Embodiments of the invention are directed to a male connector for establishing a line-seal for transport of fluids between pipes. The male connector is structured to increase a seating pressure of the line-seal. The male connector comprises a male portion provided at one end of the male connector. The male portion typically comprises a conical sealing frustum provided at one end of the male connector, such that the conical sealing frustum comprises convex sides. Moreover, the male connector is structured to be operatively coupled to a predetermined female connector such that the conical sealing frustum forms a substantially line-seal with the predetermined female connector for transport of a process fluid therethrough.

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.

In order to constitute a fuel high-pressure pipe that is compact and easy to connect to injectors, one of both the end sections of a fuel high-pressure pipe is formed as a first connecting section connected to a fuel supply port of one injector, and the other one of the end sections of the fuel high-pressure pipe is formed as a second connecting section connected to a fuel discharge port of another injector. The first connecting section and the second connecting section are linearly formed parallel to each other, and head sections of the first connecting section and the second connecting section, said head sections being on the connecting side to respective injectors, are formed in the directions opposite to each other.

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 method for treating a pipe, in particular a motor vehicle pipe, wherein a flare is generated at least at one pipe end of the pipe. At least areas of the flare are provided with at least one layer, which changes the friction properties of the coated surface of the flare. The flare is coated by means of plasma coating.

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.

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.