SEVERAL PROBLEMS ON OXYGEN PRACTICE IN IRON AND STEEL MAKING

Abstract

Application of oxygen to iron and steel making is discussed on the basis of its, general trends in Europe and America as well as experiments carried out in Yawata Iron & Steel Works, concerning a low shaft experimental furnace, open hearth furnaces and an experimental converter.
In the low shaft furnace were examined effects of raw material size, oxygen percentage in the blast, etc. on the furnace conditions. It was found possible, as one of the results, that under an adequate condition pig iron for steel, that for foundry, ferro-manganese, etc. could be produced even with a weak coke.
As is universally known, in the open hearth furnace, application of oxygen resulted in cutting melting hour and fuel rate.
A 5-ton top-blown converter was operated, for production of various sorts of steel. Among its fruitful results it was found that by blowing-in highly pure oxygen the nitrogen in steel was dimished to as low as 0.003 per cent, and this stoods comparison with that of open hearth steel.
The property examination conducted in various aspects of the steel thus produced showed that it cauld compete with the open hearth steel satisfactorily and that P as well as N content had a remarkable effect on the properties of the converter steel.
The further improvement of quality of the converter steel should be expected through the betterment of practice.