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EP-4739449-A1 - METHOD FOR MANUFACTURING AN UPSET-FORGED PART AND ASSEMBLY FOR IMPLEMENTING THE METHOD

EP4739449A1EP 4739449 A1EP4739449 A1EP 4739449A1EP-4739449-A1

Abstract

The invention relates to a method for upset-forging a metal billet (401) intended for the manufacture of an upset-forged blank part (201) for an aircraft turbine engine guide vane. The method comprises positioning the billet (401) in an open die (403), closing the die (403) so as to compress the billet (401) between an upper part (403a) and a lower part (403b) of the die (403), thereby forming a compressed part, and upset-forging the compressed part in the closed die (403) using a punch (407) that exerts a force on the compressed part in order to form the upset-forged part (201).

Inventors

  • PEREIRA, Axel
  • BRULE, Hervé
  • FORCE, Patrick
  • DUBOST, Virgile
  • CHERY, Marine
  • BROCHARD, Marine

Assignees

  • SAFRAN AIRCRAFT ENGINES

Dates

Publication Date
20260513
Application Date
20240704

Claims (10)

  1. [1] Method (301) for manufacturing an upturned part (201), of the blank type of a rectifier arm of an aircraft turbomachine, comprising, from bottom to top along a longitudinal axis (X), a foot (201a), an aerodynamic blade (201b) and ears (201c), said method (301) being characterized in that it comprises: - positioning (303) a metal billet (401) in a die (403) in the open position, said die comprising an upper part (403a) and a lower part (403b) forming, when said die (403) is in the closed position, a cavity (405), having an opening at one end, and having substantially, in hollow, the shape of the upturned part (201); - closing (305) the die (403), so as to crush the billet (401) between the upper part (403a) and the lower part (403b) of the die (403) and to form a crushed piece (505) of which a portion (503) protrudes from the die (403) at the level of the opening of the cavity (405); and, - the upsetting (307) of the crushed part (505), in the die (403) in the closed position, by a punch (407) exerting a force on the distal end (603) of the portion (503) of said crushed part (505) which protrudes from the die (403), so as to form the upset part (201).
  2. [2] The method (301) of claim 1, wherein the die (403) is configured such that the volume of the die cavity is greater than the volume of the billet such that, upon closing, a vacuum exists between lateral edges of the crushed part (505) and said die (403).
  3. [3] Method (301) according to claim 1 or claim 2, in which the punch (407) has several flat faces whose orientation prevents the crushed part (505) from rotating on itself when the punch (407) compresses it.
  4. [4] Method (301) according to any one of the preceding claims, in which, in the part corresponding to the foot (201a) of the upturned part (201), the inclination of the walls of the cavity (405) is modified or its radius is increased in order to minimize the temperature rise of the part during the upsetting step (307).
  5. [5] Method (301) according to any one of the preceding claims, in which the dimensions and the shape of the cavity (405) of the die (403), in the part corresponding to the ears (201c) of the upturned part (201), are adapted to optimize the filling of said part of the cavity (405) of the die (403), during the upturning step (307).
  6. [6] A method (301) according to any preceding claim, wherein the volume of the cavity (405) of the die (403) is greater than the volume of the billet (401).
  7. [7] Method (301) according to any one of the preceding claims, in which, when the die (403) is in the closed position, the movement of the upper part (403a) of said die (403) is blocked by force recovery.
  8. [8] A method (301) according to any preceding claim, wherein, in the die (403), the joint plane between the lower portion (403b) and the upper portion (403a) is positioned such that once the upsetting method (301) has been carried out, when the die (403) is in the open position, the volume of the portion of the upset part (201) contained in the cavity (405) is less than the remainder of the volume of the upset part (201).
  9. [9] Method (301) according to any one of the preceding claims, in which the shape and dimensions of the cavity (405) of the die (403), in the part corresponding to the aerodynamic blade (201b) of the upturned part (201), are adapted to allow the gripping of the upturned part (201) by a clamp.
  10. [10] Assembly comprising a punch (407) and a die (403), the die comprising an upper part (403a) and a lower part (403b) forming, when said die (403) is in the closed position, a cavity (405), having an opening at one end, and having substantially, in hollow, the shape of an upturned part (201), the upturned part (201) comprising, from bottom to top along a longitudinal axis (X), a foot (201a), an aerodynamic blade (201b) and ears (201c), the punch being configured to upturn a crushed part, in the die (403) in the closed position, by exerting a force on the distal end (603) of the portion (503) of said crushed part (505) which protrudes from the die (403), so as to form the upturned part (201), the die (403) and the punch (407) being configured for implementing a method according to any one of the preceding claims.

Description

Description TITLE: METHOD FOR MANUFACTURING AN EXPELLED PART AND ASSEMBLY FOR IMPLEMENTING THE METHOD TECHNICAL AREA The invention relates to the field of forging metal parts of aircraft turbomachines. It relates in particular to a method of upsetting a metal billet and an assembly for implementing said method. PRIOR TECHNIQUE The prior art includes in particular CN-A-115846559A, EP-A1-0700738, DE- Al-3009209, CN-B-109317588, CN-U-204276771, JP-B2-6677902 and GB-A-755532. As is known, the manufacture of certain aircraft turbomachine parts, such as straightening arms, is carried out via a series of forging operations applied to a metal billet. In the particular case of forging a straightening arm, as illustrated in FIG. 1, a metal billet 101 (i.e. a metal cylinder) first undergoes upsetting to become an upset part 103, a pre-finishing step to become a pre-finished part 105 and a finishing step to become the straightening arm 107. Among these operations, upsetting involves in particular the compression of the billet, in the direction of its length, to make it take the shape of a mold (called a matrix) in which it is placed. Furthermore, in the known state of the art, the upsetting of a billet intended for the manufacture of a straightening arm comprises three distinct steps which each involve the use of a pair of different dies to successively form the three parts which make up said straightening arm, namely, its foot, its central part which is an aerodynamic blade and its upper part which is called ears because of its shape. The repression of the state of the art is therefore an operation involving complex tools and a series of equally complex manipulations. All of the operations required to produce an upturned part are therefore both time-consuming and expensive. SUMMARY OF THE INVENTION The present invention provides a solution to these drawbacks. Thus, an objective of the invention is to reduce the number and complexity of the operations required for upsetting a billet. Furthermore, the number, complexity and consequently the cost of all the forging operations required for manufacturing a part such as a straightening arm of an aircraft turbomachine are also reduced. For this purpose, the invention according to a first aspect relates to a method of manufacturing an upturned part, of the blank type of a rectifier arm of an aircraft turbomachine, comprising, from bottom to top along a longitudinal axis, a foot, an aerodynamic blade and ears, said method being characterized in that it comprises: - positioning a metal billet in a die in the open position, said die comprising an upper part and a lower part forming, when said die is in the closed position, a cavity, having an opening at one end, and having substantially, in hollow, the shape of the upturned part; - closing the die, so as to crush the billet between the upper part and the lower part of the die and to form a crushed piece, a portion of which protrudes from the die at the level of the opening of the cavity; and, - the upsetting of the crushed part, in the die in the closed position, by a punch exerting a force on the distal end of the portion of said crushed part which protrudes from the die, so as to form the upset part. The method according to the invention may comprise one or more of the following features, taken in isolation from one another or in combination with one another: - the die is configured so that the volume of the die cavity is greater than the volume of the billet so that, when it is closed, a vacuum exists between side edges of the crushed part and said die. - the punch has several flat faces whose orientation prevents the crushed part from rotating on itself when the punch compresses it. - in the part corresponding to the foot of the upturned part, the inclination of the walls of the cavity is modified or its radius is increased in order to minimize the temperature rise of the part during the upturning stage. - the dimensions and shape of the die cavity, in the part corresponding to the ears of the upturned part, are adapted to optimize the filling of said part of the die cavity, during the upturning step. - the volume of the die cavity is greater than the volume of the billet. - when the die is in the closed position, the movement of the upper part of said die is blocked by force recovery. - in the die, the parting plane between the lower part and the upper part is positioned so that once the upsetting process has been carried out, when the die is in the open position, the volume of the part of the upset part contained in the cavity is less than the rest of the volume of the upset part. - the shape and dimensions of the die cavity, in the part corresponding to the aerodynamic blade of the upturned part, are adapted to allow the upturned part to be gripped by a clamp. Furthermore, the invention according to a second aspect also relates to an assembly comprising a punch and a die, the die comprising an upper part and a lower par