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Hot rolled straight round steel bars for reinforced concrete in GB 13013-1991 has been the most commonly used non-alloy and low alloy steel bars in China, used for the construction and reinforcement of concrete structures.
The steel bars used in GB 13013-1991 have good plasticity and toughness, excellent weldability and brazeability, good corrosion resistance and great uniformity and reliability when used in concrete. The steel bars are also characterized by their long service life and good environmental performance, as they are produced with 100% recycled materials and contain no inorganic pollutants.
By adhering to strict steel bar production standards and processes, steel bar mills can ensure a high level of quality and safety in their products. After the primary cold-rolling process, the surface of the steel bars is finished mill processed to reduce the dimensional width and thickness deviations, remove the rust and dirt from the surface, and increase the surface finish. All the surface defects, such as crevices, notches, unglued, layers and cracks, shall also be removed during this process. In order to ensure the quality of the steel bars, all measurements, including lengths and diameters, shall match the given requirements for the specific product. The final objective is to obtain a uniform diameter without remarkable differences in the surface appearance.
Once the steel bars are ready for delivery, they shall be properly packed in marked bundles and protected by a wrapping material to prevent damage and painting during transport. The product and bundle marking process must be strictly controlled to minimize the possibility of inaccurate bundle markings that could impact the identification of the mill, grade of the steel and other details.
Adhering to the GB 13013-1991 standard can provide engineering personnel and product users with confidence that the hot rolled straight round steel bars for reinforced concrete will be produced to agreed specifications and at the quality level expected. Meanwhile, the quality control processes enforced by the technical normative document should ensure that the delivered steel bars are fit for their intended use, within the agreed tolerance limits.
