Apparatus for descaling metal strips

Abstract

An apparatus is provided for descaling hot rolled steel strips or sheets by abrasion. This is preferably accomplished with an abrasive roll, which comprises a hub having a multiplicity of abrasive sheets extending generally radially therefrom and rotated at high speed with outer edges in contact with the metal strip moving thereby. The abrasive roll can have a length less than the width of the strip with means provided for maintaining one end of the abrasive roll in alignment with one longitudinal edge of the strip. This improves the life of the abrasive sheets since they do not move transversely over the longitudinal edge of the strip. The steel strip also can be supported in a curved manner to present a convex surface toward the abrasive roll when in contact therewith. The bent configuration of the strip helps to loosen the scale and hastens the descaling operation. For a lower production and lower cost descaling operation, one abrasive roll can be used with the steel strip coiled and uncoiled in a manner to present opposite surfaces toward the abrasive roll when it is moved thereby in two passes. To further improve the life of the abrasive roll, it is periodically checked to determine its condition of balance. Weights can then be added to the hub to restore the balanced condition, as necessary. A back-up roll for supporting a steel strip in contact with the abrasive roll can have metal collars supporting edge portions of the strip to prevent undue wear of the back-up roll.