A tube fitting is provided with a resin coating layer over a coated region surfaces of a threaded portion and a contact portion. The resin coating layer includes a polyethylene based substance, a lubricant, and solid particles. When mass per unit area w (g/m.sup.2) is defined as a value obtained by dividing the mass difference between a state with the resin coating layer and a state without the resin coating layer by the surface area of the coated region, the mass per unit area w satisfies a relation 0.79<w<10.07.

An axial force measurement device includes a frame, a tightening actuation unit that performs tightening operation upon a screw type tube fitting installed upon a tube upon which is formed an annular portion projecting in the radially outward direction from the tube, a testing member, and a mating member holding unit that holds the testing member into which the tube fitting is screwed and that is coupled to the tube. The tightening actuation unit and the mating member holding unit are provided to the frame in line along the direction of a reference axis that extends in the direction of the center line of the tube fitting and the tube axis of the tube. The testing member has a first part that engages with the tube fitting, and a second part against which the annular portion of the tube is pressed.

A method for manufacturing a tube fitting includes steps of: preparing the tube fitting; and forming a resin coating layer upon a coated region provided upon the surface of the tube fitting. Forming the resin coating layer includes: dipping the tube fitting into a coating material that includes as components a polyethylene based substance, a lubricant, and solid particles and having viscosity within a range of 4.24 to 5.27 mPa.Math.s at 25? C., and adhering the coating material to the coated region; and, drying the coating material which is adhered to the coated region of the tube fitting. In the dipping step, the mass per unit area w is controlled within a range 0.79<w<10.07 by dipping the tube fitting while regulating a temperature of the coating material within a range of 30? C. to 40? C.

A flare-type brake line assembly includes (a) a brake tube having a flare with a first sealing surface, (b) a brake component having a port with a second sealing surface and (c) a tube nut to secure the brake tube and brake component together. At least one of the two sealing surfaces is treated to increase the coefficient of friction between those surfaces. A related method is also disclosed.

Fluidic connection assemblies, ports, unions and other components are provided that are well-suited for use in HPLC and UHPLC, as well as in other analytical instrument systems. Such assemblies, ports, unions and components can be biocompatible.

Provided is a steel fuel conveying pipe with high quality which has high resistance to corrosive fuel and followability, and allows working after plating. The steel fuel conveying pipe is characterized in that a Ni-plate layer is formed on an inner surface of a steel pipe of base material, the Ni-plated layer is wholly composed of a mutual diffusion layer including the base material and Ni and a non-mutual diffusion layer including only Ni formed on an outermost surface of the diffusion layer, a layer thickness of the non-mutual diffusion layer is 3 m or more, and a total layer thickness of the mutual diffusion layer and the non-mutual diffusion layer is 10 m or more and 25 m or less.

A fastener for connecting a coated conduit to a fitting or to another coated conduit includes a bushing and polymeric material coating and surrounding an external surface of the bushing. The bushing includes internal and external threading The polymeric material includes a central portion coating at least the first end of the bushing, a first flexible sleeve extending from the central portion in a first direction and creating a cavity, and a second flexible sleeve extending from the central portion in a second direction, opposite the first direction. The external threading of the bushing is configured to be threaded into a fitting or conduit such that the first flexible sleeve fits over a circumference of the fitting or a coated conduit, and the internal threading of the bushing is configured to be threaded onto coated conduit such that the second flexible sleeve fits over a circumference of the coated conduit.

The invention relates to a screw element for the connection of tubes, preferably motor vehicle lines. A threading and at least one contact surface without threading are provided on the screw element. The screw element has an outer coating and an inner coating. The outer coating comprises a first polymer and nanoparticles of a first solid material. The inner coating may also comprise nonoparticles or a polymer.

A connection assembly comprising a motor vehicle fluid line and a connection fitting, wherein the motor vehicle fluid line includes an inner tube made of aluminum. The connection fitting is in contact with the inner tube. At least the surface of the connection fitting is made of aluminum, at least in the region of the contact surface between the connection fitting and the inner tube.

A tube nut and a brake tube assembly are provided. A pipe is disposed within the bore of the nut. A first coating is disposed on an outer surface of the nut. The first coating has a corrosive resistance greater than the bore so as to promote corrosion within the bore. The corrosion forms a seal which is pinched between the bore and the pipe. The tube nut and brake tube assembly may include a second coating disposed on the bore. The first coating has a corrosive resistance greater than the second coating so as to promote corrosion within the bore.