Abstract: A first thread feature is measured by detecting with an optical sensor 2 light that reaches from a light source 21 located on the opposite side of a pipe axis and runs substantially in parallel to thread grooves A4. A contact probe 31 of a contact sensor 3 is contacted with a thread flank surface A8 to detect the space coordinates of the contact probe 31 at the time of contact, so that a second thread feature is measured. The first and second thread features thus detected are combined with each other by a processor 4, and thread features of the thread provided as a measurement object are thereby calculated.

Abstract: A two-dimensional code reading device 20 is provided with image pickup device 22 which receives light reflected from either of a first inclined portion 12 and a second inclined portion 13 in a direction forming an angle ? satisfying expression (1) with respect to the normal-line direction R, and light source 21 which irradiates either of the inclined portions from a direction forming an angle ? satisfying expression (2) with respect to the normal-line direction R: 30°???35°??(1) ??=??180°+?+2???(2) where ? is less than 90°, ?? is not less than ?10° but not more than 10°, and ? and ? are angles in a turn direction reverse to a turn direction at which either of the inclined portions forms the angle ? with respect to the normal-line direction R.

Abstract: A dimension measuring device 100 in accordance with the present invention includes an end face following mechanism 1 that butts against an end face E of a long material, a dimension measuring mechanism 2 for measuring the dimensions of the long material, and a pushingly moving mechanism 3 for pushingly moving the end face following mechanism toward the end face of the long material. The end face following mechanism includes a plurality of contact sensors for detecting a contact state, and is turnable around two axes intersecting at right angles with each other. The pushingly moving mechanism pushingly moves the end face following mechanism into the state in which the plurality of contact sensors detect that the end face following mechanism butts against the end face of the long material.

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 martensitic stainless steel pipe, which comprises specified quantities of C, Si, Mn, P, S, Cr, Ni, Al, N, Cu, Ti, V, Mo, Nb, B and Ca, and the balance being Fe and impurities, has satisfactory toughness at a high strength of 650 MPa or more by yield strength and also excellent hot workability. Therefore, it can be used as a high-strength martensitic stainless steel pipe for carbon dioxide gas corrosion resistant use, to be used in oil and/or gas well environments containing no hydrogen sulfide but carbon dioxide gas. This high-strength martensitic stainless steel pipe is an inexpensive martensitic stainless steel pipe, which does not require an addition of large quantities of expensive elements such as Ni and Mo, and moreover does not require the control of the content of P to a value less than 0.010% by mass.

Abstract: A first thread feature is measured by detecting with an optical sensor 2 light that reaches from a light source 21 located on the opposite side of a pipe axis and runs substantially in parallel to thread grooves A4. A contact probe 31 of a contact sensor 3 is contacted with a thread flank surface A8 to detect the space coordinates of the contact probe 31 at the time of contact, so that a second thread feature is measured. The first and second thread features thus detected are combined with each other by a processor 4, and thread features of the thread provided as a measurement object are thereby calculated.

Abstract: A dimension measuring device 100 in accordance with the present invention includes an end face following mechanism 1 that butts against an end face E of a long material, a dimension measuring mechanism 2 for measuring the dimensions of the long material, and a pushingly moving mechanism 3 for pushingly moving the end face following mechanism toward the end face of the long material. The end face following mechanism includes a plurality of contact sensors for detecting a contact state, and is turnable around two axes intersecting at right angles with each other. The pushingly moving mechanism pushingly moves the end face following mechanism into the state in which the plurality of contact sensors detect that the end face following mechanism butts against the end face of the long material.

Abstract: The production history information management apparatus 100 comprises: machining an identifier for identifying a pipe or tube in a region of the pipe or tube on which thread cutting is to be performed before an initial production process is performed among production processes which are management targets of the production history information; reading the identifier machined on the pipe or tube before each of the production processes is performed or while each of the production processes is performed; management for storing the production history information of the pipe or tube obtained in each of the production processes and the identifier read from the pipe or tube while the production history information and the identifier are associated with each other; and thread cutting for removing the identifier machined on the pipe or tube in the process of performing the thread cutting on the end portions of the pipe or tube among the production processes which are management targets of the production history inform

Abstract: This invention relates to a method of manufacturing a martensitic stainless steel. The method comprises the following steps (a) to (c): (a) preparing a steel having a chemical composition consisting of, by mass %, C: 0.003 to 0.050%, Si: 0.05 to 1.00%, Mn: 0.10 to 1.50%, Cr: 10.5 to 14.0%, Ni: 1.5 to 7.0%, V: 0.02 to 0.20%, N: 0.003 to 0.070%, Ti: not more than 0.300% and the balance Fe and impurities, and P and S among impurities are not more than 0.035% and not more than 0.010% respectively, and that it also satisfies the following equation: ([Ti]?3.4×[N])/[C]>4.5 wherein [C], [N] and [Ti] mean the content (mass %) of C, N and Ti, respectively, (b) heating the steel at a temperature between 850 and 950° C., (c) quenching the steel, and (d) tempering the steel at a temperature between Ac1?35° C. and Ac1+35° C. and in a condition of not more than 0.5 of the value of variation ?LMP1 in the softening characteristics LMP1, which is defined by the following equation: LMP1=T×(20+1.

Abstract: The present invention provides a martensitic stainless steel seamless pipe and a method of making, wherein the pipe has minimal inner surface defects and prevents delayed fracture generation in the impact-worked portions. The pipe comprises C: 0.15 to 0.22%, Si: 0.1 to 1.0%, Mn: 0.10 to 1.00%, Cr: 12.00 to 14.00%, P: 0.020% or less, S: 0.010% or less, N: 0.05% or less, O(Oxygen): 0.0060% or less, at least one alloying element selected from V, Nb and Ti of 0.005 to 0.200% and B of 0.0005 to 0.0100%, and the balance Fe and impurities, wherein either the following inequalities (1), (2), (4) and (5) or the following inequalities (1), (3), (4) and (5) are satisfied: C*+10N*?0.45,??(1) H1??0.003(C*+10N*)+0.0016,??(2) H2??0.0018(C*+10N*)+0.00096,??(3) Cr*?9.0,??(4) S?0.088N*+0.00056,??(5).

Abstract: A plug member can be mounted to the end of a pipe and removed therefrom by automated operation. A mounting and dismounting device 21 for mounting and dismounting a plug member 11 with respect to an oil country tubular good P. The plug member 11 comprises an outer tube 12 having seal portions 16a and 16b and a circumferential groove 12a, a shuttle 13, a cap 14, and a shuttle biasing spring 15 secured to the cap 14 and the shuttle 13. The mounting and dismounting device 21 comprises a tubular holding body 22, a rod 23 which has a conical end portion 23a and which is disposed so as to move inside the tubular holding body 22, and moving means 24 and 25 which allow the tubular holding body 22 and the rod 23 to independently move. The tubular holding body 22 has ball-receiving holes 22a into which fit balls 26 which engage with the circumferential groove 12a.

Abstract: The production history information management apparatus 100 comprises: machining means 1 for machining an identifier for identifying a pipe or tube in a region of the pipe or tube on which thread cutting is to be performed before an initial production process is performed among production processes which are management targets of the production history information; reading means 2 for reading the identifier machined on the pipe or tube before each of the production processes is performed or while each of the production processes is performed; management means 3 for storing the production history information of the pipe or tube obtained in each of the production processes and the identifier read with the reading means from the pipe or tube while the production history information and the identifier are associated with each other; and thread cutting means 4 for removing the identifier machined on the pipe or tube in the process of performing the thread cutting on the end portions of the pipe or tube among the p

Abstract: A martensitic stainless steel pipe, which comprises specified quantities of C, Si, Mn, P, S, Cr, Ni, Al, N, Cu, Ti, V, Mo, Nb, B and Ca, and the balance being Fe and impurities, has satisfactory toughness at a high strength of 650 MPa or more by yield strength and also excellent hot workability. Therefore, it can be used as a high-strength martensitic stainless steel pipe for carbon dioxide gas corrosion resistant use, to be used in oil and/or gas well environments containing no hydrogen sulfide but carbon dioxide gas. This high-strength martensitic stainless steel pipe is an inexpensive martensitic stainless steel pipe, which does not require an addition of large quantities of expensive elements such as Ni and Mo, and moreover does not require the control of the content of P to a value less than 0.010% by mass.

Abstract: In a martensitic stainless steel tube according to the present invention, the content is determined by each of elements C, Si, Mn and Cr, and the bubble content ratio is further prescribed in accordance with the scale thickness on the outer surface of the steel tube, so that defects can be detected with high precision in the non-destructive inspection, such as ultrasonic test or the like. This allows the non-destructive inspection to be carried out with high efficiency. Moreover, there is another advantage that the weather resistance can be enhanced. The steel tube according to the present invention and the manufacturing method thereof can be suitably used in all of the technical fields in which a martensitic stainless steel tube having equal chemical composition is treated.

Abstract: In a martensitic stainless steel tube according to the present invention, the content is determined by each of elements C, Si, Mn and Cr, and the bubble content ratio is further prescribed in accordance with the scale thickness on the outer surface of the steel tube, so that defects can be detected with high precision in the non-destructive inspection, such as ultrasonic test or the like. This allows the non-destructive inspection to be carried out with high efficiency. Moreover, there is another advantage that the weather resistance can be enhanced. The steel tube according to the present invention and the manufacturing method thereof can be suitably used in all of the technical fields in which a martensitic stainless steel tube having equal chemical composition is treated.

Abstract: A martensitic stainless steel pipe, which comprises specified quantities of C, Si, Mn, P, S, Cr, Ni, Al, N, Cu, Ti, V, Mo, Nb, B and Ca, and the balance being Fe and impurities, has satisfactory toughness at a high strength of 650 MPa or more by yield strength and also excellent hot workability. Therefore, it can be used as a high-strength martensitic stainless steel pipe for carbon dioxide gas corrosion resistant use, to be used in oil and/or gas well environments containing no hydrogen sulfide but carbon dioxide gas. This high-strength martensitic stainless steel pipe is an inexpensive martensitic stainless steel pipe, which does not require an addition of large quantities of expensive elements such as Ni and Mo, and moreover does not require the control of the content of P to a value less than 0.010% by mass.

Abstract: In a martensitic stainless steel tube according to the present invention, the content is determined by each of elements C, Si, Mn and Cr, and the bubble content ratio is further prescribed in accordance with the scale thickness on the outer surface of the steel tube, so that defects can be detected with high precision in the non-destructive inspection, such as ultrasonic test or the like. This allows the non-destructive inspection to be carried out with high efficiency. Moreover, there is another advantage that the weather resistance can be enhanced. The steel tube according to the present invention and the manufacturing method thereof can be suitably used in all of the technical fields in which a martensitic stainless steel tube having equal chemical composition is treated.

Abstract: A martensitic stainless steel pipe, which comprises specified quantities of C, Si, Mn, P, S, Cr, Ni, Al, N, Cu, Ti, V, Mo, Nb, B and Ca, and the balance being Fe and impurities, has satisfactory toughness at a high strength of 650 MPa or more by yield strength and also excellent hot workability. Therefore, it can be used as a high-strength martensitic stainless steel pipe for carbon dioxide gas corrosion resistant use, to be used in oil and/or gas well environments containing no hydrogen sulfide but carbon dioxide gas. This high-strength martensitic stainless steel pipe is an inexpensive martensitic stainless steel pipe, which does not require an addition of large quantities of expensive elements such as Ni and Mo, and moreover does not require the control of the content of P to a value less than 0.010% by mass.

Abstract: The present invention provides a martensitic stainless steel seamless pipe, having no inner surface defect and suppressing a delayed fracture generation in the impact-worked portions, and a method for manufacturing such a seamless steel pipe. A martensitic stainless steel seamless pipe, characterized by consisting of C: 0.15 to 0.22%, Si: 0.1 to 1.0%, Mn: 0.10 to 1.00%, Cr: 12.00 to 14.00%, P: 0.020% or less, S: 0.010% or less, N: 0.05% or less, O (Oxygen): 0.0060% or less, at least one alloying element selected from V, Nb and Ti of 0.005 to 0.200% and B of 0.0005 to 0.0100%, and the balance Fe and impurities, satisfying either the following inequalities (1), (2), (4) and (5) or the following inequalities (1), (3), (4) and (5): C*+10N*?0.45,??(1) H1??0.003(C*+10N*)+0.0016,??(2) H2??0.0018(C*+10N*)+0.00096,??(3) Cr*?9.0,??(4) S?0.088N*+0.

Abstract: Martensitic stainless steel whose steel composition is restricted within a specific range for each element is provided. The scale layer formed on the surface of the base material consists of an inner layer scale mainly including FeCr2O4 and an outer layer scale having a thickness of not more than 20 ?m, which outer layer is deposited on the inner layer scale at a surface coverage of not less than 1% and not more than 15%. The application of rust preventive oil onto the surface of the steel ensures an excellent weather resistance during a long term, and therefore a martensitic stainless steel forming no rust either in the outdoor depository or in the indoor depository can be provided. The steel can be used to manufacture, not only steel pipes, but also steel plates, steel rods and others in a wide application field.