Abstract
In iron and steel industry that produces sheet steel, it is very important to measure the strip tension which affects the thickness, shape and rent in the cold rolling process, the hardness and surface fault (Luder's line) in the skin pass process, and the recoiling force, surface fault, work efficiency, quality and so on in other processes. Two load cells of wire strain gages were installed under the bearings of the measuring roll. From a geometrical relation between this roll and two rolls before and behind it, the total and difference of the tensions of both edges of strip were obtained. The stability of reading was within ±3% of full scale under such conditions as the maximum temperature of roll bearing is 40°C, the variation of power voltage 100V±10V and the variation of air temperature 20°C±10°C for 24 hours. The accuracy in static measurement was less than 2%. There has never been the load cell accident for a long time, because the safety load was designed to be twice as much as an estimated value. The equipments of this kind have been installed in many lines with good results. Some of them, for example, have been satisfactorily working for more than three years.
