Detecting faults in rolled metal products - using surface radiation to infer the presence or absence of faults

摘要

Method of detecting faults in rolled metallic products (I) comprises the detection of electromagnetic radiation emitted by =1 surface of (I) during h ot rolling, and from this detected intensity the surface temp. of (I) at the detection point (II) is deduced. From this a graph is drawn showing the surface temp. of (I) at (II) and the graph is used to obtain information relating to the presence or absence of internal anomalies at (II).