S690Q is a hot-rolled hardened structural steel that has undergone subsequent tempering treatment and conforms to the EN 10025-6 standard.

Standard: Hot-rolled product made from structural steel. EN 10025-6: Technical delivery conditions for high-tensile structural steel post-tempering and quenching.

Classification: High-grade structural steel.

Product:Fine-grain steel post-quenching and tempering.

Chemical composition of S690Q steel, %

Mechanical properties of S690Q steel

Analogues to S690Q steel

Application

S690Q steel is used in structures subject to extreme loads: mining and heavy-construction equipment, crane equipment, offshore drilling platforms, supporting structures for wind turbines, bridges and trestles.

Welding

S690Q steel is suited to welding done without preheating or subsequent heat treatment. It is organically weldable as its behaviour during and after welding depends not only on the material, but also on the sizes and shapes as well as the product operation conditions. The requirements for arc-welding must conform to the EN 1011-2 standard

As the product gauge and strength increase, cold-cracking may occur, caused by the following:

• Large quantities of diffusing hydrogen in the weld-seam metal;
• Significant tension-stress concentrations at the weld seam.
• Fragile structure of the heat-affected zone;