PROTECTION TOOLING FOR A TURBOMACHINE PART

Abstract

The invention relates to a tool (50) for protecting a part (26) of a turbomachine, the tool being generally annular in shape, split so as to present two free circumferential ends (54), and comprising: - a first radially external protective part (60); - a second radially internal protective part (62);- an intermediate protective part (64) connecting the parts (60, 62), and defining a housing (66) intended to receive a portion (40) of said part to be protected, projecting radially inwards, the tooling being configured to be brought from a nominal unassembled configuration, to a constrained unassembled configuration obtained by elastic deformation of the tooling, via the application of a stress (56) on the tooling so as to decrease its radial extent, and the tooling also being configured to be brought from the constrained unassembled configuration to a configuration assembled on the part to be protected (26), by releasing the stress (56). Figure for the abbreviation: Fig. 9;

Description

Title of the invention: PROTECTIVE TOOL FOR A TURBOMACHINE PART technical field

[0001] The invention relates to the field of turbomachinery, preferably aircraft turbomachinery, and more specifically to the field of tooling for protecting turbomachine parts. Such tooling is designed to be fitted onto the turbomachine parts to be protected, during the assembly and disassembly of these parts, and / or during their handling, for example during maintenance.

[0002] The invention finds applications for parts of any type of turbomachine, such as turbojets or aircraft turboprops. Prior art

[0003] Certain turbomachine parts may have portions that are susceptible to damage, for example during dismantling prior to maintenance operations.

[0004] By way of example, some parts include mounting flanges assembled within the turbomachine using an annular ring of bolts. To remove the part, the bolts must first be loosened and then removed. Loosening may require the application of high torque, which could cause a sudden jolt with the loosening tool. This tool could then come into contact with the part being removed and generate defects such as scratches, dents, or similar marks, which could lead to the part being deemed non-conforming. Similar risks exist during the assembly of the part, or during its handling and maintenance.

[0005] To date, few protective solutions have been deployed in maintenance workshops. Some solutions involve protecting parts with hook-and-loop fasteners, allowing the protection to be held in place around the part.

[0006] However, implementing this type of solution can be time-consuming. Moreover, it sometimes remains impossible, especially when the part is still mounted within the turbomachine, and there is no accessibility around this part. Description of the invention

[0007] To address at least partially the drawbacks mentioned above, the invention first relates to a tool for protecting a turbomachine component, the tool being configured to be positioned on the component at least during one of the following steps: mounting the component in the turbomachine, dismounting the component, and handling the component. being generally annular in shape, split so as to present two free circumferential ends, and comprising, in semi-transverse section:

[0008] - a first radially external protective part;

[0009] - a second radially internal protective part;

[0010] - an intermediate protective part connecting the first and second parts, and defining a housing intended to receive a portion of said room to be protected, projecting radially inwards,

[0011] the tooling being configured to be brought from a nominal unassembled configuration, to a constrained unassembled configuration obtained by elastic deformation of the tooling, via the application of a constraint on the tooling so as to decrease its radial extent, and the tooling also being configured to be brought from the constrained unassembled configuration to an assembled configuration on the part to be protected, by releasing said constraint.

[0012] The invention is advantageous in that it allows for reliable and easy mounting of the protective tooling on the part to be protected. Furthermore, its design allows it to be mounted on certain parts even when they are still assembled within the turbomachine, and when no protective device can be installed due to lack of accessibility around these parts. By offering the possibility of installing the protective tooling early in the part maintenance process, the risks of damage and non-conformity of this part are advantageously reduced.

[0013] The invention preferably provides for at least one of the following optional technical features, implemented individually or in combination.

[0014] Preferably, the protective tooling is self-supporting, in that its retention in place on the workpiece is ensured by its own shape. This avoids the use of hook and loop fasteners and allows for quick assembly of the tooling onto the workpiece, which is preferably done manually.

[0015] Preferably, in the nominal unassembled configuration, the intermediate protective part has, on the side of the second radially internal protective part, a junction wall that is convex radially outwards, and extending radially outwards beyond an internal radial bottom of the housing defined by this intermediate protective part, and / or in the nominal unassembled configuration, the second radially internal protective part extends radially inwards beyond the intermediate protective part.

[0016] Preferably, each of the first and second protective parts has an over-thickened bearing area. Each bearing area thus constitutes a preferred bearing area on the part to be protected, so that some clearance may remain between the part and the other parts of the tooling, near these bearing areas. This clearance allows to adapt to slight differences in shape and / or dimensions that may be encountered on parts of the same reference.

[0017] Preferably, each of the two free circumferential ends has a gripping member, preferably an orifice, so as to facilitate manual gripping by an operator, or with the help of a tool for applying stress to the protective tooling.

[0018] The invention also relates to an assembly comprising a turbomachine part, as well as protective tooling as described above, intended to protect said part at least during one step among a step of mounting the part within the turbomachine, a step of dismantling this part, and a step of handling the part.

[0019] Preferably, the turbomachine part is a connecting piece between a turbine rotor and a turbomachine shaft, the connecting piece comprising:

[0020] - a mounting flange on the turbine rotor, the flange having orifices of assemblies intended to be traversed by mounting components;

[0021] - a part of generally conical shape extending radially inwards from from a radially internal end of the mounting flange; and

[0022] - at the level of a junction zone between the fixing flange and the shaped part general conical, a portion of said part to be protected, the portion to be protected projecting radially inwards, and preferably also in a longitudinal direction.

[0023] Preferably, the protruding portion to be protected corresponds to a mechanically reinforced area of ​​the part, possibly equipped with a balancing system.

[0024] The invention also relates to a method for assembling such protective tooling onto a turbomachine part, comprising the following steps:

[0025] - transition of the tooling from its nominal unassembled configuration to its unassembled constraint figure obtained by elastic deformation of the tooling, via the application of stress on this tooling so as to decrease its radial extent;

[0026] - transition of the tooling from its unassembled constrained configuration to its assembly on the part to be protected, by release of said constraint, passage during which a protruding portion to be protected of said part is inserted into the housing defined by the intermediate part of protection of the tooling.

[0027] Finally, the invention also relates to a method for maintaining a turbomachine part, comprising the following steps:

[0028] a) a disassembly step for this part;

[0029] b) a step of handling the part, from the turbomachine to a station of maintenance;

[0030] c) a part maintenance step;

[0031] d) a step of handling the part towards the turbomachine;

[0032] e) a step of mounting the part on the turbomachine;

[0033] and also comprising the implementation of the method of assembling a protective tooling as described above, on said turbomachine part, before the implementation of any step among steps a) to e), the method also comprising a disassembly of the protective tooling, after the implementation of said step, or of one of the steps a) to e) which follow it.

[0034] In this regard, it is noted that the assembly of the protective tooling is preferably carried out before the disassembly step of this part, and that this tooling is preferably kept on the part at least during part of the handling step of the part, from the turbomachine to the maintenance station. Furthermore, it is noted that the assembly and disassembly cycle of the tooling can be repeated during the same maintenance procedure for the part, without departing from the scope of the invention.

[0035] Furthermore, it is noted that the protective tooling could be installed even before the part is disassembled, as early as possible in the procedure, and particularly in its modular state, even if the maintenance procedure does not involve disassembling the part to be protected. For example, the tooling can be installed before loosening the bolts of the cone connection.

[0036] Furthermore, this protective tooling could also be installed for inspection in a modular state, without implementing the maintenance procedure for dismantling the cone. For example, if during maintenance the disc must be removed, but the cone must remain assembled, it may be advisable to protect the area during the inspection of the low-pressure turbine, without dismantling the cone.

[0037] Other advantages and features of the invention will appear in the detailed, non-limiting description below. Brief description of the drawings

[0038] The detailed description that follows refers to the attached figures in which:

[0039] [Fig.1] is a schematic longitudinal cross-sectional view of an aircraft turbomachine;

[0040] [Fig.2] is a more detailed view, in longitudinal half-section, of part of a turbine of the turbomachine shown in the previous figure;

[0041] [Fig.3] is a more detailed view, in longitudinal half-section, of a part of the turbine shown in the previous figure, showing in particular a turbine part to be protected;

[0042] [Fig.4] is a perspective view of a part of the turbine piece shown in the previous figure, equipped with protective tooling so as to form an assembly according to a preferred embodiment of the invention;

[0043] [Fig.5] is a partial, longitudinal half-sectional view of the assembly shown on the previous figure;

[0044] [Fig.6] is a front view of the protective tooling, in a configuration nominal unassembled, and in a constrained unassembled configuration obtained by elastic deformation of this tooling;

[0045] [Fig.7] is a partial view, in longitudinal half-section, of the protective tooling according to another preferred embodiment of the invention;

[0046] [Fig. 8],

[0047] [Fig.9] are views showing the protective tooling in different configurations Figures, during the assembly process of this tooling onto the turbine component. Detailed description of implementation methods

[0048] With reference first to [Fig. 1], an aircraft turbomachine 1 is shown. This is a twin-spool turbofan engine. However, it could be a turbomachine of another type, for example a single-spool turbofan engine, or even a turboprop, without departing from the scope of the invention.

[0049] The turbomachine 1 has an axis 2 around which its various components extend, this axis being called the central longitudinal axis of the turbomachine. Hereafter, the terms "upstream" and "downstream" are defined with respect to a general direction 5 of gas flow through the propulsion assembly 1 when it generates direct thrust, this direction being parallel or substantially parallel to the axis 2. These terms "upstream" and "downstream" could respectively be replaced by the terms "front" and "rear," with the same meaning. Furthermore, the turbomachine 1 is represented in a coordinate system formed by three mutually orthogonal directions, namely the longitudinal direction L parallel to the axis 2, the circumferential direction C, and the radial direction R.

[0050] The turbomachine 1 comprises, from upstream to downstream along the main direction 5 of gas flow, a blower 3, a low pressure compressor 4, a high pressure compressor 6, a combustion chamber 11, a high pressure turbine 7 and a low pressure turbine 8.

[0051] Conventionally, after passing through the blower, the air splits into a central primary flow 12a and a secondary flow 12b which surrounds the primary flow. The primary flow 12a flows into a main gas circulation channel 14a passing through the compressors 4, 6, the combustion chamber 11 and the turbines 7, 8. The secondary flow 12b, on the other hand, flows into a secondary channel 14b delimited radially outwards by an engine casing, surrounded by a nacelle 9.

[0052] Figure 2 represents a portion of one of the two turbines 7, 8 mentioned above, of The low-pressure turbine 8, located at the rear of the turbomachine, is preferred. Conventionally, the turbine comprises several turbine stages, each formed by The assembly consists of a stator 20, called a turbine distributor, and a rotating wheel 22 equipped with an annular ring of moving blades. The rotating wheels 22 are connected to each other to form a turbine rotor 23. This rotor is rotationally coupled to a turbomachine shaft 24, here the low-pressure motor shaft, centered on the axis 2 and possibly made of several interconnected sections. To achieve this coupling, a connecting piece 26 is used, one radially external end of which is fixed to the turbine rotor 23, and one radially internal end of which is fixed to the shaft 24, for example at a junction 28 between two sections of this shaft. This fixing can be achieved by an annular ring of bolts 29. The connecting piece 26 is also called a "cone-trunk" because of its shape.

[0053] More specifically with reference to figures 2 to 4, the connecting piece 26 comprises several parts, described below, which are joined together.

[0054] First, this part 26 is annular, centered on the axis 2, and it includes a flange 30 for mounting on the turbine rotor 23. This flange 30, preferably radially or substantially radially oriented, has mounting holes 32 through which mounting elements 33 pass, of the bolt type forming an annular ring of mounting elements. The flange 30 may be scalloped, as shown in [Fig. 4].

[0055] Starting from a radially internal end of the mounting flange 30, the connecting piece 26 comprises a generally conical portion 34, centered on the axis 2 and opening axially downstream. The conical portion 34 and the mounting flange 30 are preferably made as a single piece.

[0056] The connecting piece 26 also includes, at the level of a junction zone between the flange 30 and the conical part 34, a portion 40 to be protected, which is located in radial projection towards the inside, and also in the longitudinal direction L, towards the downstream.

[0057] The projecting portion to be protected 40 corresponds to a mechanical reinforcement zone 42 of the part 26, optionally equipped with a balancing system 44. This system may, for example, take the form of a mass balancing bead radially inwardly applied to the reinforcement zone 42, formed by an excess of material, in particular an axial excess on the downstream side. The projecting portion to be protected 40 is annular in shape, centered on the axis 2, and also referred to as a "dropper" due to its shape, even though it is not normally intended to perform such a function. In a half-section view such as that shown in [Fig. 3], the projecting portion 40 takes, for example, the form of a lug.

[0058] The protruding portion 40 thus forms an annular appendage on the connecting piece 26, which must be protected under various circumstances. In particular, it must be protected during at least one step of the assembly of the Part 26 on the turbomachine, a disassembly step for this part, or a handling / inspection step for the part during its maintenance or initial assembly within the turbomachine. This protection can also be useful during the assembly or inspection of the low-pressure turbine.

[0059] To do this, a protective tooling 50 is provided, forming with the part 26 an assembly 52 specific to the present invention.

[0060] With reference to Figures 4 to 6, the protective tooling 50 has a generally annular shape, centered on axis 2, and split so as to present two free circumferential ends 54, visible in [Fig. 6]. These two ends 54 are preferably spaced apart along the circumferential direction C. The tooling 50, in the general shape of a split or split ring, is preferably produced by additive manufacturing, and it exhibits a certain elasticity, required for its placement on the part 26 to be protected. Indeed, the protective tooling 50 can not only adopt a nominal unassembled configuration, corresponding to the larger representation in [Fig. 6], but also a constrained unassembled configuration, corresponding to the smaller representation in the same [Fig. 6].The transition from one to the other of the two configurations is achieved by elastic deformation of the tooling 50, via the application of a stress 56 on this protective tooling. This stress 56, shown schematically in [Fig. 6], is preferably applied manually by an operator, by exerting circumferential forces on the two free ends 54 to bring these two ends closer together. To facilitate implementation, each of the two free circumferential ends 54 has a gripping element, such as an orifice 58, easily grasped by an operator wishing to manually apply the stress 56.

[0061] The elastic deformation thus induced allows the tool 50 to maintain a general annular shape, but with a reduced radial extent Er, enabling its positioning relative to the part 26 before assembly, as will be described below. The protective tool 50 thus functions in the manner of a circlip.

[0062] The protective tooling 50 has a cross-sectional half-section of constant, or substantially constant, shape and dimensions. By cross-sectional half-section, it is understood that a cross-sectional half-section of the tooling, generally annular in shape, is located locally in a plane of section orthogonal to the circumferential direction C, with respect to the axis 2.

[0063] In each half of the cross-section, a first radially external protective portion 60 is thus provided, intended to axially cover downstream at least a lower portion of the flange 30 of the part. In the assembled state of the tooling shown in [Fig. 5], the first protective portion 60 and the flange 30 preferably have the same, or substantially the same, orientation.

[0064] On the opposite side in the radial direction R, the protective tooling 50 includes a second radially internal protective part 62, intended to cover downstream at least an upper part of the conical part 34 of the part 26. In the assembled state, the second protective part 62 and the conical part 34 which it covers, preferably have the same orientation, or substantially the same orientation, both being of complementary general conical shapes.

[0065] To connect these two parts 60, 62, the tooling 50 includes an intermediate protective portion 64, which defines a housing 66 intended to receive the protruding portion 40 to be protected. The housing 66 is thus open axially / longitudinally upstream, and radially outwards. This housing 66 therefore has a downstream axial bottom 68, as well as an internal radial bottom 70. In the assembled state, the protruding portion 40 occupies the housing 66 of the tooling, these two elements having complementary, or substantially complementary, shapes.

[0066] It is noted that the three aforementioned parts 60, 62, 64 are in fact annular, centered on axis 2, with identical or substantially identical thicknesses.

[0067] The intermediate protective portion 64 has, on the side of the second protective portion 62, a radially outward curved connecting wall 72. This wall 72 delimits a portion of the housing 66, but it also serves to protect the connecting radius 74 between the conical portion 34 and the projecting portion 40 of the part to be protected. Here too, the connecting wall 72 and the connecting radius 74 have complementary shapes. Still in the nominal unassembled configuration, the curved connecting wall 72 extends outward in the radial direction R beyond the internal radial base 70 of the housing 66, which notably allows this housing to be formed. Furthermore, again in this nominal unassembled configuration, the second protective portion 62 extends radially inward beyond the intermediate protective portion 64.

[0068] Finally, the intermediate protective portion 64 has, on the side of the first protective portion 60, a connecting wall 76 extending radially outwards and axially / longitudinally upstream. This wall 76 delimits a portion of the housing 66, but it also serves to protect the connecting radius 78 between the flange 30 and the projecting portion 40 of the part to be protected 26. The connecting wall 76 and the connecting radius 78 also have complementary shapes.

[0069] According to another preferred embodiment shown in [Fig.7], each of the first and second protective parts 60, 62 has an overthickened bearing area 80, for example between 0.1 mm and 0.5 mm, and preferably on the order of 0.2 mm.

[0070] Each bearing area 80 then corresponds to the area intended to be in contact with the corresponding part 30, 34 of the part to be protected 26. Each bearing area on The thickened section 80 results in an adjacent recess, allowing for clearance between the part 26 and its protective tool 50. This accommodates slight differences in shape and / or dimensions that may be encountered on connecting parts 26 from different turbomachines. These two bearing areas 80 are preferably located at the periphery of the protective parts 60 and 62, respectively.

[0071] Whatever the preferred embodiment envisaged, the protective tooling 50 is self-supporting after being assembled on the part to be protected 26, since its retention in place on this part is ensured by its own shape, and more precisely by its cooperation of shape with this part 26.

[0072] Figures 8 and 9 schematically illustrate a method for assembling the protective tooling 50 onto the connecting part 26 of the turbine. This method first comprises a step consisting of moving the tooling 50 from its nominal unassembled configuration shown in [Fig. 8] to its constrained unassembled configuration shown in dashed lines in [Fig. 9]. This step is similar to the operation described above with reference to [Fig. 6], aimed at reducing the overall size of the tooling 50 in the radial direction R by elastically deforming it, preferably manually by pulling on its ends 54. The resulting reduction in diameter allows, in particular, the axial insertion of the tooling 50 upstream until it is in its final axial position relative to the part to be protected 26, or close to this position.Indeed, to achieve the desired axial position, the radial size reduction is carried out so that the curved junction wall 72 has a smaller maximum outside diameter than the minimum inside diameter of the protruding portion 40 to be protected. This facilitates the upstream axial insertion of the tooling 50 into the conical part 34 of the part 26. This axial insertion may also locally require axial deformation of the intermediate protective part 64, near the curved junction wall 76, which is stressed by the support of the protruding portion 40, as shown schematically in [Fig. 9].

[0073] Next, the process is continued by moving the tooling 50 from its unassembled constrained configuration, shown in dashed lines in [Fig. 9], to its assembled configuration on the connecting piece 26, shown in solid lines in the same [Fig. 9]. This transition is easily achieved by progressively releasing the constraint that was applied to hold the tooling 50 in its unassembled constrained configuration. During this release of constraint, the operator guides the tooling as it redeploys radially, resulting in the progressive insertion of the protruding portion 40 into the housing 66 of this tooling.

[0074] In the assembled configuration, the tooling 50 may still exhibit elastic deformation, in that it does not exactly return to its original configuration nominal value mentioned above. This further improves the self-supporting nature of the protective equipment.

[0075] This tooling assembly on the part can be carried out during a maintenance process of the connecting part 26, which requires its extraction from the tur-bomachine, before undergoing a maintenance step such as an inspection, a repair, etc.

[0076] In order to limit the risks of damage to part 26 to be removed from the turbomachine, the assembly of tooling 50 is carried out as soon as possible, as soon as part 26 becomes accessible from the downstream side.

[0077] Next, the following steps are implemented:

[0078] a) a dismantling step of this part 26, requiring the removal of the bolt rings 29 and 33. The tooling installed makes it possible in particular to protect the protruding portion 40 of the part, when loosening the nuts 33 from downstream, which can cause jerks with the bolt loosening tool;

[0079] b) a handling step of part 26, consisting of transporting it from the turbomachine to a maintenance station;

[0080] c) a maintenance step for part 26, of the type mentioned above. Before this maintenance step, tooling 50 can be removed to facilitate this maintenance step;

[0081] d) a handling step of part 26 towards the turbomachine. Before this step, the tooling 50 can be reattached to this part if it was removed in a previous step, in order to limit the risk of damage to the part; and

[0082] e) a step of mounting the part on the turbomachine, also called the reassembly step, after which the tooling 50 can be disassembled. This disassembly is carried out generally by performing the same steps as those used to assemble this tooling, but in reverse order, preferably always manually.

[0083] As mentioned previously, the protective tooling can also be put in place in a modular state, and for the simple inspection of the low-pressure turbine, even if no direct action is envisaged on the part to be protected.

[0084] Various modifications can be made by a person skilled in the art to the invention just described, solely by way of non-limiting examples, and the scope of which is defined by the attached claims.

Claims

Demands

1. Tooling (50) for protecting a part (26) of a turbomachine, the tooling being configured to be arranged on the part at least during one step among a step of mounting the part within the turbomachine, a step of dismantling this part, and a step of handling the part, the tooling being generally annular in shape, split so as to present two free circumferential ends (54), and comprising, in a cross-sectional half: - a first radially external protective part (60); - a second radially internal protective part (62);- an intermediate protective part (64) connecting the first and second parts (60, 62), and defining a housing (66) intended to receive a portion (40) of said part to be protected, projecting radially inwards, the tooling being configured to be brought from a nominal unassembled configuration, to a constrained unassembled configuration obtained by elastic deformation of the tooling, via the application of a stress (56) on the tooling so as to decrease its radial extent, and the tooling also being configured to be brought from the constrained unassembled configuration to a configuration assembled on the part to be protected (26), by releasing said stress (56).;

2. Protective tooling according to claim 1, characterized in that it is self-supporting.

3. Protective tooling according to claim 1 or 2, characterized in that in the nominal unassembled configuration, the intermediate protective part (64) has, on the side of the second radially internal protective part (62), a junction wall (72) convex radially outwards, and extending radially outwards beyond an internal radial bottom (70) of the housing (66) defined by this intermediate protective part (64), and / or in that in the nominal unassembled configuration, the second radially internal protective part (62) extends radially inwards beyond the intermediate protective part (64).

4. Protective tooling according to any one of the preceding claims, characterized in that each of the first and second protective parts (62, 64) has an overthickened bearing area (80).

5. Protective equipment according to any one of the preceding claims preceding, characterized in that each of the two free circumferential ends (54) has a grasping organ (58), preferably an orifice.

6. Assembly (52) comprising a turbomachine part (26), and a protective tooling (50) according to any one of the preceding claims, intended to protect said part (26) at least during one step among a step of mounting the part within the turbomachine, a step of dismantling this part, and a step of handling the part.

7. Assembly according to claim 6, characterized in that the turbomachine part (26) is a connecting part between a turbine rotor (23) and a turbomachine shaft (24), the connecting part (26) comprising: - a mounting flange (30) on the turbine rotor (23), the flange having mounting holes (32) for passage through mounting elements (33); - a generally conical portion (34) extending radially inwards from a radially internal end of the mounting flange (30); and - at a junction zone between the mounting flange (30) and the generally conical portion (34), a portion (40) of said part to be protected, the portion to be protected projecting radially inwards, and preferably also in a longitudinal direction.

8. Assembly according to claim 7, characterized in that the projecting portion to be protected (40) corresponds to a mechanical reinforcement zone (42) of the part, optionally equipped with a balancing system (44).

9. Method of assembling a protective tool (50) according to any one of the preceding claims, on a turbomachine part (26), comprising the following steps: - passing the tool (50) from its nominal unassembled configuration, to its unassembled constrained configuration obtained by elastic deformation of the tool, via the application of the constraint (56) on this tool so as to reduce its radial extent; - passing the tool (50) from its unassembled constrained configuration to its assembled configuration on the part to be protected (26), by releasing said constraint (56), a passage during which a protruding portion to be protected (40) of said part (26) is inserted into the housing (66) defined by the intermediate protective part (64) of the tool.

10. A method for maintaining a turbomachine part (26), comprising the following steps: a) a dismantling step for this part (26); b) a handling step of the part (26), from the turbomachine (1) to a maintenance station; c) a maintenance step for the part (26); d) a step of handling the part (26) towards the turbomachine (1); e) a step of mounting the part (26) on the turbomachine (1); and also comprising the implementation of the method of assembling a protective tooling (50) according to the preceding claim, on said turbomachine part (26), before the implementation of any step among steps a) to e), the method also comprising a disassembly of the tooling (50), after the implementation of said any step or of one of the steps a) to e) which follow it.

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