A METHOD FOR CLASSIFICATION OF CONTINUOUSLY CAST STEEL SLAB WITH RESPECT TO QUALITY USING ULTRASONIC TECHNIQUE

摘要

The invention relates to a method for assessing the quality of steel slab, the method comprising steps of: determining various no. of defect size in terms of ultrasonic echo amplitude present in various slab samples along with their corresponding depth from the scanning surface, the slab being made of a process; calculating the normalization factor for eliminating depth effect on amplitude of the N x = A FBH x A f ultrasonic echo, the normalization factor (N x ) where A FBH X is the depth and A f is the ultrasonic echo amplitude; multiplying each amplitude with the normalization factor, to generate normalized amplitude, the normalized amplitude represents the defect severity irrespective of its location (depth); distributing the normalized amplitude for the various slabs, thereby generating a master graph; and determining defect size and multiplying with normalization factor of a fresh steel made by the said process and further distributing over the master graph and to assess the quality.