Influence of the hydraulic pump unit on the quality of the rolled surface

To ensure the competitiveness of rolled metal in the modern market, the decisive factor is the quality of the rolled surface (defects with a depth of no more than 0.2 mm are allowed without stripping). Rolling processing is a source of formation of small surface defects, most of which are obtained in the process of deformation of a continuously cast billet (hereinafter referred to as CCB, billet) at hot rolling mills in the presence of areas with non-removed furnace scale. This is the main reason for the formation of such types of surface defects as rolled scale, ripple, scale shells, which reduces the quality of the rolled surface and increases the sorting of metal with surface defects. In addition, the scale not removed from the surface of the CCB has a negative impact not only on the quality of metal products, but also on the operation of rolling equipment.

One of the directions that allows to achieve high quality of the surface of long products in production conditions is the effective removal of scale from the surface of the initial billet before hot deformation. Scale removal from the surface of the workpiece is carried out on the installation of a hydraulic descaling unit, but not always a satisfactory (complete) scale removal occurs.

To determine the cause of poor – quality scale removal before hot deformation, the efficiency of the hydraulic descaling unit and the state of the metal – scale interface surface were investigated.

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