As Asano Zosen has blown down his unique blast furnace about 3 months for the timely repair last year, his steel work has been compelled to adopt, during this interval, the cold metal process instead of the conventional hot metal one.
The experiences with cold metal have proved, contrary to our expectations, so favorable, for cold one, that the preoccupation, which prevailed there up to that time, the hot metal process should surpass the cold one exceedingly, has faded.
Why not the hot metal process so superior to cold one, as considered generally, or as calculated. only thermally? The author found, after his several experiments, the answers.
Primary the hot metal process is less of cold materials than the cold metal process just by the amount of its molten pig. The decrease of cold materials charged in the furnace means directly the drop of the thermal efficiency of the furnace. (second experiment)
Secondary the cold materials below the surface of molten pig form one pasty huge block together with molten pig, which sticks all over the hearth bottom of the furnace, and this sticky block becomes thermally inactive zone (first experiment)
Therefore the thermal superiority of the hot metal process to that of cold metal ought to be the surplus of the advantage of heat amount brought from the outside of furnace by molten pig over the disadvantage caused by the forgoing two reasons. This is why not the hot metal process so advantageous as considered or calculated on desk.
Further the author assumed that the thermal efficiency should be proportional to the surface area of the heap which form the cold materials in the furnace, and found that the inductions derived from this assumption go well with practice.

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Die Bandeisenindustrie begann mit der Beendigung des grossen Weltkrieges in dem Wirtschaftsleben der Voelker eine von Jahr Zu Jahr an Bedeutung immer mehr zunehmende Rolle zu spielen, die Bedarfszunahme in Bandeisen steigerte sich mit einer ungeheueren Geschwin-digkeit. Ursache hierzu war die gewaltige Entwicklung der Blech-Metallwaren-Stanz-Fahrrad-Automobil-und Flugzeugindustrien, die in ihrem Bestreben die Herstellungskosten zu senken von der Verwendung von Blechtafeln, wo es nur moeglich war, abgingen, um an deren Stelle Bandeisen treten zu lassen. Diese Entwicklung zeigte sich auch in der japanischen Industrie und kommt in der sehr schnell steigenden Einfuhr zum Ausdruck (Abb, 1.) Ausgesprochene Bandeisenwalzwerke bestanden bisher in Japan noch nicht. Sofassten die Kawasaki Dockyard Co. den Entschluss ein Bandeisenwalzwerk zur Herstellung von Bandeisen von 70 bis 250mm Breite zu errichten. Um dieses Walzwerk stets wirtschaftlich betreiben zu koennen, wurde es so bestellt, dass auch Roehrenstreifen von 70 bis 250mm Breite und ausserdem Platinen bis 250mm Breite derauf hergestellt werden koennen.
Ausser diesem Bandeisenwalzwerk wurde auch noch gleichzeitig ein 750er Trioblockwalzwerk aufgestellt, um auch die verschiedenen Knueppel bezw. Platinen, die fuer das Bandeisenwalzwerk als Ausgangsmaterial erforderlich sind, im eigenen Werke herstellen zu koennen. Auf diesem Blockwalzwerk werden auch erstmalig fuer Japan quadratische Rohrknueppel von 90-190mm wie sie fuer die Herstellung nahtloser Rohre nach dem Ehrhardt Verfahren notwendig sind, gewalzt.
Beide Walzwerke wurden im August und, September vorigen Jahres in Betrieb genommen

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The author has measured the thermal Conductivity, specific gravity, mechanical, corrosive and erosive properties, and practical value on the small condenser during 4 years, about 9 kinds of the material for condenser tube.
From the result of the above test, he can find a very good material for this purpose.

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The mechanical properties of wrought "Silzin-Bronze" which was invented by Dr. T. Ishikawa early in 1928, -a few years later, the similar alloy "Tombasil" Came out in germanyare fully shown. The effects of aluminium on the mechanical and chemical properties of wrought Silzin-Bronze have been investigated, and a new alloy series "SSZ" discovered. The alloys "SSZ" are strong & ductile and far better corrosion-resisting to sea water than Silzin-Bronze. Some brittleness of wrought Silzin-Bronze, caused by annealing, is shown to vanish nearly by adding aluminium.
The mechanical and corrosion-resisting properties of "SSZ" & "Silzin-Brimze" are far superior to those of P.M.G. Metal.
The authors also have studied the mechanical & chemical behaviour of some industrial copper alloys containing silicon, v.z, P.M.G. Metal, Tungum Alloy, A.R (the authors' invention), Everdur, and Herculoy. The comparison of these alloys is shown in the accompanying table.

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