Q390NB is a normalized high-strength structural steel plate manufactured according to GB/T 1591. With a minimum yield strength of 390 MPa, Q390NB provides higher strength than conventional structural steel grades while maintaining good weldability and stable mechanical properties.

The normalized delivery condition improves the internal structure of the steel, providing reliable performance for welded structures and engineering applications requiring consistent quality.

Q390NB is commonly used in industrial structures, machinery manufacturing, and general heavy fabrication projects.