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.

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.

The present disclosure discloses an ultra-low pressure liquid filling forming system for a special-shaped component, including a control system, a supercharger, a driving device, a preforming unit, and a final forming unit. The present disclosure further provides an ultra-low pressure liquid filling forming method for a special-shaped component, including the following steps: S1: making an equal diameter cylindrical coil blank with an overlapping part in a longitudinal direction by using a plate blank; S2: bulging the equal diameter cylindrical coil blank into a variable diameter cylindrical prefabricated coil blank; S3: cutting and welding the overlapping part remaining on the variable diameter cylindrical prefabricated coil blank in the axial direction to obtain a variable diameter prefabricated tube blank; S4: filling liquid and press-forming the variable diameter prefabricated tube blank, so that the variable diameter prefabricated tube blank occurs compressive deformation, thereby forming the special-shaped component.

The present disclosure discloses an ultra-low pressure liquid filling forming system for a special-shaped component, including a control system, a supercharger, a driving device, a preforming unit, and a final forming unit. The present disclosure further provides an ultra-low pressure liquid filling forming method for a special-shaped component, including the following steps: S1: making an equal diameter cylindrical coil blank with an overlapping part in a longitudinal direction by using a plate blank; S2: bulging the equal diameter cylindrical coil blank into a variable diameter cylindrical prefabricated coil blank; S3: cutting and welding the overlapping part remaining on the variable diameter cylindrical prefabricated coil blank in the axial direction to obtain a variable diameter prefabricated tube blank; S4: filling liquid and press-forming the variable diameter prefabricated tube blank, so that the variable diameter prefabricated tube blank occurs compressive deformation, thereby forming the special-shaped component.

A forming apparatus which forms a metal pipe by expanding a metal pipe material, includes: a forming die for forming the metal pipe; a first electrode and a second electrode which clamp the metal pipe material at both end sides and heat the metal pipe material by causing an electric current to flow through the metal pipe material; and a first fluid supply unit and a second fluid supply unit which supply a fluid into the metal pipe material heated by the first electrode and the second electrode to expand the metal pipe material, wherein at least one of the first electrode and the second electrode is provided with a movement restriction mechanism which restricts a movement of the metal pipe material in an axial direction of the metal pipe material.

Methods for expanding a tube to create a tight fit or an interference fit with one or more fins for the manufacture of a heat exchanger are disclosed. The methods can include providing an internal pressure to the tubes in a successive pulsing manner with each pulse having a short duration. The methods can include creating a temperature differential between the bend sections of the tubes and the straight sections of the tubes such that the bend section has a lower temperature than the straight sections. The methods can include creating an external pressure differential between the bend sections of the tubes and the straight sections of the tubes such that the external pressure acting on the bend sections is greater than the external pressure acting on the straight sections.

By the control of a controller, a gas is supplied into a metal pipe material from a gas supply part so as to expand a part of the metal pipe material in sub-cavity parts, and then a driving mechanism is driven such that expanded parts of the metal pipe material are pressed by an upper die and a lower die to form flange parts. In addition, by the control of the controller, a gas is supplied into the metal pipe material after the formation of the flange parts from the gas supply part so as to form a pipe part in a main cavity part. In this manner, the controller controls the gas supply part and the driving mechanism, and thus flange parts and a pipe part having a desired shape can be easily formed.

A hot metal gas forming and quenching system and process therefor are provided. The system includes a hydraulic press, a die assembly, a rapid heating module and a rapid cooling module. The die assembly includes a progressive die which can realize the hot gas bulging and rapid cooling of the workpiece. Through the above system and the process, making pipes with uncoated plates has a lower cost than with coated and plated steel plates, with fewer structural defects and process risks. By using a progressive die, a resistance heating process, and hot gas bulging and quenching processes are performed in parallel, and the material is loaded progressively, thereby having a fast pace and a greatly improved efficiency. A heating state of parts is fully protected, oxidation is avoided, and no coating is required. After the workpiece is formed, it can be directly welded to a car body without shot blasting.

A metal pipe having an outer diameter of 150 mm to 3,000 mm and a wall thickness of 2 mm to 50 mm, and a method for manufacturing the same. The method includes a pipe-end-portion expansion step of expanding pipe end portions that are located at both ends of a mother pipe and an internal pressure application step that is performed after the pipe-end-portion expansion step and in which the mother pipe is expanded by applying an internal pressure, p, to the entire interior of the mother pipe until the internal pressure, p (MPa), that corresponds to changes in an axial compression amount s (mm), the axial compression amount, s, representing an amount of compression in a pipe axial direction against pipe extreme ends which are the both ends of the mother pipe, becomes a preset maximum internal pressure pmax (MPa), and p and s satisfy a specified formula.

A metal pipe having an outer diameter of 150 mm to 3,000 mm and a wall thickness of 2 mm to 50 mm, and a method for manufacturing the same. The method includes a pipe-end-portion expansion step of expanding pipe end portions that are located at both ends of a mother pipe and an internal pressure application step that is performed after the pipe-end-portion expansion step and in which the mother pipe is expanded by applying an internal pressure, p, to the entire interior of the mother pipe until the internal pressure, p (MPa), that corresponds to changes in an axial compression amount s (mm), the axial compression amount, s, representing an amount of compression in a pipe axial direction against pipe extreme ends which are the both ends of the mother pipe, becomes a preset maximum internal pressure pmax (MPa), and p and s satisfy a specified formula.