Hydro forming method for constructing a piece of vehicle wheel rims. The whole process will be implemented in seven stages. As the first station of raw sheet by the form Stretch a piece of cylindrical internal diameter sized the smallest inner diameter and the 1.6 height rim and this diameter is larger than the outer rim diameter. Secondly outer rim diameter cylindrical piece is the desired size trim. In the third and main stage action takes place hydro forming cylindrical piece by piece into a specific form of work (work piece) with no Punches final form and elasticity are required.

A molding apparatus for molding a metal pipe includes: a gas supply unit which supplies gas into a heated metal pipe material, thereby expanding the metal pipe material; a mold which molds the metal pipe by bringing the expanded metal pipe material into contact therewith; and a drive unit which generates a driving force for moving the mold, in which a replacement unit is replaceably provided with respect to a main body unit having at least the drive unit, and the replacement unit is configured of at least the gas supply unit and the mold.

A forming apparatus that forms a metal pipe includes: a heating unit which heats a metal pipe material; a gas supply unit which supplies gas into a heated metal pipe material, thereby expanding the metal pipe material; a die which forms the metal pipe by bringing the expanded metal pipe material into contact with the die; a cooling unit which cools the metal pipe after the forming by a cooling medium; and a control unit which controls an operation of the die, the gas supply unit, and the cooling unit, wherein the control unit makes cooling of the metal pipe by the cooling medium be performed, by controlling an operation of the die such that the die is opened and controlling the cooling unit such that the cooling unit brings the cooling medium into contact with the metal pipe, subsequently to completion of forming by the die.

A molding apparatus capable of improving the quality of a molded article is provided. A control section controls a blowing mechanism to expand and mold a metal pipe material by supplying gas into the metal pipe material held between an upper mold and a lower mold by a pipe holding mechanism. The control section controls a driving section to mold a flange portion by crushing a second molded portion of the expanded metal pipe material in a sub-cavity portion between the upper mold and the lower mold. In a molding apparatus, the control section changes movement speed of a slide during the molding of the flange portion by controlling a servomotor. Accordingly, it becomes possible to control an operation of pressing at an appropriate movement speed according to the shape or the like of the flange portion. Accordingly, it is possible to improve the quality of a molded article.

A forming device forms a metal pipe with a flange and includes a forming tool that forms the metal pipe, in which the forming tool includes a first die and a second die facing each other in a first direction in a cross-sectional view, and a third die disposed on at least one side of a metal pipe material in a second direction intersecting the first direction, and at least one of the first die and the second die is divided in the second direction and sandwiches a part of the metal pipe material in the second direction to form a flange portion.

A forming device forms a metal pipe with a flange and includes a forming tool that forms the metal pipe, in which the forming tool includes a first die and a second die facing each other in a first direction in a cross-sectional view, and a third die disposed on at least one side of a metal pipe material in a second direction intersecting the first direction, and at least one of the first die and the second die is divided in the second direction and sandwiches a part of the metal pipe material in the second direction to form a flange portion.