Abstract: A screw surface flaw inspection method and an apparatus therefor, which projects light onto the surface of a screw, the light being scanned axially of the screw, and a detector which picks up the reflected light from the projected surface and sends an output signal to a signal processing circuit to thereby detect the flaw on a basis of time base variation of the intensity of reflected light. The method and apparatus enables the inspection of minute flaws rapidly and exactly.

Abstract: This invention concerns a method of controlling mill-motor speed in a cold tandem mill. During unsteady phases of rolling operation such as threading, rolling speed acceleration and/or deceleration, and tail out with respect to the coil being rolled, mill motors are so controlled as not to perform drooping characteristic action except under certain specific conditions, and at threading phase in particular, motors in individual stands are so controlled as to revolve at a uniformly decreased speed, whereby final gauge control accuracy can be improved with respect to top and bottom end portions of the coil and such troubles as coil cut and the like can be effectively prevented.

Abstract: A metal pipe melt-coated with a thermoplastic synthetic resin using an adhesive composition which contains as major components 5-50 parts by weight of an oil-soluble phenol resin, 5-60 parts by weight of an ethylene copolymer and 5-50 parts by weight of a petroleum hydrocarbon compound having a mean molecular weight in the range of 50,000 to 1,000,000.

Abstract: A method of dephosphorization and desulfurization for molten iron alloy containing chromium, which adds to the bath of molten iron alloy flux comprising alkaline-earth metal oxide and alkaline-earth halide and further adds to the same the predetermined quantity of oxidizing agent, so that simple, highly efficient and economical dephosphorization and desulfurization are performable to produce high-chromium steel or stainless steel of high quality, iron oxide, chromium oxide or oxidizing gas are used as the oxidizing agent.

Abstract: The present invention relates to the manufacture of seamless metal tubes by a cross-roll helical rolling process such as Mannesmann mandrel mill process or by a press piercing process such as Ugine Sejournet process. Shells being worked are subjected to outside-diameter reduction by means of a rotary mill having 3 or 4 rolls, without using internal tools such as plug and mandrel bar, so that wall eccentricity is significantly improved, which fact assured higher quality of finished product.

Abstract: A temperature pattern distribution measuring method and apparatus by which portions of light from parts of an area of an object whose temperature distribution pattern is to be measured, and whose parts are in a predetermined pattern, are passed through first and second optical filters which respectively pass different wavelengths of light. The level of engery passed by the respective filters for the respective portions of light are determined by scanning the light from the filters with a pickup device or devices and, by using the determined energy levels, an arithmetic unit carries out a two-color temperature determining operation for the respective parts of the area for determining the temperature on each part of the area of the object. The temperature pattern of the area of the object can thereby be determined from the temperatures of the parts of the area.

Abstract: The present invention relates to manufacturing process of seamless metal tubes by elongating mill such as Mannesmann mandrel mill. Shells are subjected to rolling operation with main object of wall thickness equalization by means of a rotary mill having 3 rolls without any internal tools such as mandrel bar or plug. This process improves wall eccentricity and enables to decrease the number of billets as materials for tube making.

Abstract: An apparatus for continuous manufacture of butt-welded pipes is constituted by a heating furnace for heating a skelp continuously passed therethrough up to a predetermined temperature less than the butt-welding temperature for the material of the skelp, heaters adjacent the outlet end of the heating furnace and having spaced opposed induction heating coils on opposite sides of the path along which the skelp is passed through the heaters and adjacent the edge portions of the skelp for heating only the edge portions of the skelp discharged from the heating furnace up to the butt-welding temperature. The induction heating coils are such that the electromagnetic coupling between the induction heating coils and the corresponding edge portions of the skelp can be varied to adjust the temperature to which the edge portions are heated.

Abstract: Herein disclosed is a method and apparatus for changing the width of a cast piece during continuous operation. The method comprises stopping pouring a molten metal into a mold, inserting a frame including a pair of opposite side plate members into the mold so that the lower ends of the members are dipped in the molten metal, pouring the molten metal into a cavity defined by said frame, and withdrawing the cast piece together with said frame to obtain a cast piece having a desired width.

Abstract: Herein disclosed is a method for increasing the width of a cast piece during continuous operation. The method comprises stopping pouring a molten metal into a mold, inserting a frame including a pair of opposite side plate members into the mold so that the lower ends of the members are dipped in the molten metal, pouring the molten metal into a cavity defined by said frame, and withdrawing the cast piece together with said frame to obtain a cast piece having a desired width.

Abstract: Disclosed herein is a fully automatic ultrasonic flaw detection apparatus convenient for flaw detection in a weld zone such as found in an welded iron structure. The apparatus includes a scanner for moving a ultrasonic transmitting and receiving probe in directions parallel to and perpendicular to the longitudinal direction of the object to be inspected or the testpiece, and an information processing unit for controlling the action of the scanner and processing received reflected ultrasonic wave flaw detection data. The probe is alternately moved parallel to and perpendicular to the longitudinal direction of the testpiece according to a predetermined scanning routine to perform rough flaw detection and the results of this rough flaw detection are produced as output. When the presence of flaw is detected during this rough flaw detection routine, the probe is returned to a position necessary to perform precision flaw detection of that flaw.

Abstract: A method and apparatus for determining the particle size distribution of particles in a mass of a granular substance. The particles are caused to fall in a stream of separate particles past an irradiated screen, and an instantaneous television picture is taken of the particles and the projected images of the particles are used to measure the projected areas of the particles. Using these areas assuming the average shape of the particles to be substantially a rotational ellipsoid and using a coefficient according to the average configuration of the particles, the particle sizes and their distribution in the mass of particles are calculated.

Abstract: A detector for magnetically detecting flaws on the inner surface of a pipe of magnetizable material comprising a magnetizing assembly having exciting magnets and movable longitudinally along the exterior of the pipe and a detecting assembly movable longitudinally along the interior of the pipe. The magnetizing and detecting assemblies are opposite and close to each other through the wall of the pipe and movable longitudinally of the pipe in a synchronized manner to ensure highly accurate flaw detection.

Abstract: A pipe joint construction comprises a main pipe having a circular section of outer diameter D and one or more branch pipes having a circular section of outer diameter d. The wall thickness To of the main pipe is increased at the interior of the main pipe to a value T at the portion to which branch pipes are welded. The angle .phi. subtended by the portion of increased thickness at the center of the main pipe is determined by the following relationship, that is,1>.phi./2.pi..gtoreq.(.alpha..sup.2 /k)(d/D).sup.1/4 (D/T).sup.1/2 (T/To)where .alpha. represents a rigidity ratio and k is a constant.

Abstract: This invention relates to a method of controlling blast furnace operation by manipulating the following variables: oil injection rate, blast moisture, blast oxygen rate, blast rate blast temperature and ore/coke ratio.

Abstract: A detector for magnetically detecting flaws on the inner surface of a pipe of magnetizable material comprises a magnetizing assembly having exciting magnets and movable longitudinally along the interior of the pipe and a detecting assembly movable longitudinally along the exterior of the pipe. The magnetizing and detecting assemblies are opposite and close to each other through the wall of the pipe and movable longitudinally of the pipe in a synchronized manner to ensure highly accurate flaw detection.

Abstract: A bolt and nut unit coated with lubricant comprising graphite and/or molybdenum disulfide, an ethylene-vinyl acetate copolymer and a fatty acid or a metallic soap thereof. This lubricant has low temperature sensitivity, and the bolt and nut unit coated therewith can be tightened precisely into position with a constant torque regardless of variations in ambient temperature and humidity.

Abstract: A packing for use in a steel-pipe hydraulic testing apparatus, consisting of: an annular body having an annular cut in its inner peripheral portion; a plurality of backing pieces fastened to the wall of the annular cut at a given circumferential spacing and directed in the radial direction; and a plurality of adapter pieces embedded in the inner peripheral walls of the annular body of the packing at a given circumferential spacing and exposed to the annular cut, so that the aforesaid plurality of backing pieces may be each slidable on the surfaces of a pair of adjoining adapter pieces. This packing is contracted due to a hydraulic pressure being applied to the outer periphery of the body of the packing, and as a result the respective adapter pieces will slide on the surfaces of the adapter pieces in the circumferential direction of the packing.

Abstract: There are applied in layers on the surface of a metal pipe, a rapid hardening and cure type corrosion preventive material consisting essentially of isocyanate terminated polyurethane prepolymer, amine base hardener and petroleum resin, and a reinforcing material consisting of silica sand, blast furnace slag or the like. Thus there are provided a plurality of coatings or layers on the metal pipe, which are excellent in impact resisting and corrosion preventive properties.

Abstract: A continuous production line is divided into a plurality of zones, with each of which there is associated a presettable counter. An anticipated length of a material, which has been calculated from information regarding the material before welding, is converted into a given number of pulse signals, which in turn are preset in the counter, with its timing being shifted a zone to zone distance. Long materials which have been sequentially joined by welding into a continuous length of material are fed into the production line, and the length of material actually fed is detected by means of a feed length gage, and an output of the gage is converted into a pulse signal. The length of the material actually fed is substracted from the anticipated length of the material, i.e., the preset count value, as the material is being fed. Thus, it is presumed that a welded joint across the length of material is present in the zone where a preset count value becomes zero as a result of the aforesaid subtraction.