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). The direction in which plating solution is injected from the nozzles (42) is inclined at an angle larger than 20 degrees and smaller than 90 degrees toward the thread (Tm) relative to a plane perpendicular to the pipe axis.

The present invention provides a nickel-plated and thermally-treated steel sheet with excellent corrosion resistance, in which a remaining nickel amount obtained by analyzing an nickel-iron alloy layer using energy dispersive spectrometry (EDS) or electron probe X-ray microanalysis (EPMA) after pure nickel remaining on the nickel-iron alloy layer was completely removed after the heat treatment for alloying of a nickel plated layer with base iron is 0.1 wt % or more to less than 30 wt % of the total amount of iron and nickel.

An apparatus is disclosed for applying a coating to a desired object including a rotatable container having at least one container wall. An electrolyte can be retained within the container, the at least one container wall made of a material that does not allow the electrolyte to pass through the at least one container wall of the container. An anode can be positioned within the container. The apparatus can include a mount for securing the desired object such that a surface of the desired object is exposed to the electrolyte. A controller can be in electrical communication with the anode and the mount, wherein when power is supplied from the controller to the anode and the mount, particles in the electrolyte are deposited on the desired object forming a composite coating.

An electrode device is provided with a closed part facing a bottom part of a bottomed hole when inserted inside the bottomed hole, and a flow through hole linking the inside and outside of the electrode device is formed in the electrode device. When surface treatment is implemented on the inner wall surface of the bottomed hole, the hollow electrode device is inserted into the inside of the bottomed hole, the electrolytic treatment solution is made to flow through the space inside the bottomed hole, and power is applied across the electrode device and the inner wall surface of the bottomed hole. The closed part faces the bottom part of the bottomed hole as an electrode across a prescribed surface area; therefore, electroplating at the bottom part of the bottomed hole proceeds to the same extent as other sites.

An electrode device is provided with a closed part facing a bottom part of a bottomed hole when inserted inside the bottomed hole, and a flow through hole linking the inside and outside of the electrode device is formed in the electrode device. When surface treatment is implemented on the inner wall surface of the bottomed hole, the hollow electrode device is inserted into the inside of the bottomed hole, the electrolytic treatment solution is made to flow through the space inside the bottomed hole, and power is applied across the electrode device and the inner wall surface of the bottomed hole. The closed part faces the bottom part of the bottomed hole as an electrode across a prescribed surface area; therefore, electroplating at the bottom part of the bottomed hole proceeds to the same extent as other sites.

The disclosure provides for anti-scale deposition coatings for use on surface, such as on oilfield parts. The coating includes a first, sublayer of a metal, ceramic, or metal-ceramic composite, which is characterized in having a hardness in excess of 35 HRC. The coating includes a second, top layer over the first layer, that is a polymer. A surface of the first layer may be conditioned to have a roughened or patterned topology for receipt of and adherence with the at least one top layer. The first layer may provide the coating with hardness, and the at least one top layer may provide the coating with low-friction and anti-scale properties.

The threaded connection for pipes includes a pin, a box and a ZnNi 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 ZnNi alloy plating layer is formed on at least one of the pin-side contact surface and the box-side contact surface. The ZnNi alloy plating layer is consisting of Zn, Ni, trace amount of Cr and impurities. The trace amount of Cr content of the ZnNi alloy plating layer is 5.010 counts/sec or more in terms of Cr intensity as measured by secondary ion mass spectrometry using O.sub.2.sup.+ ions as bombarding ions.

The threaded connection for pipes includes a pin, a box and a ZnNi 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 ZnNi alloy plating layer is formed on at least one of the pin-side contact surface and the box-side contact surface. The ZnNi alloy plating layer is consisting of Zn, Ni, trace amount of Cr and impurities. The trace amount of Cr content of the ZnNi alloy plating layer is 5.010 counts/sec or more in terms of Cr intensity as measured by secondary ion mass spectrometry using O.sub.2.sup.+ ions as bombarding ions.

A guide system for use in electro-processing a bore of a gun barrel includes a non-conductive external bore guide and a non-conductive internal bore guide. The external bore guide is an adapter that is configured to removably engage the outside of the gun barrel and includes a conduit formed therein. The conduit is disposed such that it is axially aligned with a bore of the gun barrel when the external bore guide is engaged with the gun barrel. The internal bore guide is elongated and includes an axial recess that is sized to seat an electro-processing electrode (an anode). A method for uniformly plating the bore includes moving an anode through the gun barrel at one or more rate(s) of travel to uniformly plate the bore is also disclosed. The plating is sufficiently uniform to conform to military specifications. The systems, methods, support structures, etc. described herein are particularly well-suited to plating small-bore gun barrels.

Embodiments of the present technology may include a tubular product for oilfield applications. The tubular product may include a tubular substrate, which may include a ferrous alloy. The tubular substrate may have an inner surface characterized by an inner diameter and an outer surface characterized by an outer diameter. The tubular product may also include a first layer deposited over at least one of the inner surface or the outer surface. The first layer may include aluminum. The tubular product may further include a second layer, which may include aluminum oxide formed by micro arc oxidation of a portion of the first layer.