Abstract: A sprocket for a bicycle drive train comprising an outer ring having external teeth for engaging in a bicycle chain, and an inner ring coaxially disposed with the outer ring and is connected to the outer ring in a rotationally fixed manner. The inner ring has a central opening. A circumferential collar is configured to be integral with the inner ring and projects axially to one side of the inner ring and is configured as a continuous collar. An internal profile having a plurality of radially inward-projecting radial protrusions is provided on the radially inner side of the collar, and an external profile having a plurality of radial depressions, which in number and arrangement correspond to the radial protrusions of the internal profile, is provided on the radially outer side of the collar.

Abstract: A discharge device according to the present disclosure includes a discharge electrode and a voltage applicator that applies a voltage to the discharge electrode and thus causes discharge that is further developed from corona discharge at the discharge electrode. The discharge is discharge in which a discharge path is intermittently formed by dielectric breakdown so as to stretch from the discharge electrode to a surrounding. This discharge can be called leader discharge. This makes it possible to increase an amount of generated active component while keeping an increase of ozone small.

Abstract: In a vehicle body component, a bent portion that is formed in a component main body made of a metal plate is formed of a thickened portion, in which a plate thickness of the metal plate as a material of the component main body is gradually increased. Just as described, since the bent portion, on which stress is likely to be concentrated when a load is applied to the component main body, is formed of the thickened portion, a plate thickness of a portion where the stress is not concentrated can be prevented from being increased more than necessary. This can contribute to improvement of mass efficiency.

Abstract: Systems and methods for forming a workpiece are disclosed. The system may include a fixture assembly for receiving a workpiece having opposing first and second surfaces, first and second tools, and a vibration source configured to vibrate the first and/or second tool. The first and second tools may be configured to move along first and second predetermined paths of motion as the first and/or second tool is vibrated by the vibration source and may exert force on the first and second surfaces to form the workpiece. The method may include vibrating a tool using a vibration source and moving the vibrating tool and another tool along first and second forming paths to form the workpiece. The vibration source may be an ultrasonic transducer and may vibrate the tool at a frequency of at least 1 kHz.

Abstract: The invention relates to a piston (10) for an internal combustion engine, comprising a piston crown (22), a cylindrical piston head (11), which adjoins the piston crown (22), and an at least partially hollow piston skirt (40), which is formed on the piston head (11) on the side facing away from the piston crown (22) and which has two opposite skirt wall segments (50) and two opposite connecting walls (60) that connect the skirt wall segments (50), wherein the connecting walls (60) each have a pin bore (61), wherein the piston head (11) has an annular cooling channel (18), which has at least one inlet opening (28) and at least one outlet opening (30), and the two skirt wall segments (50) widen toward the piston head (11) in such a way that the sector length (L1) of the side of the skirt wall segment (50) formed on the piston head (11) is greater than the sector length (L2) of the side of the skirt wall segment (50) facing away from the piston head (11).

Abstract: The molding method of the present invention configures: a mandrel 2 being a mold for molding the material of a fiber-reinforced plastic 1 and having multiple pieces 21 to 24 adjacent to one another in a longitudinal direction D; and an angle material 3 formed of a material having a linear expansion coefficient approximate to the linear expansion coefficient of the fiber-reinforced plastic, and aligning the pieces 21 to 24 along the longitudinal direction D. The method includes: a mandrel disposing step S2 of disposing the pieces 21 to 24 with gaps G1 to G3 between one another; an angle material disposing step S3 of disposing the angle material 3 on the pieces 21 to 24; and a heating to cure and molding step S5 of molding the fiber-reinforced plastic by heating the material of the fiber-reinforced plastic while aligning the pieces 21 to 24 by the angle material 3.

Abstract: A method and apparatus for forming a hard disk drive base plate with a sequence of progressive forging operations is described. The method may include advancing an initial hard disk drive base plate cut from an extruded sheet through a plurality of stations of a transfer die assembly. The method may also include performing a sequence of forgings on the initial hard disk drive base plate to progressively form parts on a hard disk drive base plate.

Abstract: Provided is a hot upset forging method enabling high shape precision to be obtained. The hot upset forging method includes inserting a workpiece (1), with a bottom face diameter d and a height h satisfying h/d>3, into an insertion hole provided passing through a mold (2) of a height H disposed on an anvil (4), and increasing the diameter of the workpiece (1) while decreasing the height of the workpiece (1) to form a forged material. The mold satisfies the following relationships (1) to (3). (1) A shape of the insertion hole and the cross-sectional shape of the workpiece are substantially similar shapes. (2) The height h of the workpiece (1)?the height H of the mold (2). (3) A largest diameter dl of the workpiece 1, and the maximum inner diameter D of the insertion hole, in the height range of the workpiece (1), satisfy dl<D?dl×1.5.

Abstract: The method of manufacturing a rotor core of an electric rotating machine includes a preliminary shaping step of forming a boss section having a cylindrical portion extending in an axial direction, a disk section extending from one end portion of the boss section in a radical direction and preliminary shape portions of claw sections extending from a periphery of the disk section in the axial direction, a boring step of forming an axial hole extending through the boss section in the axial direction, an ironing step of forming the claw sections, and a sizing step to achieve a necessary thickness and flatness of the boss section. The ironing step is performed with a mandrel having an interference with the axial hole smaller than a boring punch being inserted into the axial hole after completion of the boring step.

Abstract: A method is provided for producing a joint member of a metal joint, such that reduction of assembly manhours and reduction of the thickness and weight can be achieved at the same time without reducing the strength of a product or increasing the cost of production. In the case of a nut-side thin joint member, a metal plate of boron steel obtained by adding boron to low-carbon steel is burred such that the resulting cylindrical body obtains a surface that is sufficient for threading, then a threaded portion having a plurality of threads is formed on that surface, after which, quenching is carried out to increase the strength of the threads so that a nut having sufficient strength can be integrally provided even though the thickness and weight of the joint member are reduced.

Abstract: A steering knuckle assembly and a method of manufacture. The steering knuckle assembly may include a steering knuckle, a spindle, and a snap ring. The snap ring may be disposed in snap ring grooves in the steering knuckle and spindle to inhibit movement of the spindle with respect to the steering knuckle.

Abstract: A forward extrusion forging apparatus includes: a die having a hollow portion whose diameter is reduced at an intermediate position; and a punch that is positioned behind a workpiece placed in the hollow portion, slides in the hollow portion, and extrudes the workpiece ahead of the hollow portion so that the workpiece is forged. An extruding surface of the punch, which extrudes the workpiece, is recessed in a direction opposite an extruding direction in a manner such that a center portion of the extruding surface is most recessed.

Abstract: A method of making a core metal element for a medical guidewire comprising providing a wire of nickel titanium alloy having a length that includes a proximal portion having a first diameter and a distal portion having a second diameter. Applying cold work to the distal portion and not applying cold work to the proximal portion, thereby imparting to the distal portion a third diameter that is smaller than the second diameter; and then applying a reducing process to the wire whereby the proximal portion is reduced to have a fourth diameter that is less than the first diameter.

Abstract: An axle shaft has radially outwardly extending drive fingers which drivingly engage drive slots in a wheel hub cover. The hub cover is rigidly secured to a wheel hub and maintains the axial position of the axle shaft. A shock absorber may be positioned between the drive fingers and the drive slots. The axle shaft may be formed from a hollow tube or a solid shaft by cutting an end portion of the shaft and deforming a cut section radially outwardly to form a drive finger.

Abstract: A recip blade includes a blade body, a tang, a distal end, a cutting edge, and a rib. The tang is located an end of the blade body. The distal end is located at an opposite end of the blade body relative to the tang. The cutting edge extends in a lengthwise direction at least substantially between the tang and the distal end. The rib extends along at least a portion of the blade body. The rib and the cutting edge are spaced from one another by a heightwise-extending distance. A method includes: (i) providing a recip blade including the blade body, the tang, the distal end, and the cutting edge; (ii) forming the rib by increasing a widthwise-extending thickness of the blade body at the rib in comparison to a widthwise-extending thickness of the blade body at an adjacent portion of the blade body.

Abstract: A nut is formed by a die forging process in which a die used for the die forging process is released in a direction along the direction of the axis of rotation of the nut.

Abstract: A method for the production of a cold-rolled profile having at least one thickened profile edge made of a metal strip is provided. For this purpose the metal strip is guided through at least one clamping nip formed by at least one guide roll and at least one lateral edging roll, wherein the roll axis of the guide roll is disposed parallel to the web level of the metal strip, while the roll axis of the edging roll is disposed transverse to the roll axis of the guide roll, and is lined up at an angle to the strip level such that in addition to the upsetting force exerted by the edging roll onto the strip edge a clamping force is also applied that acts on the side of the metal strip facing away from the guide roll. The edging roll may be configured in steps, and surrounds the web edge at least on the side of the metal strip facing away from the guide roll.

Abstract: A method for achieving a higher stress corrosion cracking resistance for steel components of corrosion resistant, austenitic steel having an outer oxide layer, especially a chromium oxide layer, especially steel components in the form of steel sheets, steel pipes or steel rods, as well as for weld seams connecting austenitic steel components, wherein the increased stress corrosion cracking resistance is achieved by introducing compressive stresses into an outer layer of the steel component covered outwardly by the oxide layer, respectively into an outer layer of the weld seam, wherein the compressive stresses are introduced by areal pressure exertion on the respective outer layer.

Abstract: A method for manufacturing a high-strength motor vehicle door hinge from a steel plate blank includes a cold heading step of forming a cylindrical bulging portion at one end of the blank in the width direction, a shaft hole forming step of forming a shaft hole in the cylindrical bulging portion, and a shaft hole finishing step. In the shaft hole forming step, a shaft hole is formed using a first punch having a top end with a shape of a cone and a first die having an inner wall with a gap volume relative to the outer circumferential surface of the cylindrical bulging portion of the blank.

Abstract: Joining process, joined article, and process of fabricating a joined article are disclosed. The joining process includes providing a consumable electrode comprising a first material and a second material, melting the consumable electrode by a current-induced melting or remelting, and re-solidifying the first material and the second material to form a dissimilar ingot having a first region being a re-solidification of the first material and a second region being a re-solidification of the second material. The joined article includes the first region and the second region; the dissimilar ingot at least partially defines the joined article. The process of fabricating includes providing the dissimilar ingot, positioning the dissimilar ingot within a die, and applying force from the die to compress the dissimilar ingot, thereby forming the joined article.

Abstract: The invention relates to an Integrated Valve Sleeve for a spool and sleeve valve and solenoid housing for accepting a solenoid assembly. The apparatus is integrated insofar as it is fashioned from one piece of malleable material through a cold-forging process, thus avoiding the structural weakness endowed in similar assemblies formed through welding processes and the like.

Abstract: Generally, the present disclosure relates to a composite structure having at least three different components, and a process for manufacturing the same. The structure may be, but need not be, a metal coin. In one embodiment, the structure comprises an outer ring and two inserts stacked on top of each other and disposed within the outer ring. The outer ring and each of the two inserts are made of different materials. The outer ring and each of the inserts are locked together by a plurality of recesses formed in outer circumferential surfaces of the inserts. The structure may further comprise at least one interlayer disposed between the two inserts for adhering the two inserts to one another. The three major components and the interlayer may be made into a single structure by a striking force during coining or striking.

Abstract: Medical devices that include a Ni—Ti ternary alloy and methods for their manufacture. The medical devices described herein include at least one part fabricated from the Ni—Ti ternary alloy. In the Ni—Ti alloys, the ternary alloying element is selected to be compatible with Ni—Ti. Example Ni—Ti ternary alloys include nickel (Ni), titanium (Ti), and one or more of tantalum (Ta), hafnium (Hf), vanadium (V), zirconium (Zr), scandium (Sc), or yttrium (Y). By virtue of their compatibility with Ni—Ti, additions of the ternary alloying element(s) may substitute for titanium in the Ni—Ti phase up to the solubility of the ternary element and the remainder can exist as a second phase whose mechanical properties resemble that of the pure ternary element and whose elastic modulus exceeds that of the Ni—Ti matrix.

Abstract: There is provided a method of manufacturing an outwardly flanged metal member, by which a metal member having outward flange portions which extend radially outwardly from a plurality of positions along a circumferential direction on an outer peripheral surface can be formed without a flash, or with a reduced amount of a flash. While surrounding a periphery of a metal blank 15 by a stationary die 21 and a movable die 22 and butting a distal face of the movable die 22 and a distal face of the stationary die 21, an axial end face of the blank 15 is plastically deformed by pressing the axial end face with the punch under a warm or hot condition to form the outward flange portions 7a by filling flange molding cavities 32 with a portion of the blank 15.

Abstract: Embodiments of the present disclosure describe interposer apparatus and methods for their fabrication and use. In some embodiments, an interposer includes a first frame having a first opening, a second frame having a second opening, and a body frame, disposed between the first frame and the second frame. A first end portion of a pin is disposed in the first opening, a second end portion of the pin is disposed in the second opening, and a body portion of the pin is disposed in the body opening between the first and second frames. Other embodiments may be described and/or claimed.

Abstract: A method for assembling a part of a metal material and a part of a composite material, the junction of the two parts being achieved through a fastener having a substantially constant section and received in a first hole formed in the part of a metal material and a second hole formed in the part of a composite material. According to the disclosed embodiments and before assembling the aforementioned parts, the method includes: an expansion step for generating a field of compression stresses at the periphery of the first hole and locally in the material constituting the part of a metal material using an expansion tool; a single boring step for making the first hole and the second hole with a diameter Øfinal substantially larger than the diameter of the fastener in order to leave a gap between the inner walls of the holes and the outer surface of the fastener; and an assembling step for placing the fastener inside the holes for maintaining together the metal part and the composite part.

Abstract: The clutch hub includes a sheet-metal hub member which has an axial member projected from the center of its plate surface, and also includes an annular armature which is fixed to an outer peripheral portion of the axial member. First mounting the axial member of the clutch hub downward on a support member and thereby elastically supporting the end surface of the armature by the support member; holding the axial member of the clutch hub using a chuck; locating a fixing member just under a portion of a maximum runout portion of an inner hub; contacting a cylindrical end surface of a pressing member with an upper surface of the inner hub using pressure; and plastically deforming the inner hub by a pressing force of the pressing member using the locating portion of the fixing is member as a fulcrum, which thereby corrects an inclination of the axial member.

Abstract: An apparatus for collapsing an expandable stent can include a plurality of movable members braided together to form a tubular member or main body portion. The movable members can at least partially define a lumen in the main body portion. The main body portion can be adapted to circumferentially apply an inward force as the diameter of the main body portion is reduced. The diameter of the main body portion can be reduced by moving opposing ends of the main body portion away from each other. An expanded expandable stent can be collapsed by positioning the stent inside the lumen of the main body portion and pulling opposing ends of the main body portion apart. An intermediate layer can be provided between the stent and the main body portion to reduce shear stresses and point forces on the stent.

Abstract: A spacer for a sealed unit is formed of a stretched elongate strip of material, such as metal. The elongate strip is longitudinally stretched, causing a reduction in the thickness of the material. Stretching is performed by applying a tension across a segment of an elongate strip. The tension can be applied to the elongate strip by passing the elongate strip through at least two spaced sets of rollers. A first set of rollers operating at a first speed engages with the elongate strip and a second set of rollers operating at a second speed applies a tension to the elongate strip to cause stretching of the material. Corrugated rollers can also be used to form the material into an undulating shape.

Abstract: Methods and apparatuses for manufacturing a press-molded product with a preform including a pair of side wall portions and a connecting wall portion are taught. The preform is pressed with a mold until at least one wall portion is bent toward a gap within the mold, and a plate thickness is increased at the at least one wall portion and the connecting wall portion by pressing other wall portions.

Abstract: A junction box for a solar panel comprises a housing, a lid, a first connector and a second connector. The housing comprises sidewalls and a top wall defining an interior space. The first coupling comprises a first contact element and the second coupling comprises a second contact element. Said contact elements penetrate at least one of the sidewalls, so that the contact elements provide an electrical contact from external contact elements to internal contact elements, such as solder tails. Internal contact elements are arranged at least partially in said interior space. The top wall comprises an opening extending only partially in said top wall. Said opening is located such in the top wall that access to said solder tails in a substantially perpendicular direction to the surface of a solar panel for connecting the solder tail to the solar panel is provided.

Abstract: An apparatus is provided which makes a border wire having a rectangular cross-section. The apparatus is adapted to receive a roll of wire having a circular cross-section, straighten the wire and change the cross-section of the wire to rectangular. The reconfigured wire is then accumulated, passed through another straightener, cut to size and then bent into a rectangular configuration. Opposed ends of the piece of wire having a rectangular cross-section are welded together to complete the border wire. The apparatus has an ejector which removes the completed border wire from the apparatus.

Abstract: A workpiece enlarging method is provided, by which an enlarged portion can stably be formed on a portion of a workpiece such as a shaft member, and a drive force required to form the enlarged portion can be reduced. The workpiece enlarging method forms the enlarged portion on the workpiece (W) by applying, with respect to the workpiece (W), alternating shear energy in a transverse direction thereof so as to suppress deformation of the workpiece (W) within an elastic limit while applying compression energy that produces compressive stress equal to or greater than an initial yield strength to increase internal energy of the workpiece (W), thereby decomposing a portion of the increased internal energy by the alternating shear energy and deforming and enlarging the enlargement intended area of the workpiece (W) with the assistance of the decomposed energy obtained by the decomposition.

Abstract: A bonding wire is provided containing a wire core made of a first material containing a metal and a wire jacket that envelopes the wire core and is made of a second material containing a metal. The wire core and the wire jacket are made of different metals and the bonding wire has an aspect ratio of no more than 0.8. The bonding wire efficiently prevents damage to bonding surfaces during the bonding process and short-circuiting during the use of corresponding sub-assemblies.

Abstract: A steel material which is suitable for hot press working or hot three-dimensional bending and direct quench and which can be used to manufacture a high-strength formed article with sufficient quench hardening even by short time heating at a low temperature has a chemical composition comprising, in mass percent, C: 0.05-0.35%, Si: at most 0.5%, Mn: 0.5-2.5%, P: at most 0.03%, S: at most 0.01%, sol. Al: at most 0.1%, N: at most 0.01%, and optionally at least one element selected from the group consisting of B: 0.0001-0.005%, Ti: 0.01-0.1%, Cr: 0.18-0.5%, Nb: 0.03-0.1%, Ni: 0.18-1.0%, and Mo: 0.03-0.5% and has a steel structure in which the spheroidization ratio of carbides is 0.60-0.90.

Abstract: A method for preventing or arresting the development and propagation of cracks in the material surrounding a fastener. The method includes introducing compressive residual stresses in the material surrounding the fastener. The compressive residual stresses offset the high residual tensile and applied stresses which the material may be subjected to in operation and thereby prevent or arrest the development of cracks. Using the output of a sensor, the surface treatment apparatus is positioned relative to a fastener. A compression tool is impinged against the surface of the material adjacent to the fastener and rotated around the perimeter of the fastener thereby inducing a zone of compressive residual stress.

Abstract: A method of forming a metal container comprises: curling outward a top edge of the metal container to form a curl and expanding a diameter of a first section of the metal container to form a first expanded section; wherein at least part of the first expanded section is below the curl. In some embodiments, the steps of curling outward a top edge of the metal container to form a curl and expanding a diameter of a first section of the metal container to form a first expanded section are performed in a single stroke of a single die. In some embodiments, the step of expanding a diameter of a first section of the metal container to form an expanded section is performed after the step of curling outward a top edge of the metal container to form a curl.

Abstract: A latch needle includes a pivot pin connected with the latch in a torque-proof manner, said pivot pin having mirror-symmetrically shaped bearing heads (29, 30) on both sides of the latch shank (20). The bearing heads (29, 30) are produced by plastic deformation (i.e., axial upsetting of a pin (27)) and have a cylindrical exterior shape.

Abstract: A process for making an article of a titanium alloy having ?? phase as a major phase according to the present invention includes providing a work piece of a titanium alloy consisting essentially of 7-9 wt % of molybdenum and the balance titanium and having ?? phase as a major phase; and cold working at least a portion of the work piece at room temperature to obtain a green body of the article, wherein the cold worked portion of the green body has a thickness which is 20%-80% of that of the at least a portion of the work piece, and the cold worked portion has ?? phase as a major phase.

Abstract: The present invention provides a manufacturing method of a bearing ring member such as an outer ring comprising an installation portion on the outer peripheral surface and a double row of outer-ring raceways on the inner peripheral surface, in which a raw material is processed to obtain a final stage intermediate member through a first upsetting process, a forward-backward extrusion process, a second upsetting process, a burr removing process, and a punching process, wherein a movable die which leaves a stationary die in the final step is used in the second upsetting process, and the excess metal material is moved toward outside in the radial direction to a portion which become the installation section and a burr formation section, exposing a high pure metal material at least in a portion where the load of rolling bodies acts so as to ensure the rolling fatigue life of the both of outer-ring raceways.

Abstract: Provided is a manufacturing method of an outer ring (3) of a back-to-back arrangement double-row angular ball bearing from a raw material (10) comprising a upsetting (A to B), a backward extrusion process (C to D), a punching (D to E), a rolling (E to F) and a finishing, wherein an outer diameter of a first intermediate material (11a) produced by the upsetting is equal to or smaller than an inside diameter of an inner periphery large diameter portion (18) of the inner circumference of a die (13) used in the backward extrusion process and larger than an inside diameter of an inner periphery small portion (19) of the die (13), and in a condition with the first intermediate material (11a) sitting on the inner periphery inclined portion (20) of the die (13), the intermediate material (11a) is pushed toward a base of the die (13) by a punch (14), to thereby the middle metal material (29) with the highest cleanliness of the raw material (10) is exposed to the two outer ring raceways (2) of the outer ring (3).

Abstract: The present invention is premised upon method of manufacturing rolled pierce nuts having a predetermined profile from a metal rod, more particularly to a method and apparatus delivering greater manufacturing flexibility through the use of multiple stations with flexible inputs and outputs.

Abstract: The disclosed invention specifies: 1) a metal or alloy with specific characteristics of its Deformation-induced Volumetric Microstructural Imperfections (DIVMI), 2) a method to measure these imperfections, and 3) a method to control these imperfections in a way that enhances one or more of strength, ductility, and the high cycle fatigue endurance limit of metals and alloys. The invention recognizes that all deformation-processed metals or alloys contain DIVMI and that through Severe Plastic Deformation processing one can minimize the characteristics of DIVMI that limit mechanical properties. Application of the methods to measure and control imperfections allows one to produce metals and alloys with strengths approaching the theoretical limit of strength.

Abstract: A method of forming a metal container comprises: narrowing a first top section of the container in at least one narrowing step, wherein after narrowing the first top section, the first top section has a first top section minimum outer diameter; and narrowing a second section of the metal container after narrowing the first top section, wherein after narrowing the second section, the second section has a second section minimum outer diameter; wherein the second section is below the first top section minimum outer diameter and wherein the second section minimum outer diameter is larger than the first top section minimum outer diameter. In some embodiments, the second section is below the first top section minimum outer diameter. In some embodiments, the second section of the metal container is necked with a necking die.

Abstract: A method of making sputter targets using rotary axial forging is described. Other thermomechanical working steps can be used prior to and/or after the forging step. Sputter targets are further described which can have unique grain size and/or crystal structures.

Abstract: A product including a top surface part, a vertical wall part connected to an end of the top surface part and a corner part interposed between the top surface part and the vertical wall part is manufactured by flowing a material of the corner part toward the top surface part while applying a pressing force on a workpiece.

Abstract: Any of various features of a workpiece are forged by a common set of tools. The feature is incrementally forged as the tool set is moved to successive forging locations on the surface of the workpiece. One of the tools is used to plasticize and extrude a portion of the workpiece while one or more of the other tools are used to form dams that contain and shape the extruded portions.

Abstract: A can or container reformed from an existing open ended can adds additional volume and integral thread portions to form a recloseable can. An existing can is inverted, drawn to increase the volume, an end wall pierced and reformed into an outwardly curled lip, thread portions formed along a perimeter portion of the can body adjacent a first end, and a new end seamed to the original open, second end of the can. A cap with thread lugs cooperates with the thread portions on the external perimeter of the reformed can to originally and subsequently reseal the can once the can has been opened.

Abstract: The invention relates to a method of providing a solenoid housing, including the steps of providing a solid cylinder of malleable material having a first part and a second part; reducing a diameter of the first part of the cylinder to be less than a diameter of the second part of the cylinder; compressing the second part in an axial direction toward the first part, resulting in a flattened disc generally perpendicular to the first part; raising at least a part of a perimeter of the flattened disc in a direction toward the first part for defining a raised wall; and wherein the first part, second part, and raised perimeter are all integrally connected as a single piece.

Abstract: In a method of making through-passages in a perforated U-shaped sheet metal part, an inner core is positioned between confronting legs of the sheet metal part in an area of holes, and a support bar is inserted through one hole into the sheet metal part for support of a backside of the inner core. A shaping punch is inserted through another opposite hole into the inner core, thereby forming an inwardly directed collar. After retracting the support bar and the shaping punch and transferring the sheet metal part to replace the first inner core with a second inner core, a centering bar is inserted through the collared hole into the sheet metal part to center the sheet metal part in relation to the centering bar and to support a backside of the other inner core. A further shaping punch is then inserted into the second inner core through the first hole, thereby forming an inwardly directed collar so that the two collars are aligned and form through-passages.