EP0272186B1 - Direct extrusion method at a vertical forging press, and equipment therefor - Google Patents

Description

The present invention relates to a direct spinning process particularly suitable for carrying out operations for spinning superalloy parts on a vertical forging press and it also relates to a spinning tool specially designed for the implementation of this process.

The advantages of spinning or extrusion processes for obtaining certain types of mechanical parts are well known to specialists. This kind of process is said to be direct when the part leaving the die moves in the same direction as the force applied by the punch. Special spinning presses make it possible to obtain, by this type of process, known per se, parts which are generally very long, such as tubes or various profiles for example, and in this case, during processing, the part moves in a horizontal position, at the outlet of the die. An example of this kind of process constituting the closest state of the art is illustrated by DE-C-542 045 which describes a horizontal spinning press in which the spinning pot accompanies the movement of the piece and covers the die support then remains integral with the piston during the displacement movement in the opposite direction; two stations are provided, the second spinning pot coming to cap the plot during the return. Certain parts of engines intended for aeronautical applications are also obtained by calling upon this kind of processes. This is the case, for example, of ferrules or rings of large diameter entering the fixed parts of the engine and having a profiled section which can be obtained by successive spinning, rolling and welding operations. In applications to parts of aeronautical engines, however, or to turbomachinery in general, the choice, required by the high performance (operating temperatures) and high desired characteristics (resistance, lifetime), of special materials such as nickel-based superalloys for example, requires during their implementation by spinning significant efforts which are generally inaccessible for commonly used spinning presses.

• a) sortir la table inférieure de la presse à forger verticale,
• b) sortir un lopin du four,
• c) placer ledit lopin dans le pot de filage, et une rondelle d'appui au dessus dudit lopin dans le pot de filage,
• d) rentrer la table,
• e) descendre le coulisseau supérieur de la presse de façon à ce que le poinçon pousse le lopin qui se file à travers la filière,
• f) solidariser la table supérieure de presse et le pot de filage,
• g) remonter le coulisseau supérieur de presse qui soulève à la fois le poinçon et le pot de filage,
• h) sortir la table inférieure de presse,
• i) actionner l'éjecteur inférieur de façon à soulever la pièce filée,
• j) sortir la filière et la pièce filée,
• k) ramener l'éjecteur en position de repos,
• l) rentrer la table inférieure de presse, redescendre le pot de filage en place

The invention aims to obtain by direct spinning in particular superalloy parts requiring the application of significant forces which can be achieved on vertical forging presses whose power can reach 65,000 tonnes. The invention is particularly suitable for spinning from superalloy powders. The process according to the invention which makes it possible to obtain these results without the drawbacks of the previously known processes comprises the following steps:

• a) remove the lower table from the vertical forging press,
• b) remove a piece of the oven,
• c) placing said piece in the spinning pot, and a support washer above said piece in the spinning pot,
• d) return the table,
• e) lower the upper slide of the press so that the punch pushes the piece which is spun across the die,
• f) securing the upper press table and the spinning pot,
• g) reassemble the upper press slide which lifts both the punch and the spinning pot,
• h) take out the lower press table,
• i) activate the lower ejector so as to lift the extruded part,
• j) take out the die and the extruded part,
• k) return the ejector to the rest position,
• l) retract the lower press table, lower the spinning pot into place

• g1) glisser des cales d'appui sur la face supérieure du pot de filière,
• g2) redescendre le pot de filage sur ces dites cales d'appui,
• g3) placer au moins une rondelle de surépaisseur dans le pot de filage,
• g4) redescendre le coulisseau supérieur de la presse,
• puis l'étape g) est répétée en même temps que la cale d'appui est retirée et l'opération se poursuit aux étapes h) et suivantes.

Advantageously, after step g) and before leaving the table, when an attachment of the part to the die edge is observed, the following additional steps are inserted:

• g1) slide support wedges on the upper face of the die pot,
• g2) descend the spinning pot onto these so-called support wedges,
• g3) place at least one extra thickness washer in the spinning pot,
• g4) lower the upper slide of the press,
• then step g) is repeated at the same time as the support wedge is removed and the operation continues in steps h) and following.

The tool specially designed for the implementation of the method according to the invention is characterized in that it comprises means for securing between the spinning pot and the upper press table so that the upper slide can be actuated independently or on the contrary, the spinning pot can follow the movements of said slide.

Advantageously, this tool also includes a sheath, disposed under the die and closed at its lower end so that the spun part is contained in said sheath during spinning and the ejector presses on said sheath which lifts the die when said ejector is activated.

• la figure 1 représente une demi-vue en coupe par un plan vertical passant par le centre de la table, d'une table inférieure de presse à forger verticale sur laquelle est placé un pot de filage, l'outillage étant spécialement conçu dans ce mode de réalisation conforme à l'invention pour la mise en oeuvre d'un procédé de filage direct de pièces en superalliage selon l'invention ;
• la figure 2 représente une demi-vue analogue à la figure 1, la table étant rentrée sous la presse ;
• la figure 3 représente une demi-vue analogue aux figures 1 et 2, le coulisseau supérieur de presse étant descendu ;
• la figure 4 représente une demi-vue analogue aux figures 1,2 et 3, le pot de filage étant remonté ;
• la figure 5 représente une demi-vue analogue aux figures 1,2,3 et 4, une cale d'appui étant glissée sur le pot de filière ;
• la figure 6 représente une demi-vue analogue à la figure 2 avec cale d'appui et rondelles d'épaisseur ;
• la figure 7 représente une demi-vue analogue à la figure 3 avec cale d'appui et rondelles d'épaisseur ;
• la figure 8 représente une demi-vue analogue à la figure 4 après remontée du pot de filage ;
• la figure 9 représente une demi-vue analogue à la figure 1 après actionnement de l'éjecteur ;
• la figure 10 représente une demi-vue analogue à la figure 9 après retrait de la filière et de la pièce filée.

Other characteristics and advantages of the invention will emerge more clearly from the description which follows of an embodiment of the invention, with reference to the appended drawings in which:

• Figure 1 shows a half-view in section through a vertical plane passing through the center of the table, of a lower table of vertical forging press on which is placed a spinning pot, the tooling being specially designed in this mode according to the invention for the implementation of a direct spinning process of superalloy parts according to the invention;
• 2 shows a half-view similar to Figure 1, the table being retracted under the press;
• 3 shows a half-view similar to Figures 1 and 2, the upper press slide being lowered;
• Figure 4 shows a half-view similar to Figures 1,2 and 3, the spinning pot being reassembled;
• Figure 5 shows a half-view similar to Figures 1,2,3 and 4, a support wedge being slid over the die pot;
• Figure 6 shows a half-view similar to Figure 2 with support wedge and thick washers;
• Figure 7 shows a half-view similar to Figure 3 with support wedge and thick washers;
• Figure 8 shows a half-view similar to Figure 4 after raising the spinning pot;
• Figure 9 shows a half view similar to Figure 1 after actuation of the ejector;
• Figure 10 shows a half-view similar to Figure 9 after removal of the die and the extruded part.

In Figure 1, 1 shows a movable vertical forging press table used for implementing the direct spinning process according to the invention.

On the table 1 is mounted a tool specially designed for the implementation of said process. Said tool includes a lower riser 2 fixed to the table 1 by any known means of the bolt type cooperating with slides, for example, then an intermediate wedge 3 interposed between said lower riser 2 and a pot riser 4 secured to each other by bolts 5. On said extension 4 are placed a lower outer pot 6 secured to it by bolts 7, an intermediate pot 8 of die and inside this latter a plate 9 reinforcement of the die supporting a die 10. The bore 8a of the intermediate pot 8 of the die and the cooperating external diameters, respectively 9a and 10a of the reinforcement 9 and of the die 10 are preferably conical to allow them to be lifted as will be described in more detail below. The bore 9b of the reinforcement 9 is slightly greater than that of the corresponding edge 10b of the die in order to allow the passage of the extruded part as will be described below while the die 10 has an evolving internal shape 10c adapted to the flow metal during the spinning operation. The external face 10a of the die 10 has at least two holes 11 capable of being used for handling. Above the lower outer pot 6 is placed an upper outer pot 12 which carries on its outer surface 12a at least two hooking lugs 13 pierced with a hole 14 and having a vertical slot. Above the intermediate pot 8 of the die is placed an intermediate pot 15 of spinning inside which is placed a shell 16. Inside the spinning pot is shown a piece 17 surmounted by a support washer 18. The movable table 1, the extensions 2 and 4 and wedge 3 each have, respectively, a central bore 1a, 2a, 4a and 3a and inside is arranged a tubular sheath 19, closed at its lower end by a cover of support 20. The bore 4a comprises for example a flange 4b capable of guiding the sheath 19 at its upper part and a shim 21 disposed between the bores 3a and the and the sheath 19 is also capable of serving as a guide and also serves to centering of the extension 2 relative to the table while a retaining wedge 22 integral with the sheath 19 cooperates with the bore 4a and cannot move beyond the rim 4b. In FIG. 2, 23 represents the upper slide of the press on which are mounted the elements complementary to those which have been described with reference to FIG. 2 and constituting with them said direct spinning tooling.

Said tool comprises an upper distribution table 24 secured, for example by bolts 25, with a punch holder plate 26 on which is fixed, for example by means of screws 27 a washer 28 which ensures the fixing of a punch 29 on said plate 26. The washer 28 arrives at the end of the race by pressing on the pot 15 in order to limit the stroke. The upper table 24 has at least two holes for the passage of an axis 30 for fixing a tie rod 31 the other end of which cooperates with the slot in the tab 13 and a groove 32 for the passage of a passing pin 33 in the hole 14 of the tab 13, as can be seen in FIG. 3.

Figure 5 shows a passage 6a of a bar 34 above the lower outer pot 6 for the positioning of a support wedge 35 disposed on top of the intermediate pot 8 of die. FIG. 6 shows an extra thickness washer 18a placed on the support washer 18.

Figures 1 to 10 show the successive stages of an embodiment of the direct spinning process on a vertical forging press, according to the invention.

• a) sortir la table inférieure 1 de la presse,
• b) sortir un lopin 17 du four,
• c) placer ledit lopin 17 dans le pot de filage 12 à 16 et une rondelle d'appui 18 au dessus dudit lopin 17 dans le pot de filage.

FIG. 1 represents the result at the end of steps a, b, and c consisting of:

• a) remove the lower table 1 from the press,
• b) take a piece 17 from the oven,
• c) place said piece 17 in the spinning pot 12 to 16 and a support washer 18 above said piece 17 in the spinning pot.

• d) rentrer la table 1 sous le coulisseau supérieur 23 de la presse.

Figure 2 shows the next step:

• d) return the table 1 under the upper slide 23 of the press.

• e) descendre le coulisseau supérieur 23 de façon à ce que le poinçon 29 pousse le lopin qui se file à travers la filière pour donner une pièce filée 17a
• f) Elle représente également létape suivante :
  l'extrémité inférieure du tirant 31 porté par la table supérieure 24 s'engage dans une fente de la patte d'accrochage 13 solidaire du pot de filage 12 et une goupille 33 est placée pour assurer leur solidarisation.

FIG. 3 represents the carrying out of the following direct spinning operation proper:

• e) lower the upper slide 23 so that the punch 29 pushes the piece which spins through the die to give a spun piece 17a
• f) It also represents the following stage:
  the lower end of the tie rod 31 carried by the upper table 24 engages in a slot in the hooking tab 13 secured to the spinning pot 12 and a pin 33 is placed to secure them.

• g) le coulisseau supérieur 23 de la presse est remonté, soulevant à la fois le poinçon 29 et le pot de filage 12 à 16.

Figure 4 shows the next step:

• g) the upper slide 23 of the press is raised, raising both the punch 29 and the spinning pot 12 to 16.

Figures 5,6 and 7 show an additional phase of the method which is possibly used when it is observed that the edge of the extruded part 17a remains attached to the shell 16, which would prevent translation out of under the press of the assembly lower, or that the support washer 18 remains stuck in the shell 16.

• g1) selon la figure 5, une ou plusieurs cales d'appui 35 sont glissées sur la face supérieure du pot intermédiaire 8 de filière, au moyen d'une barre de manutention 34 coopérant avec un passage 6a du pot extérieur inférieur 6,
• g2) selon la figure 6, le pot de filage 12 à 16 est redescendu sur ces dites cales d'appui et
• g3) une rondelle de surépaisseur 18a est placée dans le pot de filage 12 à 16,
• g4) selon la figure 7, le coulisseau supérieur 23 de la presse est redescendu et selon la figure 8, le coulisseau supérieur 23 est à nouveau remonté et la cale d'appui 35 est retirée, ce qui représente le même stade d'avancement du procédé que l'étape g) représentée à la figure 5.

In this case the following additional steps are added:

• g1) according to FIG. 5, one or more support wedges 35 are slid onto the upper face of the intermediate pot 8 of the die, by means of a handling bar 34 cooperating with a passage 6a of the lower outer pot 6,
• g2) according to FIG. 6, the spinning pot 12 to 16 is lowered onto these so-called support wedges and
• g3) a thickening washer 18a is placed in the spinning pot 12 to 16,
• g4) according to FIG. 7, the upper slide 23 of the press is lowered and according to FIG. 8, the upper slide 23 is again reassembled and the support wedge 35 is removed, which represents the same stage of advancement of the process as step g) shown in Figure 5.

• h) la table inférieure 1 de presse est sortie,
• i) l'éjecteur est actionné et déplace vers le haut le fourreau 19 dont l'extrémité supérieure soulève la plaque 9 renfort de filière, la filière 10 et la pièce filée 17a.

Figure 9 shows the following two steps:

• h) the lower press table 1 is out,
• i) the ejector is actuated and moves the sheath 19 upwards, the upper end of which raises the die reinforcement plate 9, the die 10 and the extruded part 17a.

• j) la filière 10 et la pièce filée 17a sont retirées de la plaque-renfort 9.

Figure 10 shows the final step of the process:

• j) the die 10 and the extruded part 17a are removed from the reinforcement plate 9.

• k) ramener l'éjecteur et le fourreau 19 en position de repos,
• l) la table inférieure 1 de presse est rentrée pour redescendre en place le pot de filage 12 à 16 .

In order to prepare the following operation to find yourself in the positions indicated in Figure 1, there are finally the steps:

• k) return the ejector and the sleeve 19 to the rest position,
• l) the lower press table 1 is retracted to lower the spinning pot 12 to 16 in place.

Claims (5)

1. Direct extrusion process notably for components in superalloys for use on high-power vertical forging presses and comprising taking the following steps:

   - a) withdraw the anvil bed (1) from the press,

   - b) withdraw a billet (17) from the furnace,

   - c) put the said billet (17) into the container (12 to 16) , with a pad (18) on top of the said billet (17) in the container,

   - d) return the anvil bed (1),

   - e) lower the crosshead (23) of the press so that the ram (29) pushes against the billet (17) which is extruded through the die (10),

   - f) couple together the upper table (24) of the press and the container (12 to 16),

   - g) raise the crosshead (23) which at the same time raises the ram (29) and the container (12 to 16),

   - h) withdraw the anvil bed (1) of the press,

   - i) actuate the lower ejector so as to raise the extruded component (17a),

   - j) remove the die (10) and the extruded component (17a),

   - k) restore the ejector to its position of rest,

   - I) return the anvil bed (1), lower the container (12 to 16) into place.
2. Direct ertrusion process in accordance with Claim 1 characterised in that the following supplementary steps are inserted after step g), before the withdrawal of the anvil bed (1):

   - g¹) slide pressure shims (35) onto the upper face of the dieholder (8),

   - g²) lower the container (12 to 16) onto the said pressure shims (35),

   - g³) place at least one over-thickness pad (18a) in the container (16),

   - g⁴) lower again the crosshead (23) of the press, then repeat the preceding step g) before passing on to step h) and the succeeding steps.
3. Tooling for carrying out a process of direct extrusion carried out on a high power vertical forging press in accordance with either of Claims 1 or 2 comprising an anvil bed (1), a container (12 to 16), a crosshead (23), a die (10), an upper table (24) and an ejector, characterised in that it comprises the means (30 to 33) of coupling together the container (12 to 16) and the upper table (24) of the press.
4. Tooling in accordance with Claim 3, characterised in that the means of coupling consist of at least two tie rods (31) each fixed to the upper table (24) by a shaft (30) and whose lower end is able to engage with a slot in a lug (13) carried on the container (12) and a groove (32) for inserting a pin (33) passing through a hole (14) in the lug (13).
5. Tooling for carrying out the direct extrusion process in accordance with either of Claims 3 or 4, characterised in that the anvil bed (1) of the press and the associated height-raising blocks (2,3,4) comprise a central bore (1a, 2a, 3a, 4a) in which is placed a tubular sleeve (19) closed at its lower end by a cover plate (20), the said sleeve (19-20) ensuring the liaison between an ejector head and a die backing ring (9) supporting the die (10) and the extruded component (17a).

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