Abstract: Apparatus and associated methods for actuating variable stiffness material (VSM) structures and achieving deformation of the structures. The apparatus and the associated methods use internal embedded actuation elements and/or externally attached elements to the VSM structures to achieve the desired deformation. In particular, the actuation can be changed due to the variable stiffness nature of the materials. That is, the invention provides the ability to control the deformation of structures using local stiffness control over subregions of the component in addition to or in substitution for actuation. Furthermore, the invention exploits the variable stiffness properties of the VSM structures to enable new functionalities impossible to realize with conventional constant stiffness materials.

Abstract: A pressure relief bursting disc has a flange portion, a sloping portion interior of the flange portion and a dished portion interior of the sloping portion. The sloping portion has its wider end joined to the flange portion and slopes up from the flange portion in a first direction and is joined at its narrower end directly to the dished portion. The dished portion has its concave side facing in the first direction. In use pressure is applied to the concave side of the dished portion. The disc has a line of weakness, in the sloping portion. This shape achieves reliability of the burst strength, because the sloping portion buckles at the burst strength.

Abstract: A system for hydroforming a workpiece containing fluid at elevated pressure includes a die in which the workpiece is formed, a source of control pressure, a tank at low pressure, and a valve that includes a displaceable control element that alternately moves between an open state and a closed state, opening and closing, respectively, a passage that hydraulically connects the fluid in the workpiece and the tank in response to the relative magnitudes of a first force applied to the control element by the control pressure source and a second force applied to the control element by pressure of the fluid in the workpiece acting on the control element in opposition to the first force.

Abstract: A superplastic forming apparatus and method for forming a sheet of material at an elevated temperatures into a workpiece having a complex geometry. The process takes advantage of a mechanical forming step, which draws material along a major axis to form a first preform. Upon completion of the first mechanical forming step, a second, initial superplastic forming step acts on the first preform to create a second preform having a plurality of channels or grooves located thereon. The grooves or channels function to draw additional material prior to the second or final gas forming step, which completes the forming process by driving the material against a forming surface. Accordingly, the method and apparatus function to reduce forming time and eliminate thinning and wrinkling of the sheet material during the forming process.

Abstract: A quick plastic forming (QPF) tool is provided in which a thermal gap is created that reduces or eliminates some of the conductive heat loss paths when the QPF tool is in an open position during part removal or sheet loading. By reducing conductive heat loss, a more precise temperature control for the QPF tool from manufacturing cycle to manufacturing cycle may be realized. The QPF tool may also have a thermal gap when the tool is placed in a semi-open position during idle times. The QPF tool may also include components for creating the thermal gap when the QPF tool is moved to the open position and control the lateral movement of the part forming section of the QPF tool as the part is moved between the open position and the closed position.

Abstract: An apparatus comprising a platform, a stylus, and an ultrasonic energy generation system. The platform may be capable of holding a sheet of material. The stylus may be capable of impinging the sheet of material to incrementally form a shape for a part. The ultrasonic energy generation system may be capable of sending ultrasonic energy into at least a portion of the sheet of material in a location on the sheet of material where the stylus impinges the sheet of material.

Abstract: A method of electrohydraulically trimming a blank involving positioning a blank on a trimming member having a cutting edge such that a portion to be trimmed extends over the cutting edge and is in fluid communication with a chamber. Immobilize the blank with respect to the trimming member. Position a pair of electrodes in the chamber proximate the portion of the blank to be trimmed such that the electrodes and the trimming member are on opposite sides of the blank. Electrically connect the electrodes to a capacitor. Charge the capacitor. Fill the chamber with fluid to submerge the electrodes and to contact the portion of the blank to be trimmed. Discharge the capacitor across the electrodes to generate a pressure pulse that pushes the portion of the blank to be trimmed against the cutting edge thus trimming it off the blank.

Abstract: The subject matter of the present invention is a method of shaping a metallic hollow member in a shaping tool (1, 20, 50) at increased temperature and under internal pressure, said hollow member (5) protruding at one end at least from said shaping tool (1), the configuration of the tool mold and/or the shaping parameters acting onto said hollow member being selected in such a manner that said hollow member (5, 59) substantially keeps its original shape outside said tool (1, 20, 50), with said tool being heated in the region of the cavity and a tool, said tool being completely made from a homogeneous ceramic material with the component part being heated inductively, the cavity having a tribological additional coating in order to minimize friction of the component part against the wall and/or the affinity of the component part with the material of the cavity wall.

Abstract: A process for forming a large-surface metal plate into a shaped part includes using a molding tool. The tool includes a reservoir filled with incompressible fluid work medium, clamping jaws and a shaping die movable towards the reservoir. Profiling elements, corresponding to each other, are configured in the interior of the reservoir and on the outer edge of the shaping die. The external high pressure punching by means of the shaping die moved forward against the high pressure of the fluid work medium is ended, when the shaping die has reached the profiling elements in the reservoir, by the pressure of the fluid work medium in the reservoir being reduced. The boundary sections of the metal plate are then formed between the profiling elements, pressed against each other, of the shaping die and the reservoir, at low pressure of the fluid work medium or at zero pressure.

Abstract: A method for shaping a conical metal tube using a tool that has sealing pistons and a die cavity with a complex contour is described. The die cavity has two ends with a cylindrical portion of the die cavity located at each end. The method includes inserting the conical tube into the die cavity such that the ends of the conical tube protrude into the cylindrical sections of the die cavity. Sealing pistons engage the tube ends and press each tube end against a cylindrical portion of the die cavity to seal an interior space of the conical tube. The tube is shaped by applying pressure to the sealed interior of the tube to force the tube against the complex contour of the die cavity while simultaneously axially compressed the tube by exerting axial forces on the tube ends with the sealing pistons.

Abstract: The invention relates to a method for producing a can body (2) which is characterized in that a film piece (3c) is cut from a film web (3b), said film piece (3c) is wound up on a winding spindle (7) from its front edge to its rear edge and is maintained on the winding spindle (7) so that it somewhat overlaps. The film piece (3c) is transferred from the winding spindle (7) to a concave inner surface (11a) and the film areas of the front edge and the rear edge resting against each other are sealed with each other on the concave inner surface (11a) in the area of overlapping (14). According to the invention, a closed film piece (3d) can be transferred without complication onto a can body (2), thereby conferring on the can body (2) the function of the stable structure and on the film piece (3d) the function of the décor or the inner barrier in such a manner that both functions can be optimized in a substantially independent manner.

Abstract: A method for forming a high tensile strength metal sheet (HTSMS), which is performed in a power press machine composed of a die, a punch and a blank holder, is disclosed. The HTSMS is placed between the die and punch with blank holder. A step portion appears at both an outer side of the punch and a pressing portion of the blank holder. The step portion is corresponding to a predetermined bent portion of the HTSMS. A step will be formed at an edge of the HTSMS by progressively pressing of the step portion to avoid recoil of the HTSMS after forming process.

Abstract: A variable thickness sputtering target which increases the target material thickness at strategic locations to greatly improve the yield of usable wafers per target, and a method of manufacturing such target comprising forming a generally flat and circularly shaped target blank so that a thickness dimension between the top and bottom surfaces decreases as a function of radius of the target blank. The variable thickness target blank is then formed into a variable thickness dome shaped target member having a bottom portion and a sidewall portion, wherein a wall thickness of said variable thickness dome-shaped target member is thickest proximate a center portion of said bottom portion. In one embodiment of the invention, the variable thickness target blank is formed by clock rolling (or compression rolling) the target blank with crowned rolls to obtain a variable thickness target blank.

Abstract: Magnesium and other metal alloy sheet materials are deformed at hot forming temperatures into vehicle body panels and other articles. Many such hot forming operations are improved in speed and product quality by predetermining a static recrystallization temperature of the sheet material. As the sheet material is being heated to its hot forming temperature, deformation is commenced below the static recrystallization temperature. As heating and deformation are continued, dynamic recrystallization of the workpiece occurs and deformation may proceed faster and to a greater extent.

Abstract: A ferrous metal tool is provided for the forming of light metal sheet workpieces at elevated temperatures, with the forming surface of the tool prepared to minimize friction and adhesion when engaged in deformation of the hot sheet metal. The forming surface of a steel tool is nitrocarburized to form a compound layer and diffusion layer on the surface. The compound layer initially comprises an outer gamma-phase material and an underlying epsilon phase material. Gamma-phase material is removed to expose underlying epsilon phase material, and low friction particles are embedded in the modified nitrocarburized compound layer of the forming tool.

Abstract: The present invention provides a method and apparatus for forming a ductile sheet or work piece into a part or component. The method includes using a forming apparatus wherein the workpiece is placed between and upper die and a blank holder and then lowered onto a punch such that continued lowering of the upper die draws the workpiece around the punch. Once the draw process is complete, gas pressure acts on one side of the workpiece to press the workpiece against a forming surface of the punch to complete the forming process.

Abstract: Magnesium and other metal alloy sheet materials are deformed at hot forming temperatures into vehicle body panels and other articles. Many such hot forming operations are improved in speed and product quality by predetermining a static recrystallization temperature of the sheet material. As the sheet material is being heated to its hot forming temperature, deformation is commenced below the static recrystallization temperature. As heating and deformation are continued, dynamic recrystallization of the workpiece occurs and deformation may proceed faster and to a greater extent.

Abstract: A hydro forming apparatus comprises a lower base; a lower mold mounted on the lower base and provided with an U-shaped lower cavity; an upper mold provided with a U-shaped upper cavity corresponding to the lower cavity and configured to be coupled with the lower mold; an upper base mounted on the upper mold and configured to be coupled with the lower base; and an adjusting unit for adjusting the shape of the U-shaped lower and upper cavities.

Abstract: The present invention provides a method and apparatus for forming a ductile sheet or work piece into a part or component. The method includes using a forming apparatus wherein the workpiece is placed between and upper die and a blank holder and then lowered onto a punch such that continued lowering of the upper die draws the workpiece around the punch. Once the draw process is complete, gas pressure acts on one side of the workpiece to press the workpiece against a forming surface of the punch to complete the forming process.

Abstract: The present invention relates to a heating and forming apparatus for sheet material and method for rapid heating and shaping of sheet material. The apparatus comprises a first and second respectively movable forming dies, with the first forming die having a forming surface and defining a cavity with the second forming die. The apparatus is adaptable to receive a sheet material positionable within the cavity. A heating mechanism is placed within the cavity to heat the sheet material. The forming surface of the first forming die is not substantially heated. A pressurization mechanism is in communication with the cavity to move the sheet material into conformity with the forming surface of the first die. An improvement in the process of stretch forming a sheet material into a product by using quick plastic forming (QPF) or superplastic forming (SPF) is provided.

Abstract: A press-forming device has a punch (2), a die (7) which relatively moves with respect to the punch (2), a strain amount measuring means (8) which is provided inside a member to be controlled and measures a strain amount of the aforesaid member to be controlled which occurs in accordance with press-forming, when at least one of the punch (2) and the die (7) is made the aforesaid member to be controlled, and a strain amount control means (9) which is provided in the aforesaid member to be controlled and controls the strain amount of the aforesaid member to be controlled which occurs in accordance with press-forming. The strain amount control means (9) controls a drive amount of the aforesaid member to be controlled so that the strain amount measured by the strain amount measuring means (8) is in a predetermined range during forming. Thereby, reduction in a surface strain, improvement in shape fixability or the like of a press formed product can be achieved.

Abstract: A method for shaping partially enclosed structures such as pipes, the method comprising: filling the structure with ERF, applying an electrical field to the ERF to increase its viscosity, shaping the structure, removing the field and removing the ERF from the structure.

Abstract: The invention concerns a method for the creation of addendums (4) of tools for sheet metal formed parts (2). In the case of this method, fill surfaces (7) for the smoothing of irregular zones of a component edge (3) are generated. Initial directions (31) of sectional profiles (10) are determined in such a manner, that sectional profiles (10) at a distance from one another are arranged along a component (3, 8) with utilization of these initial directions (31) and that an addendum (4) is creatable by the connection of these sectional profiles (10).

Abstract: A method for manufacturing a bursting disk from a sheet or foil is disclosed. The bursting disk has an edge for clamping the bursting disk in a clamping device and a middle region enclosed by the edge, with the following manufacturing steps: the sheet or foil is clamped with a first portion forming the future edge of the bursting disk, said first portion defining a second portion which corresponds to the future middle region of the bursting disk. A third region is defined, which is located within the second portion of the sheet or foil, a part of the second portion enclosing the third portion of the sheet or foil is clamped completely by means of a pair of clamping jaws or female dies, the sheet or foil is deformed for a first time in the third portion, the third portion being located within the second portion, which remains undeformed.

Abstract: In primary press forming process, a piece of blank sheet metal is draw worked so as to form a preformed work piece (Wb) provided with a bent portion (a) substantially conforming to a three dimensional contour of a leading edge of a blade to be protected and extending along a longitudinal direction, and a pair of planar portions (b and c) extending from either side of the bent portion. In a secondary press forming process, the planar portions (b and c) of the preformed work piece are stretch formed into a final shape that conforms to the corresponding profile of the blade while the bent portion (a) of the preformed work piece is clamped and protected from deformation.

Abstract: The method according to the invention for working in pressing dies using marking paint wherein a fluorescent marking paint is used. This enables the operator in the manual working in of pressing dies to identify the painted tool surface without error and error-free detection of the tool surface occupied by marking paint is also possible by means of suitable devices (camera) for working-in of the pressing die which is done more or less automated.

Abstract: Disclosed is a piercing device of a hydroforming mold with a lower steel having a cavity therein, which can make the replacement of the pierce punch easier. The piercing device comprises: a pierce punch, the front edge portion of which is inserted into the cavity, for punching a hole through a molding material; a pierce cylinder for providing hydraulic pressure; a rod connected to the pierce cylinder, which is to be operated by the hydraulic pressure; and a pierce block connecting the rod and the pierce punch, wherein the length between the front edge portion of the rod and the pierce punch is greater than the length of the pierce punch.

Abstract: A profile mother pipe for hydraulic bulging of the present invention has a peripheral length whose outer diameter is gradually increased or decreased from one end to the other end in an axial direction. In the profile mother pipe, a holding portion whose peripheral length is increased toward a pipe end face on one end side can be formed on at least one end side and a parallel portion can be formed on the other end side where the holding portion is not formed. In a working apparatus and method in which the profile mother pipe is used, pressing working can be performed from the pipe end toward the axial direction, even in use of the profile mother pipe whose sectional shape is largely varied in the axial direction. Therefore, an expansion ratio larger than ever before can be obtained in a hydraulic bulged product to which hydraulic bulging is performed.

Abstract: A method and apparatus for forming a sheet of ductile material by superplastic forming is disclosed. The method is directed to first creating a pre-form by mechanical forming in which the pre-form is created with a die and punch. Thereafter the pre-form is subjected to gas pressure in a forming cavity to complete formation of the part. A metallic gasket is provided to ensure that no pressurized gas escapes from the forming cavity.

Abstract: A pressing method by which through holes are formed using a punch in a target plate material having a first face and an opposite second face. When the target plate material is punched with the punch from the second face in such an orientation that the first face of the target plate material is in contact with an elastic base, depressed portions are formed. The depressed portions are curved toward a direction in which the through holes are punched to sink downward in the form of funnel as they approach peripheries of the through holes, and are located at peripheral portions around the through holes that are formed in the target plate material in such a manner that the peripheral portions are pushed in toward a deeper side in a thickness direction of the base against an elastic force of the base and are deformed.

Abstract: The invention relates to a vacuum-assisted method and a device for forming an essentially flat blank (12) of metal into a thin-walled, shell-type body (14), especially for performing the method in accordance with one of the preceding claims, that has a supporting structure (16) forming a mold chamber (18) that holds the blank (12) during increasing deformation into the thin-walled, shell-body (14), a device (20) allocated to the supporting structure (16) for clamping the blank (12) about its circumference (22) to the supporting structure (16), that seals the reverse face (24) of the blank (12) facing towards the mold chamber (18) against the front face (26) of the blank (12) facing away from the mold chamber (18), and a device (28) allocated to the mold chamber (18) that also communicates with the mold chamber (18) for applying a vacuum and evacuating the mold chamber (18), and at least one forming tool (50) applied to the front face (26) of the blank (12) is/are allocated to the supporting structure (16), an

Abstract: A hydroforming device includes a top die and a bottom die, set between which is a metal element to be formed and which are pressed against one another during a hydroforming process. A relative movement of the two dies between the open condition and the closed condition is controlled by a hydraulic cylinder. The opening of the two dies during the hydroforming process, when the forming cavity is filled with liquid at a high pressure, is prevented by applying on the two dies a force generated by means of two wedge-shaped members, which are horizontally mobile, controlled by respective actuator means and having inclined surfaces in contact with corresponding inclined surfaces of a vertically mobile member. The mobile member and the hydraulic cylinder are set operatively in series between one and the same die of the two dies and the base of the hydroforming cell.

Abstract: A method and apparatus for forming a sheet of ductile material by superplastic forming is disclosed. The method is directed to first creating a pre-form by mechanical forming in which the pre-form is created with a die and punch. Thereafter the pre-form is subjected to gas pressure in a forming cavity to complete formation of the part. A metallic gasket is provided to ensure that no pressurized gas escapes from the forming cavity.

Abstract: A process for forming a large-surface metal plate into a shaped part includes using a moulding tool. The tool includes a reservoir filled with incompressible fluid work medium, clamping jaws and a shaping die movable towards the reservoir. Profiling elements, corresponding to each other, are configured in the interior of the reservoir and on the outer edge of the shaping die. The external high pressure punching by means of the shaping die moved forward against the high pressure of the fluid work medium is ended, when the shaping die has reached the profiling elements in the reservoir, by the pressure of the fluid work medium in the reservoir being reduced. The boundary sections of the metal plate are then formed between the profiling elements, pressed against each other, of the shaping die and the reservoir, at low pressure of the fluid work medium or at zero pressure.

Abstract: A die set for press-forming a blank of thin metallic sheet. The die set has a punch and a blank holder. The blank holder has a first bead for restraining an edge of the blank with a constant force. The first bead is disposed further to an inside than a second bead for restraining the edge of the blank with a force that varies during pressing of the blank.

Abstract: An electric staking die that joins a joined material to a shaping material, wherein a bump is formed in the shaping material, the bump is inlaid in a hole made in the joined material and the electric staking die presses a shaping portion that is a portion exserting from the joined material as well as a part of the bump, have a recess on a pressing surface that presses said shaping portion of said shaping material wherein an open hole of said recess is larger than said hole made in said joined material, has been offered. The volume of the recess room is more than the volume of the shaping portion of the shaping material. The manufacturing facility comprises a supporting table, the electric staking die and a control means. A method to carry out the electrical staking operation using the electric staking die is presented as sufficient strength staking.

Abstract: A sheet metal forming process and apparatus using both a mechanical forming step and a superplastic forming step. The mechanical forming step includes using a double-action draw die to create a preform. The preform is then transferred to a superplastic forming tool that uses a superplastic forming process to complete the forming process and create a finished workpiece. Using the mechanical forming step enables rapid creation of a preform having a geometry that reduces overall forming time and provides the ability to draw in additional material to reduce part thinning.

Abstract: Method of preforming and forming a sheet metal article from a preheated blank of sheet metal uses opposing dies including a punch having a punch surface defining a final configuration for the article and a cavity die having a cavity surface defining a preform configuration. The blank is placed between the dies and has a first side surface facing the cavity die and a second side surface facing the punch. A vacuum is applied to the first side of the blank to draw and shape the blank into the cavity die to a preform configuration conforming to the cavity surface. The punch and the cavity die are then closed toward one another and gas pressure is then applied to the first side surface of the blank to press the second side surface against the punch surface to the finish configuration.

Abstract: A method of forming an article such as a helical gear and an apparatus for forming the article are provided. The method includes applying pulsating pressure downward to extruding the work piece and, while the pressure is applied downward, injecting fluid to surround the work piece in fluid. The method eliminates pickling processes and phosphate lube coatings typically required for extrusion and external machining steps subsequently required to remove the coating. Extrusion of a cold net-formed article is thus possible due. An apparatus for carrying out the method is also provided.

Abstract: An apparatus for forming blanks having two thicknesses separated by a blank step includes a forming tool defining a binder surface that is characterized by a tool step, a first region on a first side of the tool step, a second region on a second side of the tool step, and a bead segment having a surface contiguous with the second region. The bead segment is configured to pinch material from a blank into any gap created between the tool step and the blank step caused by misalignment of the blank in the tool, thereby ensuring an effective seal to form the blank against a forming surface.

Abstract: A superplastic forming tool for forming a workpiece to make a part. The forming tool includes a forming die having first and second die members. At least one of the die members having a cavity including a forming surface and a plenum. A plurality of passageways extend between the plenum and the cavity. The passageways allow passage of fluid between the cavity and the plenum.

Abstract: A hydroforming machine characterized by a die 2 having an opening on the upper surface and a fluid tank 2a filled with fluid, a holder 3 being able to hold a periphery part between the die 2 and itself, a punch 4 being movable in a direction into or out for the fluid tank 2a, and a pressure controller 5 controlling the fluid pressure in the fluid tank 2a according to the position of the punch 4.

Abstract: The lower part of a material to be molded forms a lower, seal with a die. A punch applying a molding force to the material forms an upper seal with the perimeter of the die. The space between the upper and lower, seals forms a pressure chamber that is filled with a fluid. As the punch descends into the die, the fluid is pressurized. The lower seal is a complete seal to prevent leakage of fluid into the die. The upper seal is given a clearance with the die that permits controlled leakage of fluid therepast at a rate that limits the maximum pressure in the pressure chamber while permitting the development of an adequate pressure on the material being molded.

Abstract: A system and method for superplastic forming a workpiece. The system includes a superplastic forming cell formed of a plurality of individual stations or modules, each one performing a specific manufacturing step or process on the workpiece. Individual stations include a preheat station, a forming station, a cooling station, a cleaning station and a trimming station. These stations work in conjunction with one another to reduce superplastic forming cycle times and correspondingly increased production times when manufacturing a workpiece using a superplastic forming process.

Abstract: An apparatus (10, 110) and method to form a workpiece (32, 132) into a useful product (28, 128) using a pressurized fluid (14), also termed as “hydroforming”. The workpiece may be a tube or may be one or a plurality of sheets of a material. The apparatus has a chamber (12) adapted to contain a quantity of a fluid, a hydroforming means positioned within the chamber, and means for substantially immersing the workpiece in the fluid before, during and after the hydroforming operation. Dies (16, 18) enclose the workpiece and provide a cavity of desired shape against which the workpiece is expanded by the pressurized fluid. The chamber may be open or closed to the atmosphere during operation and the fluid temperature and/or level may be controlled.

Abstract: A safety pressure relief device comprises an annular flange portion (22), a concave/convex dome portion (24) and a transition portion (26) between the flange portion (22) and the dome portion (24), the transition portion (26) comprising a linear extent (28) extending from the annular flange portion (22) at a first acute angle (?1) to the plane of the flange portion (22), a tangent to the dome portion (24) at its junction with the transition portion (26) making a second acute angle (?2) with the plane of the flange portion (22) which is greater than said first angle (?1), a line of weakness being formed in and around part at least of the linear extent (28) of the transition portion (26).

Abstract: A forming apparatus and method for minimizing wrinkling in the forming of a three-dimensional component from a two-dimensional blank. The forming apparatus includes vertically opposed sets of tools or binders. A first tool or binder apparatus has first and second sets of opposed sides having contoured binder surfaces. A second tool or binder apparatus is mounted in vertically opposed relation to the first binder apparatus, and includes first and second sets of opposed tool or binder segments that have contoured binder surfaces thereon that are complementary in shape to the respective binder surfaces of the first and second sets of opposed sides of the first binder apparatus. One of the first and second sets of opposed binder segments of the second binder apparatus have substantially similar contours and the other have different contours. One of the first and second sets of opposed binder segments of the second binder apparatus is elevated and movable with respect to the other.

Abstract: The hydroforming tool of the present invention comprises a pair of upper and lower tool inserts having open axial ends and defining an elongated cavity there between when the tool inserts are forced together. The upper and/or lower tool inserts are composed of segments that are attached to the upper and a lower base plates, by bolts. Retaining elements, such as pins, are introduced into holes in the base plates and continues into cavities formed in the segmented inserts. This prevents the insert segments from moving during the forming operation. In this way the use of base blocks may be omitted. Sometimes the friction force acting between the base plate and segmented inserts, caused by the high pressure applied to the tool surfaces, is sufficient to prevent the separation of the segments, whereby the segments are kept in place without the use of retaining elements.

Abstract: A pressing member 44 is pressed from the outside against a peripheral wall of a can shell 4 whose interior is maintained at a predetermined pressure by gas, to form a recess-deformed portion 56 having a predetermined shape on the peripheral wall of the can shell 4. Thereby, three-dimensional patterns can be formed by recess-deforming desired portions of the can shell 4 while preventing the strength of the can shell 4 from being deteriorated and preventing the inner surface of the can shell 4 from being scratched or the coating from being damaged, by which outer shape processing with high design performance can be easily applied to the can shell 4 at a low cost.

Abstract: A press of pressure cell type includes a press body part. The press body part comprises a number of plates with the planes of the plates oriented parallel to the planes of the adjacent plates. Each plate has a through hole which has the same center axis as the hole of the adjacent plates. Prestressing bands which induce a compressing prestress acting in the planes of the plates are arranged on an external edge surface of each of the plates.