Abstract: A sealed threaded connection with a male end and a female end, the male end having a sealing surface and finishing in a terminal surface orientated transversely to the axis of the connection. The female end has a threaded zones inclined in accordance with a conical generatrix forming an angle of taper alpha; with the axis of the connection, sealing surface being cooperating with the sealing surface of the male end along a radially interfering contact zone, and finishing in a terminal surface which is transversely orientated, the tangent at the contact zone of the sealing surface being inclined along a line forming an angle beta; with the axis of the threaded connection, wherein the inclination defined by the conical generatrix relative to the threaded zones is in a direction opposite to the inclination defined by the tangent at the contact zone of the sealing surface.

Abstract: To form a through hole at one portion of a side wall, of an expanded portion made by plastically deforming one part of a metal tube radially outward, in a portion where the plate thickness gradually changes, a slide tool is withdrawn from inside a punch hole while applying hydraulic pressure to the inside of the side wall. At the instant of commencing withdrawal of the slide tool, the degree of progress in the shearing for the portions of the side wall matching with the two side edges of the punch hole is made different. Then, the timing for moving from shearing to rupture is made to coincide, so that of the side wall, the portions matching with the punch hole, are made reliably into a blank, and are extracted from the side wall.

Abstract: To provide an austenitic stainless steel which has an excellent high-temperature corrosion thermal fatigue cracking resistance. An austenitic stainless steel containing, by mass %, Cr: 15.0 to 23.0%, and Ni: 6.0 to 20.0%, wherein a near-surface portion is covered with a worked layer with high energy density having an average thickness of 5 to 30 ?m.

Abstract: Modified natural graphite particles intended for forming a negative electrode material for a nonaqueous electrolyte secondary battery are characterized by having a circularity of at least 0.93 and at most 1.0 and a surface roughness of at most 1.5% with respect to the length of the particles. These modified natural graphite particles are obtained by a manufacturing method including a step of applying an impact force to natural graphite particles for pulverization and spheroidization to obtain intermediate particles having a circularity of at least 0.93 and at most 1.0, and a step of carrying out surface smoothing of the resulting intermediate particles by mechanical grinding treatment to obtain the modified natural graphite particles.

Abstract: It is an object of the present invention to provide a mandrel bar cleaning facility capable of effectively suppressing carburization generated on the inner surface of a pipe or tube while the pipe or tube is elongated and rolled without hindering an operation. A mandrel bar cleaning facility of the present invention cleans a mandrel bar B which is pulled out of a mandrel bar conveying line after being used for elongating and rolling a pipe or tube in a mandrel mill. The mandrel bar cleaning facility is provided with conveying devices that convey the mandrel bar B in the axial direction while revolving the mandrel bar B in the peripheral direction, and cleaning devices that are arranged oppositely to the side of the mandrel bar B conveyed by the conveying devices and jet high-pressure water having a water pressure of 0.2 to 150 MPa (preferably, 20 to 150 MPa) toward the outer surface of the mandrel bar B.

Abstract: A threaded connection including first and second tubular components including respective male and female ends including a distal surface and a threaded zone. The threaded zone of the male end is threaded into the threaded zone of the female end. The threaded zones include respective male and female threads having increasing width from the distal surface and including load flanks having negative angles over at least a portion of their radial dimension, and stabbing flanks, with a radial clearance in the connected state between crests of the male threads and roots of the female threads and/or between crests of the female threads and roots of the male threads, with an axial clearance in the connected state between the stabbing flanks of the male and female threads. The distal surface of the male and/or female end is brought into axial abutting contact against a corresponding abutment surface.

Abstract: In a mold for continuously casting a round billet with a curved type continuous casting apparatus, assuming that D0 (m) is an inner diameter at a lower mold edge and R0 (m) is a curvature radius of an outer curvature side at the lower mold edge, when a rate of change Tp (%/m) in mold inner diameter per unit length along a casting direction is expressed by Formula 1, and when a rate of change Rp (%/m) in curvature radius of an outer curvature side per unit length along the casting direction is expressed by Formula 2, the rate of change Tp in mold inner diameter and the rate of change Rp in curvature radius satisfy a relationship expressed by Formula 3; Tp=(1/D0)×(dD/dx)×100(%/m)??Formula 1 Rp=(1/R0)×(dR/dx)×100(%/m)??Formula 2 where D in Formula 1 is a mold inner diameter at a distance x away from an upper mold edge and R in Formula 2 is a curvature radius of the outer curvature side at the distance x, Rp=(Tp/2)×(D0/R0)??Formula 3 Uniform and good contact is obtained between the billet and a mold inner pe

Abstract: A bent member having a bent portion with an extremely small bend radius is manufactured by supporting a rectangular tube by a first support means disposed at a first position A while performing relative feeding of the rectangular tube in its lengthwise direction, locally heating the rectangular tube by a heating means disposed at a second position B, cooling the rectangular tube by a cooling means disposed at a third position C, and at the time of working, applying a shear force to the heated portion of the rectangular tube with a shear force applying means 14 disposed in a downstream region D by moving the device 14 two-dimensionally or three-dimensionally simultaneously in the feed direction of the rectangular tube and in a direction generally parallel to a transverse cross section in the lengthwise direction of the rectangular tube which was heated by the heating means.

Abstract: A method capable of stably manufacturing a SiC single crystal in the form of a thin film or a bulk crystal having a low carrier density of at most 5×1017/cm3 and preferably less than 1×1017/cm3 and which is suitable for use in various devices by liquid phase growth using a SiC solution in which the solvent is a melt of a Si alloy employs a Si alloy having a composition which is expressed by SixCryTiz wherein x, y, and z (each in atomic percent) satisfy 0.50<x<0.68, 0.08<y<0.35, and 0.08<z<0.35, or ??(1) 0.40<x?0.50, 0.15<y<0.40, and 0.15<z<0.35.??(2) x, y, and z preferably satisfy 0.53<x<0.65, 0.1<y<0.3, and 0.1<z<0.3.

Abstract: Provided are an ultrasonic testing method and an ultrasonic testing apparatus capable of accurately detecting flaws present in a weld zone of a test object, such as a welded pipe, regardless of the position of the flaws. An ultrasonic testing apparatus 100 includes an ultrasonic probe 1 which is provided with n (n?2) transducers 11 arranged along a direction orthogonal to the weld line of a weld zone P1 of a test object P and is arranged so as to face the weld zone, and transmission/reception control means 2 which selects m (n>m?1) transducers from the n transducers, causes the selected transducers to transmit and receive ultrasonic waves to and from the weld zone, and switches the selected transducers one after another.

Abstract: There is provided a production method of an internally ribbed steel tube, capable of forming spiral ribs stably so as to reduce troubles at the time of cold drawing for forming the spiral ribs of the steel tube. In this production method, the spiral ribs can be formed stably so as to reduce troubles at the time of cold drawing for forming the spiral ribs by straightening bends of a blank tube before the cold drawing for forming the spiral ribs, by optimizing the direction of the spiral rib formation after the bend straightening, and by correcting the drawing schedule depending on the blank tube. The obtained internally ribbed steel tube is well applicable to an increased capacity and a higher temperature/higher pressure operation of a boiler because the steel tube is provided with high formability and excellent quality as a boiler steel tube.

Abstract: A method of manufacturing a 13Cr steel pipe which satisfies a hardness (HRC) of at most 22 with 13Cr grade L80 of American Petroleum Institute (API) standards, which is an indicator of a high strength, high yield ratio, and good corrosion resistance, is provided. A steel billet having a chemical composition comprising, in mass percent, C: 0.15-0.21%, Si: 0.16-1.0%, Mn: 0.35-1.0%, Cr: 10.5-14.0%, P: at most 0.020%, S: at most 0.0050%, Al: 0.025-0.050%, and a remainder of Fe and impurities is subjected to hot working with a finishing temperature of 800-960° C. to form a mother pipe, which is immediately quenched at a cooling rate of at least air cooling and then tempered by heating.

Abstract: A seamless steel pipe produced by heating a steel billet, which has a chemical composition C: 0.15 to 0.20%, Si: not less than 0.01% to less than 0.15%, Mn: 0.05 to 1.0%, Cr: 0.05 to 1.5%, Mo: 0.05 to 1.0%, Al?0.10%, V: 0.01 to 0.2%, Ti: 0.002 to 0.03%, B: 0.0003 to 0.005% and N: 0.002 to 0.01%, further optionally one or more of Ca, Mg and REM in a specific amount, under the provision that the conditions “C+(Mn/6)+(Cr/5)+(Mo/3)?0.43” and “Ti×N<0.0002?0.0006×Si” are satisfied, with the balance being Fe and impurities, wherein P?0.025%, S?0.010% and Nb<0.005% among the impurities, to a temperature of 1000 to 1250° C. followed by pipe-making rolling at a final rolling temperature 900 to 1050° C., and then quenching the resulting steel pipe directly from a temperature not lower than the Ar3 transformation point followed by tempering at a temperature range from 600° C.

Abstract: A lubricant for hot-rolling tools in which an oxide-based laminar compound such as potassium tetrasilicic mica, sodium tetrasilicic mica, vermiculite, and bentonite, a boric acid compound such as boric acid, potassium borate, and sodium borate, and graphite are dispersed and dissolved in water, and in which the blending proportion of the oxide-based laminar compound to the boric acid compound is, in mass ratio, 10:90 to 70:30, and the content of the graphite is 1.0 to 4.5%. Applying this lubricant on the surface of the mandrel bar at the time of mandrel mill rolling enables a lubricating film to be formed on the surface of the bar and to exert excellent seizure resistance, and also allows the lubricant to be immune from remaining in the inner surface of tube.

Abstract: A bent member having excellent dimensional accuracy is manufactured by stably forming a high temperature portion uniformly in the circumferential direction of a steel tube and in a narrow region in the axial direction of the steel. The bent member is manufactured by supporting a steel tube at a first position while feeding it, performing induction heating of the steel tube at a second position with an induction heating coil, cooling the steel tube at a third position to form a high temperature portion which moves in the axial direction of the steel tube, and three-dimensionally varying the position of a gripping mechanism for the steel tube in a region to apply a bending moment to the high temperature portion.

Abstract: There is provided a steel pipe for steam injection having high yield stress even at 350° C. The seamless steel pipe for steam injection according to the present invention has a chemical composition comprising, by mass percent, C: 0.03 to 0.08%, Si: 0.05 to 0.5%, Mn: 1.5 to 3.0%, Mo: more than 0.4 to 1.2%, Al: 0.005 to 0.100%, Ca: 0.001 to 0.005%, N: 0.002 to 0.015%, P: at most 0.03%, S: at most 0.01%, and Cu: at most 1.5%, the balance being Fe and impurities. The seamless steel pipe is manufactured by being water cooled after hot working and by being quenched and tempered.

Abstract: A seamless steel pipe for line pipe having high strength and high toughness contains, by mass percent, C: 0.02 to 0.10%, Si: at most 0.5%, Mn: 0.5 to 2.0%, Al: 0.01 to 0.1%, P: at most 0.03%, S: at most 0.005%, Ca: at most 0.005%, and N: at most 0.007%, and further contains at least one selected from a group consisting of Ti: at most 0.008%, V: less than 0.06%, and Nb: at most 0.05%, the balance being Fe and impurities. A carbon equivalent Ceq defined by Formula (1) is at least 0.38, a content of Ti, V and Nb satisfies Formula (2), and the size of carbo-nitride containing at least one of Ti, V, Nb and Al is at most 200 nm, Ceq=C+Mn/6+(Cr+Mo+V)/5+(Ni+Cu)/15??(1) Ti+V+Nb<0.06??(2).

Abstract: An induction heating coil for stably heating a steel tube which is being fed in its axial direction without rotating, the heating being uniform in the circumferential direction and in a narrow range in the axial direction has at least two 1-turn coils in the form of a first turn coil body and a second turn coil body. The inner peripheral length Ln (the non-effective coil length) where the effective number of coil turns is less than the total number of coil turns when the coil is projected in the axial direction and the inner peripheral length L0 of the projected coil bodies (the inner coil length) satisfy Ln/L0<0.05. First and second coil bodies have insulating portions on their connecting portions, and the insulating portions are present in locations separated by a central angle of 5-45° measured from the center of the coil bodies.

Abstract: A brake lining for a railroad car has a frictional surface on a brake disc that is pressed by a brake caliper. Friction bodies are pressed against the frictional surface of the brake disc and a back plate is mounted to the caliper to support the friction bodies. Each of the friction bodies is formed with a friction material which contacts the brake disc frictional surface, and has a base plate attached on the back plate side of the friction material. The base plate has a protrusion formed on its back side. On the friction body side of the back plate there is formed a groove which contacts the protrusion formed on the base plate. A disc spring or a spherical-seated structure is disposed between the base plate of each friction body and the back plate. Friction bodies are prevented from rotating at their attached places, without adding new components.

Abstract: A defect inspecting apparatus includes a first light source, a first image capture device that receives the reflection light emitted from the first light source and reflected by the outer peripheral surface of a lip part to grab the image of the outer peripheral surface of the lip part, a second light source, a second image capture device 8 that receives the reflection light emitted from the second light source and reflected by a load face to grab the image of the load face, a third light source, a third image capture device that receives the reflection light emitted from the third light source and reflected by a thread bottom face inspection zone 106 to grab the image of the thread bottom face inspection zone, and an inspection device for inspecting defects by processing the captured images grabbed by the first to third image capture devices.