Abstract: According to a method of operating a blast furnace, pure oxygen, pulverized coal, and a temperature control gas which substantially does not contain nitrogen are blown from tuyeres. A preheating gas which substantially does not contain nitrogen is blown from an intermediate shaft level. A blast furnace gas which substantially does not contain nitrogen can be produced from a furnace top.

Abstract: A side dam block disposed along the widthwise end portion of a block mold is supported by springs such that the side dam block is pressed against the casting flat surface of the opposing block mold so that gap between the opposing block molds can be suitably adjusted.

Abstract: A method for refining powders comprising the steps of: (a) adding polytetrafluoroethylene powders to non-oxide ceramic powders to form a mixture by mixing; and (b) heating the mixture in non-oxidizing atmosphere to convert oxides existing on the surface of the non-oxide ceramic powders into gaseous fluorides, and removing gaseous fluorides. The fluororesin is a polytetrafluoroethylene resin. The heating temperature in the non-oxidizing atmosphere is 500.degree. C. to 1300.degree. C.

Abstract: Downward force resulting from the block mold and its carrier of the upper mold assembly which move downwardly toward the upstream end of the mold cavity defined by the vertically spaced-apart upper and lower mold assemblies is transmitted to the block mold and its carrier of the upper mold assembly passing the upward path extending upwardly from the downstream end of the mold cavity so that the distortions of the cross-sectional configuration and size of the mold cavity due to the weight of the block molds and their carriers are prevented.

Abstract: A fish cage for cultivating fish comprises a hull shaped vessel composed of outer side platings, inner bottom platings, screen bulkheads and a deck. A device for floating a hull shaped vessel on the water is provided, and openings are formed in the outer side platings and inner bottom platings and covered with nets so as to let sea water flow in and out of the hull shaped vessel. The device for floating the vessel on the water is formed by tanks arranged on the upper side of the outer side platings to hold air. Openings are provided in the bulkheads and covered with nets affixed to the screen bulkheads for letting sea water flow in and out. Openings are also provided in the outer side platings on the bow and on the stern of the vessel for letting sea water flow in and out.

Abstract: The invention provides an apparatus for conveying steel bar materials sent from the exit of a stand of 2 strand rolling line to a cooling hearth, in which improved conveying and dropping of the bar materials is accomplished. Four conveying/dropping components are arranged in two pairs, which are disposed at determined positions, so that the bar materials may avoid being bent or twisted during conveying and dropping, and the treating speed of the rolling line is accelerated.

Abstract: A high strength and corrosion resistant titanium alloy having excellent corrosion-wear properties may be prepared in that Al and Mo are added as alloying elements in specific amounts, and if Zr in a specific amount is further added, the strength and the corrosion-wear properties would be more improved.

Abstract: A method for operating a blast furnace by inferring the operating conditions in the blast furnace, on the basis of data supplied from sensors set in the blast furnace and also on the basis of the knowledge base formed by experience on the operation of the furnace by a small-scale computer and various processing units provided within the computer. Prior to the inference, the data from the sensors are processed by a large-scale computer and various processing units provided within the large-scale computer. The inference is performed by using certainty factor values, thereby making diagnosis of slip, hanging and channeling.

Abstract: In a mold cavity and/or in horizontal cooling zones, upstream- and downstream-side gears are drivingly coupled to each other through an endless-track-like member to which the tensile force is exerted by a tensioner, so that gaps between the adjacent block molds can be eliminated and therefore intrusion and leakage of a cooling liquid and melt are prevented.

Abstract: A fish breeding apparatus with an exchangeable net comprises a hull shaped fish cage with side platings, a bottom plating, screen bulkheads and a deck. A pay out roller for paying out a net into the cage is provided, along with a device guiding the net so that an end of the net passes through a predetermined course. A coil-up roller is provided for coiling up the net. Edges of the net each are connected to a guide rope and guide floats, the guide rope is turn being connected, through joint wires, to a side edge portion of the net. The guide floats are fixed to the guide rope and hold the guide rope in the guide rail.

Abstract: The present invention relates to a highly corrosion resistant surface-treated steel plate. The steel plate of the invention comprises a zinc deposition or zinc alloy deposition film as the undercoat deposition layer, a chromate film formed on the undercoat deposition layer and a film of a resin composition formed on the chromate film. This resin composition comprises a substrate resin formed by adding at least one basic nitogen atom and at least two primary hydrogen groups to terminal of an epoxy resin, silica and sparingly water soluble Cr compound. The resin composition may comprise a polyisocyanate compound as the curing agent. Moreover, the resin composition may comprise a silane compound as the crosslinking agent for the substrate resin and silica.

Abstract: A tuyere for a blast furnace comprises water-cooled tuyere; and a burner removably mounted inside the water-cooled tuyere to burning pulverize coal. The burner comprises an inner pipe, an intermediate pipe and an outer pipe which are concentrically arranged. The inside of the inner pipe is used for a pulverized coal path, an oxygen feed path being in between the inner pipe and the intermediate pipe and a flame temperature control gas feed path in between the intermediate pipe and the outer pipe. The burner is equipped with a water-cooled jacket outside of the top end of the burner.

Abstract: The present invention provides a method of efficiently and stably manufacturing a high-purity metal powder of a desired particle size, which is used for powder metallurgy or the like, by generating arc 18 between electrodes 12 and 13 to melt the distal end portions of the electrodes, causing droplets 19 of the molten metal to drop onto rotating disk 14, scattering the dropped droplets by a centrifugal force, thereby cooling the droplets, and an apparatus for the same.

Abstract: The present invention relates to a temper rolling oil which comprises:(A) a water-soluble cationic compound prepared by neutralizing a condensation product obtained by reacting the following compounds 1 to 3 with each other by heating:1. an aliphatic dicarboxylic acid,2. at least one amino compound represented by the following formulae (a) to (c): ##STR1## 3. a particular polyethyleneimine, with an oxoacid of phosphorus, (B) an aqueous rust preventive, and(C) water.The present invention is also concerned with a method of temper rolling which, comprises of conducting temper rolling at a reduction ranging from 0.5 to 30% using a dilute solution prepared by diluting a temper rolling oil of the kind as described above, so that the concentration of a water-soluble cation compound contained therein is 300 to 5,000 ppm.

Abstract: A precoating for a two-piece can, comprising a thermosetting coating and an internal lubricant. The internal lubricant comprises a modified hydrocarbon wax having a structure in which a plurality of repeated units of a fluorine atoms substituted olefin are combined with a hydrocarbon wax.

Abstract: A film forming apparatus comprises a reaction furnace having a reaction chamber therein, injection nozzles for introducing a reactive fluid, provided on the reaction furnace, a discharge nozzle for discharging a reactive fluid, provided on the reaction furnace, and a pair of susceptors located in almost vertical position in the reaction chamber and having facing sides separated by a specified distance. The susceptors include a plurality of depressions formed in the respective facing sides thereof for holding a plurality of silicon wafers. The paired susceptors are rotated in mutually opposite directions.

Abstract: A method for controlling heat conditions in a blast furnace wherein the heat conditions are inferred and judged in comparison of data output from sensor means provided for the blast furnace with knowledge base means formed by accumulated experience on the operation of the blast furnace. The heat conditions are inferred and judged from levels of heat conditions and from levels of transition of heat conditions, wherein data regarding molten metal temperature and those regarding sensors are used. The inference and judgement are carried out by inference engine means included in a small-scale computer.

Abstract: Described is a catalyst used for hydrogen treatment of coal tar characterized in that about 10 to 30 weight percent of Mo oxides as first catalyst component and about 1 to 6 weight percent of Ni and/or Co as second catalyst component, both relates to the total catalyst weight, are supported on a porous inorganic substrate consisting essentially of alumina or silica alumina, and in that the mean pore size is about 8 to 18 nm, the pore size distribution is such that______________________________________ pore size nm volume ratio cc/g ______________________________________ 3.5-5 Less than 0.1 5-8 Less than 0.3 8-18 0.2-0.2 18-30 Less than 0.2 over 30 Less than 0.1 ______________________________________and the total pore surface is higher than about 100 m.sup.2 /g.

Abstract: A method and an apparatus for determining a length of a pipe utilizing sound waves, which comprise: transmitting sound waves having a prescribed frequency and a prescribed transmission intensity toward the interior of a pipe at one end thereof by an oscillator; receiving the thus transmitted sound waves at the other end of the pipe by a receiver; measuring a propagation time required for the sound waves to pass through the air in the pipe from the one end to the other end thereof by a clock; and determining a length of the pipe by a length calculator on the basis of a predetermined propagation velocity of the sound waves in the air in the pipe and the thus measured propagation time of the sound waves.

Abstract: There is disclosed a method for arc welding wherein an electrode wire is rotated to produce an arc rotating at an elevated speed and wherein the arc produced in this manner is used as an arc sensor for making a bevel profiling. According to the invention, the rotational speed of the arc N is set so as to be larger than a constant speed as determined by the time constant of the change of the wire melting speed so that the difference between the welding current when the electrode wire is at the center of the bevel and that when the electrode wire is at the extreme lateral position is increased to improve the bevel profing performance.