S690 Steel is a high-strength structural steel known for its excellent mechanical properties and weldability. It is commonly used in construction and heavy machinery due to its ability to withstand high loads while remaining lightweight. The "S" in S690 indicates that it is a structural steel, and the number 690 refers to its minimum yield strength of 690 megapascals. This steel grade is often utilized in applications such as bridges, cranes, and offshore structures. Its high strength allows for thinner sections, which can lead to material savings and reduced weight in engineering designs. Overall, S690 Steel is a reliable choice for demanding structural applications.