Technical field of the invention

The present invention relates in particular to a tool for removing a single fan disc from a module and to a method for removing a single fan disc from a module by means of such a tool.

Technical background

A turbomachine, such as a turbofan engine, comprises, upstream to downstream in the direction of gas flow, a fan, one or more compressor stages (low pressure then high pressure), a combustion chamber, a or several turbine stages (high pressure then low pressure) and an exhaust nozzle.

Such a turbomachine corresponds to the assembly of a plurality of modules mounted relative to each other. During a maintenance action, different modules are dismantled and transported to different stations in order to undergo various maintenance operations (replacement of wearing parts, replacement/repair of parts with defects, etc.) necessary for the delivery in service of the turbomachine.

In the remainder of the description, more particular attention will be paid to the “low pressure compressor module” hereinafter referred to as the “module”.

Such a module is defined along a longitudinal axis X and comprises a rotor and a stator independent of each other.

The rotor comprises in particular a fan disc, a drum and an annular sealing part centered on the X axis and fixed to each other via a circular row of bolts each comprising a screw and a nut. Each screw also passes through a retaining member arranged at

inside the rotor. Each retaining member has at least two facing lugs arranged around a head of the screw and projecting relative thereto, this retaining member making it possible to hold the head of the corresponding screw in place when the screw is removed. associated nut which is located outside the rotor. The rotor also comprises several annular rows of vanes attached to the drum and arranged one behind the other, each row of vanes being more commonly referred to as a “moving wheel”.

The stator is centered on the X axis and surrounds the drum. The stator comprises several annular rectifiers interposed between the moving wheels. The first rectifier is associated with the fan so as to form stage No. 1, the following ones each being associated with a movable wheel so as to form the following stages. Each rectifier comprises an inner shroud and an outer shroud connected to one another by an annular row of vanes. The outer shrouds of all the rectifiers are clamped to each other.

The existing tools make it possible to dismantle the module as a whole according to a determined method in which the fan disk is one of the elements of the module deposited last. In other words, the removal of the fan disc cannot be done without carrying out a complete dismantling of the module.

There is an increasing demand for maintenance operations relating solely to the fan disk, these maintenance operations requiring only the removal of the fan disk.

It is understood that the existing tools are not suitable in the case where it is necessary to remove only the fan disc. Indeed, as mentioned above, for such an operation, the operators are obliged to carry out a complete dismantling of the module, to the detriment of course of productivity.

The objective of the present invention is thus to propose, on the one hand, a tool for removing a single fan disc from a module and, on the other hand, a method for removing a single fan disc from a module by means of of such a tool, thus allowing a gain in productivity.

Summary of the invention

The invention thus proposes a tool for removing a fan disc alone from a module with longitudinal axis X of a turbomachine comprising a rotor and a stator, the rotor comprising the fan disc, a drum and a sealing part ring centered on the X axis and fixed to each other via a circular row of bolts each comprising a screw and a nut, each screw passing through a retainer arranged inside the rotor, each retainer having at least two opposite lugs arranged around a head of the screw and projecting relative to the head, the stator being centered on the X axis and surrounding the drum, the stator being longitudinally delimited by a rectifier arranged opposite the disk fan, the stator comprising an outer ring having a flange,the Z vertical axis tool comprising:

- A frame comprising ground support means;

- an annular plate centered on the Z axis and integral with the frame, this plate comprising first and second circular rows of pins as well as two holes arranged around the Z axis following a regular pitch, each of the two holes being arranged between the first and second rows, each of the pins being configured to support the head of a screw so as not to damage the lugs of the retaining members, each hole being configured to receive an indexing finger of the module relative to the tool ;

- at least three supports distributed evenly around the Z axis and integral with the frame, each support comprising a support surface, the support surfaces being coplanar and being configured to support the flange of the rectifier of the module, the three supports being located vertically below the top;

- A first visual cue disposed on the frame and configured to angularly orient the module with respect to the tool.

Such a tool makes it possible to remove the fan disk alone while retaining the rest of the assembled module. Thus, during a maintenance operation relating solely to the fan disk, such a tool allows a significant gain in productivity.

In addition, such a tool makes it possible to remove the fan disk alone without damaging the other components of the module, and in particular the retainers and the screws.

Such a tool can also be used for refitting the repaired fan disc (or fitting a new fan disc) onto the rest of the assembled module.

The tool according to the invention may comprise one or more of the following characteristics and/or steps, taken separately from each other or in combination with each other:

- the first visual cue is in the form of a vertical line;

- the tool comprises a second visual cue arranged on the frame and configured to determine a vertical position of the module from which the module must be indexed relative to the tool;

- the second visual cue is in the form of a horizontal line;

- each of the three supports comprises a recess configured to allow the passage of an annular row of blades attached to the drum.

The present invention also relates to a method for removing a single fan disc from a module with longitudinal axis X of a turbomachine comprising a rotor and a stator, the rotor comprising the fan disc, a drum and a spare part. annular seal centered on the X axis and fixed to each other via a circular row of bolts each comprising a screw and a nut, each screw passing through a retaining member arranged inside the rotor, each retaining member having at the at least two facing lugs disposed around a head of the screw and projecting relative to the head, the stator being centered on the axis X and surrounding the drum, the stator being longitudinally delimited by a rectifier disposed opposite of the fan disc, the rectifier comprising an outer shroud having a flange,using the tool as described above, the method chronologically comprising the steps consisting in:

a) remove two predetermined bolts hereinafter referred to as reference bolts so as to have two free holes at the level of the rotor, the angular difference between the reference bolts being equal to the angular difference between the two holes of the plate;

b) positioning the module above the tool in a vertical position so that the longitudinal axis X of the module is substantially vertical and substantially coaxial with the vertical axis Z of the tool, the fan disc then being vertically drum top;

c) aligning one of the free orifices with the first visual cue so as to orient the module angularly with respect to the tool;

d) indexing the module with respect to the tool by introducing two indexing fingers from outside the module, each indexing finger passing through a free hole in the rotor then a hole in the plate;

e) resting the heads of the screws on the pins of the plate, the drum then surrounding the plate;

f) rest the rectifier flange on the bearing surfaces of the three supports;

g) remove all the nuts from the bolts;

h) extracting the fan disk alone in a controlled manner via at least one extractor;

i) remove the fan disc alone.

Such a method makes it possible to remove the fan disk alone, by means of the tool, while retaining the rest of the assembled module. Thus, during a maintenance operation relating solely to the fan disk, the implementation of such a method allows a significant gain in productivity.

In addition, such a method makes it possible to remove the fan disk alone without damaging the other components of the module, and in particular the retainers and the screws.

The method according to the invention may comprise one or more of the following characteristics and/or steps, taken separately from each other or in combination with each other:

- the fan disc is extracted during step h) via three extractors evenly distributed around the Z axis, the extraction being controlled by progressively unscrewing three extraction nuts previously screwed onto three screws each located nearby one of the three extractors, and gradually inserting shims around the three screws provided with extraction nuts between the fan disc and the drum, the extraction nuts and the shims being in a non-metallic material;

- step h) comprises the sub-steps consisting of:

h1) placing each extraction nut at a distance D from an upper face of a corresponding lobe of the fan disk, the upper face being placed facing the extraction nut;

h2) operate the three extractors so that each upper face is in contact with the corresponding extraction nut;

h3) placing one or more shims having a total height H around each screw provided with an extraction nut between the fan disc and the drum, the total height H being equal to the distance D;

- step d) is carried out when the flange of the rectifier is located vertically at the level of a second visual marker arranged on the frame of the tool;

- the module is held during steps a) to f) via a first handling tool on which the module is positioned and held, the first handling tool comprising at least a pair of first opposed pins, each of the first pins being linked to a bracket for a lifting system;

- The first manipulation tool is configured to make it possible to adjust longitudinally over a predetermined range the positioning of the rotor vis-à-vis the stator or vice versa;

- the fan disc is held during steps g) to i) via a second handling tool on which the fan disc is positioned and held, the second handling tool comprising at least a pair of second opposed journals, each of the second trunnions being linked to an attachment bracket of a lifting system.

Brief description of figures

The invention will be better understood and other details, characteristics and advantages of the invention will appear more clearly on reading the following description given by way of non-limiting example and with reference to the appended drawings in which:

[Fig.1] Figure 1 is a cutaway perspective view illustrating the module in a second state E2;

[Fig.2] Figure 2 is an axial half-section view illustrating the module in a first state E1;

[Fig.3] Figure 3 is a detail view of Figure 2 illustrating in particular the assembly of a fan disc, a drum and an annular sealing part via bolts;

[Fig.4] Figure 4 is a perspective view of a tool for removing the fan disk of the module illustrated in Figures 1 to 3;

[Fig.5] Figure 5 is a detail view of Figure 4;

[Fig.6] Figure 6 is a perspective view of the module positioned in a horizontal position as part of a method of removing a fan disc from a module illustrated in Figures 1 to 3 by means of a tool illustrated in Figures 4 and 5;

[Fig.7] la figure 7 est une vue en perspective illustrant une étape consistant à retirer deux boulons de référence de manière à disposer de deux orifices libres ;

[Fig.8] la figure 8 est une vue de détail de la figure 7 illustrant un orifice libre ;

[Fig.9] la figure 9 est une vue en perspective illustrant une étape consistant à aligner un des orifices libres avec un premier repère visuel de l’outil ;

[Fig.10] la figure 10 est une vue en perspective illustrant une étape consistant à indexer le module par rapport à l’outil ;

[Fig.1 1 ] la figure 1 1 est une vue en demi-coupe axiale illustrant une étape consistant à mettre en appui des têtes de vis sur des pions d’un plateau de l’outil ;

[Fig.12] la figure 12 est une vue en perspective illustrant une étape consistant à mettre en appui une bride d’un redresseur du module sur des surface d’appui de supports ;

[Fig.13] la figure 13 est une vue en perspective illustrant une étape consistant à extraire de manière contrôlée le disque de soufflante ;

[Fig.14] la figure 14 est une vue de détail de la figure 13 ;

[Fig.15] la figure 15 est une vue en perspective illustrant une sous-étape consistant à disposer des écrous d’extraction sur des vis ;

[Fig.16] la figure 16 est une vue en perspective illustrant une sous-étape consistant à actionner des extracteurs ;

[Fig.17] la figure 17 est une vue en perspective illustrant une sous-étape consistant à intercaler une ou plusieurs cales ;

[Fig.18] Figure 18 is a perspective view illustrating a step of depositing the fan disk alone.

Detailed description of the invention

In Figures 1 and 2 is shown a module 1 (low pressure compressor module) of a turbomachine defined along a longitudinal axis X and comprising a rotor 2 and a stator 3 independent of each other, and in other words the rotor 2 and stator 3 are not guided relative to each other via, for example, a bearing. The longitudinal axis X of module 1 is

coinciding with the longitudinal axis of the turbomachine, when the module 1 is in place in the turbomachine.

In the present application, the terms "internal" and "external" associated with the various components of the module 1 are defined with respect to the longitudinal axis X.

More precisely, the rotor 2 comprises a fan disc 4, a drum 5 and an annular sealing piece 6 centered on the X axis and fixed to each other via a circular row of bolts 7 each comprising a screw 8 and a nut 9. Each screw 8 passes through a retaining member 10 arranged inside the rotor 2. Each retaining member 10 has at least two facing lugs 11 arranged around a head 12 of the screw 8 and projecting from relative to the head 12.

The stator 3 is centered on the axis X and surrounds the drum 5. The stator 3 is longitudinally delimited by a rectifier r4 arranged opposite the fan disc 4, the rectifier r4 comprising an outer shroud 14 having a flange 15.

According to the embodiment illustrated in the figures and in particular in Figures 1 to 3, the fan disc 4 is arranged upstream of the drum 5 and comprises a plurality of cells each intended to receive a fan blade (not included in the module 1 ). The fan disc 4 has a plurality of lobes 16 distributed in a regular manner around the axis X at its downstream end, these lobes 16 forming a flange. The fan disc 4 is partially shown in Figure 2. The head 12 of each screw 8 is arranged inside the rotor 2. The nut 9 of each bolt 7 is arranged outside the rotor 2. Each screw 8 successively crosses, from the head 12 to the corresponding nut 9, a through hole made in the corresponding retaining member 10,

As illustrated in Figure 3, each retaining member 10 is arranged longitudinally between the head 12 of the corresponding screw 8 and the sealing part 6. Each retaining member 10 comprises four lugs 1 1 facing two by two which surround the head 12 of the corresponding screw 8, the lugs 11 projecting relative to the head 12. The retainers 10 and the heads 12 of the screws 8 are arranged in a common circular groove 17 of the sealing part 6 A retaining member 10 keeps the head 12 of the corresponding screw 8 (located inside the rotor 2) in place when the associated nut 9 (located outside the rotor 2) is removed.The sealing part 6 is also fitted onto a projection 18 of the fan disk 4 at its internal end and hooked onto a projection 19 of the drum 5 at its external end.

As illustrated in FIG. 2, rotor 2 also comprises four annular rows of blades 20 attached to drum 5 and arranged one behind the other, each row of blades 20 being more commonly referred to as a “moving wheel”. The four mobile wheels are respectively numbered, from upstream to downstream, wheel R2 (for wheel n°2) to wheel R5 (for wheel n°5), wheel R1 (for wheel n°1) being considered as the fan .

According to the embodiment illustrated in the figures and in particular in FIG. 2, the stator 3 comprises five annular rectifiers interposed between the moving wheels. The five rectifiers are numbered, from upstream to downstream, rectifier r1 (for rectifier n°1) to rectifier r5 (for rectifier n°5). The first rectifier r1 is associated with the fan so as to form stage n°1, the following ones being each associated with a wheel (wheels R2 to R5) so as to form the following stages (stage n°2 to stage n° 5). Each rectifier r1 to r5 comprises an inner shroud 13 and an outer shroud 14 connected to one another by an annular row of vanes 21. The vanes 21 are for example welded to the inner and outer shrouds 13, 14 so as to form a machine-welded assembly.

By convention, in the present application, the terms “upstream” and “downstream” are defined with respect to the direction of circulation of the gases in the module 1, the gases successively passing through the various stages.

FIG. 2 illustrates module 1 in a first state E1 corresponding to module 1 as it is when it is received to undergo a maintenance operation.

FIG. 1 illustrates the module 1 in a second state E2 in which the fifth rectifier r5 has been removed, the outer shroud 14 of the fourth rectifier r4 then having a free flange 15. The second state E2 here corresponds to the state in which find module 1 to remove fan disc 4 alone.

A module 1 found in a third state E3 corresponds to a module 1 found in a second state E2 from which the fan disk 4 has been removed.

The fan disc 4 alone is removed (or removed) from a module 1 which is in a second state E2 by means of a tool 22.

According to the invention, the tool 22 is defined along a vertical axis Z and comprises:

- A frame 23 comprising ground support means 24;

- an annular plate 25 centered on the Z axis and integral with the frame 23, this plate 25 comprising first and second circular rows 26a, 26b of pins 27 as well as two holes 28 arranged around the Z axis in a regular pitch, each of the two holes 28 being arranged between the first and second rows 26a, 26b, each of the pins 27 being configured to support the head 12 of a screw 8 so as not to damage the lugs 11 of the retaining members 10, each hole 28 being configured to receive an indexing pin 29 of the module 1 with respect to the tool 22;

- au moins trois supports 30 répartis de manière régulière autour de l’axe Z et solidaires du bâti 23, chaque support 30 comprenant une surface d’appui 31 , les surfaces d’appui 31 étant coplanaires et étant configurées pour supporter la bride 15 du redresseur r4 du module 1 , les trois supports 30 étant verticalement situés au-dessous du plateau 25 ;

- un premier repère visuel 32 disposé sur le bâti 23 et configuré pour orienter angulairement le module 1 par rapport à l’outil 22.

Dans la présente demande, les termes « inférieur » et « supérieur » associés aux différents composants de l’outil 22 sont définis par rapport à l’axe vertical Z. En outre, dans la présente demande, les termes « interne » et « externe » associés aux différents composants de l’outil 22 sont définis par rapport à l’axe vertical Z.

Selon le mode de réalisation illustré sur les figures et notamment les figures 4 et 5, le bâti 23 comprend une plateforme 33 sur laquelle repose les supports 30 et un fût 34 sur lequel repose le plateau 25. La plateforme 33 est plane, perpendiculaire à l’axe Z et sensiblement triangulaire, chaque support 30 étant disposé au niveau d’une portion angulaire saillante de la plateforme 33. Le fût 34 est centré sur l’axe Z et s’élève depuis la plateforme 33. Les moyens d’appui au sol 24 comprennent ici trois pieds répartis de manière régulière autour de l’axe Z.

Le plateau 25 comprend une surface supérieure 35 annulaire délimitée par deux rebords 36, ces rebords 36 étant configurés pour maintenir les extrémités de la pièce d’étanchéité 6 lors de l’emmanchement du disque de soufflante réparé (ou d’un nouveau disque de soufflante) sur un module 1 se trouvant dans un troisième état E3. Les pions 27 des première et seconde rangées 26a, 26b sont disposés sur la surface supérieure 35. Les première et seconde rangées 26a, 26b possèdent le même nombre de pions 27 (ici dix pions) et sont symétriques par rapport à l’axe Z. Les trous 28 sont ainsi également symétriques par rapport à l’axe Z. Les pions 27 ainsi que les deux trous 28 sont disposés à équidistance de l’axe Z. Les trous 28 sont ici des trous borgnes découchant au niveau de la surface supérieure 35. L’écart angulaire entre les deux trous 28 est égal à 180 degrés. Les doigts d’indexage 29 ont été représentés sur la figure 5 afin d’indiquer la localisation des trous 28. Le plateau 25 comprend une protection thermique 37 au niveau de sa surface interne, de manière à

protéger le plateau 25 de la chaleur lors de l’emmanchement du disque de soufflante réparé (ou d’un nouveau disque de soufflante). En effet, pour réaliser l’emmanchement, la pièce d’étanchéité 6 est chauffée à une température prédéterminée.

Les surfaces d’appui 31 se trouvent dans un même plan perpendiculaire à l’axe Z. Chaque surface d’appui 31 se situe à une extrémité supérieure du support correspondant 30. Chaque surface d’appui 31 se présente sous la forme d’un secteur annulaire et est délimitée extérieurement par une bordure 38. Les trois supports sont 30 disposés par rapport aux pions 27 de sorte que les têtes 12 prennent appui avant la bride 15 lors de la mise en position du module 1 sur l’outil 22. Chaque support 30 comprend un évidement 39 orienté du côté de l’axe vertical Z et configuré pour permettre le passage de la cinquième roue R5, lors de la mise en position du module 1 sur l’outil 22. Les supports 30 peuvent être réglables par rapport à la plateforme 33 suivant une direction perpendiculaire à l’axe Z.

Le premier repère visuel 32 se présente sous la forme d’une ligne verticale 32 disposée sur la périphérie du fût 34 et la périphérie du plateau 25, cette ligne verticale 32 étant configurée pour orienter angulairement le module 1 par rapport à l’outil 22. Ce premier repère visuel 32 peut être obtenu via l’application d’une ou plusieurs bandes autocollantes.

L’outil 22 comprend un second repère visuel 40 qui se présente sous la forme d’une ligne horizontale 40 disposée sur la périphérie du fût 34, cette ligne horizontale 40 étant configurée pour déterminer une position verticale du module 1 à partir de laquelle le module 1 doit être indexé par rapport à l’outil 22. La ligne horizontale croise ici la ligne verticale. De la même manière que le premier repère visuel 32, ce second repère visuel 40 peut être obtenu via l’application d’une ou plusieurs bandes autocollantes.

Avantageusement, le plateau 25 et les supports 30 sont réalisés dans un matériau non métallique, de manière à ne pas endommager le module 1. Le plateau 25 et les supports 30 sont par exemple réalisés en téflon®.

The removal (or removal) of a fan disc 4 alone from a module 1 located in a second state E2, by means of the tool 22, is carried out according to a method comprising chronologically the steps consisting in: a ) remove two predetermined bolts 7 hereinafter referred to as reference bolts so as to have two free holes 41 at the level of the rotor 2, the angular difference between the reference bolts being equal to the angular difference between the two holes 28 of the plate 25; (Figures 6 to 8)

b) positioning the module 1 above the tool 22 in a vertical position so that the longitudinal axis X of the module 1 is substantially vertical and substantially coaxial with the vertical axis Z of the tool 22, the fan disk 4 then being vertically above the drum 5;

c) aligning one of the free orifices 41 with the first visual cue 32 so as to orient the module 1 angularly with respect to the tool 22; (Figure 9)

d) indexing the module 1 with respect to the tool 22 by introducing from outside the module 1 two indexing fingers 29, each indexing finger 29 passing through a free orifice 41 of the rotor 2 then a hole 28 of the plate 25 ; (Figure 10)

e) resting the heads 12 of the screws 8 on the pins 27 of the plate 25, the drum 5 then surrounding the plate 25; (Figure 1 1 )

f) resting the flange 15 of the rectifier r4 on the bearing surfaces 31 of the supports 30; (Figure 12)

g) remove all the nuts 9 from the bolts 7;

h) extracting the fan disk 4 alone in a controlled manner via at least one extractor 42; (Figures 13 to 17)

i) remove the fan disc 4 alone. (Figure 18)

As mentioned above, the method is implemented on a module 1 which is in a second state E2, and in other words a module 1 from which the fifth rectifier r5 has been removed.

The module 1 is held during steps a) to f) via a first handling tool 43 on which the module 1 is positioned and held, the

first handling tool 43 comprising at least one pair of first opposed journals 44, 45, each of the first journals 44, 45 being linked to an attachment bracket 46 of a lifting system 47.

According to the embodiment illustrated in the figures and in particular in Figures 6 to 12, the first manipulation tool 43 comprises a first part 48 able to be fixed to the rotor 2 of the module 1 and a second part 49 able to be fixed to the stator 3 of the module 1. The first manipulation tool 43 comprises adjustment means configured to adjust longitudinally over a predetermined range the positioning of the first part 48 (rotor 2) vis-à-vis the second part 49 (stator 3) or vice versa . As mentioned above, rotor 2 and stator 3 are independent of each other. This longitudinal adjustment is used in particular to ensure that the heads 12 of the screws 8 bear before the flange 15 when the module 1 is positioned on the tool 22.

Advantageously, as illustrated in Figures 6 to 8, during step a), the module 1 is in a horizontal position so that the longitudinal axis X of the module 1 is substantially parallel to the ground on which the tool rests. 22. The first handling tool 43 is linked to a first lifting system 47 via the middle pins 44 and to a second lifting system 47 via the end pins 45.

As illustrated in FIGS. 6 to 8, during step a), an operator removes the bolts 7 placed at 3 o'clock and 9 o'clock by analogy with the dial of a clock. The bolts 7 placed at 3 o'clock and 9 o'clock are thus considered to be the reference bolts. The angular difference between the two reference bolts is indeed equal to the angular difference between the two holes 28 of the plate 25, namely 180 degrees. At the end of step a), the free orifices 41 are then at 3 o'clock and 9 o'clock.

As illustrated in FIGS. 9 to 12, during steps b) to f), the module 1 is in the vertical position, the fan disc 4 then being vertically above the drum 5. The first manipulation tool 43 is linked to a single lifting system 47 via the end pins 45.

As illustrated in FIG. 9, during step c), an operator checks the first manipulation tool 43 so as to align one of the free orifices 41 (identifiable via the absence of the nut) with the vertical line (first visual cue 32). This step c) aligns the two free holes 41 with the two holes 28 of the plate 25.

As illustrated in Figure 10, step d) is performed when the free flange 15 of the rectifier r4 is located vertically at the level of the horizontal line (second visual cue 40). An operator then successively introduces, from outside the module 1, the two indexing fingers 29. Each indexing finger 29 passes through a free orifice 41 of the rotor 2 and a hole 28 of the plate 25.

As shown in Figure 1 1, during step e), the module 1 is lowered so as to support the heads 12 of the screws 8 on the pins 27 of the plate 25. It is essential to support initially the rotor 2 (the heads 12 of the screws 8) then in a second time the stator 3 (flange 15 of the rectifier r4) in order to avoid any unexpected movement of the rotor 2 during the removal of the first handling tool 43. During this step e), it is possible to use the adjustment means of the first manipulation tool 43 in order to move the rotor 2 longitudinally with respect to the stator 3 or vice versa.

Tel qu’illustré sur la figure 12, lors de l’étape d), la bride 15 du redresseur r4 est mise en appui sur les surfaces d’appui 31 des supports 30. Les évidements 39 permettent le passage de la cinquième roue R5. Lors de cette étape d), il est possible de régler les supports 30 par rapport à la plateforme 33.

Le procédé comprend, entre les étapes f) et g), une étape f1 ) consistant à retirer le premier outillage de manipulation 43 du module 1.

The fan disc 4 is held during steps g) to i) via a second handling tool 51 on which the fan disc 4 is positioned and held, the second handling tool 51 comprising at least a pair of second opposed journals 52 , each of the second journals 52 being linked to an attachment bracket 46 of a lifting system 47. According to the embodiment illustrated in the figures and in particular in Figures 13 to 18, the second manipulation tool 51 comprises a first element 53 and a second lifting element 54 adapted to be fixed to the fan disc 4. The first and second lifting elements 53, 54 are arranged symmetrically with respect to the axis X. Each of the lifting elements 53, 54 comprises a trunnion 52, the trunnions 52 being adapted to be attached to a lifting system 47.The lifting system 47 comprises for example a lifting device (such as a winch) (not shown), a lifting beam 50 and two attachment brackets 46.

As illustrated in FIGS. 13 to 17, the fan disk 4 is extracted during step h) via three extractors 42 evenly distributed around the Z axis. Extraction is controlled by progressively unscrewing three nuts extractors 55 previously screwed onto three screws 8 each located close to one of the three extractors 42, and by gradually inserting shims 56 around the three screws 8 fitted with extraction nuts 55 between the fan disc 4 and the drum 5, the extraction nuts 55 and the wedges 56 being in a non-metallic material.

As illustrated in Figures 13 and 14, each extractor 42 comprises a first arm 57 and a second arm 58 hinged relative to each other, the first arm 57 resting on the fan disc 4 and the second arm 58 resting on the annular sealing piece 6. Each extractor 42 comprises a hydraulic actuator 59 articulated with respect to the first and second arms 57, 58, this hydraulic actuator 59 being configured to separate the first and second arms 57, 58 relative to each other, and thus vertically extract the fan disc 4 alone from the sealing piece 6 on which it is fitted.

The shims 56 make it possible to avoid any inclination of the fan disk 4 during a drop in hydraulic pressure at the level of the extractors 42. Advantageously, the extraction nuts 55 and the shims 56 are made of a non-metallic material, so not to damage the screws 8. The extraction nuts 55 and the wedges 56 are for example made of Teflon®.

As illustrated in Figures 15 to 17, step h) chronologically comprises the sub-steps consisting of:

h1) placing each extraction nut 55 at a distance D from an upper face 60 of a corresponding lobe 16 of the fan disc 4, the upper face 60 being placed facing the extraction nut 55; (Figure 15)

h2) actuating the three extractors 42 so that each upper face 60 is in contact with the corresponding extraction nut 55; (Figure 16) h3) arrange one or more wedges 56 having a total height H around each screw 8 provided with an extraction nut 55 between the fan disc 4 and the drum 5, the total height H being equal to the distance D. (Figure 17)

The sub-steps h1) to h3) are repeated so as to raise the fan disc 4 as much as possible relative to the drum 5. By way of example, the nut 9 is placed at a distance D=6 mm to start the extraction then the nut 9 is unscrewed by 3 mm at each repetition of steps h1) to h3) so that the fan disc 4 is 15 mm away from the drum 5 at the end of four cycles.

Such an extraction of the fan disc 4 makes it possible to obtain a vertical extraction and to prevent any contact between the screws 8 and the holes made in the lobes 16 of the fan disc 4.

As illustrated in FIGS. 13 to 18, during steps h) and i), the screws 8 are still in place (except for the two reference screws).

At the end of steps a) to i), module 1 is in its third state E3. The refitting (or the positioning) of the repaired fan disc (or of a new fan disc) is carried out directly on the module 1 as it was following the aforementioned process, namely in its third state E3 and placed on the tool 22. The same tool 22 thus makes it possible to remove the fan disc 4 but also to refit it. When refitting, care must be taken to orient the repaired fan disc correctly by aligning a mark associated with the repaired fan disc (for example a notch) with the marks on the other components of the module 1 . When installing the repaired fan disc,

WE CLAIMS

1. Tool (22) for removing a fan disc (4) alone from a module (1) of longitudinal axis (X) of a turbomachine comprising a rotor (2) and a stator (3), the rotor ( 2) comprising the fan disc (4), a drum (5) and an annular sealing piece (6) centered on the axis (X) and fixed to each other via a circular row of bolts (7) comprising each a screw (8) and a nut (9), each screw (8) passing through a retaining member (10) arranged inside the rotor (2), each retaining member (10) having at least two lugs ( 11) opposite arranged around a head (12) of the screw (8) and projecting relative to the head (12), the stator (3) being centered on the axis (X) and surrounding the drum ( 5), the stator (3) being longitudinally delimited by a rectifier (r4) arranged opposite the fan disc (4),the rectifier (r4) comprising an outer shroud (14) having a flange (15), the tool (22) with a vertical axis (Z) comprising:

- a frame (23) comprising ground support means (24);

- an annular plate (25) centered on the axis (Z) and integral with the frame (23), this plate (25) comprising first and second circular rows (26a, 26b) of pins (27) as well as two holes ( 28) arranged around the axis (Z) in a regular pitch, each of the two holes (28) being arranged between the first and second rows (26a, 26b), each of the pins (27) being configured to support the head ( 12) of a screw (8) so as not to damage the lugs (1 1) of the retaining members (10), each hole (28) being configured to receive an indexing pin (29) of the module (1 ) relative to the tool (22);

- at least three supports (30) distributed evenly around the axis (Z) and integral with the frame (23), each support (30) comprising a bearing surface (31), the bearing surfaces (31 ) being coplanar and being configured to support the flange (15) of the rectifier (r4) of the module (1), the three supports (30) being located vertically below the plate (25);

- A first visual marker (32) disposed on the frame (23) and configured to angularly orient the module (1) relative to the tool (22).

2. Tool (22) according to claim 1, characterized in that the tool (22) comprises a second visual cue (40) disposed on the frame (23) and configured to determine a vertical position of the module (1) from which the module (1) must be indexed relative to the tool (22).

3. Tool (22) according to one of the preceding claims, characterized in that each of the three supports (30) comprises a recess (39) configured to allow the passage of an annular row of blades (20) attached to the drum (5).

4. Method for removing a fan disc (4) alone from a module (1) of longitudinal axis (X) of a turbomachine comprising a rotor (2) and a stator (3), the rotor (2 ) comprising the fan disc (4), a drum (5) and an annular sealing piece (6) centered on the axis (X) and fixed to each other via a circular row of bolts (7) each comprising a screw (8) and a nut (9), each screw (8) passing through a retainer (10) arranged inside the rotor (2), each retainer (10) having at least two lugs (11 ) opposite arranged around a head (12) of the screw (8) and projecting relative to the head (12), the stator (3) being centered on the axis (X) and surrounding the drum (5 ), the stator (3) being longitudinally delimited by a rectifier (r4) disposed opposite the fan disc (4),the rectifier (r4) comprising an outer shroud (14) having a flange (15), by means of the tool (22) according to one of claims 1 to 3, the method comprising chronologically the steps consisting in:

a) removing two predetermined bolts (7) hereinafter referred to as reference bolts so as to have two free orifices (41) at the level of the rotor (2), the angular difference between the reference bolts being equal to angular difference between the two holes (28) of the plate (25);

b) positioning the module (1) above the tool (22) in a vertical position so that the longitudinal axis (X) of the module (1) is substantially vertical and substantially coaxial with the vertical axis (Z) of the tool (22), the fan disc (4) then being vertically above the drum (5);

c) aligning one of the free orifices (41) with the first visual cue (32) so as to orient the module (1) angularly with respect to the tool (22); d) indexing the module (1) relative to the tool (22) by introducing from outside the module (1) two indexing fingers (29), each indexing finger (29) passing through a free orifice ( 41) of the rotor (2) then a hole (28) of the plate (25);

e) resting the heads (12) of the screws (8) on the pins (27) of the plate (25), the drum (5) then surrounding the plate (25);

f) resting the flange (15) of the rectifier (r4) on the bearing surfaces (31) of the three supports (30);

g) remove all the nuts (9) from the bolts (7);

h) extracting the fan disk (4) alone in a controlled manner via at least one extractor (42);

i) remove the fan disc (4) alone.

5. Method according to claim 4, characterized in that the fan disk (4) is extracted during step h) via three extractors (42) distributed in a regular manner around the axis (Z), the extraction being checked by progressively unscrewing three extraction nuts (55) previously screwed onto three screws (8) each located close to one of the three extractors (42), and by progressively inserting wedges (56) around the three screws ( 8) provided with extraction nuts (55) between the fan disc (4) and the drum (5), the extraction nuts (55) and the wedges (56) being in a non-metallic material.

6. Method according to claim 5, characterized in that step h) comprises the sub-steps consisting of:

h1) placing each extraction nut (55) at a distance (D) from an upper face (60) of a corresponding lobe (16) of the fan disc (4), the upper face (60) being arranged extraction nut inspection window (55); h2) actuating the three extractors (42) so that each upper face (60) is in contact with the corresponding extraction nut (55);

h3) arrange one or more shims (56) having a total height (H) around each screw (8) provided with an extraction nut (55) between the fan disc (4) and the drum (5), the total height (H) being equal to the distance (D).

7. Method according to one of claims 4 to 6, characterized in that step d) is carried out when the flange (15) of the rectifier (r4) is located vertically at the level of a second visual reference (40) disposed on the frame (23) of the tool (22).

8. Method according to one of claims 4 to 7, characterized in that the module (1) is maintained during steps a) to f) via a first manipulation tool (43) on which is positioned and maintained the module ( 1), the first manipulation tool (43) comprising at least one pair of first opposed trunnions (44, 45), each of the first trunnions (44, 45) being linked to an attachment lug (46) of a system lift (47).

9. Method according to claim 8, characterized in that the first manipulation tool (43) is configured to make it possible to adjust longitudinally over a predetermined range the positioning of the rotor (2) vis-à-vis the stator (3) or vice versa .

10. Method according to one of claims 4 to 9, characterized in that the fan disc (4) is held during steps g) to i) via a second handling tool (51) on which is positioned and held the fan disc (4), the second manipulation tool (51) comprising at least one pair of opposed second journals (52), each of the second journals (52) being linked to an attachment bracket (46) of a system lift (47).