al ≥ |
|---|---|---|---|---|---|
| Content | 0.17% | 0.60% | 0.040% | 0.040% | 0.020% |
Production Process:
- Cold Rolling: Reduces thickness by 50–80% for enhanced surface finish (±0.1mm tolerance).
- Stress Relieving: Annealed at 650°C (1,202°F) to eliminate work hardening.
- Testing: Eddy current (EN 10246-3) and tensile testing per EN 10002.
Applications & Performance
- Automotive Chassis:
- 76mm OD, 3mm WT: High-straightness tubes for suspension systems (ISO 3574).
- Furniture Frames:
- 25mm OD, 1.5mm WT: Burr-free edges for welded chair bases (JIS G3444).
- HVAC Ducts:
- 304mm OD, 2mm WT: Seamless airflow conduits with Ra 1.6µm finish.
Advantages vs. Competitors:
- Stamping Efficiency: 40% lower tool wear vs. hot-rolled steel.
- Weldability: No pre-heat required for MIG/TIG welding (AWS D1.1).
Quality Assurance & Packaging
- Non-Destructive Testing:
- Ultrasonic Testing: Detects ≥0.5mm flaws (EN 10246-1).
- Hardness Mapping: 10-point Vickers test per batch.
- Surface Protection:
- VCI paper + oil coating (DIN 50968) for 12-month rust prevention.
- Export Packaging:
- Hexagonal bundles with corner guards (max 2.5 tons).
Packing And Delivery
