A gamma ray thickness gauge for hot steel strips and tubes

A prototype gamma ray thickness gauge for hot mills rolling steel strip of 0·05 in. to 0·30 in. thickness is described, which uses a scintillation detector and provides distinct readings at short time intervals. Each reading represents the mean thickness of the strips during the preceding interval. The result is displayed on a lamp board and gives a visual picture of the longitudinal profile of each strip. Automatic standardization whilst no strip is passing through the measuring head is incorporated. Results obtained and performance of the instrument are presented and discussed. An adaptation of the above instrument for gauging the wall thickness of hot steel tubes is described.