1. Material Composition & Key Properties
Q: What defines the chemical/mechanical properties of E470 steel?
A:
Chemical (wt%):
C: ≤0.22 | Mn: 1.00–1.70 | P: ≤0.020 | S: ≤0.015 | Si: ≤0.60.
Mechanical:
Yield Strength (σᵧ): ≥470 MPa | Tensile (σₜ): 570–720 MPa.
Elongation (A₅): ≥16% | Hardness: ≤200 HB.
Note: E470 is a high-strength microalloyed steel with limited weldability (Ceq ≤0.50).
2. Manufacturing & Standards
Q: How are these tubes produced and certified?
A:
Process: Exclusively seamless (hot-rolled + cold-drawn for precision).
Heat Treatment: Quenching & tempering (Q&T) mandatory (EN 10297-1 §6.3).
Standard Scope: High-stress mechanical/structural applications.
3. Dimensional Tolerances
Q: What tolerances apply to E470 tubes?
A:
| Parameter | Tolerance | Criticality |
|---|---|---|
| OD | ±0.8% (min ±0.4 mm) | Critical for press fits |
| Wall Thickness | ±8% (min ±0.3 mm) | Affects fatigue resistance |
| Straightness | ≤1.2 mm/m | Essential for rotating parts |
4. Applications & Limitations
Q: Where is E470 typically used?
A:
Heavy Industry: Hydraulic rams (>500 bar), mining drill rods.
Energy: Wind turbine shafts, oil/gas umbilicals.
Avoid:
Temperatures >550°C (risk of temper embrittlement).
Uncoated use in chloride-rich environments.
5. Quality Validation
Q: How is quality assured?
A:
Mandatory Tests:
Tensile (EN ISO 6892-1) | Impact (ISO 148-1 at -20°C).
NDT: 100% ultrasonic (EN 10246-1) + magnetic particle (ISO 10893-8).
Certifications: EN 10204 3.2 | PED 2014/68/EU (Category IV).
