Abstract: A method for mounting a ring-shaped construction on a ship stern in front of a propeller which comprises fixing a plurality of pieces at a predetermined distance along a periphery of a ring-shaped construction, marking the points respectively on a plurality of said pieces which are located in a same distance from the center of said ring-shaped construction, and mounting said ring-shaped construction to said ship stern. In this process, centering so that the circular locus of the beam emitted from a projector being rotated around the rotating axis of a propeller passes over said marked points of a plurality of pieces fixed to said ring-shaped construction, the settling position of said ring-shaped construction is adjusted.

Abstract: An artificial island for installing oil drilling equipment in ice covered sea areas, comprising barricades against ice which surround oil drilling equipment installed in ice covered sea-water and whose respective top portions are projected above the surface of the sea-water, means provided at the bottom portions of the barricades so as to fix them to the sea-bottom, and inclined ice breaking walls provided at the outer sides of the barricades.

Abstract: A welding method in which two metal bars are disposed such that the opposing ends of these bars are placed in a welding mold with a predetermined welding gap preserved therebetween, and are jointed to each other by filling the space formed between the opposing ends of the bars and the inner surface of the welding mold with a molten welding metal. Also, disclosed is a welding apparatus having a welding gap setting device for placing the metal bars with a predetermined welding gap therebetween and an arc welder for jointing the bars by filling the welding gap with molten welding metal.

Abstract: The present invention relates to a ship with structural improvements which prevent factors causing an increase in the horsepower required for propulsion or an increase in propeller cavitation, hull vibration and noise, all of which result from the water turbulence and nonuniformity of flow field along the stern caused by corpulence of ship, and the present invention provides such a ship with a structural improvement comprising having a ring-shaped construction directly attached to the hull on each of the ship's stern and in front of the propeller.

Abstract: A catalytic reactor for reducing nitrogen oxide (NO.sub.x) contained in exhaust gas under the presence of ammonia is provided, wherein tubular catalyst units each being a ring shape in cross-section are disposed in spaced apart relationship from one another in the cross-section of the flow path of the exhaust gas in a manner that tubular axes thereof are in parallel with the direction of gas flow within a reaction vessel through which the exhaust gas containing nitrogen oxide (NO.sub.x) and ammonia flows, said catalyst units each being secured to the interior of the reaction vessel at least as two points in the longitudinal direction by support means.

Abstract: A working platform for oil drilling operations in ice covered sea areas, which essentially comprises oil drillig equipment, an oil drilling pipe connecting the oil drilling equipment to the sea bottom, and a floating frame having a buoyancy and a strength enough to stand the pressure of an ice covering and being movable in accordance with movement of ice covering; the floating frame is disposed surrounding such a surface area of the ice covered sea as lying around the oil drilling pipe, whereby the pipe is protected by the floating frame against action of the pressure of ice covering during oil drilling operations.

Abstract: A high-speed bevel gear transmission system for transmitting power from an input shaft to a pair of parallel outputs shafts the axes of which intersect each other. The input shaft has a pair of driving bevel gears which are fixedly mounted thereon such that the driving bevel gears face in opposite directions and which have the same number and size of teeth spirally arranged in the opposite directions each other. The output shafts are supported on angular contact ball bearings and have two driven bevel gears fixedly mounted thereon which are engaged with the driving bevel gears. The speed transmission ratio of the output shafts to the input shaft is 1.45:1 to 0.476:0.1, the relation between a pressure angle .alpha. and helix angle .beta. of the driving bevel gears and driven bevel gears, and a pitch cone angle .delta. of the driven bevel gears are defined by the formula, R=[(tan.alpha..multidot.sin .delta.)/cos .beta.]-tan.beta..multidot. cos .delta. when 0.324.ltoreq.R.ltoreq.0.1.

Abstract: A process for the thermal cracking of hydrocarbons by feeding them into a line together with a fused salt, which comprises: feeding a fused salt mixed with steam into a reaction tube of a thermal cracking furnace of external heating type and further feeding raw hydrocarbons mixed with steam into said reaction tube to thermally crack the raw hydrocarbons; quenching the resulting fluid mixture of the cracking products, fused salt and steam in a quenching device, then dividing the fluid mixture into the fused salt and a gaseous substance, removing sludge and, if necessary, sulfur compounds from thus separated fused salt and recirculating the fused salt to the reaction tube and the quenching device; and dividing thus separated gaseous substance into an oil containing coke, tarry substances and fused salt mist and the intended cracking gas, and subjecting the oil to treatment with steam to convert the coke and tarry substance in the oil into water gas or to partial burning treatment with air or oxygen to divide th

Abstract: An axial-flow turbine which is driven by a working fluid which contains dust and moisture is disclosed. The turbine has stator blade means and rotor blade means, and a working fluid exit angle of a first-stage stator blade means is smaller than that of the second-stage stator blade, wherein the absolute exit velocity of the working fluid from the first stage stator blade means is smaller than that of the second stage stator blade means, whereby the flow of the working fluid has the same directional vortical flow with the turbine shaft as the axis of the vortex and dust fouling is checked particularly in connection with the first-stage stator blade means.

Abstract: A method of automatic underwater painting over metal surfaces of ships and offshore constructions is disclosed, which broadly comprises the steps of freely running a painting machine along the metal surface, sealably attaching the machine onto the metal surface of a location as desired and thereby forming a painting chamber over the metal surface for painting, transferring the water within the painting chamber to a ballast tank of the machine, and while paint jetting nozzles of the machine being reciprocated within the painting chamber, jetting a paint to effect an even painting over a wide area of the metal surface. The painting machine, which is also disclosed, includes an improved maneuvering mechanism, improved buoyancy adjusting mechanism, improved waterproof electromagnet, nozzle driving mechanism and paint circulation system.

Abstract: The present invention relates to a method and apparatus for recovering energy from a blast furnace exhaust gas by utilizing an axial-flow turbine. According to the method of the present invention, a blast furnace exhaust gas is first passed through a wet scrubber to remove dusts and form a saturated gas, and low temperature water is sprayed to the saturated gas to add condensed mists to the gas. According to this method, adhesion of dusts to a turbine can be effectively prevented. When large nozzles and large moving blades are used for the turbine for use in practising this method, adhesion of dusts and erosion of nozzles and moving blades can be effectively prevented.

Abstract: A process for the production of microbial protein and lipid from vegetable carbohydrates including starch by culture of a microbe, which comprises a combination of the steps of liquefying starch with a dextrinogenic enzyme in a liquefaction tank, effecting simultaneous saccharification and culture of the microbe in a fermentation tank by aseptically adding a saccharogenic amylase to the culture medium produced in the liquefying step, and separating the cultured microbial cells and lipid from the culture medium.

Abstract: A rotary ice-breaking body having a spiral rotary blade is attached to a structure for use in icy waters at a part falling in contact with an ice lump or ice floe. The rotary blade is actuated to bite into the ice lump and to lift up or press down the ice lump. The ice lump is broken by the flexural stress and the structure is protected from influences of the ice lump. One rotary ice-breaking body may be disposed to constitute the outer periphery of the structure. Alternately, a plurality of rotary ice-breaking bodies may be disposed to surround the structure so that they are driven and rotated simultaneously or independently.

Abstract: Hydrocarbons are cracked in the presence of a mist of molten salt containing of basic compounds of alkali and alkaline earth metals and mixtures thereof, the amount of the molten salt to hydrocarbon being, by weight, from 0.01:1 to 10:1 followed by quenching at a temperature not lower than the melting point of the molten salt, and separating the cracked gas from the molten salt.

Abstract: A water collecting and distributing apparatus capable of collecting filtrate, distributing raw water, supplying back wash water and dispersing scouring air, which is disposed in a lower portion of a high speed filter basin, is disclosed. This apparatus comprises a plurality of blocks regularly arranged in the bottom portion of the filter basin, each block having a flow passage for air and water in the central portion thereof and a water dispersing chamber located adjacent to the flow passage. A communication hole is formed in a partition wall between the flow passage and the water dispersing chamber, and an injection hole is formed in each of the top wall of the flow passage and the top wall of the water dispersing chamber. The numbers and diameters of the communication holes and injection holes in the blocks and positions of these holes are arranged so that a certain relation is established among them. In each block, the flow passage is formed to have a trapezoidal sectional shape.

Abstract: Disclosed are ice-breaking units for ships adapted to be installed at the bow and/or bottom portion of the ship's hull, consisting of two ice-breaking units each of which can be reversibly driven independently of each other, for performing ice-breaking and/or propulsion of the ship. The ice-breaking unit has a screw-like body having a spiral blade wound thereabout. The ice-breaking units may be disposed at the bow portion, at both sides of the longitudinal center line of the ship, in parallel with or normal to the latter, or may be arranged to have a propulsion portion and an ice-breaking portion, respectively. The two screw-like bodies may be driven simultaneously in the same direction or reversed, or may be rotated in the opposite directions, to provide thrusts to move the ship in any direction of ahead/astern and port/starboard.

Abstract: Method and apparatus for recovering heat energy and kinetic energy of a gas discharged from the top of a blast furnace effectively as electric energy or other energy by a turbine and a control mechanism. An exhaust gas is supplied to a septum valve and then into a turbine connected in parallel, and the capacity or design value of the turbine is set at a mean value of the total flow rate of the exhaust gas varying with the lapse of time during the normal steady operation of the blast furnace. When the total flow rate of the exhaust gas is lower than the mean value, all the exhaust gas is supplied to the turbine to recover the energy of the exhaust gas and the top pressure of the furnace is controlled by a governor valve regulating the speed of the turbine.

Abstract: A device for protecting a turbine driven by an exhaust gas of a blast furnace from a high temperature gas generated and discharged when the blow-out phenomenon takes place in the blast furnace is disclosed. In this protective device, occurrence of the blow-out phenomenon is detected, and cooling water is sprayed in an exhaust gas or in the turbine to lower the temperature of the gas, or cooling water is directly sprayed to a part of a material which readily undergoes thermal degradation to cool the material.

Abstract: A hydraulic hammer wherein the reciprocal motion of a drill-striking piston is operated by means of a spool valve for switching hydraulic pressure to a double-acting cylinder depending upon the position of the piston. The hydraulic hammer further includes a self starter means which assures activation of the hammer whenever hydraulic pressure is applied to the hydraulic hammer and a means for compensating for variations in boring conditions such that energy is efficiently delivered by the drill striking piston.

Abstract: In a method for recovering energy of an exhaust gas from a blast furnace as electric energy by introducing the total flow rate of the exhaust gas into a turbine, the efficiency of recovery of the power energy is enhanced by controlling the attachment angle of stationary blades of the turbine so that the furnace top pressure might be maintained at a predetermined level.