PROGRESS OF MEASUREMENT TECHNIQUES IN IRON AND STEEL INDUSTRY

Abstract

Therea re two main fields of the measuring techniques developed and applied to the iron and steel industry in Japan during these ten years since the War end. The one is that for the heat economical request which has arisen from the insufficiency of fuel and the other is - that for the improvement of quality and yield of products, which has been studied at the 19th and the 54th Research Committes of the Japan Society for Promotion of Science long before the War.
1. Progress of the Instrumentation for the Heat Econony.
In order to overcome the worst condition of fuel at the time of the after-war, the movement of heat control was vividly started in iron and steel industry and the instrumentation was taken to be important to be applied. In December, a Committee of Instrumentation was organized to study various problems to be solved to realize the instrumentation in iron and steel industry.
In June,1949, the Technical Organiration of Heat Economy was started, under which a Special Committee of Instruments was organised to study the instrumentation techniques. This Committee worked to elevate the interest to instrumentation among the steel works in Japan, and the instrumentation of open hearth furnaces and heating furnaces advanced to be adopted very rapidly in the great many works.
The Committee decided to adopt the standard instruments to be installed for the furnace operation. The instrument makers developed various instruments of new idea to meet the special requirements, which were proposed by the Committee. After some time of researches and studies proceeded with the instrumentation, the Commitee found many problems to be solved and made success in determining the normal conditions of operation.
In November,1953, the Committee published a manual of the instrumentation which covered the administration, the kind of instruments, the methods of installation, maintainance, repair, calibration, instrumentation, and so forth.
2. Progress of the Measuring Techniques for the Improvement of Quality of Products.
Among various measuring techniques to improve the quality of products, the high temprature measuremnt for steel making have been studied since 1935 by the Second Sub-Committee of the 19th Research Committee. In the pre-war period, many fruitful results were obtained in contributing to improve steel making. After the war-end, some of the items to be studied by the Subcommittee were changed to meet the urgent need, while some others were continued to match the conditions at that time.
Among the latter items, there was the development of photoelectric pyrometer, which was effectively used to measure continuously and to control the temperature of the ceiling of open hearth furnaces. Another item was the cobalt glass for use before the open hearth furnace. Before the war Sub-committee studied the standardization of the cobalt glass and after the war the sub-commitee studied it from the view point of temperature deterimination which was analysed by colorimety. This new idea of research resulted in the development of a coloritheter without an artificial light source and in the standardization of the cobalt glass of two kinds for forging. In the next step the cobalt. glass was studied from the view point of protection of eyes against non-visible rays, without changing the hue. It was in effect in getting a blue glass which guard the eyes against even infra-red light.
The third item which is very important is the temperature measurement of molten steel in the open hearth furnace. Before the war there were records of temperatue distribution in the furnaces, with specially designed direct immersion thermo-couples. After the war they studied practically the constructions of the thermo-couples which were suited to be used for daily works and made success in using them daily combined with electronic recorders. They were usually calibrated with Pd-wire method.