Patent ID: 6557622
Filing Date: 2003-05-06
Classification: B21B,C21D

Abstract:
A method of quenching a surface of an as-cast steel product conveyed along a casting line of a continuous casting steel mill, the casting line including at fixed positions,a caster assembly, and a reheat furnace, the method comprising for given input parameters including casting line speed and selected steel product dimensions,(a) applying a differentiated spray of cooling fluid to the as-cast steel product, the spray characteristics of the spray being selected to be sufficient to quench the product such that a surface layer of the product is transformed from an austenitic to a non-austenitic microstructure, and the differentiation of the spray being selected to respond to the pre-quench surface temperature profile of the product such that the uniformity of the post-quench surface temperature profile of the product is enhanced; and (b) heating the product to a suitable temperature to re-transform the transformed surface layer into fine-grained austenite thereby inhibiting formation of surface defects in the product.