A forming device that expands a metal pipe material to form a metal pipe includes a die that has an upper die and a lower die, at least one of which is movable, and that form the metal pipe, an electrode that energizes the metal pipe material to heat the metal pipe material, a gas supply part that supplies a gas into the heated metal pipe material to expand the metal pipe material, and a die movement suppressing part that suppresses the movement of the die by an electromagnetic force at least when the energization to the metal pipe material is performed by the electrode.

A forming device that expands a metal pipe material to form a metal pipe includes a die that has an upper die and a lower die, at least one of which is movable, and that form the metal pipe, an electrode that energizes the metal pipe material to heat the metal pipe material, a gas supply part that supplies a gas into the heated metal pipe material to expand the metal pipe material, and a die movement suppressing part that suppresses the movement of the die by an electromagnetic force at least when the energization to the metal pipe material is performed by the electrode.

Provided is a method for producing an arm-like structure in which the arm-like structure is produced by: forming an arm precursor member having an external shape of the arm-like structure by, in a state in which a die is closed with a metal pipe member being disposed in a cavity thereof, pressurizing the pipe member with liquid supplied to an inside thereof to cause an external surface of the thus expanded pipe member to be pressed against an inner surface of the cavity; and forming a flange portion to be attached to a driven body by machining at least an end of the formed arm precursor member.

A metal pipe forming method includes: disposing a metal pipe material having a hollow shape between a pair of dies; and forming a metal pipe including a pipe portion and a flange portion by expanding the metal pipe material by supplying a fluid and bringing the metal pipe material into contact with the pair of dies. In the forming of the metal pipe, a gap which is positioned between a pair of inner surfaces of the flange portion and communicates with an internal space of the pipe portion is formed, and the flange portion is provided with a through-hole connected to the gap.

The present invention discloses a special hydraulic press for bulging pressing forming of an automobile axle housing and a pressing forming method. A hydraulic press body is a closed frame consisting of an upper cross beam, a lower cross beam, four stand columns I, II, III, and IV, four vertical pull rods I, II, III, and IV, and four transverse pull rods I, II, III, and IV, and is used for balancing a deformation force up to 3000 T in the vertical direction or the horizontal direction in the pressing forming process. During pressing forming, the downward speeds of a main hydraulic cylinder, small left and right vertical hydraulic cylinders are precisely controlled to prevent the left end, the right end and the middle of the tube blank from bending.

A forming apparatus includes: an upper die and a lower die having forming surfaces corresponding to outer surfaces of a pipe with protrusions; a moving mechanism that moves the upper die and the lower die such that a forming space for forming the pipe with protrusions is defined between the forming surfaces of the upper die and the lower die; and a gas supply unit that supplies gas to a forming material to expand the forming material. A control unit controls the movement of the upper die and the lower die by the moving mechanism and the supply of gas to the forming material by the gas supply unit such that the forming material is formed into the pipe with protrusions in the forming space.

A forming apparatus includes: an upper die and a lower die having forming surfaces corresponding to outer surfaces of a pipe with protrusions; a moving mechanism that moves the upper die and the lower die such that a forming space for forming the pipe with protrusions is defined between the forming surfaces of the upper die and the lower die; and a gas supply unit that supplies gas to a forming material to expand the forming material. A control unit controls the movement of the upper die and the lower die by the moving mechanism and the supply of gas to the forming material by the gas supply unit such that the forming material is formed into the pipe with protrusions in the forming space.

A method of forming a part includes extruding a billet through a die, forming a round, closed geometry tube from the billet, and hydroforming the round, closed geometry tube. The extrusion die contains an orifice with a central mandrel, a plurality of bridges, and a corresponding plurality of portholes between the bridges. A spacing of the bridges around the mandrel is non-equiangular. As a result, the round, closed geometry tube has non-equiangular welds after emerging from the die.

A method of forming a part includes extruding a billet through a die, forming a round, closed geometry tube from the billet, and hydroforming the round, closed geometry tube. The extrusion die contains an orifice with a central mandrel, a plurality of bridges, and a corresponding plurality of portholes between the bridges. A spacing of the bridges around the mandrel is non-equiangular. As a result, the round, closed geometry tube has non-equiangular welds after emerging from the die.

A forming device which expands a metal pipe material to form a metal pipe having a pipe portion and a flange portion includes first and second dies paired with each other and including pipe forming surfaces for forming the pipe portion and flange forming surfaces for forming the flange portion, a drive unit that drives at least one of the first and second dies, and a controller that controls the drive unit, in which, on at least one of the flange forming surfaces of the first and second dies, a protrusion portion protruding by an amount not to abut against the other flange forming surface when the dies are closed is formed and the controller controls the drive unit to form a thin wall portion at which a thickness of the flange portion becomes partially small at the flange portion by the protrusion portion pressing the flange portion.