Effect of mould operation and wear on product quality in a copper casting and rolling line

This study examines the influence of casting speed on solid-phase formation in copper billets during rotary continuous casting through numerical modelling and experimental analysis of an operational mould segment. The simulation identified an optimal casting speed range of 10–11 m min−1, under which billet solidification completes within the lower region of the casting wheel, minimising internal defects and improving billet integrity. To evaluate the effect of mould wear on product quality, a section of the casting wheel removed after operational service was examined. Analysis showed that the primary damage mechanisms are surface wear and longitudinal crack formation. During operation, liquid copper penetrates cracks in the mould to a depth of 3.0 ± 1 mm, forming localised adhesion to its surface. Upon detachment of the billet from the mould, copper particles that had penetrated the cracks are torn off, typically weighing 0.5 ± 0.25 g, and in some cases, larger conglomerates up to 3.0 ± 2.0 g generating surface defects and affecting wire rod quality. The novelty of this study lies in the proposed mechanism connecting mould surface degradation with the initiation and evolution of surface defects from billets to wire rod.