Q620FTD Ultra‑High Strength Wind Power Steel
GB/T 28410-2012 | 620MPa Grade | -20°C Impact (47J) for heavy‑duty wind turbines
Product Overview
This article introduces Q620FTD structural steel for wind turbine towers manufactured by Chinese steel mills, hoping to meet your needs and encourage you to purchase this grade of steel. Q620FTD is a high‑strength low‑alloy steel plate offering minimum yield strength of 620 MPa (≤16mm), excellent toughness at -20°C (Grade D, 47J), and complies with GB/T 28410‑2012 for wind tower construction in demanding environments requiring ultra‑high load capacity.
📊 Q620FTD Approximate Grade Lookup Table
Key Advantages
- 620MPa Ultra‑High Strength: Minimum yield 620 MPa (≤40mm) for next‑generation large wind turbines and heavy‑load tower designs.
- Enhanced -20°C Impact Toughness: Minimum 47J at -20°C (Grade D) – superior reliability for cold climate zones.
- Optimized Alloy Design: Controlled micro‑alloying (Nb, V, Ti) plus Mo, Cr, Ni for excellent strength and weldability.
- Low Impurity Content: P≤0.020, S≤0.010 for improved low‑temperature performance and cleanliness.
- Weldable Fine‑Grain Steel: Low carbon equivalent design suitable for field welding of tower sections.
Technical Specifications
Q620FTD Chemical Composition (GB/T 28410-2012, mass fraction %)
| Element | Q620FT D (max or range) |
|---|---|
| Grade | Q620FT D |
| C (max) | 0.20 |
| Mn | ≤1.80 (lower limit for normalized*) |
| P (max) | 0.020 |
| S (max) | 0.010 |
| Si (max) | 0.60 |
| Nb (max) | 0.070 |
| V (max) | 0.15 |
| Ti (max) | 0.050 |
| Mo (max) | 0.50 |
| Cr (max) | 0.80 |
| Ni (max) | 0.80 |
| Cu (max) | 0.55 |
| Als (min) | 0.015 |
| N (max) | 0.012 |
Q620FTD Mechanical Properties (GB/T 28410-2012)
| Property / Thickness | Q620FT D Value |
|---|---|
| Yield ReL (MPa) min ≤16mm | 620 |
| Yield ReL (MPa) min >16~40mm | 620 |
| Yield ReL (MPa) min >40~100mm | 600 |
| Tensile Rm (MPa) | 710 ~ 880 |
| Elongation A (%) min | 15 |
| Impact KV2 (J) min at -20°C | 47 |
| 180° Bending ≤16mm | d=2a |
| 180° Bending >16~100mm | d=3a |
Q620FTD Size & Specification
| Parameter | Plate (mm) | Coil (mm) |
|---|---|---|
| Thickness | 8 - 100 (up to 120) | 2.0 - 12.0 |
| Width | 1500 - 5300 | 900 - 2000 |
| Length / Coil ID | 6000 - 12000 | ID 508 / 610 |
| Delivery Condition | Normalized, TMCP, Quenched + Tempered (QT) upon request | |
Quality & Manufacturing Assurance
Modern Production
Advanced continuous casting and controlled rolling for ultra‑high strength
In-process Inspection
Spectral analysis, UT testing, -20°C impact verification
Full Documentation
MTC EN 10204 3.1/3.2 with 620MPa grade results
Packaging & Logistics
- Standard Packaging: Steel plates bundled with steel straps on wooden skids. Coils wrapped with waterproof paper.
- Marking: Grade, size, heat number, weight clearly marked.
- Logistics: FOB, CIF, CFR from main Chinese ports.
- Lead Time: 28-38 days after order confirmation (depending on QT requirement).
Request a Quotation
Interested in Q620FTD ultra‑high strength steel for next‑gen wind towers? Fill out the form below. We'll reply within 12 hours.
This form uses Formspree. Your information will be sent securely.
Other Wind Power Steel Grades
Explore our full range of wind energy steels for various strength and climate requirements:
|
Q620FTE
-40°C Impact
|
Q690FTD
-20°C Impact
|
Q550FTD
-20°C Impact
|
Frequently Asked Questions
What is the advantage of Q620FTD over Q550FTD?
Q620FTD provides significantly higher strength (620 MPa yield vs 550 MPa) while maintaining good -20°C impact toughness (47J vs 34J), allowing for lighter tower sections or higher load capacity in the same thickness.
Is Q620FTD suitable for offshore wind?
Yes, its high strength and -20°C impact toughness meet requirements for many offshore wind projects in temperate and cold seas. For arctic offshore, consider Q620FTE (-40°C).
What is the typical delivery condition for Q620FTD?
It is commonly delivered in Quenched + Tempered (QT) or TMCP to achieve the 620MPa yield strength and 47J impact energy at -20°C.
Third-party inspection available?
SGS, BV, TÜV inspection can be arranged at extra cost; mill certificate EN 10204 3.1 is always included with full test results.