High Quality Carbon Structural Steel Cold Rolled Steel Sheet and Steel Strip GB/T13237 -- 1991
High quality carbon structural steel cold rolled steel sheet and steel strip referred to in this standard are commonly named as 08F, 10F, 15F, 20F, 25F, 30F, 35F, 40F, 45F and 50F steel.
08F, 10F, 15F, 20F, 25F and 30F steel are plain carbon steel used to produce cold rolled steel sheet and steel strip. In order to ensure their uniformity, the chemical composition of steel in each grade should meet the requirements of the present standard.
The cold-forming properties of steel are commonly evaluated by the forming ratio. In the present standard, the forming ratio of 08F, 10F, 15F, 20F, 25F and 30F steel shall meet the requirements of the present specification.
The weldability and post-weld hardening behavior of steel are both important technical performance parameters. The present standard has established minimum strengthen weldability requirements for 08F, 10F, 15F, 20F, 25F and 30F steel, which means that their hardenability shall not deteriorate after welding.
The mechanical properties of steel are important indicators to evaluate the strength of steel and plasticity of steel. In the present standard, 08F, 10F, 15F, 20F, 25F and 30F steel shall meet the requirements of mechanical properties prescribed in the present standard.
The surface quality and dimensional tolerance control of cold rolled steel sheet and steel strip are also important technical indications, which must be strictly controlled in order to ensure the final product performance. The present standard also specifies requirements for surface quality, flatness and dimensional tolerance for cold rolled sheets and strips.
35F, 40F, 45F and 50F steel are micro-alloyed by a small amount of elements such as Ti and Nb, which are not present in plain carbon steel, and the strength and ductility of these structural steel can be further improved.
The chemical composition of 35F, 40F, 45F and 50F steel shall meet the requirements of the present standard. The present standard also stipulates the requirements for cold-forming of these structural steel, as well as their mechanical properties, surface quality, flatness, and dimensional tolerances.
In summary, the present standard High Quality Carbon Structural Steel Cold Rolled Steel Sheet and Steel Strip GB/T13237 -- 1991 mainly specifies the chemical composition requirements, cold-forming characteristics, weldability performance requirements, mechanical properties, surface quality requirements and dimensional tolerance requirements of 08F, 10F, 15F, 20F, 25F, 30F, 38F, 40F, 45F, and 50F steel. This standard provides strong technical guarantees for the production of steel sheet and steel strip products meeting the specified requirements.
