1. Material Composition & Key Properties
Q: What are the chemical and mechanical properties of E235 steel?
A:
Chemical Composition (wt%):
C: ≤0.17 | Mn: 0.40–1.20 | P: ≤0.030 | S: ≤0.025.
Mechanical Properties:
Yield Strength (σᵧ): ≥235 MPa | Tensile Strength (σₜ): 360–510 MPa.
Elongation (A₅): ≥25% | Hardness: ≤140 HB.
Note: E235 is a non-alloy steel with excellent weldability (Ceq ≤0.36).
2. Manufacturing Standards & Processes
Q: How are EN 10297-1 E235 tubes produced?
A:
Process: Seamless (hot-finished or cold-drawn) or welded (ERW/SAW).
Heat Treatment: Normalized or stress-relieved (per EN 10297-1).
Key Standard: EN 10297-1 (Seamless circular steel tubes for mechanical/engineering purposes).
3. Dimensional Tolerances
Q: What tolerances apply to these tubes?
A:
| Parameter | Tolerance (EN 10297-1) |
|---|---|
| OD (D) | ±1.0% (min ±0.5 mm) |
| Wall Thickness | ±10% (min ±0.3 mm) |
| Straightness | ≤1.5 mm/m |
4. Applications & Suitability
Q: Where is E235 typically used?
A:
General Engineering: Hydraulic cylinders, structural components.
Automotive: Chassis parts, exhaust systems (cold-drawn).
Low-Pressure Fluid Transport: Water/gas pipelines (welded variants).
Avoid: High-temperature (>350°C) or corrosive environments (use alloy/stainless steels).
5. Quality Control & Certifications
Q: How is quality validated?
A:
Testing: Tensile (EN ISO 6892-1), hardness (EN ISO 6506-1), hydrostatic (optional).
Certification: EN 10204 3.1/3.2 mill certificates, PED 2014/68/EU for pressure applications.
NDT: Ultrasonic (EN 10246-1) or eddy current (EN 10246-2) for defect detection.
