Abstract: A threaded connection for pipe includes a pin and a box. The threaded connection for pipe includes a Zn—Ni alloy plated layer and a solid lubricant coating. The Zn—Ni alloy plated layer is formed on a contact surface of at least one of the pin and the box and contains 10 to 16 mass % of Ni. The solid lubricant coating is formed on the Zn—Ni alloy plated layer. The contact surface on which the Zn—Ni alloy plated layer is formed is ground. Now define arithmetic average roughness of the surface of the Zn—Ni alloy plated layer as Ra1, and arithmetic average roughness of the contact surface as Ra2. Ra1 ranges from 0.1 to 3.2 ?m. Ra1 is more than Ra2.

Abstract: This invention provides a threaded connection for oil country tubular goods that exhibits excellent corrosion resistance and galling resistance, and a method for producing the threaded connection for oil country tubular goods. The method includes a Zn—Ni alloy plating layer formation step of forming a Zn—Ni alloy plating layer, and a chromate coating formation step of forming a chromate coating after the Zn—Ni alloy plating layer formation step. The chromate coating formation step includes a chromate treatment step and a drying step. The chromate coating formation step satisfy one or more conditions selected from the following conditions 1 to 3. Condition 1: stirring speed of the chromating solution in the chromate treatment step: a linear speed of 0.5 m/s or more; Condition 2: chromate treatment time in the chromate treatment step: less than 50 seconds; and Condition 3: drying temperature in the drying step: 60° C. or less.

Abstract: An electroplating apparatus is provided that minimizes unplated regions when an alloy plating layer is provided on the surface of a thread on a steel pipe. An electroplating apparatus (10) includes an electrode (1), sealing members (2, 3), and a plating-solution supply unit (4). The electrode (1) faces the thread (Tm). The sealing member (2) is positioned within the steel pipe (P1). The sealing member (3) is attached to the end portion of the steel pipe (P1) and, together with the sealing member (2), forms a receiving space (8). The plating-solution supply unit (4) includes a plurality of nozzles (42). The nozzles (42) are positioned within the receiving space (8) and adjacent one end of the thread (Tm) and arranged around the pipe axis of the steel pipe (P1). The plating-solution supply unit (4) injects a plating solution between the thread (Tm) and electrode (1) through the nozzles (42).

Abstract: The threaded connection for pipes includes a pin, a box and a Zn—Ni alloy plating layer. The pin has a pin-side contact surface that includes a pin-side thread part. The box has a box-side contact surface that includes a box-side thread part. The Zn—Ni alloy plating layer is formed on at least one of the pin-side contact surface and the box-side contact surface. The Zn—Ni alloy plating layer is consisting of Zn, Ni, trace amount of Cr and impurities. The trace amount of Cr content of the Zn—Ni alloy plating layer is 5.0×10 counts/sec or more in terms of Cr intensity as measured by secondary ion mass spectrometry using O2+ ions as bombarding ions.

Abstract: An electroplating apparatus is provided that minimizes unplated regions when an alloy plating layer is provided on the surface of a thread on a steel pipe. An electroplating apparatus (10) includes an electrode (1), sealing members (2, 3), and a plating-solution supply unit (4). The electrode (1) faces the thread (Tm). The sealing member (2) is positioned within the steel pipe (P1). The sealing member (3) is attached to the end portion of the steel pipe (P1) and, together with the sealing member (2), forms a receiving space (8). The plating-solution supply unit (4) includes a plurality of nozzles (42). The nozzles (42) are positioned within the receiving space (8) and adjacent one end of the thread (Tm) and arranged around the pipe axis of the steel pipe (P1). The plating-solution supply unit (4) injects a plating solution between the thread (Tm) and electrode (1) through the nozzles (42).

Abstract: The threaded connection for pipes includes a pin, a box and a Zn—Ni alloy plating layer. The pin has a pin-side contact surface that includes a pin-side thread part. The box has a box-side contact surface that includes a box-side thread part. The Zn—Ni alloy plating layer is formed on at least one of the pin-side contact surface and the box-side contact surface. The Zn—Ni alloy plating layer is consisting of Zn, Ni, trace amount of Cr and impurities. The trace amount of Cr content of the Zn—Ni alloy plating layer is 5.0×10 counts/sec or more in terms of Cr intensity as measured by secondary ion mass spectrometry using O2+ ions as bombarding ions.

Abstract: An electroplating apparatus is provided that minimizes unplated regions when an alloy plating layer is provided on the surface of a thread on a steel pipe. An electroplating apparatus (10) includes an electrode (1), sealing members (2, 3), and a plating-solution supply unit (4). The electrode (1) faces the thread (Tm). The sealing member (2) is positioned within the steel pipe (P1). The sealing member (3) is attached to the end portion of the steel pipe (P1) and, together with the sealing member (2), forms a receiving space (8). The plating-solution supply unit (4) includes a plurality of nozzles (42). The nozzles (42) are positioned within the receiving space (8) and adjacent one end of the thread (Tm) and arranged around the pipe axis of the steel pipe (P1). The plating-solution supply unit (4) injects a plating solution between the thread (Tm) and electrode (1) through the nozzles (42).

Abstract: A threaded connection for pipe includes a pin and a box. The threaded connection for pipe includes a Zn—Ni alloy plated layer and a solid lubricant coating. The Zn—Ni alloy plated layer is formed on a contact surface of at least one of the pin and the box and contains 10 to 16 mass % of Ni. The solid lubricant coating is formed on the Zn—Ni alloy plated layer. The contact surface on which the Zn—Ni alloy plated layer is formed is ground. Now define arithmetic average roughness of the surface of the Zn—Ni alloy plated layer as Ra1, and arithmetic average roughness of the contact surface as Ra2. Ra1 ranges from 0.1 to 3.2 ?m. Ra1 is more than Ra2.

Abstract: There is provided a threaded connection for pipe having an excellent galling resistance and an excellent appearance. A threaded connection for pipe according to the present embodiment includes a pin (3) and a box (4). The pin (3) and the box (4) have contact surfaces (34) and (44) that include thread parts (31) and (41), metal seal parts (32) and (42), and shoulder parts (33) and (43), respectively. The threaded connection for pipe includes a Zn—Ni alloy plating layer (100) on the contact surface (34) or (44) of at least one of the pin (3) and the box (4). The Zn—Ni alloy plating layer (100) contains Cu. The Cu content of the Zn—Ni alloy plating layer (100) is 4.5% by mass or less (zero excluded).

Abstract: This invention provides a threaded connection for oil country tubular goods that exhibits excellent corrosion resistance and galling resistance, and a method for producing the threaded connection for oil country tubular goods. The method includes a Zn—Ni alloy plating layer formation step of forming a Zn—Ni alloy plating layer, and a chromate coating formation step of forming a chromate coating after the Zn—Ni alloy plating layer formation step. The chromate coating formation step includes a chromate treatment step and a drying step. The chromate coating formation step satisfy one or more conditions selected from the following conditions 1 to 3. Condition 1: stirring speed of the chromating solution in the chromate treatment step: a linear speed of 0.5 m/s or more; Condition 2: chromate treatment time in the chromate treatment step: less than 50 seconds; and Condition 3: drying temperature in the drying step: 60° C. or less.

Abstract: Provided is a plating solution for a threaded connection used for forming a plating film excellent in galling resistance, crevice corrosion resistance, and exposure corrosion resistance. The plating solution contains no cyanide, but contains copper pyrophosphate, tin pyrophosphate, zinc pyrophosphate, pyrophosphate as a metal complexing agent, and a sulfur-containing compound of 40 g/L or less (excluding 0). The sulfur-containing compound includes: a mercapto compound and a sulfide compound defined by Chemical Formula (1); a dimer formed through a disulfide bond of the mercapto compounds; and one or more types of salts thereof: RS—(CHX1)m—(CHX2)n—CHX3X4??(1), where each of m and n is an integer of 1 or 0; each of X1, X2, X3 and X4 is any one of hydrogen, OH, NH2, SO3H, and CO2H, but excluding that X1, X2, X3, and X4 are all hydrogen; and R is any one of hydrogen, a methyl group, and an ethyl group.

Abstract: An objective of the present invention is to provide a threaded connection for pipe or tube having an excellent anti-misalignment property and an appropriate shouldering torque, and further having excellent corrosion resistance and an excellent adhesiveness of a solid lubricant coating, and to provide a method of producing the threaded connection for pipe or tube. The threaded connection for pipe or tube according to the present embodiment includes a pin and a box. The pin and the box have contact surfaces including thread portions and unthreaded metal contact portions. The threaded connection for pipe or tube comprises an alloy plating layer consisting of a Zn—Ni alloy on the contact surface of at least one of the pin and the box, a phosphating layer, and a solid lubricant coating. These are stacked in an order of the alloy plating layer, phosphating layer, and the solid lubricant coating, from a contact surface side.

Abstract: In a titanium material or a titanium alloy material, in an oxide film formed on a surface of a titanium or a titanium alloy, the composition ratio of TiO (ITiO/(ITi+ITiO)×100 found from the maximum intensity of the X-ray diffraction peaks of TiO (ITiO) and the maximum intensity of the X-ray diffraction peaks of metal titanium (ITi) in X-ray diffraction measured at an incident angle to the surface of 0.3° is 0.5% or more. A titanium material or a titanium alloy material, and a fuel cell separator and a polymer electrolyte fuel cell having good contact-to-carbon electrical conductivity and good durability can be provided.

Abstract: An electroplating apparatus is provided that minimizes unplated regions when an alloy plating layer is provided on the surface of a thread on a steel pipe. An electroplating apparatus (10) includes an electrode (1), sealing members (2, 3), and a plating-solution supply unit (4). The electrode (1) faces the thread (Tm). The sealing member (2) is positioned within the steel pipe (P1). The sealing member (3) is attached to the end portion of the steel pipe (P1) and, together with the sealing member (2), forms a receiving space (8). The plating-solution supply unit (4) includes a plurality of nozzles (42). The nozzles (42) are positioned within the receiving space (8) and adjacent one end of the thread (Tm) and arranged around the pipe axis of the steel pipe (P1). The plating-solution supply unit (4) injects a plating solution between the thread (Tm) and electrode (1) through the nozzles (42).

Abstract: Provided is a metallic material including: a base metal made of a metal; a metal compound layer stacked on a surface of the base metal, the metal compound layer mainly containing a compound of at least one transition metal in the fourth period and oxygen; a platinum group portion dispersed on a surface of the metal compound layer, the platinum group portion mainly containing at least one platinum group element; and a platinum group compound coating film which covers the platinum group portion, the platinum group compound coating film mainly containing a compound of at least one platinum group element and oxygen. The at least one platinum group element contained in the platinum group portion is preferably one or more of Ru, Rh, Os, and Ir.

Abstract: An objective of the present invention is to provide a threaded connection for pipe or tube having an excellent anti-misalignment property and an appropriate shouldering torque, and further having excellent corrosion resistance and an excellent adhesiveness of a solid lubricant coating, and to provide a method of producing the threaded connection for pipe or tube. The threaded connection for pipe or tube according to the present embodiment includes a pin (13) and a box (14). The pin (13) and the box (14) have contact surfaces including thread portions (15) and (20) and unthreaded metal contact portions. The threaded connection for pipe or tube comprises an alloy plating layer (21) consisting of a Zn—Ni alloy on the contact surface of at least one of the pin (13) and the box (14), a phosphating layer (22), and a solid lubricant coating (23). These are stacked in an order of the alloy plating layer (21), phosphating layer (22), and the solid lubricant coating (23), from a contact surface side.

Abstract: The composition ratio of a titanium hydride [ITi—H/(ITi+ITi—H)]×100 found from the maximum intensity of metal titanium (ITi) and the maximum intensity of the titanium hydride (ITi—H) of the X-ray diffraction peaks measured at a surface of a titanium or a titanium alloy at an incident angle to the surface of 0.3° is 55% or more, a titanium oxide film is formed on an outermost surface of the titanium or the titanium alloy, and C is at 10 atomic % or less, N is at 1 atomic % or less, and B is at 1 atomic % or less in a position where the surface has been subjected to sputtering of 5 nm with argon. The titanium oxide film is formed by performing stabilization treatment after performing passivation treatment in prescribed aqueous solutions, and has a thickness of 3 to 10 nm.

Abstract: An electroplating apparatus applies an electroplated coating to a female thread formed on a pipe end portion of a steel pipe. The apparatus includes an inner seal member, a capsule, a discharge outlet, an opening, a cylindrical insoluble anode, a plating solution supply tube, and a plurality of nozzles. The seal member divides the interior of the steel pipe at a location longitudinally inward of a region on which the female thread is formed. The capsule is attached to the pipe end portion. The outlet is designed to discharge a plating solution inside the capsule therefrom. The opening facilitates discharge of the solution inside the capsule. The anode is disposed in the inside of the pipe end portion. The supply tube projects from an end of the anode. The nozzles eject a plating solution between the outer surface of the anode and the inner surface of the pipe end portion.

Abstract: An electro plating device includes a pipe inside seal mechanism which occludes an inner channel of a steel pipe, a tubular insoluble electrode which is disposed in a pipe end so as to be opposite to a female screw, a plating solution feed mechanism which includes a plurality of nozzles which extend radially with a pipe axis of the steel pipe as a center, and a pipe end seal mechanism which accommodates the nozzles thereinside and is mounted to the pipe end, when viewed in the pipe axial direction, a tip of each of the nozzles is positioned between the female screw and the insoluble electrode, and each of the nozzles injects the plating solution toward a direction which intersects an extension direction of the nozzle, the direction being a rotational direction of a clockwise direction or a counterclockwise direction in which the pipe axis is the center.

Abstract: Provided is a metallic material including: a base metal made of a metal; a metal compound layer stacked on a surface of the base metal, the metal compound layer mainly containing a compound of at least one transition metal in the fourth period and oxygen; a platinum group portion dispersed on a surface of the metal compound layer, the platinum group portion mainly containing at least one platinum group element; and a platinum group compound coating film which covers the platinum group portion, the platinum group compound coating film mainly containing a compound of at least one platinum group element and oxygen. The at least one platinum group element contained in the platinum group portion is preferably one or more of Ru, Rh, Os, and Ir.