Patent Publication Number: US-2022220866-A1

Title: Tool for removing a fan disc from a module

Description:
TECHNICAL FIELD OF THE INVENTION 
     The present invention relates in particular to a tool for removing a fan disc alone from a module and to a method for removing a fan disc alone from a module by means of such a tool. 
     BACKGROUND 
     A turbomachine, such as a turbofan engine, comprises, from upstream to downstream in the direction of gas flow, a fan, one or more compressor stages (low pressure then high pressure), a combustion chamber, one or more turbine stages (high pressure then low pressure) and an exhaust nozzle. 
     Such a turbomachine corresponds to the assembly of a plurality of modules mounted in relation to each other. During a maintenance operation, various modules are dismounted and transported to different stations in order to undergo various maintenance operations (replacement of the wearing parts, replacement/repair of defective parts, etc.) necessary to put the turbomachine back into service. 
     In the following, we will focus on the “low-pressure compressor module”, hereinafter referred to as “module”. 
     Such a module is defined along a longitudinal axis X and comprises a rotor and a stator which are independent of each other. 
     The rotor comprises in particular a fan disc, a drum and an annular sealing part centered on the axis X and secured to each other by a circular row of bolts each comprising a screw and a nut. Each screw also passes through a retaining member arranged inside the rotor. Each retaining member has at least two opposing lugs arranged around a head of the screw and projecting from it, this retaining member allowing to hold the head of the corresponding screw in place when the associated nut is removed, which is itself located outside the rotor. The rotor also comprises several annular rows of vanes fitted to the drum and arranged one behind the other, each row of vanes being more commonly referred to as an impeller. 
     The stator is centered on the axis X and surrounds the drum. The stator comprises several compressor stator vanes annular assemblies interposed between the impellers. The first assembly of compressor stator vanes is associated with the fan so as to form the stage n°  1 , the following being each associated with an impeller so as to form the following stages. Each compressor stator vanes assembly comprises an inner shell and an outer shell connected to each other by an annular row of vanes. The outer shells of all the compressor stator vanes assemblies are flanged together. 
     The existing tools allow the entire module to be dismounted according to a determined method, whereby the fan disc is one of the elements of the module last removed. In other words, the removal of the fan disc cannot be done without a complete dismounting of the module. 
     There is an increasing demand for maintenance operations on the fan disc only, these maintenance operations requiring only the removal of the fan disc. 
     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 proceed to a complete dismounting of the module, to the detriment of the productivity. 
     The objective of the present invention is thus to propose, on the one hand, a tool for removing a fan disc alone from a module and, on the other hand, a method for removing a fan disc alone from a module by means 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 having a longitudinal axis X of a turbomachine comprising a rotor and a stator, the rotor comprising the fan disc, a drum and an annular sealing part centered on the axis X and secured to one another 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 least two opposing lugs arranged around a head of the screw and projecting with respect to the head, the stator being centered on the axis X and surrounding the drum, the stator being longitudinally delimited by a compressor stator vanes assembly arranged opposite the fan disc, the compressor stator vanes assembly comprising an outer shell having a flange, the tool having a vertical axis Z comprising: 
     a frame comprising ground support means; 
     an annular plate centered on the axis Z and secured to the frame, this plate comprising first and second circular rows of pins as well as two holes arranged around the axis Z at a regular pitch, each of the two holes being arranged between the first and second rows, each of the pins being configured to bear 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 in a regular manner around the axis Z and secured to the frame, each support comprising a bearing surface, the bearing surfaces being coplanar and being configured to support the flange of the compressor stator vanes assembly of the module, the three supports being vertically located below the plate; 
     a first visual marker arranged on the frame and configured to angularly orient the module relative to the tool. 
     Such a tool allows the removal of the fan disc alone while keeping the rest of the module assembled. Thus, during a maintenance operation involving only the fan disc, such a tool allows a significant gain in productivity. 
     In addition, such a tool allows the removal of the fan disc alone without damaging other components of the module, in particular the retaining members and the screws. 
     Such a tool can also be used to re-install the repaired fan disc (or to install a new fan disc) on 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 alone or in combination with each other: 
     the first visual marker is a vertical line; 
     the tool comprises a second visual marker arranged on the frame and configured to determine a vertical position of the module from which the module is to be indexed relative to the tool; 
     the second visual marker is a horizontal line; 
     each of the three supports comprises a recess configured to allow the passage of an annular row of vanes fitted to the drum. 
     The present invention also relates to a method for removing a fan disc alone from a module having a longitudinal axis X of a turbomachine comprising a rotor and a stator, the rotor comprising the fan disc, a drum and an annular sealing part centered on the axis X and secured to one another 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 least two opposing lugs arranged about a head of the screw and projecting with respect to the head, the stator being centered on the axis X and surrounding the drum, the stator being longitudinally delimited by a compressor stator vanes assembly arranged opposite the fan disc, the compressor stator vanes assembly comprising an outer shell having a flange, by means of the tool as previously described, the method comprising chronologically the steps of: 
     a) removing two predetermined bolts hereinafter referred to as reference bolts so as to have two free orifices at the level of the rotor, the angular distance between the reference bolts being equal to the angular distance 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 above the drum; 
     c) aligning one of the free orifices with the first visual marker so as to angularly orient the module with respect to the tool; 
     d) indexing the module with respect to the tool by introducing two indexing fingers from the outside of the module, each indexing finger passing through a free orifice of the rotor and then through a hole of the plate; 
     e) abutting the heads of the screws on the pins of the plate, the drum then surrounding the plate; 
     f) abutting the flange of the compressor stator vanes assembly on the bearing surfaces of the three supports; 
     g) removing all the nuts from the bolts; 
     h) extracting in a controlled manner the fan disc alone via at least one extractor; 
     i) removing the fan disc alone. 
     Such a method allows the removal of the fan disc alone, by means of the tool, while keeping the rest of the module assembled. Thus, during a maintenance operation involving only the fan disc, the implementation of such a method allows a significant gain in productivity. 
     In addition, such a method allows the removal of the fan disc alone without damaging the other components of the module, in particular the retaining members and the screws. 
     The method according to the invention may comprise one or more of the following characteristics and/or steps, taken alone or in combination with each other: 
     the fan disc is extracted during the step h) via three extractors distributed in a regular manner around the axis Z, the extraction being controlled by progressively unscrewing three extraction nuts previously screwed onto three screws each located close to one of the three extractors, and by progressively inserting wedges around the three screws having the extraction nuts between the fan disc and the drum, the extraction nuts and the wedges being in a non-metallic material; 
     the step h) comprises the sub-steps of: 
     h1) arranging each extraction nut at a distance D from a upper face of a corresponding lobe of the fan disc, the upper face being arranged opposite the extraction nut; 
     h2) actuating the three extractors so that each upper face is in contact with the corresponding extraction nut; 
     h3) arranging one or more wedges having a total height H around each screw having an extraction nut between the fan disc and the drum, the total height H being equal to the distance D, 
     the step d) is carried out when the flange of the compressor stator vanes assembly is located vertically at the level of a second visual marker arranged on the frame of the tool; 
     the module is held during the steps a) to f) via a first handling tooling on which the module is positioned and held, the first handling tooling comprising at least one pair of opposing first trunnions, each of the first trunnions being linked to a bracket of a lifting system; 
     the first handling tooling is configured to allow the positioning of the rotor relative to the stator to be adjusted longitudinally over a predetermined range or vice versa; 
     the fan disc is held during the steps g) to i) via a second handling tooling on which the fan disc is positioned and held, the second handling tooling comprising at least one pair of opposing second trunnions, each of the second trunnions being linked to a bracket of a lifting system. 
    
    
     
       BRIEF DESCRIPTION OF FIGURES 
       The invention will be better understood and other details, characteristics and advantages of the present invention will become clearer from the following description made by way of non-limiting example and with reference to the attached drawings, in which: 
         FIG. 1  is a cutaway and perspective view showing the module in a second state E 2 ; 
         FIG. 2  is an axial half-section view showing the module in a first state E 1 ; 
         FIG. 3  is a detail view of  FIG. 2  showing in particular the assembly of a fan disc, a drum and an annular sealing part via bolts; 
         FIG. 4  is a perspective view of a tool for removing the fan disc of the module shown in  FIGS. 1 to 3 ; 
         FIG. 5  is a detail view of  FIG. 4 ; 
         FIG. 6  is a perspective view of the module positioned in a horizontal position as part of a method for removing a fan disc from a module shown in  FIGS. 1 to 3  by means of a tool shown in  FIGS. 4 and 5 ; 
         FIG. 7  is a perspective view showing a step of removing two reference bolts so that two free orifices are available; 
         FIG. 8  is a detail view of  FIG. 7  showing a free orifice; 
         FIG. 9  is a perspective view showing a step of aligning one of the free orifices with a first visual marker of the tool; 
         FIG. 10  is a perspective view showing a step of indexing the module with respect to the tool; 
         FIG. 11  is a half-axial sectional view illustrating a step consisting in abutting screw heads on pins of a plate of the tool; 
         FIG. 12  is a perspective view illustrating a step of abutting a flange of a compressor stator vanes assembly of the module onto bearing surfaces of supports; 
         FIG. 13  is a perspective view showing a step of extracting in a controlled manner the fan disc; 
         FIG. 14  is a detail view of  FIG. 13 ; 
         FIG. 15  is a perspective view showing a sub-step of arranging extraction nuts on screws; 
         FIG. 16  is a perspective view showing a sub-step of actuating extractors; 
         FIG. 17  is a perspective view showing a sub-step of interposing one or more wedges; 
         FIG. 18  is a perspective view showing a step of removing the fan disc alone. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIGS. 1 and 2  show 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  which are independent of each other, and in other words the rotor  2  and the stator  3  are not guided relative to each other via a bearing, for example. The longitudinal axis X of the module  1  is coincident with the longitudinal axis of the turbomachine when the module  1  is in place in the turbomachine. 
     In the present application, the terms “inner” and “outer” associated with the various components of the module  1  are defined with respect to the longitudinal axis X. 
     More specifically, the rotor  2  comprises a fan disc  4 , a drum  5  and an annular sealing part  6  centered on the axis X and secured to each other by 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 opposing lugs  11  arranged around a head  12  of the screw  8  and projecting from 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 compressor stator vanes assembly r 4  arranged opposite the fan disc  4 , the compressor stator vanes assembly r 4  comprising an outer shell  14  having a flange  15 . 
     According to the embodiment illustrated in the figures and in particular in  FIGS. 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 vane (not included in the module  1 ). The fan disc  4  has a plurality of lobes  16  evenly distributed around the axis X at the level of its downstream end, these lobes  16  forming a flange. The fan disc  4  is partially shown in  FIG. 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  passes successively from the head  12  to the corresponding nut  9  through a through hole made in the corresponding retaining member  10 , through a through hole made in the sealing part  6 , through a through hole made in a flange of the drum  5  and through a through hole made in a lobe  16  of the fan disc  4 . The screws  8  have a square head  12 . 
     As illustrated in  FIG. 3 , each retaining member  10  is disposed longitudinally between the head  12  of the corresponding screw  8  and the sealing part  6 . Each retaining member  10  comprises four lugs  11  facing each other in pairs which surround the head  12  of the corresponding screw  8 , the lugs  11  projecting from the head  12 . The retaining members  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  allows to hold 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 press-fitted on a projection  18  of the fan disc  4  at the level of its inner end and hooked onto a projection  19  of the drum  5  at the level of its outer end. 
     As illustrated in  FIG. 2 , the rotor  2  also comprises four annular rows of vanes  20  fitted to the drum  5  and arranged one behind the other, each row of vanes  20  being more commonly referred to as an “impeller”. The four impellers are respectively numbered, from upstream to downstream, as impeller R 2  (for impeller n°  2 ) to impeller R 5  (for impeller n°  5 ), with impeller R 1  (for impeller n°  1 ) being considered the fan. 
     According to the embodiment shown in the figures and in particular in  FIG. 2 , the stator  3  comprises five compressor stator vanes annular assemblies interposed between the impellers. The five compressor stator vanes assemblies are numbered, from upstream to downstream, compressor stator vanes assembly r 1  (for compressor stator vanes assembly n°  1 ) to compressor stator vanes assembly r 5  (for compressor stator vanes assembly n°  5 ). The first assembly of compressor stator vanes r 1  is associated with the fan so as to form the stage n°  1 , the following ones being each associated with an impeller (impellers R 2  to R 5 ) so as to form the following stages (stage n°  2  to stage n°  5 ). Each compressor stator vanes assembly r 1  to r 5  comprises an inner shell  13  and an outer shell  14  connected to each other by an annular row of vanes  21 . The vanes  21  are for example welded to the inner and outer shells  13 ,  14  so as to form a mechanically welded assembly. The outer shells  14  of all the compressor stator vanes assemblies r 1  to r 5  are flanged together. 
     By convention, in the present application, the terms “upstream” and “downstream” are defined in relation to the direction of flow of the gases in the module  1 , the gases passing successively through the different stages. 
       FIG. 2  illustrates the module  1  in a first state E 1  corresponding to the module  1  as it is when it is received to undergo a maintenance operation. 
       FIG. 1  shows the module  1  in a second state E 2  in which the fifth assembly of compressor stator vanes r 5  has been removed, the outer shell  14  of the fourth assembly of compressor stator vanes r 4  having a free flange  15 . The second state E 2  corresponds to the state of the module  1  for the removal of the fan disc  4  alone. 
     A module  1  in a third state E 3  corresponds to a module  1  in a second state E 2  from which the fan disc  4  has been removed. 
     The fan disc  4  alone is removed from a module  1  in a second state E 2  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 axis Z and secured to the frame  23 , this plate  25  comprising first and second circular rows  26   a,    26   b  of pins  27  as well as two holes  28  arranged around the axis Z at a regular pitch, each of the two holes  28  being arranged between the first and second rows  26   a,    26   b,  each of the pins  27  being configured to bear 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 finger  29  of the module  1  relative to the tool  22 ; 
     at least three supports  30  distributed in a regular manner around the axis Z and secured to 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 compressor stator vanes assembly r 4  of the module  1 , the three supports  30  being vertically located below the plate  25 ; 
     a first visual marker  32  arranged on the frame  23  and configured to angularly orient the module  1  with relative to the tool  22 . 
     In the present application, the terms “lower” and “upper” associated with the various components of the tool  22  are defined with respect to the vertical axis Z. Further, in the present application, the terms “inner” and “outer” associated with the various components of the tool  22  are defined with respect to the vertical axis Z. 
     According to the embodiment illustrated in the figures and in particular in  FIGS. 4 and 5 , the frame  23  comprises a platform  33  on which the supports  30  rest and a barrel  34  on which the plate  25  rests. The platform  33  is planar, perpendicular to the axis Z and substantially triangular, each support  30  being arranged at the level of a protruding angular portion of the platform  33 . The barrel  34  is centered on the axis Z and rises from the platform  33 . The ground support means  24  comprise here three feet evenly distributed around the axis Z. 
     The plate  25  comprises an annular upper surface  35  delimited by two rims  36 , the rims  36  being configured to hold the ends of the sealing part  6  when the repaired fan disc (or a new fan disc) is press-fitted on a module  1  in a third state E 3 . The pins  27  of the first and second rows  26   a,    26   b  are arranged on the upper surface  35 . The first and second rows  26   a,    26   b  have the same number of pins  27  (in this case ten pins) and are symmetrical with respect to the axis Z. The holes  28  are thus also symmetrical with respect to the axis Z. The pins  27  as well as the two holes  28  are arranged equidistant from the axis Z. The holes  28  are blind holes opening at the level of the upper surface  35 . The angular distance between the two holes  28  is 180 degrees. The indexing fingers  29  have been shown in  FIG. 5  to indicate the location of the holes  28 . The plate  25  comprises a thermal shield  37  at the level of its inner surface, so as to protect the plate  25  from the heat when the repaired fan disc (or a new fan disc) is press-fitted. In fact, to perform the press-fitting, the sealing part  6  is heated to a predetermined temperature. 
     The bearing surfaces  31  lie in a common plane perpendicular to the axis Z. Each bearing surface  31  is located at an upper end of the corresponding support  30 . Each bearing surface  31  is in the form of an annular sector and is delimited on the outside by an edge  38 . The three supports  30  are arranged in relation to the pins  27  in such a way that the heads  12  are supported before the flange  15  when the module  1  is positioned on the tool  22 . Each support  30  comprises a recess  39  oriented on the side of the vertical axis Z and configured to allow the passage of the fifth assembly of compressor stator vanes R 5 , when the module  1  is positioned on the tool  22 . The supports  30  may be adjustable relative to the platform  33  in a direction perpendicular to the axis Z. 
     The first visual marker  32  is in the form of a vertical line  32  arranged on the periphery of the barrel  34  and the periphery of the plate  25 , said vertical line  32  being configured to angularly orient the module  1  relative to the tool  22 . This first visual marker  32  may be obtained via the application of one or more self-adhesive strips. 
     The tool  22  comprises a second visual marker  40  in the form of a horizontal line  40  arranged on the periphery of the barrel  34 , said horizontal line  40  being configured to determine a vertical position of the module  1  from which the module  1  is to be indexed relative to the tool  22 . Here the horizontal line crosses the vertical line. In the same manner as the first visual marker  32 , this second visual marker  40  may be obtained via the application of one or more self-adhesive strips. 
     Advantageously, the plate  25  and the supports  30  are made of a non-metallic material, so as not to damage the module  1 . The plate  25  and the supports  30  are made of Teflon® for example. 
     The removal of a fan disc  4  alone from a module  1  in a second state E 2  by means of the tool  22  is carried out according to a method comprising chronologically the steps of: 
     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 distance between the reference bolts being equal to the angular distance between the two holes  28  of the plate  25 ; ( FIGS. 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 disc  4  then being vertically above the drum  5 ; 
     c) aligning one of the free orifices  41  with the first visual marker  32  so as to angularly orient the module  1  with respect to the tool  22 ; ( FIG. 9 ) 
     d) indexing the module  1  with respect to the tool  22  by introducing from the outside of the module  1  two indexing fingers  29 , each indexing finger  29  passing through a free orifice  41  of the rotor  2  and then through a hole  28  of the plate  25 ; ( FIG. 10 ) 
     e) abutting the heads  12  of the screws  8  on the pins  27  of the plate  25 , the drum  5  then surrounding the plate  25 ; ( FIG. 11 ) 
     f) abutting the flange  15  of the compressor stator vanes assembly r 4  on the bearing surfaces  31  of the supports  30 ; ( FIG. 12 ) 
     g) removing all the nuts  9  from the bolts  7 ; 
     h) extracting in a controlled manner the fan disc  4  alone via at least one extractor  42 ; ( FIGS. 13 to 17 ) 
     i) removing the fan disc  4  alone. ( FIG. 18 ) 
     As mentioned above, the method is implemented on a module  1  in a second state E 2 , and in other words a module  1  from which the fifth assembly of compressor stator vanes r 5  has been removed. 
     The module  1  is held during the steps a) to f) via first handling tooling  43  on which the module  1  is positioned and held, the first handling tooling  43  comprising at least one pair of opposing first trunnions  44 ,  45 , each of the first trunnions  44 ,  45  being linked to a bracket  46  of a lifting system  47 . 
     According to the embodiment illustrated in the figures and in particular in  FIGS. 6 to 12 , the first handling tooling  43  comprises a first portion  48  adapted to be secured to the rotor  2  of the module  1  and a second portion  49  adapted to be secured to the stator  3  of the module  1 . The first handling tooling  43  comprises adjusting means configured to adjust longitudinally over a predetermined range the positioning of the first portion  48  (rotor  2 ) relative to the second portion  49  (stator  3 ) or vice versa. As mentioned above, the rotor  2  and the stator  3  are independent of each other. This longitudinal adjustment is used in particular to ensure that the heads  12  of the screws  8  are supported before the flange  15  when the module  1  is positioned on the tool  22 . The first handling tooling  43  comprises a pair of median trunnions  44  and a pair of end trunnions  45 . Each of the pairs of trunnions  44 ,  45  is adapted to be secured to an independent lifting system  47 . Each lifting system  47  comprises, for example, a lifting device (such as a winch) (not shown), a spreader  50  and two brackets  46 . 
     Advantageously, as illustrated in  FIGS. 6 to 8 , during the 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  22  rests. The first handling tooling  43  is connected to a first lifting system  47  via the median trunnions  44  and to a second lifting system  47  via the end trunnions  45 . 
     As illustrated in  FIGS. 6 to 8 , during the step a), an operator removes the bolts  7  placed at 3 o&#39;clock and 9 o&#39;clock by analogy with the dial of a clock. The bolts  7  placed at 3 o&#39;clock and 9 o&#39;clock are thus considered to be the reference bolts. The angular distance between the two reference bolts is equal to the angular distance between the two holes  28  of the plate  25 , namely 180 degrees. At the end of the step a), the free orifices  41  are now at 3 o&#39;clock and 9 o&#39;clock. 
     As illustrated in  FIGS. 9 to 12 , during the steps b) to f), the module  1  is in a vertical position with the fan disc  4  vertically above the drum  5 . The first handling tooling  43  is connected to a single lifting system  47  via the end trunnions  45 . 
     As illustrated in  FIG. 9 , during the step c), an operator controls the first handling tooling  43  so as to align one of the free orifices  41  (identifiable via the absence of the nut) with the vertical line (first visual marker  32 ). This step c) allows to align the two free orifices  41  with the two holes  28  of the plate  25 . 
     As shown in  FIG. 10 , the step d) is carried out when the free flange  15  of the compressor stator vanes assembly r 4  is vertically at the level of the horizontal line (second visual marker  40 ). An operator then inserts the two indexing fingers  29  successively from outside the module  1 . Each indexing finger  29  passes through a free orifice  41  of the rotor  2  and a hole  28  of the plate  25 . 
     As illustrated in  FIG. 11 , during the step e), the module  1  is lowered so as to abut the heads  12  of the screws  8  on the pins  27  of the plate  25 . It is essential to first abut the rotor  2  (the heads  12  of the screws  8 ) and then the stator  3  (flange  15  of the compressor stator vanes assembly r 4 ) in order to avoid any unexpected movement of the rotor  2  when the first handling tooling  43  is removed. During this step e), it is possible to use the adjusting means of the first handling tooling  43  in order to longitudinally displace the rotor  2  relative to the stator  3  or vice versa. 
     As illustrated in  FIG. 12 , during the step d), the flange  15  of the compressor stator vanes assembly r 4  is brought to rest on the bearing surfaces  31  of the supports  30 . The recesses  39  allow the passage of the fifth impeller R 5 . During this step d), the supports  30  can be adjusted relative to the platform  33 . 
     The method comprises, between the steps f) and g), a step f1) of removing the first handling tooling  43  from the module  1 . 
     The fan disc  4  is held during the steps g) to i) via a second handling tooling  51  on which the fan disc  4  is positioned and held, the second handling tooling  51  comprising at least one pair of opposing second trunnions  52 , each of the second trunnions  52  being linked to a bracket  46  of a lifting system  47 . 
     According to the embodiment illustrated in the figures and in particular in  FIGS. 13 to 18 , the second handling tooling  51  comprises a first lifting element  53  and a second lifting element  54  adapted to be secured 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 spreader  50  and two brackets  46 . 
     As illustrated in  FIGS. 13 to 17 , the fan disc  4  is extracted during the step h) via three extractors  42  distributed in a regular manner around the axis Z. The extraction is controlled 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  having the extraction nuts  55  between the fan disc  4  and the drum  5 , the extraction nuts  55  and the wedges  56  being made of a non-metallic material. 
     As illustrated in  FIGS. 13 and 14 , each extractor  42  comprises a first arm  57  and a second arm  58  hinged to each other, the first arm  57  bearing on the fan disc  4  and the second arm  58  bearing on the annular sealing part  6 . Each extractor  42  comprises a hydraulic actuator  59  articulated relative to the first and second arms  57 ,  58 , this hydraulic actuator  59  being configured to move the first and second arms  57 ,  58  away from each other, thereby vertically extracting the fan disc  4  alone from the sealing part  6  on which it is press-fitted. 
     The wedges  56  allow to prevent the fan disc  4  from inclining during a drop in hydraulic pressure at the level of the extractors  42 . 
     Advantageously, the extraction nuts  55  and the wedges  56  are made of a non-metallic material, so as not to damage the screws  8 . The extraction nuts  55  and the wedges  56  are made of Teflon®, for example. 
     As illustrated in  FIGS. 15-17 , the step h) chronologically comprises the sub-steps of: 
     h1) arranging each extraction nut  55  at a distance D from a upper face  60  of a corresponding lobe  16  of the fan disc  4 , the upper face  60  being arranged opposite the extraction nut  55 ; ( FIG. 15 ) 
     h2) actuating the three extractors  42  so that each upper face  60  is in contact with the corresponding extraction nut  55 ; ( FIG. 16 ) 
     h3) arranging one or more wedges  56  having a total height H around each screw  8  having an extraction nut  55  between the fan disc  4  and the drum  5 , the total height H being equal to the distance D. ( FIG. 17 ) 
     The sub-steps h1) to h3) are repeated so that the fan disc  4  is raised as much as possible above the drum  5 . For example, the nut  9  is set at a distance D=6 mm to start the extraction and then the nut  9  is unscrewed by 3 mm at each repetition of the steps h1) to h3) so that the fan disc  4  is 15 mm away from the drum  5  after four cycles. 
     Such an extraction of the fan disc  4  allows to provide a vertical removal and prevents contact between the screws  8  and the holes embodied in the lobes  16  of the fan disc  4 . 
     As shown in  FIGS. 13 to 18 , during the steps h) and i), the screws  8  are still in place (except for the two reference screws). 
     At the end of the steps a) to i), the module  1  is in its third state E 3 . The re-installation (or the placement) of the repaired fan disc (or of a new fan disc) is performed directly on the module  1  as it was after the above-mentioned method, i.e. in its third state E 3  and placed on the tool  22 . The same tool  22  allow to be used to remove the fan disc  4  and also to install it again. During the re-installation, care must be taken to correctly orient the repaired fan disc by aligning a mark associated with the repaired fan disc (e.g. a notch) with the marks on the other components of the module  1 . When the repaired fan disc is re-installed, the sealing part  6  of the module  1  is heated so as to allow the repaired fan disc can be press-fitted into the sealing part  6  of the module  1 .