The S235JR (E235B) square steel pipe is a widely used low-carbon structural steel tube designed for general engineering, construction, and mechanical applications. Belonging to the EN 10025 and EN 10210 standards, this material is known for its excellent weldability, high plasticity, and good impact toughness. Its balance of strength, ductility, and cost-effectiveness makes it one of the most common structural steel grades in Europe and globally.