EP0036365B1 - Verfahren zur Druckverformung von Werkstücken und Vorrichtung zur Durchführung dieses Verfahrens - Google Patents

Verfahren zur Druckverformung von Werkstücken und Vorrichtung zur Durchführung dieses Verfahrens Download PDF

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Publication number
EP0036365B1
EP0036365B1 EP81400387A EP81400387A EP0036365B1 EP 0036365 B1 EP0036365 B1 EP 0036365B1 EP 81400387 A EP81400387 A EP 81400387A EP 81400387 A EP81400387 A EP 81400387A EP 0036365 B1 EP0036365 B1 EP 0036365B1
Authority
EP
European Patent Office
Prior art keywords
blank
internal pressure
longitudinal compression
pressure
value
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP81400387A
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English (en)
French (fr)
Other versions
EP0036365A1 (de
Inventor
Richard Esperou
André Garnier
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vallourec SA
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Vallourec SA
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Filing date
Publication date
Application filed by Vallourec SA filed Critical Vallourec SA
Priority to AT81400387T priority Critical patent/ATE9283T1/de
Publication of EP0036365A1 publication Critical patent/EP0036365A1/de
Application granted granted Critical
Publication of EP0036365B1 publication Critical patent/EP0036365B1/de
Expired legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D26/00—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces
    • B21D26/02—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure
    • B21D26/033—Deforming tubular bodies
    • B21D26/041—Means for controlling fluid parameters, e.g. pressure or temperature
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
    • B21C37/06—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of tubes or metal hoses; Combined procedures for making tubes, e.g. for making multi-wall tubes
    • B21C37/15—Making tubes of special shape; Making tube fittings
    • B21C37/28—Making tube fittings for connecting pipes, e.g. U-pieces
    • B21C37/29—Making branched pieces, e.g. T-pieces
    • B21C37/294—Forming collars by compressing a fluid or a yieldable or resilient mass in the tube

Definitions

  • the present invention relates to a method and a device for manufacturing by hydroflambing hollow metal parts from tubular blanks or the like.
  • the present invention aims more specifically to bring improvements to the technique of hydroflambing, or hydroforming, which consists in producing the part with the desired shape in a single operation, from a blank, in a matrix of corresponding shape in associating a mechanical action obtained by the pushing of one or more pistons and a hydraulic pressure using a liquid, in particular water filling the interior of the blank.
  • the document US-A-3 350 905 describes a process for obtaining, by hydroflambing, shaped parts such as T or bulbs from blanks in the form of a section of tube or in a similar form, in which mechanical compression is applied in the longitudinal direction of the blank and then hydraulic pressure inside thereof, so as to obtain a deformation of the blank in the transverse direction.
  • the tube sections have dimensional irregularities relating to their thickness or due to ovalizations or eccentricities which are inevitable with their current manufacturing processes. These irregularities are such that the already known hydrofoaming methods are not currently satisfactory.
  • the present invention aims to provide a method and a device making it possible to avoid the above-mentioned drawbacks of previously known methods and devices and to obtain hollow metal parts having in particular constant dimensional characteristics, at rates compatible with industrial exploitation. economical by reducing manufacturing waste as much as possible, using tubular blanks obtained in particular by cutting tubes.
  • the present invention relates to a process for obtaining, by hydroflambing, shaped parts such as T or bulbs with part of blanks in the form of a section of tube or in a similar form, in which applies a mechanical compression in the longitudinal direction of the blank then a hydraulic pressure inside it, so as to obtain a deformation of the blank in the transverse direction, process characterized in that it comprises at minus a step consisting, when the longitudinal compression reaches a predetermined value, of measuring the corresponding value of the internal pressure and / or of the transverse deformation of the blank, and of determining, as a function of said corresponding value, the subsequent relationship between internal pressure and longitudinal compression.
  • the method according to the invention therefore initially allows a kind of blank test to be carried out, for example by measuring the internal pressure which must be applied to it while subjecting it to a predetermined axial compression in order to obtain a deformation. cross-section of a preset value.
  • the internal pressure that has thus been measured has a value which depends on the mechanical characteristics of the blank which, as explained above, depend on the one hand on the dimensions and in particular on the thickness or the eccentricity of the tube section and on the other hand of its qualities metallurgical.
  • This hydrofoaming curve is, in accordance with the invention, defined by the instantaneous value of the internal pressure which must be applied to the blank for each value of the longitudinal deformation of the blank due to the mechanical forces which it undergoes.
  • the present invention also relates to a device for implementing the process defined above, this device comprising a matrix capable of receiving a tubular blank or the like and means making it possible to reign inside the blank a adjustable pressure, characterized in that it further comprises a means for measuring the transverse deformations of the blank, a means for measuring the longitudinal compression of the blank, and a means for varying the internal pressure of the blank according to its longitudinal compression according to a relation determined by the value of the internal pressure and / or the transverse deformation of the blank corresponding to a predetermined value of the longitudinal compression.
  • the means for determining the longitudinal compression of the blank as well as the means for determining its transverse deformation can be constituted by rheostatic feelers which supply these quantities in electrical form.
  • the method according to the invention is in particular intended to produce single or multiple T's from sections of tube. It is also well suited for making parts having a bulb in their central part such as, for example, vehicle rear axles. However, the method according to the invention also makes it possible to produce parts having a different shape.
  • hydroflame parts weighing for example from 0.5 to 10 kilos and having a thickness of between for example 3 to 1 millimeters.
  • the time required for the hydroflambing process according to the invention can vary depending on the nature and the size of the parts, for example between ten and a few tens of seconds.
  • the characteristic process of the process according to the invention can be repeated at time intervals which are for example of the order of 2 to 4 seconds depending on the nature of the parts to be deformed.
  • the drawing shows a matrix, the lower part 1 of which is fixed and the upper part 2 of which is mounted on a movable piston 3.
  • the matrix has the general shape of a T, the blank consisting of a section of tube in front be placed from right to left between the pistons 4 and 5 of two hydraulic cylinders mounted in the chassis 6 of the device.
  • the piston 7 of a hydraulic cylinder engages in the lower branch of the T made in the matrix.
  • the piston 7 is initially pushed up against the tubular blank while remaining applied against the latter by a constant adjustable force. In this way, the piston 7 serves, so to speak, as a feeler to follow the transverse deformations of the blank during the hydroflambing process.
  • a hydraulic pump 8 controls the pistons 3 and 7 by means of the slide devices 9 and 10 which make it possible to raise and lower the mobile upper part 2 of the matrix and to allow it to move downwards by opposing a preset force.
  • the piston 7 which can also be pushed upwards at the end of the process to release the T which has just been manufactured after, of course, opening the upper part 2 of the matrix.
  • a hydraulic pump 11 supplies a pressure multiplier device with differential pistons 12, by means of an electrical control system 13, the high pressure fluid is sent by a pipe inside the blank and passing through the orifice 14 which is formed inside the piston 5.
  • a hydraulic pump 15 supplies fluid under pressure to the cylinders of the pistons 4 and 5 which provide axial compression of the blank.
  • a drawer 16 makes it possible to reverse the movement of these pistons 4 and 5.
  • a device which may for example be of the mechanical or hydraulic type, ensures that the displacements of the pistons 4 and 5 are necessarily effected symmetrically with respect to the matrix 1.
  • An electronic computer 17 is simultaneously connected to a rheostatic probe 18 which measures the displacements of the piston 7, to a rheostatic probe 19 which measures the displacements of the piston 4, to a pressure gauge 20 which measures the pressure inside the blank, to a pressure gauge 21 which measures the pressure acting on the pistons 4 and 5 and finally to the device 13 which determines the instantaneous value of the pressure inside the blank.
  • the operation of the device is as follows, starting from the position shown in the drawing, the device not containing a blank.
  • compression is applied longitudinally to the blank, the value of which is determined by the computer 17 as a function of the pressure measured by the pressure gauge 21.
  • the purpose of this longitudinal compression of the blank is to ensure sealing and subjecting the blank to longitudinal stress.
  • the piston 7 is brought upwards in contact with the blank via the drawer 10 which keeps the piston 7 applied against the blank with a constant force.
  • the electronic computer causes the progressive increase of the pressure inside the blank which results in a downward displacement of the piston 7 which is measured by the probe which transmits this information to the computer 17.
  • the computer 17 controls the device 13 which determines the pressure inside the blank so that, as a function of the displacement of the piston 4 measured by the feeler 19 la pressure prevailing inside the blank is determined according to a law previously stored in the computer 17 and which is chosen by the computer according to the value of the pressure inside the blank at moment when the piston 7 has undergone the displacement of predetermined value.
  • the hydrofoaming process then continues as a function of the law of variation of the internal pressure which has been determined by the computer 17 as a function of the criteria which have just been described. .
  • the computer 17 measures the pressure inside the blank at this instant and as a function of this pressure, again chooses the law of variation of the internal pressure of the blank according to the displacement of the piston 4 according to the value of the internal pressure of the blank at the time when the second predetermined displacement of the piston 7 was reached.
  • This process makes it possible to possibly choose a new law of internal pressure as a function of the longitudinal compression of the blank which is more appropriate than that which had been chosen initially.
  • the means for measuring the longitudinal and transverse deformations of the blank could be different from the two which have been described.
  • the choice of the law of variation of the internal pressure as a function of the longitudinal compression could also be determined as a function of the transverse deformation obtained for a given internal pressure.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Shaping Metal By Deep-Drawing, Or The Like (AREA)
  • Bending Of Plates, Rods, And Pipes (AREA)
  • Forging (AREA)
  • Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
  • Manufacture Of Electron Tubes, Discharge Lamp Vessels, Lead-In Wires, And The Like (AREA)

Claims (7)

1. Verfahren zur Druckverformung (Fließpressen) von Werkstücken mit der Form eines T oder mit einer Ausbauchung ausgehend von einem Rohling in Form eines Rohrabschnittes oder analoger Formgebung, bei dem eine mechanische Kompression in Längsrichtung des Rohlings und dann ein hydraulischer Druck im Inneren dieses Rohlings dergestalt angelegt werden, daß eine Verformung des Rohlings in Querrichtung erreicht wird, dadurch gekennzeichnet, daß das Verfahren zumindest einen Schritt aufweist, bei dem, wenn die longitudinale Kompression einen vorgegebenen Wert erreicht, der entsprechende Wert des Innendrucks und/oder der Querverformung des Rohlings gemessen werden und bei dem in Abhängigkeit von diesem entsprechenden Wert der endgültige Zusammenhang zwischen dem Innendruck und der longitudinalen Kompression bestimmt wird.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß zur Bestimmung des endgültigen Zusammenhangs zwischen dem Innendruck und der longitudinalen Kompression der Wert des Innendrucks für eine vorgegebene Querdeformation herangezogen wird.
3. Verfahren nach einem der Ansprüche 1 und 2, dadurch gekennzeichnet, daß man dem endgültigen Zusammenhang zwischen dem Innendruck und der longitudinalen Kompression auswählt aus einem Satz von von experimentell in Abhängigkeit von unterschiedlichen Arten von Rohlingen vorbestimmten Zusammenhängen.
4. Verfahren nach einem der vorangegangenen Ansprüche, dadurch gekennzeichnet, daß während der Durchführung des Fließpressens wiederholt die Bestimmung des endgültigen Zusammenhangs zwischen dem Innendruck und der longitudinalen Kompression wiederholt wird.
5. Vorrichtung zur Durchführung des Verfahrens nach einem der vorangegangenen Ansprüche mit einer Matrize (1, 2), die für die Aufnahme eines rohrförmigen oder analog geformten Rohlings ausgelegt ist und mit Mitteln (11, 12, 13), die es ermöglichen, daß im Inneren des Rohlings ein Druck mit einstellbarem Druckwert herrscht, dadurch gekennzeichnet, daß sie zusätzlich eine Einrichtung (18) zum Messen der Querverformung des Rohlings, eine Einrichtung (19) zum Messen der longitudinalen Kompression des Rohlings und eine Einrichtung (17) aufweist, die eine Änderung des Innendrucks des Rohlings in Abhängigkeit von seiner longitudinalen Kompression nach einer vorbestimmten Relation für den Wert des Innendrucks und/oder der transversalen Deformation des Rohlings, der einem vorbestimmten Wert der longitudinalen Kompression entspricht, ermöglicht.
6. Vorrichtung nach Anspruch 5, dadurch gekennzeichnet, daß die Einrichtung zur Bestimmung der longitudinalen Kompression des Rohlings durch einen rheostatischen Meßwertgeber gebildet ist.
7. Vorrichtung nach einem der Ansprüche 5 und 6, dadurch gekennzeichnet, daß die Einrichtung zur Bestimmung der transversalen Deformation . des Rohlings durch einen rheostatischen Meßwertgeber gebildet ist.
EP81400387A 1980-03-13 1981-03-13 Verfahren zur Druckverformung von Werkstücken und Vorrichtung zur Durchführung dieses Verfahrens Expired EP0036365B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT81400387T ATE9283T1 (de) 1980-03-13 1981-03-13 Verfahren zur druckverformung von werkstuecken und vorrichtung zur durchfuehrung dieses verfahrens.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8005656A FR2477918A1 (fr) 1980-03-13 1980-03-13 Procede perfectionne pour fabriquer des pieces par hydroflambage et dispositif pour la mise en oeuvre de ce procede
FR8005656 1980-03-13

Publications (2)

Publication Number Publication Date
EP0036365A1 EP0036365A1 (de) 1981-09-23
EP0036365B1 true EP0036365B1 (de) 1984-09-12

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EP81400387A Expired EP0036365B1 (de) 1980-03-13 1981-03-13 Verfahren zur Druckverformung von Werkstücken und Vorrichtung zur Durchführung dieses Verfahrens

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Country Link
EP (1) EP0036365B1 (de)
AT (1) ATE9283T1 (de)
DE (1) DE3165914D1 (de)
FR (1) FR2477918A1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4322424C1 (de) * 1993-07-06 1994-09-15 Schaefer Maschbau Wilhelm Verfahren und Vorrichtung zum Herstellen eines metallenen Hohlkörpers nach dem Innenhochdruck-Umformverfahren

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2535987B1 (fr) * 1982-11-16 1988-06-03 Vallourec Procede de formage d'un ou plusieurs bulbes, par deformation plastique en expansion de la paroi d'un troncon de tube
FR2536680B1 (fr) * 1982-11-25 1986-11-28 Sdecc Procede de fabrication d'un raccord tubulaire en forme de te
FR2654957B1 (fr) * 1989-11-30 1992-03-13 Cuq Georges Procede et dispositif pour calibrer une piece realisee par une installation d'hydroflambage.
ATA134693A (de) * 1993-07-08 1999-10-15 Elb Form Gmbh Verfahren zur innendruckgestützten umformung von metallischen hohlprofilen sowie vorrichtung zur durchführung dieses verfahrens
FR2744380B1 (fr) * 1996-02-06 1998-08-28 Bas En Basset Soc Ind De Installation pour la fabrication de pieces par hydroflambage
US5992197A (en) * 1997-03-28 1999-11-30 The Budd Company Forming technique using discrete heating zones
ES2154105B1 (es) * 1997-07-07 2001-12-01 Bas En Basset Soc Ind De Instalacion para la fabricacion de piezas por hidrodeformacion lateral.
US6006568A (en) * 1998-03-20 1999-12-28 The Budd Company Multi-piece hydroforming tool
US6128936A (en) * 1998-09-09 2000-10-10 Kabushiki Kaisha Opton Bulging device and bulging method
CN107052127B (zh) * 2017-06-12 2019-03-01 东营布鲁特新材料有限公司 一种高温气胀成形生产线系统及方法

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1048482A (fr) * 1950-09-18 1953-12-22 Ici Ltd Fabrication de raccords de tuyaux à branchements
FR2073790A5 (de) * 1969-12-17 1971-10-01 Tno

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3350905A (en) * 1963-12-21 1967-11-07 Agency Ind Science Techn Liquid pressure bulge forming apparatus

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1048482A (fr) * 1950-09-18 1953-12-22 Ici Ltd Fabrication de raccords de tuyaux à branchements
FR2073790A5 (de) * 1969-12-17 1971-10-01 Tno

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4322424C1 (de) * 1993-07-06 1994-09-15 Schaefer Maschbau Wilhelm Verfahren und Vorrichtung zum Herstellen eines metallenen Hohlkörpers nach dem Innenhochdruck-Umformverfahren

Also Published As

Publication number Publication date
EP0036365A1 (de) 1981-09-23
FR2477918A1 (fr) 1981-09-18
ATE9283T1 (de) 1984-09-15
FR2477918B1 (de) 1984-03-02
DE3165914D1 (en) 1984-10-18

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