The paper deal with experience with the introduction of production of ribbed wire from B500B steel on the cold stretching line KOCH in ArcelorMittal Ostrava. The basic principle of work hardening during cold stretching is introduced. Distribution of mechanical properties along the wire length of both hot rolled and cold stretched wire were performed. Statistical analysis has shown that there is a definable cause affecting the manufacturing process. Because of this, the yield strength, tensile stress and elongation to fracture values showing a trend along the wire length. It has been proven by measuring of the temperature of the wire at the conveyor by thermovision, that cooling of the wire rod on the chain conveyor is this definable cause. Different parts of the wire are cooled with varying intensity due to different densities of wire loops stacking on the conveyor. This fact directly affects the mechanical properties of the wire. Higher cooling rates result in higher yield strength and tensile stress values and lower elongation to fracture values. The effect of cold stretching on the change in the trend of mechanical properties over the length of the wire was also investigated. Interestingly, the variability of mechanical properties after cold stretching has increased.
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