EP0331539A1 - Method of making forged blanks from bar material by upsetting, in particular for compressor blades, and tooling equipment for carrying out the method - Google Patents

Method of making forged blanks from bar material by upsetting, in particular for compressor blades, and tooling equipment for carrying out the method Download PDF

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Publication number
EP0331539A1
EP0331539A1 EP89400273A EP89400273A EP0331539A1 EP 0331539 A1 EP0331539 A1 EP 0331539A1 EP 89400273 A EP89400273 A EP 89400273A EP 89400273 A EP89400273 A EP 89400273A EP 0331539 A1 EP0331539 A1 EP 0331539A1
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EP
European Patent Office
Prior art keywords
container
section
bar
upsetting
cross
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Granted
Application number
EP89400273A
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German (de)
French (fr)
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EP0331539B1 (en
Inventor
Alain Georges Henri Lorieux
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Safran Aircraft Engines SAS
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Societe Nationale dEtude et de Construction de Moteurs dAviation SNECMA
SNECMA SAS
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J5/00—Methods for forging, hammering, or pressing; Special equipment or accessories therefor
    • B21J5/06—Methods for forging, hammering, or pressing; Special equipment or accessories therefor for performing particular operations
    • B21J5/08—Upsetting
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J5/00—Methods for forging, hammering, or pressing; Special equipment or accessories therefor
    • B21J5/008—Incremental forging
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21K—MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
    • B21K3/00—Making engine or like machine parts not covered by sub-groups of B21K1/00; Making propellers or the like
    • B21K3/04—Making engine or like machine parts not covered by sub-groups of B21K1/00; Making propellers or the like blades, e.g. for turbines; Upsetting of blade roots

Definitions

  • the present invention relates to a process for the production of blanks forged in bar by upsetting as well as a tool intended for the implementation of said process. It also relates to a turbomachine compressor blade, the manufacturing of which involves the application of said upsetting process.
  • Figures 1a, 1b, 1c, 1d of the accompanying drawings illustrate the production of a delivery on a bar B, placed in a container A, during which during four successive operations corresponding respectively to the four figures, a reduction in length l1, l2, l3 and l4 is obtained and the phenomena which have just been reported (buckling then twisting) appear leading to the defects which have been noted (folds and disturbed fiber drawing).
  • the process for manufacturing blanks forged in bar by upsetting which makes it possible to avoid these drawbacks is characterized in that it comprises at least two successive stages: (a) a first upsetting step during which, at least from a first deformation stage, contact is maintained between at least three generatrices of said bar portion and the interior surface of a first container which comprises, between two of said contact lines respectively, a longitudinal hollow outgrowth forming in cross section a lobed part, a second upsetting step during which, at least from a first deformation stage, contact is maintained between the crown generators of the longitudinal protrusions obtained on the first blank at the end of the first step (a) and the inner surface of a second container having an enveloping section of said first blank.
  • the first container has a cruciform section cavity, the cylindrical bar being in contact with the interior surface of the container along four generatrices located at 90 ° from one another and the second container has a square section cavity , with rounded corners, the tops of the protuberances or lobes of the cruciform section of the bar obtained at the end of the first step being in contact respectively with one side of said square.
  • the bar is held in support at least along three generators, thus avoiding any deformation by buckling, while the flow of the alloy can only take place in the direction hollow parts of the container, thus making any torsional deformation impossible.
  • the contact maintained between the end generators of the blank and the walls of the container prevents any deformation by buckling or twisting.
  • the process for manufacturing blanks forged by upsetting according to the invention applies in particular to bar products such as a cylindrical bar 1 shown in its initial form in FIGS. 2a and 2b.
  • the bar 1 is placed in a first container 2 secured to a forging press or machine delivery of a type known per se which is not shown in more detail in the drawings.
  • a forging press or machine delivery of a type known per se which is not shown in more detail in the drawings.
  • this first pushing step (a) one end 1a of the bar 1 is subjected to the pushing action of a punch 3 moved by the pushing and control means of said machine.
  • the portion 1b of the bar 1 subjected to the upsetting thus tends to occupy the available volume of the container 2 limited by the face of the punch 3, which leads to a reduction in length of said portion 1b, accompanied by an increase in the corresponding cross section. .
  • FIGS. 1-10 In the embodiment of the invention shown in FIGS.
  • the first container 2 used during the first step of the upsetting process comprises a cavity 4 which has in cross section a generally cruciform shape composed of four lobed parts 4a, 4b, 4c, 4d arranged symmetrically in pairs, thus providing four generators 5a, 5b, 5c, 5d located at 90 ° from one another, which cooperate with four corresponding generatrices of the repressed portion 1b of the bar 1 by maintaining, from a first deformation stage, permanent contact with them during the repression step .
  • Said contact according to the generators between container and bar becomes necessary from the moment when, during the upsetting operation, there are risks of creating irreversible defects by buckling or twisting. Contact can be made from the start of the operation.
  • the intermediate blank 1c obtained at the end of the first step (a) is placed in a second container 6, as shown diagrammatically in FIGS. 4a and 4b, and its end is again subjected to the pushing action of a punch 7.
  • the second container 6 has a cavity 8 which has in cross section a generally square shape, with rounded corners.
  • Intermediate draft 1c has a cruciform section which reproduces the shape of the cavity 4 of the first container 2 and the generators 1d, 1e, 1f and 1g corresponding to the vertices of the lobed parts of this cruciform section of the intermediate blank 1c are placed in contact with lines of corresponding support of the sides of the cavity square of the second container 6 and in a similar manner to the first step (a), during the second pushing step (b), the contact is also maintained permanently, from a first deformation stage, at the level of these four symmetrical generators two by two, between the external surface of the blank 1c and the surface of the cavity 8 of the second container 6.
  • a variable radial clearance from 0 to 0.5 mm in the present application, can be provided at the start of the second stage between the cooperating generators of the bar and of the container.
  • the initial upsetting portion 1b has a final section 1d of forged blank as shown in FIG. 5 in the embodiment which comes from 'be described.
  • This repressed portion of bar 1b may in particular be intended to constitute the base of a turbomachine blade obtained by forging.
  • 7a, 7b, 7c respectively represent, in a schematic section, other usable forms of container cavity 9a, 9b, 9c, respectively associated with a portion of bar to be pushed back from section 10a, 10b, 10c, 10c, 10d.
  • This bar section at the start is of a shape adapted to the final part to be obtained and, in addition to being cylindrical, can in particular be rectangular or square.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Forging (AREA)

Abstract

The upsetting method comprises at least two successive steps during which, at least after a first deformation stage, during the first step a contact is maintained between at least three generatrices (5a, 5b, 5c, 5d) of the bar (1b) to be upset and the inside surface of a first container (2) which comprises, between two of the said lines of contact respectively, a hollow longitudinal excrescence forming, in cross section, a lobed section (4a, 4b, 4c, 4d) and, during the second step, a contact is maintained between the apex generatrices (1d, 1e, 1f, 1g) of the longitudinal excrescences of the blank (1c) obtained in the first step and the inside surface of a second container (6). <IMAGE>

Description

La présente invention concerne un procédé de fabrication d'ébauches forgées en barre par refoulage ainsi qu'un outillage destiné à la mise en oeuvre dudit procédé. Elle concerne également une aube de compresseur de turbomachine dont la fabrication comporte l'application dudit procédé de refoulage.The present invention relates to a process for the production of blanks forged in bar by upsetting as well as a tool intended for the implementation of said process. It also relates to a turbomachine compressor blade, the manufacturing of which involves the application of said upsetting process.

Il est courant dans la fabrication de certaines pièces telles que des aubes de compresseur à partir d'ébauches forgées d'effectuer une opération de refoulage de l'extrémité d'une barre cylindrique afin d'obtenir par augmentation de la section le volume de matière necessaire, par exemple, à la réalisation du pied dans le cas d'une aube.It is common in the manufacture of certain parts such as compressor blades from forged blanks to carry out a pressing operation of the end of a cylindrical bar in order to obtain by increasing the section the volume of material. necessary, for example, for the realization of the foot in the case of a dawn.

Dans les données de définition d'une telle opération de refoulage, on peut retenir deux types de paramètres :
- des paramètres technologiques tel que le taux de refoulage t, défini par :
t = (Lo - Ll)/Do
où Lo est la longueur initiale de la portion de barre à refouler,
Ll est la longueur de cette même portion après refoulage,
Do est le diamètre initial de la barre à refouler ;
Lo - Ll représente la course utile du poinçon de la machine de forgeage utilisée et la limite supérieure de cette course est une donnée de construction de ladite machine ;
- des paramètres métallurgiques et notamment le rapport de réduction η défini par :
r = Lo/Ll = Sl/So = (Dl/Do)²
où So est la section transversale initiale de la barre,
Sl est la section transversale de la barre après refoulage et Dl est le diamètre correspondant.In the data for defining such a pumping operation, two types of parameters can be retained:
- technological parameters such as the delivery rate t, defined by:
t = (Lo - Ll) / Do
where Lo is the initial length of the portion of bar to be driven back,
Ll is the length of this same portion after upsetting,
Do is the initial diameter of the bar to be driven;
Lo - Ll represents the useful stroke of the punch of the forging machine used and the upper limit of this stroke is a data of construction of said machine;
- metallurgical parameters and in particular the reduction ratio η defined by:
r = Lo / Ll = Sl / So = (Dl / Do) ²
where So is the initial cross section of the bar,
Sl is the cross section of the bar after upsetting and Dl is the corresponding diameter.

Dans les diverses applications connues du procédé de refoulage, il apparaît que pour éviter des défauts inac­ceptables sur les ébauches obtenues, le procédé est soumis à des limitations géométriques. Ces défauts dus à une maîtrise insuffisante de la déformation au cours de l'opération consistent notamment en replis qui peuvent être dus à un phénomène de flambage de la portion de barre à refouler ou en un fibrage perturbé, dû à un phénomène de torsion de la barre après flambage.In the various known applications of the upsetting process, it appears that to avoid unacceptable defects on the blanks obtained, the process is subject to geometric limitations. These defects due to insufficient control of the deformation during the operation consist in particular of folds which may be due to a phenomenon of buckling of the portion of bar to be driven back or to a disturbed fiber drawing, due to a phenomenon of torsion of the bar after buckling.

Les figures 1a, 1b, 1c, 1d des dessins joints en annexe illustrent la réalisation d'un refoulage sur une barre B, placée dans un conteneur A, au cours duquel lors de quatre opérations successives correspondant respectivement aux quatre figures, une réduction de longueur l₁, l₂, l₃ et l₄ est obtenue et les phénomènes qui viennent d'être signalés (flambage puis torsion) apparaissent conduisant aux défauts qui ont été notés (replis et fibrage perturbé).Figures 1a, 1b, 1c, 1d of the accompanying drawings illustrate the production of a delivery on a bar B, placed in a container A, during which during four successive operations corresponding respectively to the four figures, a reduction in length l₁, l₂, l₃ and l₄ is obtained and the phenomena which have just been reported (buckling then twisting) appear leading to the defects which have been noted (folds and disturbed fiber drawing).

Il est couramment admis que pour éviter ces défauts, une valeur limite supérieure du taux de refoulage t de 4 lorsque le refoulage est effectué en une opération ou de 6 lorsqu'il est effectué en deux opérations successives doit être respectée. Une limitation du rapport Dl/Do de 1,5 à 2 suivant le type d'alliage concerné est également fixée quelquefois.It is commonly accepted that to avoid these defects, an upper limit value of the delivery rate t of 4 when the delivery is carried out in one operation or of 6 when it is carried out in two successive operations must be respected. A limitation of the Dl / Do ratio of 1.5 to 2 depending on the type of alloy concerned is also sometimes set.

Diverses tentatives d'amélioration ont recherché à dépasser les limitations géométriques imposées jusqu'à présént sans encourir l'apparition des défauts. On a ainsi tenté d'effectuer l'opération de refoulage au moyen d'un outillage animé d'un mouvement de nutation sur l'extrémité à refouler de la barre, celle-ci étant simul­tanément déplacée vers la zone de travail d'une longueur correspondant au volume à déformer. On a également tenté d'effectuer un refoulage en plusieurs passes en avançant successivement, à chaque passe, la barre d'une longueur correspondant au volume à déformer. Des exemples de telles réalisations sont donnés par FR-A-2050 483, FR-A-2050 484, et par FR-A-2220 328. Dans ces procédés, les résultats n'ont pas été entièrement satisfaisants et notamment une orientation suffisamment régulière du fibrage ne peut pas être assurée.Various attempts at improvement have sought to exceed the geometrical limitations imposed until now without incurring the appearance of defects. An attempt was thus made to carry out the pushing operation using a tool animated by a nutation movement on the end to be pushed back of the bar, the latter being simultaneously moved towards the working area of a length corresponding to the volume to be deformed. An attempt has also been made to push back in several passes by advancing successively, with each pass, the bar of a length corresponding to the volume to be deformed. Examples of such embodiments are given by FR-A-2050 483, FR-A-2050 484, and by FR-A-2220 328. In these methods, the results have not been entirely satisfactory and in particular a sufficiently regular orientation fiberizing cannot be guaranteed.

Le procédé de fabrication d'ébauches forgées en barre par refoulage permettant d'éviter ces inconvénients est caractérisé en ce qu'il comporte au moins deux étapes successives :
- (a) une première étape de refoulage durant laquelle, au moins à partir d'un premier stade de déformation, un contact est maintenu entre au moins trois génératrices de ladite portion de barre et la surface intérieure d'un pre­mier conteneur qui comporte, entre deux desdites lignes de contact respectivement, une excroissance en creux longitu­dinale formant en section transversale une partie lobée,
- une deuxième étape de refoulage durant laquelle, au moins à partir d'un premier stade de déformation, un contact est maintenu entre les génératrices de sommet des excroissances longitudinales obtenues sur la première ébauche à l'issue de la première étape (a) et la surface intérieure d'un deuxième conteneur présentant une section enveloppante de ladite première ébauche.The process for manufacturing blanks forged in bar by upsetting which makes it possible to avoid these drawbacks is characterized in that it comprises at least two successive stages:
(a) a first upsetting step during which, at least from a first deformation stage, contact is maintained between at least three generatrices of said bar portion and the interior surface of a first container which comprises, between two of said contact lines respectively, a longitudinal hollow outgrowth forming in cross section a lobed part,
a second upsetting step during which, at least from a first deformation stage, contact is maintained between the crown generators of the longitudinal protrusions obtained on the first blank at the end of the first step (a) and the inner surface of a second container having an enveloping section of said first blank.

Avantageusement, le premier conteneur présente une cavité de section cruciforme, la barre cylindrique étant en contact avec la surface intérieure du conteneur le long de quatre génératrices situées à 90° l'une de l'autre et le deuxième conteneur présente une cavité de section carrée, à coins arrondis, les sommets des excroissances ou lobes de la section cruciforme de la barre obtenue à l'issue de la première étape étant en contact respectivement avec un côté dudit carré.Advantageously, the first container has a cruciform section cavity, the cylindrical bar being in contact with the interior surface of the container along four generatrices located at 90 ° from one another and the second container has a square section cavity , with rounded corners, the tops of the protuberances or lobes of the cruciform section of the bar obtained at the end of the first step being in contact respectively with one side of said square.

Dans certaines applications concernant des alliages de titane, des taux de refoulage de 8 à 10 obtenus en deux opérations par le procédé conforme à l'invention néces­sitaient par les procédés antérieurs connus auparavant au minimum cinq opérations successives. Selon les critères de qualité imposés et selon les applications, notamment en fonction des alliages utilisés, des taux de refoulage su­périeurs peuvent être obtenus et dans tous les cas, supé­rieurs aux résultats antérieurs. En outre, les examens métallographiques effectués sur les ébauches forgées obtenues par le procédé de refoulage selon l'invention ont montré une nette amélioration de l'orientation du fibrage par rapport à ces procédés antérieurs ainsi qu'une absence totale de défauts. Ces résultats améliorés proviennent directement de l'application du procédé selon l'invention et peuvent s'expliquer par ses caractéristiques. En effet, lors de la première étape du procédé, la barre est mainte­nue en appui au moins suivant trois génératrices, évitant ainsi toute déformation par flambage, alors que l'écou­lement de l'alliage ne peut se faire qu'en direction des parties en creux du conteneur, rendant ainsi toute déformation par torsion impossible. De même, lors de la deuxième étape, le contact maintenu entre les génératrices extrêmes de l'ébauche et les parois du conteneur empêche toute déformation par flambage ou par torsion.In certain applications relating to titanium alloys, discharge rates of 8 to 10 obtained in two operations by the process according to the invention required by the prior processes previously known at least five successive operations. According to the quality criteria imposed and according to the applications, in particular according to the alloys used, higher pumping rates can be obtained and in all cases, higher than the previous results. In addition, metallographic examinations carried out on the forged blanks obtained by the upsetting process according to the invention have shown a marked improvement in the orientation of the fiber drawing compared to these previous processes as well as a total absence of defects. These improved results come directly from the application of the method according to the invention and can be explained by its characteristics. In fact, during the first step of the process, the bar is held in support at least along three generators, thus avoiding any deformation by buckling, while the flow of the alloy can only take place in the direction hollow parts of the container, thus making any torsional deformation impossible. Likewise, during the second step, the contact maintained between the end generators of the blank and the walls of the container prevents any deformation by buckling or twisting.

D'autres caractéristiques et avantages de l'invention seront mieux compris à la lecture de la description qui va suivre d'un mode de réalisation de l'invention, en référence aux dessins annexés sur lesquels :

  • - les figures 1a, 1b, 1c, 1d qui ont été précédemment décrites représentent schématiquement les déformations d'une barre lors d'opérations successives de refoulage n'appliquant pas l'invention :
  • - les figures 2a, 2b représentent la barre dans sa forme initiale avant refoulage, respectivement en vue de face et en vue selon une section transversale,
  • - les figures 3a, 3b représentent schématiquement la barre représentée aux figures 2a, 2b au cours de la première étape de l'opération de refoulage selon le procédé conforme à l'invention, respectivement en vue suivant une coupe longitudinale et selon une section transversale ;
  • - les figures 4a, 4b représentent schématiquement l'ébauche obtenue à l'issue de la première étape, au cours de la deuxième étape de l'opération de refoulage selon le procédé conforme à l'invention, respectivement, selon des vues analogues aux figures 3a et 3b, suivant une coupe longitudinale et selon une section transversale ;
  • - la figure 5 représente une vue de l'ébauche forgée finale obtenue par le procédé conforme à l'invention, selon une section transversale ;
  • - la figure 6 représente selon une vue analogue à la figure 4b, en section transversale, une variante de mise en oeuvre de la deuxième étape du procédé conforme à l'invention :
  • - les figures 7a, 7b, 7c montrent des variantes de mise en oeuvre d'étapes du procédé de refoulage conforme à l'invention
Other characteristics and advantages of the invention will be better understood on reading the description which follows of an embodiment of the invention, with reference to the appended drawings in which:
  • FIGS. 1a, 1b, 1c, 1d which have been previously described schematically represent the deformations of a bar during successive upsetting operations not applying the invention:
  • FIGS. 2a, 2b show the bar in its initial form before upsetting, respectively in front view and in view in a cross section,
  • - Figures 3a, 3b schematically represent the bar shown in Figures 2a, 2b during the first step of the upsetting operation according to the method according to the invention, respectively in view in a longitudinal section and in a cross section;
  • - Figures 4a, 4b schematically show the blank obtained at the end of the first step, during the second step of the upsetting operation according to the method according to the invention, respectively, according to views similar to the figures 3a and 3b, along a longitudinal section and along a cross section;
  • - Figure 5 shows a view of the final forged blank obtained by the method according to the invention, in a cross section;
  • FIG. 6 represents, in a view similar to FIG. 4b, in cross section, an alternative implementation of the second step of the method according to the invention:
  • - Figures 7a, 7b, 7c show alternative embodiments of steps of the upsetting process according to the invention

Le procédé de fabrication d'ébauches forgées par refoulage conforme à l'invention s'applique notamment à des produits en barre tels que une barre cylindrique 1 représentée dans sa forme initiale aux figures 2a et 2b. Comme représenté schématiquement sur les figures 3a et 3b, pour la réalisation de la première étape (a) du procédé de refoulage conforme à l'invention, la barre 1 est placée dans un premier conteneur 2 solidaire d'une presse à forger ou machine à refouler d'un type connu en soi qui n'est pas représentée plus en détails sur les dessins. Au cours de cette première étape (a) de refoulage, une extrémité 1a de la barre 1 est soumise à l'action de refoulement d'un poinçon 3 mû par les moyens de poussée et de commande de ladite machine. La portion 1b de la barre 1 soumise au refoulage tend ainsi à occuper le volume disponible du conteneur 2 limité par la face du poinçon 3, ce qui entraîne une diminution de longueur de ladite portion 1b, accompagnée d'une augmentation de la section transversale correspondante. Dans le mode de réalisation de l'invention représenté sur les figures 3a et 3b, le premier conteneur 2 utilisé lors de la première étape du procédé de refoulage comporte une cavité 4 qui présente en section transversale une forme générale cruciforme composée de quatre parties lobées 4a, 4b, 4c, 4d disposées symétriquement deux à deux, ménageant ainsi quatre génératrices 5a, 5b, 5c, 5d situées à 90° l'une de l'autre, qui coopèrent avec quatre génératrices correspondantes de la portion refoulée 1b de la barre 1 en maintenant, à partir d'un premier stade de déformation, un contact permanent avec elles au cours de l'étape de refoulage. Ledit contact suivant les génératrices entre conteneur et barre devient nécessaire à partir du moment où au cours de l'opération de refoulage apparaissent des risques de création de défauts irréversibles par flambage ou torsion. Le contact peut être réalisé dès le début de l'opération. Il est souvent dans la pratique plus aisé, pour des facilités de mise en oeuvre, de prévoir un jeu radial au départ entre lesdites génératrices qui peut aller dans le présent mode de réalisation jusqu'à 0,5mm. L'action, dans le sens de l'effort appliqué et du déplacement obtenu, du poinçon 3 s'exerce suivant la flèche F tandis que les flèches f symbolisent les directions d'écoulement de l'alliage constituant la barre 1 au cours du refoulage.The process for manufacturing blanks forged by upsetting according to the invention applies in particular to bar products such as a cylindrical bar 1 shown in its initial form in FIGS. 2a and 2b. As shown diagrammatically in FIGS. 3a and 3b, for carrying out the first step (a) of the upsetting process according to the invention, the bar 1 is placed in a first container 2 secured to a forging press or machine delivery of a type known per se which is not shown in more detail in the drawings. During this first pushing step (a), one end 1a of the bar 1 is subjected to the pushing action of a punch 3 moved by the pushing and control means of said machine. The portion 1b of the bar 1 subjected to the upsetting thus tends to occupy the available volume of the container 2 limited by the face of the punch 3, which leads to a reduction in length of said portion 1b, accompanied by an increase in the corresponding cross section. . In the embodiment of the invention shown in FIGS. 3a and 3b, the first container 2 used during the first step of the upsetting process comprises a cavity 4 which has in cross section a generally cruciform shape composed of four lobed parts 4a, 4b, 4c, 4d arranged symmetrically in pairs, thus providing four generators 5a, 5b, 5c, 5d located at 90 ° from one another, which cooperate with four corresponding generatrices of the repressed portion 1b of the bar 1 by maintaining, from a first deformation stage, permanent contact with them during the repression step . Said contact according to the generators between container and bar becomes necessary from the moment when, during the upsetting operation, there are risks of creating irreversible defects by buckling or twisting. Contact can be made from the start of the operation. It is often in practice easier, for ease of implementation, to provide a radial clearance at the start between said generators which can go in the present embodiment up to 0.5 mm. The action, in the direction of the force applied and of the displacement obtained, of the punch 3 is exerted according to the arrow F while the arrows f symbolize the directions of flow of the alloy constituting the bar 1 during the upsetting .

Pour la deuxième étape (b) du procédé de refoulage conforme à l'invention dont le déroulement est similaire à celui de la première étape (a) qui vient d'être décrit ci-dessus, l'ébauche intermédiaire 1c obtenue à l'issue de la première étape (a) est placée dans un deuxième conteneur 6, comme représenté schématiquement sur les figures 4a et 4b, et son extrémité est à nouveau soumise à une action de refoulement d'un poinçon 7. Dans le mode de réalisation de l'invention représenté aux figures 4a et 4b, le deuxième conteneur 6 comporte une cavité 8 qui présente en section transversale une forme générale carrée, à coins arrondis. L'ébauche intermédiaire 1c présente une section cruciforme qui reproduit la forme de la cavité 4 du premier conteneur 2 et les génératrices 1d, 1e, 1f et 1g correspondant aux sommets des parties lobées de cette section cruciforme de l'ébauche intermédiaire 1c sont placées au contact de lignes d'appui correspondantes des côtés du carré de cavité du deuxième conteneur 6 et de manière similaire à la première étape (a), au cours de la deuxième étape (b) de refoulage, le contact est également maintenu en permanence, à partir d'un premier stade de déformation, au niveau de ces quatre génératrices symétriques deux à deux, entre la surface externe de l'ébauche 1c et la surface de la cavité 8 du deuxième conteneur 6. Comme précédemment, un jeu radial variable, de 0 à 0,5 mm dans la présente application, peut être ménagé au départ de la deuxième étape entre les génératrices coopérantes de la barre et du conteneur.For the second step (b) of the upsetting process according to the invention, the progress of which is similar to that of the first step (a) which has just been described above, the intermediate blank 1c obtained at the end of the first step (a) is placed in a second container 6, as shown diagrammatically in FIGS. 4a and 4b, and its end is again subjected to the pushing action of a punch 7. In the embodiment of the Invention shown in Figures 4a and 4b, the second container 6 has a cavity 8 which has in cross section a generally square shape, with rounded corners. Intermediate draft 1c has a cruciform section which reproduces the shape of the cavity 4 of the first container 2 and the generators 1d, 1e, 1f and 1g corresponding to the vertices of the lobed parts of this cruciform section of the intermediate blank 1c are placed in contact with lines of corresponding support of the sides of the cavity square of the second container 6 and in a similar manner to the first step (a), during the second pushing step (b), the contact is also maintained permanently, from a first deformation stage, at the level of these four symmetrical generators two by two, between the external surface of the blank 1c and the surface of the cavity 8 of the second container 6. As before, a variable radial clearance, from 0 to 0.5 mm in the present application, can be provided at the start of the second stage between the cooperating generators of the bar and of the container.

A l'issue de cette deuxième étape (b) du procédé de refoulage conforme à l'invention, la portion refoulée initiale 1b présente une section finale 1d d'ébauche forgée telle que représentée à la figure 5 dans le mode de réalisation qui vient d'être décrit. Cette portion refoulée de barre 1b peut notamment être destinée à constituer le pied d'une aube de turbomachine obtenue par forgeage.At the end of this second step (b) of the upsetting process according to the invention, the initial upsetting portion 1b has a final section 1d of forged blank as shown in FIG. 5 in the embodiment which comes from 'be described. This repressed portion of bar 1b may in particular be intended to constitute the base of a turbomachine blade obtained by forging.

Divers modes de réalisation appliquant les caractéristi­ques du procédé de refoulage conforme à l'invention qui ont été décrites peuvent être envisagées. Notamment, en fonction de la nature des alliages concernés, des pièces dont la fabrication est envisagée, du taux de refoulage recherché, un nombre différent d'étapes du procédé de re­foulage peut être appliqué. Différentes formes de cavité du conteneur utilisé, ou suivant les étapes associées, peuvent également être associées à condition de ménager, conformément à l'invention, un contact permanent au cours d'une étape entre plusieurs génératrices de l'ébauche et de la surface de cavité du conteneur. Le deuxième conte­neur 6 utilisé lors de la deuxième étape (b) de refoulage dans le mode de réalisation qui a été décrit et dont la section est représentée à la figure 4b peut, par exemple, comporter une cavité 8a délimitée par une surface qui est représentée par une section circulaire à la figure 6. Les figures 7a, 7b, 7c, représentent respectivement, selon une section schématique, d'autres formes utilisables de cavité de conteneur 9a, 9b, 9c, respectivement associé à une portion de barre à refouler de section 10a,10b,10c, 10c, 10d. Cette section de barre au départ est de forme adaptée à la pièce finale à obtenir et outre cylindrique peut notamment être rectangulaire ou carrée.Various embodiments applying the characteristics of the upsetting process according to the invention which have been described can be envisaged. In particular, depending on the nature of the alloys concerned, parts whose manufacture is envisaged, the desired upsetting rate, a different number of steps in the upsetting process can be applied. Different forms of cavity of the container used, or according to the associated steps, can also be associated provided that, in accordance with the invention, permanent contact is made during a step between several generators of the blank and of the container cavity surface. The second container 6 used during the second delivery step (b) in the embodiment which has been described and the section of which is shown in FIG. 4b may, for example, include a cavity 8a delimited by a surface which is shown by a circular section in FIG. 6. FIGS. 7a, 7b, 7c respectively represent, in a schematic section, other usable forms of container cavity 9a, 9b, 9c, respectively associated with a portion of bar to be pushed back from section 10a, 10b, 10c, 10c, 10d. This bar section at the start is of a shape adapted to the final part to be obtained and, in addition to being cylindrical, can in particular be rectangular or square.

Claims (9)

1. Procédé de fabrication d'ébauches forgées en barre par refoulage dans lequel au moins une portion de barre, de longueur initiale Lo et de section initiale So de diamètre Do, est tranformée par refoulage en une portion de barre de longueur finale Ll et de section finale Sl de diamètre Dl telles que Lo > Ll, So < Sl, Do > Dl, un paramètre technologique t ou taux de refoulage étant représenté par t =(Lo - Ll)/Do, ladite barre placée dans un outillage de support ou conteneur étant soumise à l'action de refoulement d'un poinçon d'une presse de forgeage, s'exerçant sur l'extrémité de la barre caractérisé en ce qu'il comporte au moins deux étapes successives : - (a) une première étape de refoulage durant laquelle,au moins à partir d'un premier stade de déformation, un contact est maintenu entre au moins trois génératrices de ladite portion de barre et la surface intérieure d'un premier conteneur qui comporte, entre deux desdites lignes de contact respec-tivement, une excroissance en creux longitudinale formant en section transversale une partie lobée ; - (b) une deuxième étape de refoulage durant laquelle,au moins à partir d'un premier stade de déformation, un contact est maintenu entre les génératrices de sommet des excroissances longitudinales obtenues sur la première ébauche à l'issue de la première étape (a) et la surface intérieure d'un deuxième conteneur présentant une section enveloppante de ladite première ébauche. 1. A method of manufacturing blanks forged into bars by upsetting in which at least one portion of bars, of initial length Lo and of initial section So of diameter Do, is transformed by upsetting into a portion of bars of final length Ll and final section Sl of diameter Dl such as Lo> Ll, So <Sl, Do> Dl, a technological parameter t or delivery rate being represented by t = (Lo - Ll) / Do, said bar placed in a support tool or container being subjected to the pushing action of a punch from a forging press, acting on the end of the bar, characterized in that it comprises at least two successive stages: (a) a first upsetting step during which, at least from a first deformation stage, contact is maintained between at least three generatrices of said bar portion and the interior surface of a first container which comprises, between two of said contact lines respectively, a longitudinal hollow outgrowth forming in cross section a lobed part; - (b) a second upsetting step during which, at least from a first deformation stage, contact is maintained between the crown generators of the longitudinal protrusions obtained on the first blank at the end of the first step ( a) and the inner surface of a second container having an enveloping section of said first blank. 2. Procédé de fabrication d'ébauches forgées en barre par refoulage selon la revendication 1 dans lequel lors de la première étape (a), le premier conteneur présente en section transversale un contour intérieur de forme générale cruciforme et la première ébauche refoulée est maintenue au cours de ladite première étape (a) suivant quatre génératrices longitudinales périphériquement réparties à 90° l'une de l'autre et présente à l'issue de la première étape (a) quatre excroissances longitudinales orientées à 90° l'une de l'autre.2. A method of manufacturing blanks forged by pushing back according to claim 1 wherein during the first step (a), the first container has in cross section an interior contour of generally cruciform shape and the first repressed blank is maintained at during said first step (a) along four longitudinal generatrices peripherally distributed at 90 ° from one another and presents at the end of the first step (a) four longitudinal protrusions oriented at 90 ° from one other. 3. Procédé de fabrication d'ébauches forgées en barre par refoulage selon l'une des revendications 1 ou 2 dans lequel lors de la deuxième étape (b), le deuxième conteneur présente en section transversale un contour intérieur de forme générale carrée, à coins arrondis.3. A method of manufacturing blanks forged in bar by upsetting according to one of claims 1 or 2 wherein in the second step (b), the second container has in cross section an inner contour of generally square shape, with corners rounded. 4. Procédé de fabrication d'ébauches forgées en barre par refoulage selon l'une des revendications 1 ou 2 dans lequel lors de la deuxième étape (b), le deuxième conteneur présente en section transversale un contour intérieur circulaire.4. Method for manufacturing blanks forged in bar by upsetting according to one of claims 1 or 2 wherein in the second step (b), the second container has in cross section a circular interior contour. 5. Outillage destinés à la mise en oeuvre du procédé de fabrication d'ébauches forgées en barre par refoulage selon l'une quelconque des revendications 1 à 4 consistant en deux conteneurs comportant chacun une cavité dans laquelle est placée ladite ébauche caractérisés en ce que le premier conteneur adapté pour la réalisation de la première étape (a) dudit procédé présente une géométrie de surface intérieure de cavité telle que l'ébauche avant forgeage est en contact au moins à partir d'un premier stade de déformation, au moins suivant trois génératrices avec des génératrices coopérantes du conteneur et telle que des excroissances longitudinales en creux sont ménagées entre lesdites génératrices et en ce que le deuxième conteneur adapté pour la réalisation de la deuxième étape (b) dudit procédé présenne une géometrie de surface intérieure de cavité telle que le contour de section transversale enveloppe le contour de section transversale du premier conteneur.5. Tools intended for the implementation of the process for manufacturing blanks forged in bar by upsetting according to any one of claims 1 to 4 consisting of two containers each comprising a cavity in which is placed said blank characterized in that the first container suitable for carrying out the first step (a) of said method has a geometry of internal cavity surface such that the blank before forging is in contact at least from a first deformation stage, at least along three generatrices with cooperating generators of the container and such that recessed longitudinal protuberances are formed between said generators and in that the second container suitable for carrying out the second step (b) of said method presents a geometry of the interior surface of the cavity such that the cross-section contour surrounds the cross-section contour of the first container. 6. Outillages destinés à la mise en oeuvre du procédé de fabrication d'ébauches forgées en barre par refoulage selon la revendication 5 caractérisé en ce que ledit premier conteneur comporte une cavité présentant une section transversale cruciforme à quatre lobes répartis à 90° l'un de l'autre.6. Tools for the implementation of the process for manufacturing blanks forged in bar by upsetting according to claim 5 characterized in that said first container comprises a cavity having a cruciform cross section with four lobes distributed at 90 ° one the other. 7. Outillages destinés à la mise en oeuvre du procédé de fabrication d'ébauches forgées en barre par refoulage selon l'une des revendications 5 ou 6 caractérisés en ce que ledit deuxième conteneur comporte une cavité présentant une section transversale de forme générale carrée, à coins arrondis, la longueur d'un côté du carré représentant la distance entre deux sommets d'excroissances diamétralement opposées du premier conteneur.7. Tools intended for the implementation of the process for manufacturing blanks forged in bar by upsetting according to one of claims 5 or 6 characterized in that said second container comprises a cavity having a cross section of generally square shape, rounded corners, the length of one side of the square representing the distance between two vertically opposite peaks of the first container. 8. Outillages destinés à la mise en oeuvre du procédé de fabrication d'ébauches forgées en barre par refoulage selon l'une des revendications 5 ou 6 caractérisés en ce que ledit deuxième conteneur comporte une cavité présentant une section transversale circulaire, dont la circonférence enveloppe la section de cavité du premier conteneur.8. Tools intended for the implementation of the process for manufacturing blanks forged in bar by upsetting according to one of claims 5 or 6 characterized in that said second container comprises a cavity having a circular cross section, the envelope circumference of which the cavity section of the first container. 9. Aube de compresseur de turbomachine caractérisée en ce qu'elle est obtenue par un procédé de fabrication qui comporte une opération de refoulage de l'extrémité de barre correspondant au pied de l'aube, réalisée suivant un procédé conforme à l'une des revendications 1 à 4.9. Dawn of a turbomachine compressor, characterized in that it is obtained by a manufacturing process which includes a pushing operation of the bar end corresponding to the foot of the blade, produced according to a process in accordance with one of the claims 1 to 4.
EP89400273A 1988-02-03 1989-02-01 Method of making forged blanks from bar material by upsetting, in particular for compressor blades, and tooling equipment for carrying out the method Expired - Lifetime EP0331539B1 (en)

Applications Claiming Priority (2)

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FR8801227A FR2626507A1 (en) 1988-02-03 1988-02-03 METHOD OF MANUFACTURING BLANK FORGED BLANKS, IN PARTICULAR FOR COMPRESSOR BLADES AND IMPLEMENTATION TOOLS
FR8801227 1988-02-03

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EP0331539A1 true EP0331539A1 (en) 1989-09-06
EP0331539B1 EP0331539B1 (en) 1994-01-26

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EP (1) EP0331539B1 (en)
JP (1) JPH0732945B2 (en)
CA (1) CA1330172C (en)
DE (1) DE68912620T2 (en)
FR (1) FR2626507A1 (en)
IL (1) IL89160A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2695578A1 (en) * 1992-09-17 1994-03-18 Snecma Surface working tool for forging shaped bar-type workpieces - comprises cylindrical sleeve with longitudinal cavity, with internal channels receiving movable components varying cavity cross=section
EP0786296A1 (en) * 1996-01-29 1997-07-30 CDP Aluminiumtechnik GmbH &amp; Co. KG Method and device for the production of semi-finished products
EP3260216A4 (en) * 2015-02-18 2018-10-03 Nippon Steel & Sumitomo Metal Corporation Metal pipe having thickened end portion, and method of manufacturing same

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU6343290A (en) * 1989-09-29 1991-04-28 Motorola, Inc. Flat panel display using field emission devices
US5007873A (en) * 1990-02-09 1991-04-16 Motorola, Inc. Non-planar field emission device having an emitter formed with a substantially normal vapor deposition process
US5030921A (en) * 1990-02-09 1991-07-09 Motorola, Inc. Cascaded cold cathode field emission devices
US5230134A (en) * 1992-02-11 1993-07-27 Laue Charles E Method of making a petal rod
US5606790A (en) * 1993-04-09 1997-03-04 Charles E. Laue Method of making a two piece pedal rod
US5425286A (en) * 1993-04-09 1995-06-20 Laue; Charles E. Two piece pedal rod and method of making same
JP3680421B2 (en) * 1996-06-04 2005-08-10 トヨタ自動車株式会社 Method for forging bar work
US6193821B1 (en) 1998-08-19 2001-02-27 Tosoh Smd, Inc. Fine grain tantalum sputtering target and fabrication process
DE10035224A1 (en) * 2000-07-20 2002-01-31 Man Turbomasch Ag Ghh Borsig Process and blank for producing rhomboid blades for axial turbomachines
US7213436B2 (en) * 2004-05-28 2007-05-08 Shape Corporation Stamping apparatus for forming rod with configured ends
FR2874339B1 (en) * 2004-08-23 2008-12-05 Snecma Moteurs Sa METHOD FOR MANUFACTURING CONSTITUENT PIECES OF A HOLLOW DRAW BY DRILLING ON PRESS
EP1927413B1 (en) * 2006-12-01 2009-08-19 Topy Kogyo Kabushiki Kaisha Press forging method
JP4301525B2 (en) * 2006-12-01 2009-07-22 トピー工業株式会社 Compression forging method
GB201707896D0 (en) * 2017-05-17 2017-06-28 Rolls Royce Plc Forging apparatus and method

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2220328A1 (en) * 1973-03-07 1974-10-04 Inst Obrobki Plastycznes
SU804163A1 (en) * 1979-04-13 1981-02-15 Горьковский Конструкторско-Технологическийинститут Холодновысадочного И Пружинногопроизводства Tool for preliminary upsetting of multiface cross-section articles
SU821016A1 (en) * 1979-06-08 1981-04-15 Предприятие П/Я Г-4585 Method of upsetting tubes
FR2494606A1 (en) * 1980-11-21 1982-05-28 Honda Motor Co Ltd ELECTRICAL DISCHARGE METHOD AND DEVICE FOR CARRYING OUT SAID METHOD

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3154849A (en) * 1961-01-18 1964-11-03 Thompson Ramo Wooldridge Inc Metal forging process
US3392569A (en) * 1966-02-03 1968-07-16 Columbus Auto Parts Insulator pin
SE371045B (en) * 1969-07-03 1974-11-04 Varta Ag
FR2050483B1 (en) * 1969-07-03 1974-12-20 Massey B Et S Ltd
GB1282759A (en) * 1969-08-18 1972-07-26 Maurice Lachaussee Method of manufacturing discs from wire
JPS61193739A (en) * 1985-02-21 1986-08-28 Toyota Motor Corp Upsetting forming method

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2220328A1 (en) * 1973-03-07 1974-10-04 Inst Obrobki Plastycznes
SU804163A1 (en) * 1979-04-13 1981-02-15 Горьковский Конструкторско-Технологическийинститут Холодновысадочного И Пружинногопроизводства Tool for preliminary upsetting of multiface cross-section articles
SU821016A1 (en) * 1979-06-08 1981-04-15 Предприятие П/Я Г-4585 Method of upsetting tubes
FR2494606A1 (en) * 1980-11-21 1982-05-28 Honda Motor Co Ltd ELECTRICAL DISCHARGE METHOD AND DEVICE FOR CARRYING OUT SAID METHOD

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN, vol. 11, no. 21 (M-555)[2468], 21 janvier 1987; & JP-A-61 193 739 (TOYOTA MOTOR CORP.) 28-08-1986 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2695578A1 (en) * 1992-09-17 1994-03-18 Snecma Surface working tool for forging shaped bar-type workpieces - comprises cylindrical sleeve with longitudinal cavity, with internal channels receiving movable components varying cavity cross=section
EP0786296A1 (en) * 1996-01-29 1997-07-30 CDP Aluminiumtechnik GmbH &amp; Co. KG Method and device for the production of semi-finished products
EP3260216A4 (en) * 2015-02-18 2018-10-03 Nippon Steel & Sumitomo Metal Corporation Metal pipe having thickened end portion, and method of manufacturing same
US10514113B2 (en) 2015-02-18 2019-12-24 Nippon Steel Corporation Metal pipe having thickened end portion, and method of manufacturing same

Also Published As

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DE68912620T2 (en) 1994-05-19
FR2626507B1 (en) 1994-04-22
DE68912620D1 (en) 1994-03-10
FR2626507A1 (en) 1989-08-04
IL89160A (en) 1992-08-18
EP0331539B1 (en) 1994-01-26
US4970887A (en) 1990-11-20
IL89160A0 (en) 1989-09-10
CA1330172C (en) 1994-06-14
JPH0732945B2 (en) 1995-04-12
JPH01237039A (en) 1989-09-21

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