It was not solved technically to use titanium containing iron ore in the blast furnace, because its operation becomes gradually difficult by the formation of solid matter at the furnace botton in proportion to the titanium quantities charged. From the previous studies made in our and foreign countries, it is assumed that the formation of this solid matter is due to poor fluidity of pig iron and slag, which seems to be caused by ferrotitanium, lower oxides, nitrogen and cyanogen compounds of titanium formed during the reduction of TiO₂ at the blast furnace high temperature part. It is also well known that TiO₂ itself gives the good influence to the fluidity of slag.
Hence, to solve this problem the authors performed the smelting test on March 1937 with the experimental 1 ton Blast Furnace, so that during the smelting process, the TiO₂ charged would go to the slag as much as possible and the inner temperature of the furnace be kept as low as possible by the formation of highly acid and easy melting slag. The result of this test was so successful, that we found no trouble at the furnace bottom even by charging 100% of the sintered iron sand which had 5.5% of TiO₂. So, to confirm this result more, we made the industrial tests of using titanium containing sintered iron under the above mentioned method on Dec. 1937 with the 220 ton Blast Furnace of Wanishi works, Japan Iron & Steel Co., and on May 1940 with the 10 ton Charcoal Blast Fur nace of Minari Plant, Teikoku Seitetsu Co., Although the TiO₂ in the slag were 5.8% and 18.7% respectively, the results were also very successful.
The practical smelting methods obtained from the above tests are as follows:
1. Keep the CaO/SiO₂ of slag to 0.8-0.9 against the ordinary ratio of 1.1-1.4.
2. Prevent the reduction of TiO₂ as small as possible by keeping the furnace temperature at its lowest within the possible operating condition. In our test this temperature was 50-100°C lower than the ordinary condition.
3. Use a suitably larger quantities of Mn than the ordinary operation, so the fluidity of slag becomes better and make it possible for low temperature operation Also, this acid and low temperature operation compensates the degradation of desulphurization.

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A research committee was formed im March 1947, with the object studying the basic open hearth steelmaking practice to seive the after-war conditions Four subjects have been discussed, which so far arrived at the following conclusions- (1) Low charge proportion of pig non- By the use or carburising materials the proportion may be lowered to approximately 25%, (2) Oil burners- Various designs of fuel oil burners are in use, whose advantages and disadvantages are not yet decisive. (3) Dolomite bed- Raw dolomite bed gave quite satisfactory results at one works. (4) Use of oxygn in open hearths-Literatures were mvestigated and discussed

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Synopsis: -Following the first report (Tetu to Hagane, Vol. 33 (1947) July- September P. 17-18), the present paper dealt mainly with the measurement of high temperature, by using the Fe-Mo thermo-couple as the substitute material of the Pt-Pt·Rh thermo-couple. From the experimental results, We came to the conclusion that the Fe-Mo thermo-couple which was protected by the specially deviced apparatus showed the results nearly equal to the Pt-Pt·Rh thermo- couple for the measurement of the high temperature up to 1400°C, such as the heating temperature of forged steels and tapping temperature of molten cast irons and non-ferrous alloys.

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