A method for manufacturing a pipe includes: press-forming a plate member into a U shape; and press-forming the plate member formed into the U shape into an O shape. The pipe includes a pipe body and a tapered part tilted radially inward and protruding from one end of the pipe body. Before the plate member is press-formed into the U shape, a boundary between a portion of the plate member corresponding to the pipe body and a portion of the plate member corresponding to the tapered part is pressed from a surface of the plate member corresponding to an inner peripheral surface of the pipe to bend the portion of the plate member corresponding to the tapered part toward the surface of the plate member corresponding to the inner peripheral surface of the pipe.

A shaft assembly comprises a hollow shaft and at least one working component disposed therein. A method of forming the shaft assembly includes a step of providing at least one generally planar preform. The preform is then formed into a “U”-shaped partial cylinder. One or more working components may then be assembled and connected to an interior of the partial cylinder. The partial cylinder is then further formed into a hollow cylinder having a generally circular cross-sectional shape, thus surrounding the one or more working components to secure a position thereof in an interior of the hollow cylinder. The hollow cylinder may then be held stationary and a welding operation performed thereon to form the hollow shaft. Once the hollow shaft is welded, post process machining may then be performed thereon as desired to further finish the hollow shaft.

A needle member includes: a tubular side wall through which a hollow portion extends in a longitudinal direction. An opening portion connected to the hollow portion extends laterally through the tubular side wall. The tubular side wall comprises a side wall reinforcement portion located at a position opposing the opening portion, wherein the hollow portion is interposed between the opening portion and the side wall reinforcement portion.

A method of manufacturing a filter pipe for vehicles which has an expanded tube portion with a different diameter at one side and is provided with a plurality of through holes formed along a circumferential direction includes: forming the plurality of through holes in a mother member; forming furrows at one end portion of the mother member; forming a planar member having the plurality of through holes and the furrows by a shearing process of the mother member; bending the planar member in a tubular shape and spreading the furrows to form an area where the furrows are formed in an expanded tube shape; and adhering both facing end portions of the planar member so as to form a body having the expanded tube portion at one side thereof.

A method of production of a shaped article able to suppress occurrence of shaping defects, that is, a method of production of a shaped article including a first step of press-forming a metal plate (1a) into a U-shape to obtain a U-shaped article (1b) having a bottom part (2) straight extending in a longitudinal direction and a second step of press-forming the U-shaped article (1b) to bend it in the longitudinal direction so that the bottom part (2) of the part projects to the inside and obtain a U-cross-section bent article (1c).

A method for manufacturing a ring includes clamping a first region of a metal sheet against a mandrel, and, while the first region of the metal sheet is clamped against the mandrel, bending the metal sheet around the mandrel to join opposite end faces of the metal sheet and form the ring shaped to the mandrel. A system for manufacturing a ring from a metal sheet includes (a) a mandrel having a ring-shaped surface, (b) a clamp facing the ring-shaped surface and configured to clamp a first region of a metal sheet to the mandrel, and (c) a plurality of dies configured to bend the metal sheet around the mandrel, while the clamp clamps the first region to the mandrel, to join opposite end faces of the metal sheet and form a ring shaped to the ring-shaped surface.

A pipe is formed by press molding a U-shaped member including a U-shaped cross section. The U-shaped cross section includes at least five curved portions. The curved portions include a center curved portion facing an opening of the U-shaped cross section defined by both edges of the U-shaped cross section; a first right curved portion; a second right curved portion; a first left curved portion; and a second left curved portion. At least the center curved portion, the first right curved portion, and the first left curved portion each have a radius of curvature smaller than a radius of curvature of a corresponding portion of the pipe cross section.

A manufacturing method of a member according to an aspect of the present invention is a manufacturing method of a member including a specific three-dimensional tubular portion, the manufacturing method including: a U-forming step of performing U-forming on metal material sheet using a U-forming die and punch including a U-forming punch to manufacture a U-formed article having a recessed cross-sectional shape; and an O-forming step of causing side end portions of the U-formed article to abut each other by an O-forming die to form abutting portions, in which a forming condition ratio a=Du/Do is set to 0.85 to 0.95.

A heat transfer tube and a heat exchanger incorporating at least one heat transfer tubes are provided. The heat transfer tube and the heat exchanger are configured to operate in both a heating mode and a cooling mode (e.g., to optimize the reversible function a heat pump). The heat transfer tube includes a tube body with an interior surface and an exterior surface. The tube body defining an outer diameter (D.sub.o) and a wall thickness (W.sub.T), wherein a ratio (W.sub.T/D.sub.o) the wall thickness (W.sub.T) to the outer diameter (D.sub.o) is between 0.061 and 0.071. The heat transfer tube includes a plurality of adjacent helical fins protruding circumferentially around the interior surface of the tube body, and at least one groove disposed between the plurality of adjacent helical fins. The configuration of the heat transfer tube(s) is optimal for the reversible function of the heat pump.

An apparatus (10) for joining a predetermined geometrical profile shape from a sheet material (SM) includes a positioning assembly (12) including a base member (14) and a frame (16) that is operable to receive the sheet material (SM), to configure the sheet material in a predetermined orientation and to linearly translate the sheet material along a process direction (20). A Z-bar (22) is configured to guide a first longitudinal edge (FE) and second longitudinal edge (SE) of the sheet material (SM) into adjacent alignment along the process direction (20). A welding and forging assembly (60) welds and then forges a seam between the first longitudinal edge (FE) and the second longitudinal edge (SE) of the associated sheet material (SM).