TOOLS FOR BONDING A PANEL TO A CASING

Abstract

The invention relates to a tool (100) for gluing at least one panel (702), the tool having an annular shape around an axis and comprising at least a first expandable annular element (104) and a second annular element (102) which extend around the axis; the second annular element comprising two annular portions, respectively front and rear, arranged axially one after the other: the front annular portion (2001) being configured to receive at least the expandable element (104) and said at least one panel (702), the expandable element being interposed radially between said second annular element (102) and said at least one panel (702), the rear annular portion (2002) being connected at its axial end opposite to the front annular portion to an annular rim (204) extending radially outwards and comprising an annular face adapted to bear against an annular piece (600) intended to receive the panel (702).Figure for the summary: Fig. 2.

Description

Title of the invention: TOOL FOR BONDING A PANEL TO A CASING Technical field of the invention

[0001] The present invention relates to a tool for bonding a panel to a casing, an assembly comprising at least this tool and a panel, and a method for manufacturing an aircraft turbomachine casing comprising this assembly. Technological background

[0002] Generally speaking, a turbomachine 900, in particular an aircraft turbomachine, as illustrated in [Fig. 1A], comprises from upstream to downstream (i.e. in the direction of flow of the gas flows F), a fan 910, one or more compressors 902 i, 9022, a combustion chamber 904, one or more turbines 906b 9062 and an ejection nozzle 908 for the combustion gases leaving the turbine(s).

[0003] [Fig. 1B] schematically and partially illustrates a fan 910 of a turbomachine. The fan 910 comprises a bladed wheel 912 which is surrounded by a fan casing 600', also called a retention casing due to its function of retaining the blades in the event of their rupture, or in the event of debris entering the fan.

[0004] With reference to [Fig.1C], a fan casing 600', and more generally a casing, typically comprises an annular casing 602, which may be, for example and in a non-limiting manner, made of metallic material or of a composite material from woven fibers embedded in a polymeric resin. Preferably, the annular casing is made of a composite material. This annular casing 602 has an axis of revolution A and extends around the fan blades 912 of the turbomachine. The casing 600' comprises an annular fixing flange 604i, 6042 at each of the axial ends of the annular casing 602. These flanges 604i, 6042 are used to fix the casing 600' to annular walls of a nacelle which surrounds the turbomachine to form an aircraft propulsion assembly.

[0005] The casing 600' may be connected by the flanges 604b 6042 on the one hand to an air inlet sleeve 4a located upstream of the fan casing 600', and on the other hand, to an intermediate casing shroud 4b located downstream of the fan casing 600', as illustrated in [Fig.lD]. The fan casing 600' also comprises upstream acoustic panels 6 and downstream acoustic panels 8.

[0006] Still with reference to [Fig.lD], an abradable annular cartridge 700 can be positioned on an internal annular surface S602 of the casing 602 of the housing 600', between the upstream acoustic panels 6 and the downstream acoustic panels 8. This Abradable cartridge 700 may comprise an annular layer 704 of abradable material and an annular panel or support 702 supporting the annular layer 704, the annular panel 702 being fixed to the casing 602. This annular abradable layer 704 is intended to wear in a controlled manner during operation. As for the annular panel 702, it may, for example, be solid or have a honeycomb structure.

[0007] In addition to the retention function, the casing 600' is further designed to: - ensure mechanical continuity (of forces and moments) between the air inlet sleeve 4a and the intermediate casing shell 4b; - allow the fixing of the panels of the abradable annular cartridge 700, the upstream acoustic panels 6 and the downstream acoustic panels 8, thus ensuring continuity of the aerodynamic vein; - allow the attachment of equipment and supports known per se, in particular inside the nacelle; - meet regulatory specifications for fire and leaks; - allow continuity of electric current for lightning resistance, etc.

[0008] The casing 602 of the housing 600' and the annular cartridge 700 are separate parts which are manufactured separately and then assembled in an assembly step in which the annular panel 702 is first fixed to the annular casing 602 and then the abradable annular layer 704 is bonded to the annular panel 702.

[0009] It is known in the state of the art to assemble the annular casing 602 of the casing 600' and the annular panel 702 by gluing.

[0010] In operation, the axis of revolution A of the casing is generally horizontal. However, for assembly, the casing 600' is arranged on one of its flanges 604i, 6042 so that its axis of revolution A is vertical. Then, one or more layers of adhesive (such as for example Redux® from Hexcel Composites) are deposited either on a surface S702 of the panel 702 of the abradable annular cartridge 700, intended to come into contact with the internal annular surface S602 of the annular casing 602 of the casing, or on the internal surface S602 of the annular casing 602 of the casing. The panel is then arranged inside the casing 602 of the casing 600' and held at a predefined location using pins. So-called technical fabrics such as, for example, and in a non-limiting manner, delaminating, draining, tear-off fabrics, and a waterproof tarpaulin with seal are affixed to the assembly formed by the envelope 602 and the panel 702.

[0011] The assembly formed by the panel 702 and the annular envelope 602 is then placed in an autoclave for the polymerization of this glue. The abradable annular layer 704 is finally secured by gluing to the panel 702.

[0012] The internal surface S6o2 of the envelope 602 is pierced after the gluing of the panel 702 of the abradable support cartridge 700. This drilling allows the fixing of the upstream 6 and downstream 8 acoustic panels.

[0013] This assembly method, described above and which requires the use of tools comprising at least technical fabrics and the pins, can have several drawbacks, including: - a significant implementation time due to the installation of technical fabrics; - a risk of leakage of the tarpaulin during the autoclave cooking cycle (poor application of the seal, presence of thermocouples, micro-perforation of the waterproof tarpaulin, etc.) which could generate non-conformities; - an environmental problem due to the high production of waste after each cooking cycle: the fabrics are single-use, which can lead to the production of several tons of waste per year; - a high production cost due to the use of a large number of technical fabrics.

[0014] It may thus be desirable to provide bonding tools which make it possible to overcome at least some of the aforementioned problems and constraints. Summary of the invention

[0015] There is therefore proposed a tool for bonding at least one annular panel to an internal surface of an annular part, the tool having an annular shape around an axis and comprising at least: - a first annular element which extends around the axis and which is expandable so that its radial dimension or thickness can be modified; and - a second annular element which extends around the axis and which comprises two annular portions, respectively front and rear, arranged axially one after the other: • the front annular portion comprising an annular housing opening radially outwards and configured to receive at least the expandable element and said at least one annular panel, the expandable element being intended to be interposed radially between said second annular element and said at least one annular panel, • the rear annular portion being connected at its axial end opposite the front annular portion to an annular rim which extends radially outwards and which comprises an annular face oriented towards the side of the front annular portion and capable of coming to bear on the annular part.

[0016] By expandable element is meant an element which can increase in volume or which is inflatable. In particular, the expansion makes it possible to modify the radial dimension or thickness of the element and therefore to increase and / or decrease its internal diameter and / or its external diameter.

[0017] When bonding the annular panel to an internal surface of the annular part, preferably an annular casing for an aircraft turbomachine, the panel is arranged in the annular housing of the first portion of the second annular element with the expandable element deflated, so that the expandable element is interposed between the panel and the second annular element.

[0018] The glue is then deposited at a predefined location on the internal surface of the envelope of the annular part and / or on an external surface of the panel intended to be glued at the predefined location.

[0019] The assembly comprising the tooling and the panel is then inserted inside the annular part, the rear annular portion of the second element bearing on the annular part. The panel is interposed between the expandable element and the internal surface of the envelope of the annular part. The expandable element is then inflated, which will exert pressure or stress on the panel so as to fix it on the internal surface of the envelope of the annular part at the predefined location.

[0020] Thus, thanks to the invention, it is possible to easily assemble, for example, a casing of an aircraft turbomachine by improving the positioning of a panel at the predefined location of the internal surface of the casing envelope thanks to the second annular element while ensuring that the panel is held under stress on the internal surface of the casing using the expandable element. This makes it possible to avoid or reduce manufacturing defects linked to poor positioning of the panel and / or to degradation of the technical fabrics described above.

[0021] The invention also allows a saving in time. Indeed, still with reference to the casing, it is no longer necessary to prepare technical fabrics as described above and to affix them to the assembly formed by the casing and the panel. There is therefore elimination of at least one step in the mounting or assembly of the casing and consequently, a saving in time.

[0022] The invention also makes it possible to reduce both the ecological footprint relating to the manufacture or assembly of annular parts, preferably casings, and the manufacturing cost of the annular parts. Indeed, in the case where the annular part is a casing, the tooling can be used over several production cycles and it is no longer necessary to use single-use fabrics for bonding. Waste production is therefore enormously reduced or eliminated.

[0023] A tool according to the invention may further comprise one or more of the following optional characteristics, in any technically possible combination: - the first annular element is inflatable, and is in particular an inflatable annular bladder; - the rear annular wall has an external diameter which is greater than the diameter of a bottom of said housing and which is intended to be greater than or equal to an external diameter of said at least one annular panel; - the annular rim comprises fixing means capable of fixing the tooling to said annular part intended to receive the annular panel; - the front annular portion includes tabs for holding the panel in the annular housing; - the rear annular portion comprises gripping means located on its annular edge; - the expandable element is configured to exert a pressure in the radial direction between 0.1bar and 3bars; - the tooling comprises at least one device for actuating the expansion of the expandable element;

[0024] The invention also relates to a first assembly comprising at least one tool according to the invention and at least one annular panel, said annular panel being arranged in the annular housing of the front annular portion.

[0025] The invention further relates to a second assembly comprising: - a tool according to the invention equipped with at least one annular panel arranged in the annular housing of the front annular portion; and - an annular part intended to receive the annular panel; the tooling equipped with the annular panel being inserted into the annular part intended to receive the annular panel.

[0026] A first or a second assembly according to the invention may further comprise the following optional characteristic, according to any technically possible combination: - the part is an annular casing of an aircraft turbomachine.

[0027] The invention also relates to a method for manufacturing an annular part, the part comprising an annular envelope having an axis of revolution and comprising at least one internal surface intended to receive at least one annular panel, the method comprising at least one step of bonding the annular panel to the internal surface by means of a tool according to the invention, the bonding step comprising at least: - the depositing of an adhesive on an external surface of the annular panel intended to be glued to the internal surface of the annular envelope and / or to said internal surface; - insertion of the tool equipped with the annular panel into the part; - expansion of the expandable element; - compression bonding of the annular panel to the internal surface of the part envelope.

[0028] A method according to the invention may further comprise at least the following optional characteristics, in any technically possible combination: - the bonding of the annular panel comprises at least the arrangement in an autoclave of the assembly formed by the part and the annular panel to polymerize the glue; - the part is an annular casing of an aircraft turbomachine. Brief description of the figures

[0029] The invention will be better understood with the aid of the following description, given solely by way of example and with reference to the appended drawings in which: - [Fig.1A] is a schematic representation of a simplified view of a turbomachine according to the prior art, - [Fig.lB] is a schematic representation of an axial and partial sectional view of a fan of an aircraft turbomachine, according to the prior art, - [Fig.lC] is a schematic representation of a perspective view of a fan casing, according to the prior art; - [Fig.lD] is a schematic representation of a partial axial sectional view of a fan casing, according to the prior art; - [Fig.2] is a schematic representation of a perspective view of a tool according to the invention; - [Fig.3] is a schematic representation of a perspective view of a portion of the second annular element of the tooling of [Fig.2]; - [Fig.4] is a schematic representation of an axial sectional view of a first assembly comprising the tooling of [Fig.2] equipped with a panel; - [Fig.5] is a schematic representation of an axial sectional view of a second assembly comprising the first assembly of [Fig.4] inserted inside an annular part; - [Fig.6] is a schematic representation of a method of bonding a panel to the internal surface of an annular part according to the invention; - [Fig.7] is a schematic representation of a method of inserting the first assembly of [Fig.4] into an annular part; - [Fig.8A] is a schematic representation of a perspective view of the positioning of the panel on the tooling according to the invention; - [Fig.8B] is a schematic representation of a perspective view of the first assembly of [Fig.4] according to the invention; - [Fig.8C] is a schematic representation of a perspective view of inserting the first assembly of [Fig.4] inside the annular part; Detailed description of the invention

[0030] Although in the examples which will be described below, for illustrative purposes, the parts are annular parts which have an axis of revolution and comprise annular surfaces, those skilled in the art will understand that these examples are in no way limiting. The invention can be applied to the bonding of parts, of different shapes having or not having an axis of revolution, an annular or linear body, a flat or annular or curved, or complex surface.

[0031] By convention, in the description below, the term "axial" qualifies the orientation of structural elements extending in the direction of an axis. This axis corresponds substantially to an axis of rotation or revolution. The term "radial" qualifies an orientation of structural elements extending in a direction perpendicular to the axis of rotation or revolution. The terms "inner" and "outer", "front" and "rear", "inner" and "outer" are used with reference to a positioning relative to the axis of rotation or revolution. Thus, a structural element extending along the axis of rotation or revolution has an inner face facing the longitudinal axis and an outer surface, opposite its inner surface.Similarly, a portion of a structural element that extends radially toward the axis of rotation or revolution will be considered a front portion, and a portion of the same structural element that extends radially away from the axis of rotation or revolution will be considered a rear portion.

[0032] [Fig.2] illustrates an example of tooling according to the invention.

[0033] The tool 100 has an annular shape around a revolution axis Ao and comprises a first 104 and a second 102 annular element which extend around the axis Ao, the first annular element 104 enveloping a portion of the second annular element 102.

[0034] The first annular element 104 is expandable so that its radial dimension or thickness can be modified.

[0035] At least one device may also be provided in the tool 100 for actuating the expansion of the expandable annular element 104.

[0036] [Fig. 3] illustrates a perspective view of a portion of the second annular element 102.

[0037] The second annular element 102 comprises two annular portions, respectively front 200i and rear 2002. The front and rear annular portions 200i, 2002 are arranged axially one after the other.

[0038] The front annular portion 200i comprises an annular housing 206 which opens radially inward. The annular housing is configured to receive the expandable member 104.

[0039] The annular housing 102 may be configured to further receive at least one annular panel 702. In this configuration, the expandable element is interposed radially between the second annular element 102 and the annular panel 702. For example, and in a non-limiting manner, the panel is a support for a layer of abradable material 704.

[0040] The front annular portion 200i further comprises lower 202i and upper 2022 retaining tabs of the annular panel 702 in the annular housing 206. The upper retaining tab 2022 being axially located above the lower retaining tab 202h

[0041] In another variant (not shown), the axial width of the housing is slidably adjusted so that the axial width of the housing is adapted to receive expandable elements and panels of different axial widths. In this configuration, the front portion of the second annular element may comprise a sliding mechanism which allows the lower retaining tab 202i to be moved in the axial direction towards the upper retaining tab 2022 so as to reduce or increase the axial width of the housing.

[0042] Still with reference to [Fig. 3], the rear annular portion 2002 of the second annular element 102 comprises at least one axial end E204 opposite the front annular portion 200i and an annular rim 204, the axial end E204 being connected to the annular rim 204.

[0043] The annular rim 204 extends radially outwards and comprises an annular face F204 oriented towards the side of the front annular portion 200i and capable of coming to bear on an annular part 600, preferably a casing 600', intended to receive the panel.

[0044] The annular rim 204 may further comprise fixing means on its annular face F204 capable of fixing the tooling to the annular part 600. In the case where the annular part 600 is a casing 600', the annular rim bears on the casing 600' at one of the flanges 604b 6042 in order to secure the fixing of the tooling 100 on the casing 600', as illustrated in [Fig.5] described in the remainder of the description.

[0045] The rear annular portion 2002 has an external diameter Dext which is greater than the diameter DL of a bottom of the housing 206 of the front annular portion and which is intended to be greater than or equal to an external diameter Dp of the annular panel 702, as illustrated for example in [Fig.4] described in the remainder of the description.

[0046] The rear annular portion 2002 may further comprise gripping means 208 located on its annular rim 204 as illustrated for example in FIGS. 2 or 3.

[0047] Preferably, the expandable element 104 is configured to exert a pressure in the radial direction of between 0.1 bar and 3 bars. For example, and in a non-limiting manner, the first annular element is an elastomer or silicone bladder.

[0048] Preferably, the second annular element is made of rigid material. For example and in a non-limiting manner, the second annular element may be made of aluminum, steel or composite material.

[0049] The invention relates to The invention also relates to a first tool assembly.

[0050] [Fig.4] represents a sectional view of a tool assembly according to the invention. The assembly comprises a tool 100 described above and at least one panel 702. The annular panel 702 is arranged in the annular housing 206 of the front annular portion 200i. The expandable element 104 of the tool is interposed radially between the second annular element 102 and the annular panel 702.

[0051] In this example, the external diameter Dext of the rear portion 2002 is equal to the external diameter Dp of the annular panel 702.

[0052] The invention also relates to a second assembly.

[0053] [Fig.5] illustrates an example of the second assembly according to the invention. This assembly comprises at least the first assembly as shown in [Fig.4], i.e. a tool 100 equipped with an annular panel 702.

[0054] The second assembly further comprises an annular part 600, preferably a casing 600', the tooling 100 equipped with the annular panel 702 being inserted into the annular part 600. The first assembly is inserted into the annular part 600 so that the axis Ao of the tooling 100 coincides with the axis of revolution A of the annular part 600.

[0055] In this second assembly, the annular panel 702 is interposed between the expandable element 104 of the tool 100 and the internal surface of the annular part 600. In the case where the annular part 600 is a casing 600', the rear annular portion 2002 and its annular rim 204 bear respectively on the internal surface and one 604i of the flanges 604i, 6042 of the casing 600'.

[0056] The invention also relates to a method for manufacturing an annular part 600, preferably an annular casing 600' for an aircraft turbomachine, the annular part 600 comprising an annular casing 602 having an axis of revolution A and comprising at least one internal surface S602 intended to receive at least one annular panel 702.

[0057] As illustrated in [Fig.6], the manufacturing method at least one step of gluing 400 of the annular panel 702 on the internal surface S6o2 by means of the tooling 100 described above.

[0058] The bonding step 400 comprises at least: - the insertion 500 of the tooling equipped with the annular panel 702 into the annular part 600; - the expansion 502 of the expandable element 104; - the gluing 504 by compression of the annular panel 702 on the internal surface of the annular part 600.

[0059] With reference to Figures 7 to 8C, the insertion 500 of the equipped tool 100 into the annular part 600 will now be described in detail.

[0060] The insertion 500 of the tooling 100 equipped with the annular panel 702 comprises at least the arrangement 800 of the annular panel 702 in the annular housing 206 of the first portion 200i of the second annular element 102 with the expandable element 104 deflated, as illustrated in [Fig.8A], to form the tooling equipped with the panel as illustrated in [Fig.8B].

[0061] The glue is then deposited 802 at the predefined location of the internal surface S602 of the envelope 602 of the annular part 600 and / or on an external surface S702 of the panel 702 intended to be glued at the predefined location.

[0062] After the glue has been deposited, the assembly formed by the tool 100 and the annular panel 702 is guided 804, as illustrated in [Fig.8C], using the gripping means 208 of the tool inside the casing so that the external surface S702 of the annular panel 702 is opposite the predefined location.

[0063] The expandable element is then inflated to fix 806 the panel 702 on the internal surface of the envelope 602 of the annular part 600.

[0064] The bonding 504 of the panel 702 after its fixing on the internal surface of the annular part 600 comprises at least the arrangement in an autoclave of the assembly formed by the annular part 600 and the panel 702 in order to polymerize the glue. The polymerization temperature can vary between 80°C and 200°C for a duration of between 1 h and 4 h, depending on the type of glue used. For example, and in a non-limiting manner, the glue can be of the epoxy, bismaleimide or polyimide type.

[0065] Advantageously, a person skilled in the art will understand that the tooling of the present invention makes it possible to facilitate the bonding of a panel to the internal surface of the envelope of an annular part, preferably a casing: - by improving the positioning of the panel at the predefined location thanks to the housing and the retaining tabs of the front portion of the second annular element and the means of fixing the rear portion of the second annular element, and - by ensuring that the panel is held under stress on the internal surface of the annular part using the expanding element. This helps to avoid or reduce manufacturing defects linked to poor positioning of the panel and / or degradation of the technical fabrics described above.

[0066] The invention also allows a saving in time. Indeed, in the case where the annular part 600 is a casing 600' for example, it is no longer necessary to prepare technical fabrics and to affix them to the assembly formed by the casing 600' and the annular panel 702. There is therefore elimination of at least one step in the mounting or assembly of the casing and consequently, a saving in time.

[0067] The invention also makes it possible to reduce the ecological footprint relating to the manufacture or assembly of annular parts, for example casings. Indeed, the tooling can be used over several production cycles and it is no longer necessary to use single-use fabrics. Waste production is therefore enormously reduced or eliminated.

[0068] The invention also makes it possible to reduce the manufacturing cost of an annular part, preferably a casing, since it is no longer necessary to use fabrics for bonding, for example.

[0069] .

Claims

Claims

1. Tool (100) for bonding at least one annular panel (702) to an internal surface of an annular part (600), characterized in that the tool has an annular shape around an axis and comprises at least: - a first annular element (104) which extends around the axis and which is expandable so that its radial dimension or thickness can be modified; and - a second annular element (102) which extends around the axis and which comprises two annular portions, respectively front and rear, arranged axially one after the other; • the front annular portion (2000) comprising an annular housing (206) opening radially outwards and configured to receive at least the expandable element (104) and said at least one annular panel (702), the expandable element being intended to be interposed radially between said second annular element (102) and said at least one annular panel (702);• the rear annular portion (2002) being connected at its axial end opposite the front annular portion to an annular rim (204) which extends radially outwards and which comprises an annular face oriented towards the side of the front annular portion and capable of coming to bear on the annular part (600).;

2. The bonding tool (100) of claim 1, wherein the first annular element is inflatable, and is in particular an inflatable annular bladder.

3. Bonding tool (100) according to claim 1 or 2, wherein the rear annular wall has an external diameter which is greater than the diameter of a bottom of said housing and which is intended to be greater than or equal to an external diameter of said at least one panel.

4. Bonding tool (100) according to any one of claims 1 to 3, in which the annular rim (204) comprises means of fixing capable of fixing the tooling to said annular part (600).

5. Bonding tool (100) according to any one of claims 1 to 4, in which the front annular portion (2000) comprises retaining tabs (202b 2022) of the panel (702) in the annular housing (206).

6. Bonding tool (100) according to any one of claims 1 to 5, in which the rear annular portion (2002) comprises gripping means (208) located on its annular rim (204).

7. Bonding tool (100) according to any one of claims 1 to 6, wherein the expandable element (104) is configured to exert a pressure in the radial direction of between 0.1 bar and 3 bars.

8. A bonding tool (100) according to any one of claims 1 to 7, wherein the tool (100) comprises at least one device for actuating the expansion of the expandable element (104).

9. Assembly comprising a tool (100) according to one of the preceding claims and at least one annular panel (702), said annular panel (702) being arranged in the annular housing (206) of the front annular portion (200i).

10. Assembly comprising: - a tool (100) according to one of claims 1 to 8 equipped with at least one annular panel (702) arranged in the annular housing (206) of the front annular portion (2000; and - an annular part (600) intended to receive the panel; the tool (100) equipped with the annular panel (702) being inserted into the annular part (600) intended to receive the panel.

11. An assembly according to claim 9 or 10, wherein the part is an annular casing of an aircraft turbomachine.

12. A method of manufacturing an annular part (600), the part (600) comprising an annular envelope (602) having an axis of revolution (A) and comprising at least one internal surface (S602) intended to receive at least one panel (702), the method comprising at least one step of gluing (400) the panel (702) onto the internal surface (S602) by means of a tool (100) according to any one of claims 1 to 8, the gluing step (400) comprising at least: - the deposition (500) of an adhesive on an external surface (S702) of the annular panel (702) intended to be glued to the internal surface (S6o2) of the annular envelope (602) and / or to said internal surface (S6o2); - the insertion (500) of the tooling equipped with the annular panel (702) into the part (600); - the expansion (502) of the expandable element (104); - the gluing (504) by compression of the annular panel (702) onto the internal surface (S602) of the envelope (602) of the part (600).

13. Method according to the preceding claim, in which the bonding (504) of the annular panel (702) comprises at least the arrangement in an autoclave of the assembly formed by the part (600) and the annular panel (702) to polymerize the glue.

14. A method according to claim 12 or 13, wherein the part is an annular casing of an aircraft turbomachine.

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