Patent ID: 8960264
Filing Date: 2015-02-24
Classification: B22C,B22D

Abstract:
1. An apparatus for continuously casting metal strip comprising: a pair of counter-rotatable casting rolls each having casting surfaces with a center portion of at least 60% of the width of the casting rolls, two edge portions each of up to 7% of the width of the casting rolls, and at least one intermediate portion between each edge portion of the casting rolls and the center portion of the casting rolls, each edge portion having an average surface roughness between 3 and 7 micrometers Ra, the center portion of the casting rolls having an average surface roughness tapered across the width and between 1.2 and 4.0 times the surface roughness of the edge portions of the casting rolls, and the intermediate portions of the casting rolls having an average surface roughness between the average surface roughness of the edge portions of the casting rolls and the center portion of the casting rolls, and laterally positioned to form a gap at a nip between the casting surfaces of the casting rolls through which thin cast strip can be cast, a metal delivery system adapted to deliver molten metal above the nip to form a casting pool supported on the casting surfaces of the casting rolls and confined at the edges of the casting rolls, and a drive system adapted to counter-rotate the casting rolls forming metal shells on the casting surfaces of the casting rolls that are brought together at the nip to deliver cast strip downwardly with varied thicknesses of the metal shells across the strip width.