S690QL is a high-strength, low-alloy structural steel grade specified by the EN 10025-6 standard, known for its excellent strength, toughness, and weldability. It is heat-treated using the quench and temper process.
S690QL steel plates are high-strength, quench-and-tempered structural steels for applications requiring superior mechanical properties. They have a minimum yield strength of 690MPa and exhibit good weldability and formability compared to conventional mild steel grades. The higher yield strength and excellent toughness make them well-suited for general fabrication and load-bearing components in construction sites where they can be subjected to considerable stresses. Additionally, these plates exhibit excellent corrosion resistance due to what is known as their 'weathering' grade characteristics, which allow them to withstand exposure to harsh weather conditions such as rain, snow and fog without losing their integrity or showing signs of degradation. Overall, they provide great value for money by simultaneously being incredibly strong yet cost-effective!
| Typical chemical composition of S690QL % Max | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
C |
SI |
Mn |
P |
S |
N |
B | Cr | Cu | Mo | Nb | Ni | Ti | V | Zr |
| 0.2 | 0.80 | 1.70 | 0.025 | 0.015 | 0.015 | 0.005 | 1.50 | 0.50 | 0.70 | 0.06 | 2.0 | 0.05 | 0.12 | 0.15 |
| Mechanical Properties of S690QL | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Designation | Mechanical Properties (ambient temperature) | ||||||||||
| Steel Name | Steel Number | Min. Yield Strength ReH MPa | Tensile Strength Rm MPa | Min. & elongation after fracture | |||||||
| Nominal thickness (mm) | Nominal thickness (mm) | ||||||||||
| >3 <50 | >50 <100 | >100 <150 | >3 <50 | >50 <100 | >100 <150 | ||||||
| S690QL | 1.8931 | 690 | 650 | 630 | 770/940 | 760/930 | 710/900 | 14 | |||
applications
1. Cranes and Lifting Equipment
In the crane industry, the strength-to-weight ratio is a critical performance metric. Utilizing S690QL allows manufacturers to produce thinner yet stronger telescopic booms, jibs, and chassis. This structural weight reduction directly translates to increased maximum lifting heights and extended working radii. Whether for all-terrain cranes, crawler cranes, or port handling equipment, this steel provides the necessary resistance to bending and fatigue while maintaining safety under immense loads.
2. Heavy Transport and Mining Equipment
For heavy-duty vehicles such as dump trucks, excavators, and bulldozers, S690QL offers superior load-bearing capacity and impact resistance. In harsh mining environments, equipment must withstand constant stress from hauling massive rock volumes. Using S690QL minimizes vehicle deadweight, which significantly improves fuel efficiency and increases the effective payload per trip. This optimization drives higher productivity and lower operational costs for mining and logistics companies.
3. Steel Structures: Bridges, Offshore, and Wind Power
In large-scale infrastructure, S690QL is the preferred choice for achieving long-span designs. For bridge construction, it reduces the required section size of steel girders, lowering both self-weight and foundation costs. In the offshore sector-including drilling platforms and wind turbine towers-its excellent Charpy V-notch impact energy at -40°C ensures structural integrity against freezing temperatures and violent wave impacts, guaranteeing long-term reliability in extreme marine environments.
4. Machine Building and General Construction
In general industrial applications, S690QL is used for high-pressure vessel supports, hydraulic roof supports, and heavy-duty frames for skyscrapers. Its excellent weldability and cold-forming properties allow engineers to design complex components that can handle high stress. By replacing conventional carbon steels with S690QL, companies can reduce total material usage, leading to lower welding costs, reduced transport emissions, and a more sustainable approach to high-end manufacturing and green construction.
For more details about GNEE's steel products, contact us at beam@gneesteelgroup.com. We look forward to working with you.
What is the price of S690ql?
₹ 130/KgS690 QL plate is a high-strength, quenched, and tempered steel plate designed for use in structural applications that require high strength and excellent toughness.
What are the key mechanical properties of S690QL?
S690QL is a quenched and tempered high-strength structural steel with a minimum yield strength of 690 MPa and good toughness, typically achieved through controlled rolling and heat treatment.
What grade is S690QL material?
S690QL is a high strength quenched and tempered steel grade that complies to steel specification EN 10025. The designation S690QL refers to a minimum yield strength of 690 MPa.
How does S690QL compare to S355JR in terms of strength and application scope?
S690QL has significantly higher yield and tensile strength than S355JR, making it suitable for weight‑saving structures such as crane booms and offshore platforms, whereas S355JR is used in general construction.
What is the typical heat treatment process for S690QL?
S690QL is usually produced by quenching followed by tempering, which refines the microstructure and balances high strength with adequate toughness.
How does the weldability of S690QL compare to S460NL?
S690QL has higher hardenability and requires more stringent preheating and interpass temperature control than S460NL to avoid cold cracking, especially in thick sections.
What are the common applications of S690QL?
S690QL is widely used in heavy‑duty applications such as mobile cranes, hydraulic supports, mining equipment, and large‑span steel structures where high strength and reduced weight are critical.
What does the "QL" in S690QL stand for?
The "Q" indicates quenched and tempered (quenched), and the "L" indicates improved low-temperature toughness compared to the non-L version (S690Q).