Where is S690Q steel used?
S690Q steel is a high-strength, fine-grain structural steel (HSLA) that's quenched and tempered (Q) for exceptional strength (minimum 690 MPa yield) and toughness, used in heavy-duty applications like bridges, cranes, and machinery where weight savings and high load capacity are critical, conforming to EN 10025-6 standards. Its designation breaks down as 'S' (Structural), '690' (min yield strength in MPa), and 'Q' (Quenched & Tempered).
Key Characteristics
High Strength: Minimum yield strength of 690 MPa, with typical tensile strength between 770-940 MPa, providing excellent load-bearing capacity.
Toughness: Good impact toughness, often guaranteed at temperatures down to -20°C.
Fine Grain: Achieved through heat treatment, contributing to its strength and toughness.
Weldability: Considered to have good weldability for its strength class, though proper procedures like preheating are usually needed, especially for thicker plates.
Low Alloy: A controlled chemical composition that supports its high performance.
Applications
Heavy construction equipment (excavators, loaders)
Bridges and offshore structures (drilling rigs, windmill supports)
Cranes and lifting equipment
Pressure vessels
High-load structural elements in various machinery
Designation Breakdown
S: Structural Steel
690: Minimum Yield Strength (690 MPa)
Q: Quenched and Tempered (heat treatment condition)
Where is S690Q steel used?
S690Q steel, due to its exceptional strength-to-weight ratio, is primarily used in advanced engineering applications where reducing weight and structural mass is critical without sacrificing safety or performance.
Heavy Mobile Cranes & Lifting Equipment: For booms, telescopic arms, and chassis, where high strength minimizes weight and maximizes lifting capacity and reach.
Mining, Quarrying, and Earth-Moving Machinery: In excavator arms, dumper truck frames, and drilling equipment to handle extreme dynamic loads and abrasive environments.
Advanced Construction and Structural Engineering: For key components in bridges (especially movable parts), high-rise buildings, and special structures where reducing dead load is a major design goal.
Transport and Commercial Vehicle Superstructures: In chassis for special vehicles like fire trucks, airport crash tenders, and advanced trailers that require a robust yet lightweight frame.
Material Handling and Logistics: For heavy-duty forklift masts, port container handling equipment, and automated storage systems.
Renewable Energy Infrastructure: In critical components for wind turbine towers (particularly for higher hub heights) and hydropower systems to withstand immense structural stresses.
In summary, S690Q is the material of choice for the most demanding parts of machines and structures where saving weight directly translates to increased efficiency, higher payloads, greater reach, or improved energy performance.
What is S690Q steel?
S690Q is a high-strength quenched and tempered structural steel grade with a minimum yield strength of 690 MPa, often used in demanding construction and lifting applications.
What are the properties of S690Q steel?
S690Q offers high strength, good toughness at low temperatures, and excellent weldability due to its quenched and tempered microstructure.
What is the difference between S690QL and S690Q?
S690QL is a sub-grade with specified low-temperature impact toughness, while S690Q is the base grade; both share the same minimum yield strength.
Where is S690Q steel used?
It is commonly used in heavy machinery, mobile cranes, mining equipment, and advanced structural components where high strength-to-weight ratio is critical.
How to weld S690Q steel?
Welding S690Q typically requires low-hydrogen electrodes, preheating, and controlled heat input to maintain its mechanical properties and prevent cracking.
What is the chemical composition of S690Q?
S690Q contains elements like carbon, manganese, silicon, and micro-alloys such as niobium, vanadium, and titanium, with precise limits to ensure its properties.
Is S690Q steel corrosion resistant?
No, S690Q is not inherently corrosion-resistant; it requires protective coatings or paints for use in corrosive environments.
What are the machining guidelines for S690Q?
Machining S690Q requires robust tools, adequate cooling, and slower speeds due to its high strength and hardness.
What is the price of S690Q steel plate?
The price of S690Q varies based on thickness, quantity, and market factors, but it is generally more expensive than standard structural steels due to its advanced processing.
Full specification and details are available on request. The above information is provided for guidance purposes only. For specific design requirements please contact our technical sales staff.
