An expansion dowel is provided, which includes at least one dowel body and a bolt, the bolt including an expansion body, which forces the dowel body radially to the outside when the expansion body is displaced in an extraction direction relative to the dowel body, a corrosion protection layer and an antifriction layer covering the corrosion protection layer being provided on the expansion body. It is also provided that the corrosion protection layer is a Zn/Ni coating or a Zn/Fe coating. A manufacturing method for an expansion dowel of this type is also provided.

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 metallic terminal includes a terminal body, a first plating layer, a second plating layer, and a third plating layer. The first plating layer is on the terminal body, and the thickness of the first plating layer at the bent portion of the terminal body is 0.3 to 1.75 micrometers, and the thickness of rest portions of the first plating layer is 2 to 10 micrometers. The second plating layer is on the first plating layer and corresponds to the contact portion of the terminal body, and the thickness of the second plating layer is 0.5 to 2 micrometers. The third plating layer is on the first plating layer and corresponds to the soldering portion of the terminal body, and the thickness of the third plating layer is 0.01 to 0.1 micrometers. A manufacturing method of metallic terminal is also provided.

A pin for a coupler assembly for rotatably coupling a beam of a circle assembly of a grader machine with a bracket of a moldboard assembly of the grader machine includes a body defining a head portion and a shank portion. The shank portion integrally extends from the head portion. The head portion is adapted to be seated over one or more of the beam and the bracket. The shank portion is adapted to pass through the beam and the bracket to rotatably couple the beam and the bracket about the shank portion. A grease gallery is defined through the head portion, extending into the shank portion. The body defines multiple grease passages branching out from the grease gallery up to corresponding sections of an outer surface of the shank portion where the beam and the bracket are correspondingly adapted to lie in rotatable registration with the shank portion.

A threaded connection for pipe includes a pin and a box. The threaded connection for pipe includes a ZnNi alloy plated layer and a solid lubricant coating. The ZnNi 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 ZnNi alloy plated layer. The contact surface on which the ZnNi alloy plated layer is formed is ground. Now define arithmetic average roughness of the surface of the ZnNi 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.

A metallic fastener has a threaded portion coated with a composition. The composition includes (a) a paraffin wax with a melting temperature in the range of 50 to 70 C. (b) 1 to 5 parts by weight (pbw) of a resin per pbw of paraffin wax, (c) 0.1 to 0.25 pbw graphite per pbw of paraffin wax, and (d) 0.05 to 0.30 pbw of an FDA-approved silica per pbw of paraffin wax. A process for coating the metallic fastener includes: (i) providing the composition as defined above, (ii) maintaining the fastener or bringing it to a temperature in the range of 30 to 70 C., (iii) applying the composition at a temperature in the range of 100 to 170 C., (iv) optionally, removing surplus composition, (v) cooling the fastener to less than 100 C., (vi) finishing the fastener in a water bath, and (vii) drying the fastener.

Disclosed is a method for the production of electroplated components. In the disclosed method, an edge layer of a component to be coated is subjected to a mechanical treatment in which the edge layer is deformed at least in portions, consequently the structure of the edge layer being modified at least in portions and hydrogen traps being produced in the modified portions of the edge layer.

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 ZnNi alloy plating layer formation step of forming a ZnNi alloy plating layer, and a chromate coating formation step of forming a chromate coating after the ZnNi 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.

A threaded connection for pipes includes a pin, a box, a shoulder part plating layer, and a non-shoulder part plating layer. The shoulder part plating layer has an outermost layer formed of a high friction coefficient plating layer, and is arranged on a pin side shoulder part and/or a box side shoulder part. The non-shoulder part plating layer has an outermost layer formed of a low friction coefficient plating layer having a coefficient of friction lower than a coefficient of friction of the high friction coefficient plating layer, and the non-shoulder part plating layer is arranged on at least one of a pin side thread part, a pin side metal seal part, a box side thread part, and a box side metal seal part.

The present invention has an objective to provide a threaded connection for pipe or tube including a pin and a box, having excellent galling resistance, torque property, and anticorrosion property, and still having an excellent adhesiveness with a lubricating coating even when being repeatedly exposed to high temperature and very low temperature, and to provide a method for 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 a thread portions and and unthreaded metal contact portions, respectively. The threaded connection for pipe or tube comprises an electroplating layer consisting of a ZnNi alloy, a mechanical plating layer consisting of Zn or a Zn alloy, and a lubricating coating, on the contact surface of at least one of the pin and the box, in this order from a contact surface side.