TIN COATING WEIGHT GAGE AT U. S. STEEL'S PITTSBURG WORKS.

PITTSBURG works operates three electrolytic tinning lines, each equipped with an x-ray fluorescent coating weight gage. The first gage was installed on No. 3 line in 1972, the second was placed on No. 2 line in 1974 and the third was installed on No. 1 line also in 1974. The gages have been in operation continuously since installation, amounting to over 26,000 running hr. Nearly 5 million coating weight measurmeents have been made. During the period of use, tin consumption has been reduced by an amount equivalent to 0. 01 lb/base box. The benefits derived from the gage are both direct and indirect. A direct benefit of course is reduced tin consumption. Indirect benefits are: Uniform coating weight distribution, top vs. bottom, is maintained. Essentially 100% coating weight testing is obtained; Indication of gradual coating weight trends become apparent. Ready means to monitor plating current efficiency is provided.