A method for producing a threaded nut of a threaded drive, includes the following steps: a sleeve is produced from a steel sheet which is suitable for case-hardening; a rolling profile for a rolling contact with rolling bodies is molded on the inner circumference of the sleeve, said rolling profile being wound in a helical manner about the longitudinal axis of the sleeve; a flange is welded to the end face of the sleeve; the flange is provided with a welding surface on the flange end face facing away from the sleeve for welding to a machine part; the welding surface initially has a diffusion-inhibiting layer which inhibits the penetration of carbon; and the welding surface is exposed by removing the diffusion-inhibiting layer after case-hardening the threaded nut. A threaded nut produced according to the method can be part of a ball screw drive, the flange of which can be welded to a provided machine part by the user.

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.

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 O.sub.2.sup.+ ions as bombarding ions.

Method of manufacturing a ground apparatus and ground apparatus comprising an aluminum nut (16) having an internal thread and adapted to clamp an eyelet (28) of an electrical conductor on a corresponding contact area of the stud (12), wherein the nut (16) has at least one coating (30) which contains at least zinc, characterized in that the coating further comprises tin, in that the coating consists of an acid tin-zinc electroplating on the aluminum nut (16) and is such that the tin is between 60 and 80% by weight of the coating and the tin-zinc coating forms a layer with an average thickness of from about 5 to 16 microns

The composition according to the present disclosure is a composition for forming a lubricant coating layer on or above a threaded connection for pipes, and contains polyisobutylene, a metal soap, a wax and a basic metal salt of an aromatic organic acid. The threaded connection for pipes according to the present disclosure includes: a pin having a pin-side contact surface which includes a pin-side threaded portion; a box having a box-side contact surface which includes a box-side threaded portion; and a lubricant coating layer formed from the aforementioned composition as an outermost layer on or above at least one of the pin-side contact surface and the box-side contact surface.

The composition according to the present embodiment is a composition for forming a lubricant coating layer on a threaded connection for pipes or tubes, and contains Cr.sub.2O.sub.3, a metal soap, a wax and a basic metal salt of an aromatic organic acid. The threaded connection for pipes or tubes according to the present embodiment includes a pin and a box. The pin and the box each include a contact surface including a threaded portion. The threaded connection for pipes or tubes includes, as an outermost layer, a lubricant coating layer formed from the aforementioned composition on at least one of the contact surfaces of the pin and the box.

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 threaded tubular connection for drilling or operating hydrocarbon wells contains a portion of a tubular element with a male end having an axis of revolution and provided with a first threading extending about the axis of revolution, the male end portion being complementary with a portion of a tubular element with a female end having an axis of revolution and provided with a second threading extending about the axis of revolution, the male and female end portions being capable of being connected by makeup, each of the male and female end portions further comprising a sealing surface with a metal-metal interference, wherein the threading and the sealing surfaces of the male and female end portions are coated with a metallic anti-corrosion and anti-galling layer wherein zinc (Zn) is the major element by weight. One of the metallic anti-corrosion and anti-galling layers is coated with a passivation layer and the other is at least partially coated with a lubricant layer.

The composition according to the present embodiment is a composition for forming a lubricant coating layer on a threaded connection for pipes or tubes, and contains Cr.sub.2O.sub.3, a metal soap, a wax and a basic metal salt of an aromatic organic acid. The threaded connection for pipes or tubes according to the present embodiment includes a pin and a box. The pin and the box each include a contact surface including a threaded portion. The threaded connection for pipes or tubes includes, as an outermost layer, a lubricant coating layer formed from the aforementioned composition on at least one of the contact surfaces of the pin and the box.

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.