Abstract: A side wall of a pipe is clamped by a first die and a second die to thereby clamp the pipe. The first die and the second die are made to approach each other while an end of the pipe is pressed toward the first die by the third die along a longitudinal direction of the pipe, to thereby form a spool between the first die and the second die. In a state where the spool is clamped by the first die and the second die, the third die is separated from the pipe along the longitudinal direction of the pipe so as to separate the second die and the third die from each other. Clamping of the pipe is released such that the first die and the second die separate from the side wall of the pipe, to thereby unclamp the pipe.

Abstract: A composite hose is constructed to have an outer peripheral portion and an inner peripheral portion. The outer peripheral portion includes an elastic layer and a reinforcing layer provided on an outer periphery of the elastic layer. The inner peripheral portion includes a corrugated metal tube which is provided with a corrugated portion formed with corrugation hills and corrugation valleys. A distance between the reinforcing layer and tops of the corrugation hills of the corrugated metal tube is designed 0.27 mm or less.

Abstract: Process for producing a pressure vessel having an enveloping body which occupies an arch shape in its predetermined installation position. The enveloping body has pillow-shaped portions which are connected to one another by stamped transitions at the inner diameter area of the enveloping body. The enveloping body for the intended installation position is placed with its inner diameter area one-sidedly on a die having a raised wedge-shaped profile. A designated outer diameter area of the enveloping body contacts a supporting surface, and the enveloping body is filled with a pressure medium so that the enveloping body is tensioned on the die and, in so doing, is plastically deformed in the area of the wedge-shaped profile.

Abstract: Methods of forming a lined tubular member are described herein. A method includes forming at least one corrugated portion in a conduit having at least one substantially tapered end to form a corrugated conduit, providing the corrugated conduit to a tubular member; and expanding the corrugated conduit while the corrugated conduit is inside the tubular member.

Abstract: Insulating element for expansion compensation device and method for manufacture thereof, of the type used in solar energy collector absorber tubes, being formed by a single piece in the form of a ring and with a bellows-like end portion, which is filled with rock wool or other equivalent insulating material, so as to create a hot air chamber which minimizes heat losses.

Abstract: A bulge forming method includes arranging a raw material tube inside a die having an inner surface shape, in which plural crest portions and root portions are alternately formed, and providing a rod inside the raw material tube in the axial direction of the raw material tube, and the rod has a pressurized liquid supply opening. The bulge forming method further includes providing a pair of sealing portion having the pressurized liquid supply opening therebetween, and the sealing portions seal a space between the raw material tube and the rod. The bulge forming method further includes moving the rod in the axial direction while applying compressive stress to the raw material tube in the axial direction and supplying a pressurized liquid from the pressurized liquid supply opening into the raw material tube, whereby the raw material tube is formed into the shape of the inner surface of the die.

Abstract: A metallic bellows is manufactured by a first step of bulging a straight raw pipe into a primary formed body having formed on a periphery thereof a corrugated bellows section, and a second step of subjecting at least one of crest portions and trough portions of the bellows section of the primary formed body to roll machining by means of a pair of forming rolls.

Abstract: A corrugated conduit and method of expanding to form a lined tubular member are described. In some embodiments, a corrugated conduit may be expandable. The corrugated conduit may be inserted into a tubular member and hydraulically or otherwise expanded against walls of the tubular member to strengthen and/or seal the tubular member when the corrugated conduit is expanded in the tubular member. In certain embodiments, the tubular member is a drill stem.

Abstract: In a method and a device for non-rotatably connecting a hollow shaft with at least one component located on the hollow shaft with which the component is positioned with clearance on the hollow shaft and is fastened thereon in a certain position by eliminating the clearance, the clearance being eliminated by expanding the hollow shaft using a joining tool that passes through at least part of the hollow shaft, and the joining tool including at least one first shaping element and at least one further shaping element, and the shaping elements being movable relative to each other, so that the motion of the shaping elements relative to each other causes an at least partial expansion of the hollow shaft. A design of this type has the advantage, in particular, that the joining tools cause the hollow shaft to expand only at the necessary points.

Abstract: A lined conduit formed by decorrugating a corrugated liner conduit inside a first conduit is described. A method and apparatus for forming the lined conduit are also described. The corrugated liner conduit may be positioned inside the first conduit. Each end portion of the corrugated liner conduit may be coupled to a hydraulic expander. Each hydraulic expander may include a hydraulic cylinder. Each hydraulic cylinder may include a piston rod with an opening along the length of the piston rod. The corrugated liner conduit may be evacuated through a valve assembly coupled to the passageway in one of the piston rods. The evacuated corrugated liner conduit may be pressurized with fluid from a fluid source coupled to the valve assembly. Pressurizing the corrugated liner conduit may expand corrugations in the corrugated liner conduit to form a decorrugated liner in the first conduit.

Abstract: In some embodiments, a variable stiffness structure is provided having constant stiffness material layers and variable modulus material layers arranged in alternating layers. The variable modulus material layers have a material with a changeable elastic modulus in response to an applied energy field so as to allow reversible coupling and decoupling of stress transfer between successive layers of the constant stiffness material layers to provide a change in a bending stiffness of the variable stiffness structure. The constant stiffness material layers may include segmented portions. The constant stiffness material layers may have segmented portions arranged such that successive layers of the plurality of constant stiffness material layers have overlapping segmented portions. The variable modulus material layers may have shaped structures, for example, corrugation, pillars, striations, tubular, or honeycomb configurations.

Abstract: The invention relates to a heat exchanger, especially a heat exchanger for motor vehicles, comprising a bank of tubes through which a gaseous medium flows and around which a liquid coolant flows. The ends of said tubes are received in tube plates and are connected to the same in a material fit. The inventive heat exchanger also comprises a housing jacket which surrounds the bank of tubes and is connected, at the end thereof, to the tube plates. A coolant flows through said housing jacket. The tubes, tube plates and housing jacket are produced from a heat-resistant and corrosion-resistant metallic alloy. According to the invention, the housing jacket comprises at least one surrounding expansion flange.

Abstract: A metallic bellows is manufactured by a first step of bulging a straight raw pipe into a primary formed body having formed on a periphery thereof a corrugated bellows section, and a second step of subjecting at least one of crest portions and trough portions of the bellows section of the primary formed body to roll machining by means of a pair of forming rolls.

Abstract: A method for manufacturing a driveshaft for use in a vehicle drive train system that is axially collapsible in the event of a collision to absorb energy. A workpiece, such as a hollow cylindrical tube, is deformed by hydroforming to provide an axial collapse initiation zone. The axial collapse initiation zone can be defined by a plurality of axially extending undulations or corrugations that are formed in a central portion of the tube. The axial collapse initiation zone is designed to accommodate the transmission of torque through the driveshaft without any deformation under normal operating conditions. However, if a relatively large axial force is applied to the front and rear end portions of the driveshaft, the axial collapse initiation zone is designed to allow relative axial movement to occur between the front and rear end portions of the driveshaft. Such collapsing functions to absorb energy during a collision, thereby providing additional safety to the occupants of the vehicle.

Abstract: A method for expanding tubular blanks includes pre-expanding or initially expanding a section of the tube by forcing a punch into an open end of the tube. The punching process may be repeated to achieve up to approximately 50% expansion from the original configuration of the blank. Then, the same pre-expanded section can be further expanded by hydroforming such that the blank is filled with pressurized fluid to achieve further expansion of the initially expanded section up to approximately 100% expansion from the original configuration of the blank. As a final step, the open end of the expanded tube may be cut to its ultimate shape.

Abstract: A process for the production of tubular structural parts fabricated from PGM materials and having circumferential undulating bulges by forming from smooth-walled tube pieces. A smooth-walled tube piece (1) is inserted into a cylindrical forming die (2) with an internal diameter that corresponds substantially to the external diameter of the tube piece and that has radial undulating recesses (3). This die is provided at both axial ends with a press tool (4,5) that tightly seals the tube ends. The space that is thus formed is completely filled with an hydraulic fluid (6), and an hydraulic internal pressure is then produced by exerting an axial compression via the press tools (4,5) in such a way that under simultaneous shortening of the tube piece bulges (7) are formed in the wall of the latter that correspond to the recesses (3) of the forming die (2).

Abstract: Providing a method of hydroforming a tube where the hydroformed diameter is less than the tube length and a hydroforming die having two or more die members having an internal shape same as the tube shape and an internal cavity having the desired formed shape. Where the said die members are movable to an opened and closed position such that the tube is placed inside the die members cavities and the tube ends are sealed and hydraulic pressure source is connected to the interior of the tube and thereby expanding the tube so as to conform to the shape of the said die members cavities. And where the directions of opening and closing of the said die members are in the direction of the said tube axis such that the amount of force necessary to hold the die members in a closed position during said step of expanding, is kept to a minimum.

Abstract: A process for producing a component for reducing the effect of an external mechanical impact, of the type which comprises an essentially tubular metal element which has a jump in its cross section which is such that under the influence of an axial load it can be turned at least partially inside-out as a result of plastic deformation, by means of which process the tubular element is formed by hydroforming from a piece of tube which has a cross section which is constant along its length, during which process part of the length of the cross section is increased in size, and the transitions in the cross section cover a short distance, and during the hydroforming an axial pressure on the piece of tube which is being deformed is set to be such that the transitions in cross section adapt to an S-shape.

Abstract: A manufacturing method for manufacturing a bellows having pleat walls with S-shaped profiles comprises a primary forming process for forming a formed bellows, a pressing process for compressing the formed bellows in the axial direction, and a stretching process for pulling the compressed bellows in the axial direction, thereby obtaining desired pitches and free length. After the stretching process is carried out, the bellows is subjected to an annealing and ageing heat-treatment process. An apparatus for manufacturing the bellows comprises a pair of molds that have their respective forming surfaces in shapes corresponding individually to the pleat walls. The die is slightly retreated away from the pleat walls just before the dies open in the diametrical direction after the pleat walls are formed.

Abstract: A method and apparatus for producing a shaft from a piece of tubing having at least one bulging portion. The method enables shafts with bulging portions to be cheaply and practicably produced. The piece of tubing bears radially against a portion adjoining the zone of the bulging portion to be produced. The piece of tubing is subjected to internal pressure which is maintained throughout the entire molding operation. The piece of tubing is acted upon by an axially operative compressive force co-operating with the internal pressure so that a portion of tubing adjoining the radially borne portion is upset so that the external diameter of the upset piece of tubing is larger than the external diameter on the unupset piece of tubing. A molding tool, having a hollow portion corresponding to the final shape of the bulging portion to be produced, is then applied to the upset piece of tubing. The bulging portion is formed by the application of radially operative compressive forces by means of the molding tool.

Abstract: The components of a hydroforming machine include a die housing for containing a plurality of dies, a water distribution system, and a means for compressing the dies. The dies includes first and second die plates which are secured together by a key inserted into aligned keyways in each of the first and second die plates. The key is non-rotatable, such as being square shaped, rectangular, triangular, or the like for eliminating interference with adjacently positioned keys. The pins and links coupled to the die plates are held in position by keepers, which are elongated narrow pieces of metal positioned substantially parallel with the die plates and having a width approximately equal to the width of the die plates for allowing a person to view between the adjacent dies and into the die housing for observing formation of the bellows during the hydroforming process.

Abstract: A manufacturing method for manufacturing a bellows having pleat walls with S-shaped profiles comprises a primary forming process for forming a formed bellows, a pressing process for compressing the formed bellows in the axial direction, and a stretching process for pulling the compressed bellows in the axial direction, thereby obtaining desired pitches and free length. After the stretching process is carried out, the bellows is subjected to an annealing and ageing heat-treatment process. An apparatus for manufacturing the bellows comprises a pair of molds that have their respective forming surfaces in shapes corresponding individually to the pleat walls. The die is slightly retreated away from the pleat walls just before the dies open in the diametrical direction after the pleat walls are formed.

Abstract: A tube member is placed in a die having a plurality of nodules formed in the cavity thereof. A chamber is formed between a mandrel and end piece within the tube. The mandrel is positioned adjacent a first of the nodules and the chamber is pressurized during a hydroforming cycle to form a node on the tube by simultaneously expanding a portion of the tube outward and feeding the tube linearly into the die cavity. A mechanism for feeding the tube linearly is external to the die cavity and has a member in abutment with one end of the tube. During a positioning cycle, the pressure in the chamber is reduced and the mandrel is moved longitudinally within the tube to a position adjacent the next sequential nodule to permit a repeat of the hydroforming cycle. In one embodiment of the hydroforming process, a mandrel is positioned into the tube from each tube end and a feed mechanism is disposed adjacent each tube end. This permits the sequential simultaneous hydroforming of pairs of nodes on the tube.

Abstract: A method and a device for manufacturing a tubular hollow body with increased diameter portions which are arranged at a distance from each other using the internal high pressure deformation process. Initially an internal portion of the hollow body is sealed off at one end thereof and is supported on the inside at the other end thereof and in this internal portion is formed an increased diameter portion by a hydraulic internal high pressure while axially advancing the hollow body, and subsequently, after axially reversing the hollow body within the shaping tool, another increased diameter portion is manufactured in the same manner.

Abstract: Apparatus and method for mechanically and hydroform reconfigurating an elongated tubular workpiece in an elongated cavity between upper and lower tool subassemblies each composed of a plurality of independent tool segments movable axially, relative to the cavity axis, together or spaced from each other, and independently movable transversely of the cavity, usually vertically, in sequence, to grip the end portions of the workpiece while its ends are flared with tapered mandrels, and after the workpiece is filled with liquid, offset deform one workpiece portion while the tool segments are spaced apart and with axial infeed of workpiece material, then offset deform another portion with further axial infeed of workpiece material. Hydroforming pressure is then applied to partially expand the workpiece.

Abstract: The present invention relates to a method for forming a pipe with a corrugated wall by means of the electroforming technique. The method comprises the stage of forming, possibly partial, on the circumference of the pipe over a length of about one pitch of the corrugation. The corrugated deformation of the pipe is obtained by step-by-step forming after moving the forming mandrel longitudinally in the pipe. The invention also relates to a device for forming a corrugated pipe. In a variant, the device comprises a cylindrical mandrel on which a groove deepens over a circumference portion and continues at the depth of the corrugation to be formed.

Abstract: A method for forming metal parts from superplastic metal alloys uses axial compression of the blank starting material. A blank of the superplastic metal alloy is enclosed within a die press. The blank is generally tubular, although not necessarily circular, and has an aperture at each end. The ends of the blank are enclosed within correspondingly shaped sections of a cavity within the die press, while the center of the blank is disposed within a central cavity defining a desired shape of the metal part to be formed. Each end of the blank is then sealed with a ram or stop member, and the die press and blank are heated to a forming temperature that is within the superplastic temperature range of the metal alloy. Gas is supplied under pressure to the inside of the blank to produce an outward pressure urging the blank to deform outwardly within the central cavity of the die press.

Abstract: Herein disclosed is a wrinkled pipe manufacturing apparatus in which an elastic member is inserted into a pipe to be worked and is pushed from at least one side so that it may be radially bulged to form an annular bulge on the circumference of the pipe and in which a punch and a chuck disposed around the circumference of the pipe are axially moved relative to each other to form a wrinkle from the annular bulge. The apparatus comprises: first and second mandrels held over a bed to move freely in the axial directions along the upper face of the bed and adapted to bear the pipe on their circumferences; first drive means for driving the mandrels in the axial directions; an elastic member arranged in the pipe and between the leading end faces of the first and second mandrels; second drive means for moving a punch and a chuck; and guide means for guiding the chuck and the punch in the axial directions on a concentric plane of the axis.

Abstract: A bellows pipe is manufactured, with an elastic body pinched between a collar and a stopper inside a raw pipe being deformed, by pressing the elastic body as to expand radially such that a circumferential portion of the pipe changes to an annular convex portion, pinching and compressing the annular convex portion by a chuck and a punch to form a bellows portion, and shifting the pipe a given distance while pinching the bellows portion by the chuck. A plurality of bellows portions are successively formed in the pipe by repeating the foregoing deforming steps.

Abstract: An appratus and method for manufacturing a pulley having a generally V-shaped groove therein is provided. The apparatus includes a press section and a molding section. The starting material for forming the pulley is a ring-shaped workpiece which is preferably composed of a bendable metal. The apparatus clamps the workpiece about a central annular portion thereof. Other parts of the apparatus bend upper and lower annular portions of the workpiece radially outwardly, thereby forming a V-shaped groove. The pulley is formed by a single thrusting motion of the press section. The bottom portion of the V-shaped groove has a uniform thickness which is not thinned by the action of the press.

Abstract: A bellows pipe is manufactured from a raw pipe, with an elastic body pinched between a movable core and a fixed core inside the raw pipe, by compressing the elastic body by axially moving the movable core to form an annular convex portion in the raw pipe, changing the annular convex portion to a bellows portion by axially moving a punch to press the annular convex portion, pinching the bellows portion between a chuck and a chuck inner block assembled therein, shifting the pipe a given distance by axially moving the chuck and chuck inner block holding the bellows portion therebetween, and repeating the foregoing steps. Therefore, a small-diameter raw pipe of smaller than 16 mm diameter can be deformed, the outer diameter, pitch, etc. of a bellows portion can be freely set, the elastic body is worn little.

Abstract: A first insert member and a head member are inserted in a cylindrical metal material. A liquid pressure chamber is defined in the material by the first insert member and the head member. First and second dies are situated corresponding to the head member and the first insert member, respectively. When a pressurized liquid is fed into the liquid pressure chamber, that portion of the material situated between the first and second dies bulges outward. As the first and second dies are driven to approach each other with the bulging portion between them, a pleat with a U-shaped section is formed.

Abstract: After a metallic cylindrical tube is bulged to form a bellows with a circular cross section, this bellows is ovalized to form a bellows with an oval cross section. For this reason, an inexpensive round tube (cylindrical tube) can be used as the material for a bellows with an oval cross section and it is unnecessary to use an expensive oval tube. Accordingly, a bellows with an oval cross section can be produced at low cost.

Abstract: A method for the manufacture for the tubes or shafts of a composite material and having a low weight, whereby a blank of a material that can be pressformed and which has a substantially even thickness of material is subjected to isostatic pressing on or in a formation tool thereby providing a shell or a liner (15) of an intended shape and profile and having a mainly by substantially thickness of material, and on or in said shell or liner (15) another material is applied and is bound, for instance a highstrength material like glassfiber, carbon fiber or aramide fiber, so that the liner (15) and said other material (17) provide a solid integral composite tube or composite shaft.

Abstract: A fluid pressure actuator construction and method of making the same are provided, the method comprising the steps of forming a housing with an annular surface, securing an outer peripheral portion of a flexible diaphragm to the annular surface to define a fluid chamber with the housing whereby certain pressure differentials acting across the diaphragm cause movement thereof relative to the housing for actuation purposes or the like, and before the step of securing the diaphragm disposing a compression spring in the chamber to act between the housing and the diaphragm to tend to move the diaphragm in a direction away from the chamber, disposing a backup plate in the chamber so as to engage against the side of the diaphragm that faces the chamber, causing the spring to have one end thereof bearing against the backup plate, and forming the diaphragm to comprise a lamination having a polymeric layer defining the side thereof facing away from the chamber and a metallic layer defining the side thereof facing the c

Abstract: A method of producing a multi-ply metal bellows wherein the plies are telescoped together to form a multi-ply tube and annular grooves are inwardly rolled in the multi-ply tube at spaced intervals therealong while the tube is supported internally on either side of the grooves, as they are rolled, and is held against substantial deformation. Crest and root constraining dies are assembled around the multi-ply tube and in the grooves and then the tube is pressurized internally, while the dies are pushed together, so that the undeformed portions of the tube bulge outwardly into the dies. The bellows is then completed by removing the dies and putting spacing shims in between the bulged convolution crest portions and then pushing the ends of the tubes until the shims are lightly held between the bulges.

Abstract: This invention is a method for manufacturing a diaphragm bellows on a continuous basis, wherein by giving a pressure to the inside of a metallic pipe having the desired diameter, the pipe is bulged in the outer circumferential direction between opposed molds which hold the pipe and, by compressing the bulged part between molds, is formed into a steep projection of the desired shape. After removing the molds the pipe is pressed from both ends thereof to form the steep projections into flat shapes to obtain the desired diaphragm bellows and the above manufacturing procedure is repeated.

Abstract: Apparatus for forming a corrugated tube from a smooth walled starting tube comprises a pair of receiving mandrels aligned spaced from each other along a preferably vertical axis and movable toward and away from each other to be engaged in opposite end portions of a starting tube. The halves of split corrugation forming discs and the halves of an end member above the uppermost of the discs, coupled together for limited movement in axial direction, are respectively carried and guided for movement in axial direction by a pair of clamping jaws tiltable between an open position permitting to align a starting tube with the mandrels and a closed position closing the split discs and the split end member and fluid tightly clamping opposite end portions of the starting tube located about said mandrels respectively between one of the mandrels and the closed end member and between the other mandrel and the clamping jaws.

Abstract: Apparatus for forming a sheet metal pulley from a cup-shaped blank in a single hydraulic forming operation. A pair of die holding members supports a plurality of groove-forming inner dies and is movably mounted on a base for horizontal reciprocal movement between open and closed die positions for capturing a pulley-forming blank therebetween. Tapered pins extend vertically through aligned openings formed in overlapping shelf members of the die holding members to wedgingly clamp the dies toward each other and to lock them in a horizontally closed position. A ram plate is mounted on a plurality of vertical posts for reciprocal vertical movement with respect to the captured blank. The ram plate has a top die which exerts axial pressure on the hub portion of the blank during the hydraulic bulging of the blank side wall by a confined fluid within the blank in cooperation with the groove-forming inner dies.

Abstract: An apparatus for manufacturing corrugated tubes comprises a unit with a hydraulic drive for clamping and sealing the tubular billet, and a device for axial compression of said tubular billet communicating with a compressed gas source. The apparatus also comprises tools installed symmetrically with relation to the direction of compression with a provision for reciprocating across said direction for at least partial encompassing of the tubular billet. The apparatus comprises a device with a pressure regulator for delivering pressurized liquid from a liquid source into the space of the tubular billet for forming the corrugated tube.

Abstract: An apparatus for manufacture of corrugated pipes by the plastic working method comprises a stand-mounted assembly for clamping and sealing a pipe blank, devised in the form of two clamps arranged coaxially at a certain distance from each other to insert the pipe blank, and furnished with a hydraulic drive. The apparatus also incorporates a device for axial compression, and tools disposed symmetrically in relation to the direction of compression and reciprocating laterally to said direction for embracing the pipe blank. The apparatus contains a device for feeding shaping fluid into the pipe blank. The hydraulic drive according to the present invention comprises hydraulic cylinders, each having a movable link provided with a through passage and mechanically coupled with the respective clamp.

Abstract: Apparatus for producing a tube with successive corrugations of different configuration from a tubular blank of uniform diameter mainly comprises a central pin having a shaft portion fixed only at one end to a stationary support and having at the other end a radially enlarged head portion cooperating with radially inwardly movable clamping and forming jaws to clamp a portion of a tubular blank therebetween. The apparatus includes further a tubular member guided on the shaft portion of the central pin and movable in axial direction by hydraulically operated members cooperating therewith.

Abstract: Apparatus for producing a tube with successive corrugations from a tubular blank of constant diameter comprises a central pin having a shaft portion fixed only at one end to a stationary support and having at the other end a radially enlarged head portion cooperating with radially inwardly moving clamping and forming jaws to clamp a portion of a tubular blank therebetween. The apparatus includes further a tubular member guided on the shaft portion of the central pin and movable in axial direction by hydraulically operated members connected thereto.

Abstract: An apparatus for the manufacture, by the hydroforming process, of expansion bellows for pipelines or the like, the apparatus being of the type comprising, for contracting longitudinally a sleeve to be formed, an actuating chamber of annular configuration defined by a rigid sleeve associated with the sleeve to be formed, a cylindrical skirt, and two sealing rings, one of which constitutes one of the supports for the sleeve to be formed. The apparatus is characterized in that the annular chamber is arranged, not outside, but inside the rigid sleeve, in such a manner that the hydroforming circuit is completely separate from the actuating circuit.

Abstract: The manufacture of hydroforming of a deformable expansion bellows. A deformable sleeve is held on a support with an inner sleeve supported inside it to define a space into which is injected liquid under pressure. An axial force is applied to the sheath with the space pressurized to produce corrugation of the sheath so as to form a bellows.

Abstract: A multiple groove pulley is formed from a cup-shaped blank by an apparatus and method in which axially displaceable segmental shaping rings are positioned at axially predetermined positions along the wall of the blank. Fluid pressure communicated to the interior of the blank expands the wall of the blank into contact with the shaping rings and at least one of the shaping rings is independently movable in an axial direction while the blank is compressed for simultaneous formation of the grooves. A sleeve member is movable axially over at least one of the shaping rings to resist radial movement of the segments while at the same time permitting full compression of the blank.

Abstract: A method and apparatus for forming contoured tubular shapes, wherein the reshaping is accomplished without substantially changing the wall thickness of the tube material such that the strength of the resultant contoured shape is not effected. Forces are applied to an area of a tube in which the contour is to be changed. The forces are controlled so as to start reformation at one portion of the area and progress axially along the tube until the desired contour in that area is formed; that is to say, there is no incremental flowing increase (decrease) of tube diameter as the tube is contoured. No shaping forces are applied to the remainder of the tube (outside the area to be contoured); the tube material is thus free to move along its longitudinal axis relative to the area being contoured. This axial movement of the material forming the wall of the tube insures that there is substantially no change in wall thickness of the tube material through the area being contoured during the contour process.

Abstract: Large diameter expanding bellows is described for pipe systems produced by the invention from portable apparatus combining fixed and slidable rings, the former connected to an end of and the latter sealably mounted on a sleeve and a skirt slideable into sealing relationship with the former and connected to the slideable ring, pressure fluid admission means communicating with the annular space between the rings and an outlet for regulation of liquid flow therefrom; a sleeve 1 may be strengthened by a core 3 of cement and fitted with a dismountable ring 4 co-operative with a displaceable ring 6 connected to an upper skirt 8 defining a chamber in communication with a pump 15 for introducing fluid in hydroforming to lower fixed ring 4.

Abstract: The rotary machine, particularly for manufacturing bellows-type articles, includes a shaping device with a rotor. The shaft of the rotor has mounted thereon a drum carrying slides, each slide being adapted to accommodate a hollow blank, to advance it into the axial bore of the respective female die and to fill the internal space of the blank with a liquid medium under pressure. The auxiliary drum likewise mounted on the rotor shaft carries male dies. A holder structure for the female dies, arranged coaxially with the male dies, is mounted on the rotor shaft intermediate the two drums. Each female die includes a plurality of closed-end sleeves received coaxially one within another, each sleeve having a bore in the bottom thereof to accommodate a blank therein and having grooves on the external surface of this bottom to form corrugations in the article being manufactured.