Abstract: In a process for the reduction of fine ore by reducing gas in the fluidized bed method, the following characteristic features are realized in order to achieve a uniform and even degree of metallization at optimum utilization of the reducing gas and while minimizing the amount of reducing gas employed, that the fine ore is fractionated by aid of the reducing gas into at least two fractions having different grain size distributions, that each fraction is reduced by the reducing gas in a separate fluidized bed, wherein the reducing gas maintains a first fluidized bed containing the coarse-grain fraction and separates the fine-grain fraction from the same, is accelerated together with the fine-grain fraction, subsequently under pressure release forms a further fluidized bed, into which it is continuously injected in a radially symmetrical manner and from below, and wherein, furthermore, secondary reducing gas additionally is directly injected into the further fluidized bed in a radially symmetrical manner, and th

Abstract: A method for injecting fine iron ore in a smelting reducing process is disclosed, in which the carrier gas for the iron ore is the discharge gas from a melter gasifier without the need of separate carrier gas. It includes the steps of pre-reducing iron ore in a pre-reduction furnace, melting and reducing it in the melter gasifier, supplying the discharge gas from the melter gasifier through an ascending tube to a cyclone and to said pre-reduction furnace, directing the cooled and cleaned fine iron ore through a recycling system and a melting burner into the melter gasifier. A part of the discharge gas is supplied through a venturi scrubber, a first compressor and a circulating tube into an ascending tube. A part of the compressed gas circulating through the tube is recompressed by means of a second compressor and fine iron ore from a stored source is injected into ascending the tube by the recompressed gas by means of a pneumatic fine iron ore conveying system.

Abstract: A high speed tool steel and a manufacturing method therefor are disclosed, in which carbides are formed in the matrix in a uniform manner, thereby obtaining a high toughness and a high abrasion resistance. The high speed tool steel according to the present invention includes a basic composition of W.sub.a Mo.sub.b Cr.sub.c Co.sub.d V.sub.x C.sub.y Fe.sub.z where the subscripts meet in weight %: 5.0%.ltoreq.a.ltoreq.7.0%, 4.0%.ltoreq.b.ltoreq.6.0%, 3.0%.ltoreq.c.ltoreq.5.0%, 6.5%.ltoreq.d.ltoreq.9.5%, 2.2%.ltoreq.x.ltoreq.8.3%, 1.1%.ltoreq.y.ltoreq.2.18%, and 66.52%.ltoreq.z.ltoreq.73.7%. The final structure has carbides uniformly distributed within a martensite matrix, which are mainly MC and M.sub.6 C carbides. The method includes the steps of melting the above-defined alloy composition, gas spraying the melted alloy to form a bulk material, heat treating the bulk material to decompose the M.sub.2 C carbides to stabilize M.sub.6 C carbides and hot working the heat treated bulk material to a desired shape.

Abstract: In a process for producing molten pig iron or liquid steel pre-products, from particulate iron-oxide-containing material by fluidization, the iron-oxide-containing material is prereduced in at least one prereduction stage (7) by aid of a reducing gas and subsequently is reduced to sponge iron in a final reduction stage (8), the sponge iron is melted in a meltdown-gasifying zone (11) under the supply of carbon carriers and an oxygen-containing gas, and a CO- and H.sub.2 -containing reducing gas is produced which is introduced into the final reduction stage (8), is reacted there, is drawn off, subsequently is introduced into a prereduction stage (7), is reacted there, is drawn off, subjected to scrubbing and subsequently is carried off as an export gas and wherein at least a portion of the reacted reducing gas is purified from CO.sub.2, is heated and is used as a recycle-reducing gas for the reduction of the iron-oxide-containing material.

Abstract: In a process for the production of molten pig iron or steel pre-products from fine-particulate iron-cintaining material, in a meltdown-gasifying zone of a melter gasifier (1), under the supply of carbon-containing material and oxygen-containing gas at the simultaneous formation of a reducing gas, in a bed formed of sold carbon carriers, the iron-containing material is melted when passing the bed.

Abstract: The 2-stage fluidized bed furnace for pre-reducing a fine iron ore comprises a first stage fluidized bed furnace for receiving the fine iron ore from a storage hopper, discharging medium/small particle size iron ore to the upper part thereof, and reducing a coarse particle size iron ore while forming a bubbling fluidized bed; a second stage fluidized bed furnace for receiving the medium/small particle size iron ore discharged from the upper part of the first stage and reducing it while forming a turbulent fluidized bed; and a first hot cyclone for collecting the small particle size iron ore contained in the discharged gas from the second stage fluidized bed furnace, the first stage furnace being formed in an upper-narrowed, lower-expanded shape and comprising a narrow, upper portion, a transitional, slanted portion and a wide, lower portion, the second stage furnace being in an upper-expanded, lower-narrowed shape and comprising a wide, upper portion, a transitional, slanted portion and a narrow, lower portio

Abstract: A method for manufacturing a soft magnetic steel sheet is disclosed. The silicon steel sheet is made to undergo a finish treatment so that it can be put to the practical use. The finish treatment method for an Fe-Si silicon steel sheet manufactured by a direct casting method by directly contacting a molten pool to a cooling roll according to the present invention includes the step of pickling the manufactured Fe-Si silicon steel sheet, and carrying out a cold rolling. Then the silicon steel sheet thus cold-rolled is heat-treated at a temperature above 0.5 Tm (Tm: melting temperature of the steel sheet).

Abstract: A device for three-stage fluidized bed for reducing a fine iron ore in accordance with the present invention comprises: a first single-type fluidized bed furnace for drying/pre-heating a fine iron ore in a bubbling fluidized state; a first cyclone for collecting fine iron ore particles entrained in an exhaust gas from the first fluidized bed furnace; a second single-type fluidized bed furnace for pre-reducing the fine iron ore dried/pre-heated in the first fluidized bed furnace; a second cyclone for collecting fine iron ore particles entrained in an exhaust gas from the second fluidized bed furnace; a third twin-type fluidized bed furnace comprising a first cylindrical reaction furnace and a second reaction furnace for finally reducing coarse iron ore particles and medium/fine iron ore particles, respectively, which are pre-reduced in the second fluidized bed furnace; a third cyclone for collecting medium/fine iron ore particles entrained in an exhaust gas from the first reaction furnace of the third fluidize

Abstract: A method for manufacturing coal agglomerates for use in a direct smelting reducing furnace is disclosed, in which a fine coal is agglomerated at a high temperature in a simple manner, or anthracite or low free swelling coal having a low free swelling index is mixed with the fine coal, and the mixture is agglomerated at a high temperature, thereby turning the low quality coal to useful purpose. The present invention is characterized in that a fine coal having a free swelling index of 3.0 or more and a particle size of 8 mm or less, or the fine coal mixed with 70 weight % of anthracite or a low free swelling coal, is maintained at 600.degree. C. or over for 5 minutes or more, thereby manufacturing coal agglomerates for use in a direct smelting reducing furnace.

Abstract: A process for manufacturing nickel chloride is disclosed which is used as the raw material for manufacturing Zn--Ni coated steel plates, for electroless Ni plating industries, for electronic components, and for a high purity chemical additive Ni powder. That is, the invention discloses a process for manufacturing high purity nickel chloride (NiCl.sub.2) by utilizing a waste nickel anode which is obtained from an electroplating factory of a steel manufacturing plant. The process for manufacturing high purity nickel chloride includes the steps of: pre-treating a waste nickel anode to remove impurities adhered on the surface thereof; working the pre-treated waste nickel anode so as to provide an increased specific surface area; putting the worked waste nickel anode into an aqueous hydrochloric acid solution of 10-35% so as for the equivalence ratios of Ni, HCl and NiCl.sub.2 to be 1.0 or more, and dissolving the worked waste nickel anode at a reaction temperature of 20.degree.-80 C.

Abstract: Methods for annealing and pickling high manganese cold rolled steel sheets for use in automobiles and electronic panels in which a superior formability and high strengths are required are disclosed. That is, the invention provides a method for annealing a cold rolled high manganese steel sheet, in which, after cold-rolling a high manganese steel of Fe--Mn--Al--C series, the annealing atmospheric gas is adjusted during an annealing so as to minimize the thickness of a surface oxide layer, and an oxide layer removing agent such as aluminum nitride is spread into the oxide layer, so that the surface oxide layer can be easily removed. The invention further provides a method for pickling a cold rolled high manganese steel sheet, in which the surface oxide layer formed on the cold rolled high manganese steel sheet is uniformly removed with a mild aqueous solution of chloric acid, thereby improving the surface quality of the steel sheet, and saving the pickling facility cost.

Abstract: The annealing conditions of a cold rolled steel sheet are properly controlled so as to form a dense surface oxide layer, thereby improving the adherence strength of the insulating layer on non-oriented electrical steel sheet. The method includes the following steps. A steel slab is prepared which is composed of in weight %: 0.05% or less of C, 3.5% or less of Si, 1.5% or less of Mn, 0.15% or less of P, 0.015% or less of S, 1.0% or less of Al, one or more elements selected from a group consisting of 0.03-0.30% of Sn, 0.03-0.3% of Sb, 0.03-1.0% of Ni and 0.03-0.50% of Cu, the balance of Fe and unavoidable impurities. The steel slab is reheated, hot rolled, pickled after annealing or without annealing and cold-rolled. A low temperature annealing is carried out on the cold rolled steel sheet at a temperature of 750.degree.-850.degree. C. for 30 seconds to 5 minutes under a humid atmosphere having a dew point of 25.degree.-65.degree. C.

Abstract: A reduction apparatus and a method for efficient reduction of fine iron ores of wide grain range comprising serially arranged a drying/preheating furnace, a first reducing furnace for prereduction and a second reduction furnace for final reduction, each working with bubbling fluidized bed and being connected each to a cyclone for capturing iron ore dust contained in the exhaust gases, having each a tapered shape smoothly expanded outwards and thus considerably decreasing elutriation of fine particles, increasing the reduction efficiency and enhancing the utilization of the reducing gas.

Abstract: A three-stage, fluidized-bed-type reduction apparatus and a method for using it for reducing fine iron ores of wide size ranges, improving the gas utilization and reduction degree, reducing the residence time of iron ores, and increasing the prereduction rate of reduced iron. The apparatus includes serially arranged a drying/preheating furnace with a first cyclone connected to it, a primary prereduction furnace with a second cyclone connected to it, a secondary high-gas-velocity reduction furnace for finally reducing only a coarse ore portion of the prereduced iron ores at a bubbling fluidized state while carrying over the medium/fine ore portion of the iron ores, a secondary low-gas-velocity reduction furnace for finally reducing the medium/fine ores forming a bubbling fluidized bed thereof, an inner cyclone installed in the secondary low-gas-velocity reduction furnace, and a third cyclone for capturing dusty ores not captured by the inner cyclone.

Abstract: An apparatus for and a method of melting fine particles containing carbon, capable of uniformly burning and melting the fine particles throughout the entire zone of the combustion flame. The apparatus includes a triple tube structure including an inner oxygen feeding section having an oxygen inlet tube provided with an oxygen feeding passage, a particle feeding section arranged surrounding the inner oxygen feeding section, comprising a particle inlet tube, a feeding tube and a feeding passage, and an outer oxygen feeding section arranged surrounding the particle feeding section, comprising an outer oxygen inlet tube, a feeding tube and a feeding passage. The front ends of the inner oxygen feeding tube, particle feeding tube and outer oxygen feeding tube constitute a nozzle which serves to inject the fine particles fed through the particle feeding tube together with air and/or oxygen flows respectively fed through the inner and outer oxygen feeding tubes to be burned and melted.

Abstract: The present invention relates to a method of determining degrees of an angle between the rotational axes of each of three articulations constituting robot wrist, and more particularly to a method of determining kinematic parameters for robot wrist, wherein a method of determining twist angle between the rotational axes is improved so that robot wrist can orient arbitrarily without regard to position of robot arm when attaching robot wrist having an offset in which the rotational axes of three articulations do not coincide at one point, to the robot arm of an articulated type. According to the present invention, if finding a length l.sub.3 of articulation upper part of robot arm, a virtual length of upper articulation of robot arm (l.sub.3.sup.o) by using offset link length (d.sub.5) of robot wrist, and twist angle (.alpha..sub.4) and twist angle (.alpha..sub.

Abstract: A method for manufacturing a cold rolled steel plate used for enamel applications such as tableware, construction panel, external plate material of microwave oven and gas range, and bathtub, in which an excellent enamel adherence between an enamel layer and a raw steel plate is increased and a formability required for the production of complicated shape is greatly improved and to provide a method for manufacturing a high processing cold rolled steel plate being excellent in enamel adherence. The invention is, in a method for manufacturing an enamel coating cold rolled steel plate by utilizing aluminum killed steel, a method for manufacturing a high processing cold rolled steel plate being excellent in enamel close adhering property in which an aluminum killed steel, in which C: less than 0.01%, Mn: 0.1-0.4%, S: 0.03-0.09%, Ti: 0.04-0.1% and N: less than 0.01% by weight % are contained, and an atomic ratio defined by Ti/(C+N+0.4S) is adjusted to 1.0-2.

Abstract: A duplex stainless steel consisting of a ferrite phase and an austenite phase is disclosed which is superior in the hot ductility, the high temperature oxidation resistance, the corrosion resistance and the impact toughness. The duplex stainless steel is applied to marine facility and the like. The duplex stainless steel which consists of a ferrite phase and an austenite phase is composed of in weight %: less than 0.03% of C, less than 1.0% of Si, less than 2.0% of Mn, less than 0.04% of P, less than 0.004% of S, less than 2.0% of Cu, 5.0-8.0% of Ni, 22-27% of Cr, 1.0-2.0% of Mo, 2.0-5.0% of W, and 0.13-0.30% of N. Or there are further added one or two elements selected from a group consisting of: less than 0.03% of Ca, less than 0.1% of Ce, less than 0.005% of B and 0.5% of Ti. Further, the ratio (Cr.sub.eq /Ni.sub.eq) of the Cr equivalent (Cr.sub.eq) to the Ni equivalent (Ni.sub.eq) is 2.2-3.0. Further, the weight ratio (W/Mo) of the W to Mo is 2.6-3.4.

Abstract: The present invention describes novel cyclic diol derivatives represented by formula I and II: ##STR1## in which Y represents O, S, SO, SO.sub.2, (CH.sub.2).sub.m wherein m is zero or an integer of 1 to 5, or NR.sup.2 group wherein R.sup.a is hydrogen, lower alkyl, lower alkoxycarbonyl, aryl, arylalkyl or acyl;R.sup.1 represents an alkyl or alkylcarbamoyl group;R.sup.2 represents a group having formula T--(CH.sub.2).sub.n --V (X.sup.-)q, wherein T refers to a simple covalent bond, a CO, PO.sub.3.sup.-, C(O)O, or CONR.sup.b group wherein R.sup.b is hydrogen, lower alkyl or acyl;n refers to an integer of from 1 to 10;V represents either (i) the group indicated by formula --.sup.+ NR.sup.5 R.sup.6 R.sup.7 wherein R.sup.5, R.sup.6 and R.sup.7 stands for identical or different lower alkyl group, or two or three of R.sup.5, R.sup.6 and R.sup.7 taken together with the adjacent nitrogen form heterocyclic ammonio group, or (ii) the group indicated by the formula ##STR2## wherein R.sup.

Abstract: A method for agglomerating iron ore particles pre-reduced to produce hot pig iron, wherein hot iron ore particles pre-reduced in the pre-reduction furnace are simply mixed with aluminum powder or aluminum-containing metal powder before being loaded in the smelting reduction furnace so that they will be agglomerated, thereby being capable of not only simplifying the agglomeration, but also eliminating the adverse effect on the quality of ingot iron caused by impurities such as S or P. Aluminum dross, which is a waste, may be used as the aluminum-containing metal powder for agglomerating the iron ore particles. In this case, a reduced energy consumption and disposal of wastes can be achieved.