This invention provides an oil-well metal pipe which is capable of achieving both high yield torque and excellent galling resistance in a compatible manner. An oil-well metal pipe of the present disclosure includes a pipe main body. The pipe main body includes a pin that is formed at the first end portion, and a box that is formed at the second end portion. A plating layer is formed on a first contact surface, which is one of a pin contact surface of the pin and a box contact surface of the box, and a solid lubricant layer is formed on the plating layer. An arithmetic average roughness Ra of a second contact surface, which is the other of the pin contact surface and the box contact surface, is 0.5 to 10.0 μm, and a semi-solid or liquid anti-rust coating is formed on the second contact surface.

A head assembly system for a deionization vessel, that is convertible between a first head assembly and a second head assembly. The first head assembly includes an interchangeable head including a first threaded section; and a first insert arranged entirely within a cavity of the first threaded section. The first threaded section is threaded into a larger threaded opening of a deionization vessel. The second head assembly includes the interchangeable head; a second insert arranged partially within the cavity; and a collar threaded on the first threaded section to removably secure the second insert to the interchangeable head. The second insert includes a second threaded section arranged outside of the cavity. The second threaded section is threaded into smaller threaded opening of a deionization vessel.

A connection fitting for connecting an outlet of a high-pressure fuel pump to a high-pressure region of a fuel system of an internal combustion engine includes a first connection opening and a second connection opening. The first connection opening has a first opening axis and is configured to connect to the outlet of the high-pressure fuel pump. The second connection opening has a second opening axis and is configured to connect to the high-pressure region. The second opening axis is arranged non-coaxially to the first opening axis.

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.

Provided are methods and systems for draining underground soil moisture and water at a site. The methods and systems utilize a secured pipe system having a leading edge to drill the system into the earth, and perforations along portions of the surface of the system to receive accumulated water from underground and deliver it to the surface. A pipe cradle guide as provided is useful in the installation of the system. To also inject soil stabilizing materials (a mixture of sand and gel) into the earth using the secured pipe system, a removable canister is coupled to the distal end of the pipe system, and using water pressure the soil stabilizing materials are delivered to the soil by means of the secured pipe system.

Provided is a junction, a method for forming a junction, and a well system including a junction. The junction, in one aspect, includes a first threaded member, the first member formed of a first material, and a second threaded member threaded with the first threaded member, the second threaded member formed of a second material. In one or more aspects, the first and second threaded members define an overlapping space. In one or more other aspects, an expandable metal joint is located in at least a portion of the overlapping space, the expandable metal joint comprising a metal configured to expand in response to hydrolysis.

An extension assembly for a fire suppression spray nozzle is provided. A tube having a first end and a second end is welded to a female hose coupler at the tube's first end. A male hose coupler is welded to the second end of the tube. A support sleeve connected to the female hose coupler inserts into a fire suppression spray nozzle or another instance of the extension assembly to provide for easy alignment of the threaded connectors and for adding strength to the connection.

A quick connect coupler includes a female connector having a central bore and a plurality of recesses, and a male connector having a post insertable into the central bore. The male connector has a first tab row with a plurality of first tabs and a second tab row with a plurality of second tabs axially spaced from the plurality of first tabs. The first and second tabs are shaped corresponding to the recesses in the female connector. The first and second tab rows are circumferentially offset to effect a two- or multi-step connection between the female connector and the male connector.