Provided is a method for manufacturing a cylindrical member which includes end bending of respective end portions of a plate material in a longitudinal direction, primary grooving of respective end surfaces of the plate material subjected to end bending, bending of the plate material to a ring shape, secondary grooving of respective end surfaces of the plate material subjected to bending in a ring shape, and joining of respective end surfaces of the plate material. Therefore, it is possible to manufacture a high-quality cylindrical member.

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 metal plate includes: a recessed portion provided at one end surface by cutting out the metal plate in a planar direction of the metal plate, the recessed portion having an engaging portion inside the recessed portion; and a protruding portion provided at a position on another end surface, the position corresponding to that of the recessed portion, the protruding portion protruding in the planar direction, the protruding portion being engaged with the engaging portion by applying a bending process such that the engaging portion is hooked by the protruding portion, wherein a length from a proximal end portion to a distal end portion of the protruding portion before the bending process is applied is equal to or less than a depth of the recessed portion at a position of the recessed portion, the position facing an end surface of the proximal end portion of the protruding portion.

Device (1) for calibrating and straightening hollow components, preferably welded pipes (2), the device (1) being substantially composed of a frame (5) having two side stands (6, 7), a lower cross member (8) and an upper cross member (9), a ram (10) being provided, said ram (10) being movable toward the lower cross member (8) and back by means of a pressure-operable cylinder assembly (12) supported on the upper cross member (9), and a calibrating and straightening tool (11a) being provided between the lower cross member (8) and the ram (10), wherein the calibrating and straightening tool (11a) is changeably disposed on the lower cross member (8) and on the ram (10) and can be replaced with a bending tool (11b) for bending the lateral ends (3) of sheets (4) to produce pipes (2).

A duct making apparatus includes a first station configured to accept a formable sheet material and a second station configured to receive the formable sheet material from the first station. The first station includes a mechanism for forming one of a male lock bend and a female lock seam in a leading edge of the formable sheet material. The second station includes a retractable conveyor. Movement of the sheet material from the first station to the second station defines an axis of travel of the sheet material. The retractable conveyor is selectively movable from a first position in which the retractable conveyor is in close association with the first station, and a second position in which the retractable conveyor is spaced from the first station.

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 system and method for automatically joining a cut blank has a mandrel and clamps to conform the cut blank to the mandrel. The clamps include band clamps and pad clamps that pivot about axes that are obliquely angled with respect to the centerline of the mandrel. The clamp axes on one side of the centerline are a mirror image to the clamp axes on the other side. The cut blank has a line of symmetry and is clamped to the centerline of the mandrel with a locator bar. The clamps are then moved to a clamped position. In the clamped position, one edge of the cut blank meets another edge, and a robotic welder joins the edges.

A press device includes: a first die having a shape of an elliptical cylinder; a second die having a first recess that forms a part of an elliptical-cylindrical space configured to arrange the first die therein; a third die having a second recess to be combined with the first recess to form the elliptical-cylindrical space; a first press mechanism that inserts the first die along a radial direction of the first die to the first recess of the second die over which the flat metal stock is placed so as to press the metal stock; and a second press mechanism that moves the third die relative to the first die inserted to the first recess so as to confine the first die and the metal stock in the elliptical-cylindrical space formed by the first recess and the second recess.

A sensor includes: a tubular needle member that includes a side wall and defines a hollow portion; and a linear detection member located in the hollow portion. The side wall of the needle member includes a thick portion that is thicker than another portion of the side wall in a cross-section of the needle member, and wherein the thick portion protrudes toward the hollow portion.