Abstract: A tracking device is provided with a non-contact type displacement gauge, a positioner which moves a flaw detecting sensor within a plane perpendicular to an axial direction of a pipe or tube, and a positioning controller which controls the positioner.

Abstract: In the production of a seamless steel tube by piercing-rolling a heated billet with a piercing machine to form the billet into a hollow blank, and without reheating the hollow blank, by successively subjecting the hollow blank to elongation-rolling with an elongation-rolling mill and diameter-adjusting rolling by a diameter-adjusting rolling mill, it is made possible to prevent non-uniform longitudinal temperature distribution from occurring in a steel tube after diameter-adjusting rolling and enable energy saving to be accomplished by including a step 1 of measuring a temperature of the hollow blank along a longitudinal direction at the exit of the elongation-rolling mill; and a step 2 of spraying water onto the hollow blank to cool the hollow blank at the entrance of the diameter-adjusting rolling mill according to a measured longitudinal temperature distribution of the hollow blank, whereby the longitudinal temperature distribution of the hollow blank becomes uniform.

Abstract: [Problem to be Solved] Provided are a two-dimensional code reading device and a two-dimensional code reading method for reading a two-dimensional code carved in a member having a substantially circular section orthogonal to the central axis thereof, as well as a method of controlling manufacturing history information using the reading device and a method of manufacturing the member using the control method. [Solution] A concave portion 11 carved in the member on which a two-dimensional code 10 is formed has a pair of a first inclined portion 12 and a second inclined portion 13 which are inclined so as to form an angle ? with respect to a normal-line direction R of a surface of the member.

Abstract: A method for producing a stainless steel three-ply clad sheet for a fuel cell separator comprises heating a source blank and then performing rough rolling, hot rolling and cold rolling thereto, whereby the clad steel sheet for the fuel cell separator or a solid polymer type fuel cell separator thereby is obtained. The source blank for the clad steel sheet is composed of a stainless steel utilizing 0 to 0.3% B as a core component and a stainless steel containing 0.3 to 2.5% B as face component. The source blank is made using face components, a core component, tabs and protectors and performing steps including bonding of the tabs and protectors to the face components, removing portions of the tabs and protectors, piling of the face components to the core component, and further bonding of the face and core components together to form the source blank.

Abstract: An electromagnetic stirrer for stirring molten steel of the liquid core in a width-wise direction of the slab includes an iron core disposed with its length-wise axis along a width-wise direction of slab, and a plurality of exciting coils wound around the outer circumference of and about a length-wise axis of the iron core, wherein two-phase or three-phase alternating current is passed through the coils. The phases of the current in the exciting coils are distributed to impart a stirring flow to the molten that includes flow from the minor sides to the center of the slab or from one minor side to the other minor side with a reversing flow at predetermined time intervals.

Abstract: A lightweight hollow member having excellent stiffness and impact properties and which is suitable for automotive parts due to having a high strength such as at least 780 MPa and a complicated shape is provided. A hollow member 11 has a hollow steel body 14. The body 14 is constituted by a single member at least in the lengthwise direction. The body 14 has a flat cross section having at least a portion with a maximum outer dimension L1 and a portion with an outer dimension L2 shorter than the maximum outer dimension L1. The body 14 has a twisted portion in a portion of its length.

Abstract: A bent metal member which is obtained by bending accompanied by heat treatment of a zinc-based coated metal material and which is suitable for use in components of automobiles due to having a high strength and excellent post-painting corrosion resistance is manufactured. The outer surface of a tubular metal material having on its surface a Zn—Fe alloy coating layer with a coating weight of 30-90 g/m2 per side, an Fe content of 8-20%, and a surface roughness Ra of at most 0.8 ?m is supported at two locations spaced in the axial direction of the metal material so that the material can move in its axial direction, the metal material is heated between the two locations to a temperature range of at least the Ac3 point at a heating speed such that the rate of temperature increase is at least 3.0×102° C. per second while feeding the metal material in its axial direction, holding so that the length of time for which the surface of the metal material is at 8.0×102° C.

Abstract: There is provided a foreign pipe or tube determining method capable of accurately determining a foreign pipe or tube. The foreign pipe or tube determining method in accordance with the present invention includes a step for determining the presence of a foreign pipe or tube by comparing the length of each pipe or tube in a size measuring step with the length of each pipe or tube measured in an actual weighing and length measuring step, which is associated with each pipe or tube in the size measuring step, a step for determining the presence of a foreign pipe or tube by comparing the weight of each pipe or tube calculated in a weight calculating step with the weight of each pipe or tube measured in the actual weighing and length measuring step, which is associated with each pipe or tube in a weight calculating step, and a step for determining the presence of a foreign pipe or tube based on the material of each pipe or tube determined in a material determining step.

Abstract: An ultrasonic testing method relates to a threaded joint of pipes including a pin having an external thread part, a metal seal part, and a shoulder part on an outer peripheral surface, and a box having an internal thread part, a metal seal part, and a shoulder part with the box and pin being fastened together using a lubricant. The method includes transmitting and receiving ultrasonic waves to and from a plurality of locations along an axial direction of the threaded joint in at least one of the internal thread part, the metal seal part, and the shoulder part of the box; detecting echo intensities and reception times of echoes for the plurality of locations; and detecting an abnormal portion in the threaded joint based on a longitudinal axial directional distribution of the echo intensities and longitudinal axial directional distribution of reception times of the echoes.

Abstract: A process for manufacturing a seamless tube which can effectively suppress thickness deviations which are apt to occur in thin-walled seamless tubes is provided. A billet which has been soaked in a heating furnace at a given temperature for a given length of time is subjected to piercing and elongation rolling to form a mother tube, which is then soaked in a reheating furnace at a given temperature for a given length of time and then subjected to sizing to produce a seamless tube with a wall thickness of at most 4 mm. The wall thickness of the tube after sizing is at most 4 mm, the soaking time at the given temperature in the heating furnace is in the range of [billet diameter (mm)×(from 0.14-0.35 )] minutes, and the soaking time at the given temperature in the reheating furnace is in the range of [mother tube wall thickness (mm)×(from 3.0-10.0)] minutes.

Abstract: A lightweight hollow member having a high strength such as at least 780 MPa, a complicated shape which can be applied to automotive parts, a high stiffness, and excellent impact properties, and a manufacturing apparatus and method which can form the hollow member by simple steps and which use relatively small and inexpensive forming equipment are provided. The manufacturing apparatus 10 has a feed unit 11 which feeds a hollow steel material being worked 20 having a closed transverse cross-sectional shape in its lengthwise direction, a support unit 12 which supports the material being worked 20 while it is being fed at a first position A, a heating unit 13 which heats the material being worked 20 at a second position B, a transverse cross-sectional shape modifying unit 14 which carries out working to modify the transverse cross-sectional shape of the material being worked 20 at a third position C, and a cooling unit 15 which cools the material being worked 20 at a fourth position D.

Abstract: An austenitic stainless steel, which consists of by mass %, C?0.02%, Si: 0.01 to 0.50%, Mn: 0.01 to 2.0%, Cr: 24 to 26%, Ni: 19 to 22%, Mo: more than 0.10% to less than 0.50%, N: more than 0.04% to not more than 0.15%, and one or two elements selected from Nb?0.30% and V?0.40%, with the balance being Fe and impurities, and among the impurities P?0.030%, S?0.002% and Sn?0.015%, and satisfies [2.5?36Nb+53V+15N?25.0] and [S+{(P+Sn)/2??5.76×10?4×(36Nb+53V+15N)+0.0267] has excellent corrosion resistance, in particular, excellent intergranular corrosion resistance, and further has excellent crack insusceptibility in a weld heat affected zone. This austenitic stainless steel is a particularly excellent material as structural members for a nuclear power plant.

Abstract: A cold rolled titanium alloy plate with a sufficient cold workability and excellent superplasticity characteristics is provided. The cold rolled titanium alloy plate consists of, by mass %, Al of 2.0 to 4.0% and V of 4.0 to 9.0%, one element selected from Zr of not more than 2.0% and Sn of not more than 3.0% and the balance being Ti and impurities, a ratio of ?/? is not less than 0.3 and not more than 0.6; where “?” is an area of a phase in the plate and “?” is an area of ? phase in the plate, and the plate has an elongation at break in a tensile test conducted at 800° C. exceeds 200%.

Abstract: The present invention provides a lubricant for hot metal working which is capable of inhibiting generation of white scale, attributed to the lubricant, on the surface of a workpiece material and is capable of improving lubricity to obtain favorable appearance of the finished product. The lubricant for hot metal working comprises a silicate compound used for adding to a lubricant composition mainly containing sodium borate.

Abstract: A piercing and rolling plug has a film composed of oxides such as Fe3O4 and FeO and Fe (metal) as being formed on the surface of the base metal by electric arc spraying using an iron wire whose main component is Fe and, owing to this film, a plug excellent in heat-shielding and seizure-preventing effects can be realized and the lifetime of the plug can be prolonged. Further, in regenerating this plug, a film can be re-formed via the steps of shot blasting of the as-used plug in piercing and rolling and electric arc spraying in that order; thus, it is possible to regenerate the plug at low cost and in a short period of time.

Abstract: In this method, the inner surface of a metal pipe containing, by mass percent, 20 to 55% of Cr and 20 to 70% of Ni is subjected to mechanical treatment, the metal pipe is subjected to heat treatment such as to be held in a temperature range of 1050 to 1270° C. for 0.5 to 60 minutes, and thereby an oxide scale layer consisting mainly of Cr is formed on at least the inner surface of the metal pipe. A metal pipe excellent in carburization resistance and coking resistance in a carburizing gas environment can be obtained by the method.

Abstract: The plug is for expanding the inside diameter of the end portion of a metal pipe. Its cross section is a circle, and includes a taper portion and a parallel portion connected to the tail end of the taper portion. The diameter of the taper portion gradually increases from the head end of the taper portion to the tail end of the taper portion where the diameter is D1. The axial distance LR from the point where the diameter D2=D1×0.99 to the tail end where the diameter is D1 satisfies the Expression 22?LR/((D1?D2)/2)?115. The taper angle on the surface where the diameter is D2 is larger than or equal to the taper angle on the tail surface of the taper portion following the point where the diameter is D2. The diameter of the parallel portion is D1.

Abstract: A plug 1 includes a first columnar portion 20, a tapered portion 30, and a second columnar portion 40. The first columnar portion 20 has an outside diameter D1. The second columnar portion 40 has an outside diameter D2 which is larger than the outside diameter D1. The tapered portion 30 is formed between the first columnar portion 20 and the second columnar portion 40. The tapered portion 30 has a tapered surface 31 provided with an outside diameter which is gradually increased from the first columnar portion 20 to the second columnar portion 40, and an axial direction length L. The outside diameters D1 and D2, and the axial direction length L meet the following expressions (1) to (4): 0.25???2.00??(1), 0.06?L/D2?0.8??(2), L/D2?0.3×?+0.575??(3), and L/D2?0.1×???(4) where ?=(D2?D1)/D1×100. Therefore, the cold drawing plug according to the present invention can reduce the tensile residual stress on the outer surface of a metal pipe after the cold drawing.

Abstract: A high-strength seamless steel pipe for oil wells excellent in sulfide stress cracking resistance which comprises, on the percent by mass basis, C: 0.1 to 0.20%, Si: 0.05 to 1.0%, Mn: 0.05 to 1.0%, Cr: 0.05 to 1.5%, Mo: 0.05 to 1.0%, Al: 0.10% or less, Ti: 0.002 to 0.05% and B: 0.0003 to 0.005%, with a value of equation “C+(Mn/6)+(Cr/5)+(Mo/3)” of 0.43 or more, with the balance being Fe and impurities, and in the impurities P: 0.025% or less, S: 0.010% or less and N: 0.007% or less. The seamless steel pipe may contain a specified amount of one or more element(s) of V and Nb, and/or a specified amount of one or more element(s) of Ca, Mg and REM. The seamless steel pipe can be produced at a low cost by adapting an in-line tube making and heat treatment process having a high production efficiency since a reheating treatment for refinement of grains is not required.

Abstract: A threaded joint for steel pipes comprises a pin having male threads and a box having female threads which engage with the male threads. An incomplete thread is formed at the start of the male threads and the incomplete thread has a portion in which the angle ? formed between its crest face and its flank on the side facing a complete thread is an obtuse angle and in which the thread height h from the base of the flank is at least 0.2 mm.