Mold intended for use in the manufacture of a blower housing and method for manufacturing a blower housing

Abstract

Mold intended for use in the manufacture of a blower housing and method for manufacturing a blower housing The present invention relates to a mold (400) intended for use in the manufacture of a blower housing (10) made of composite material, the mold comprising: - a mandrel (431) on which a fibrous preform (410) of blower housing is intended to be wound, the mandrel comprising an annular wall whose outer surface profile corresponds to that of the inner surface (14) of the housing to be manufactured and two side flanges (430) whose profiles correspond to those of flanges (12, 13) of the housing to be manufactured; - a plurality of angular sectors intended to close the mold and to compact the fibrous preform wound on the mandrel, the mold further comprising a ring-shaped profile (440) intended to be placed between the fibrous preform wound on the mandrel and the angular sectors of the counter-mold.Figure for the summary: Fig. 4.

Description

Title of the invention: Mold for use in manufacturing a fan casing and method of manufacturing a fan casing Technical field

[0001] The present invention relates to the general field of the manufacture of rotating parts such as gas turbine casings, and more particularly gas turbine fan casings for aeronautical engines. Prior art

[0002] In the aeronautical field, there is an attempt to reduce the mass of engine components while maintaining their mechanical properties at a high level. For example, in an aeronautical turbomachine, the fan casing defining the contour of the engine's air inlet duct and inside which the rotor supporting the fan blades is housed is now made of composite material.

[0003] The manufacture of a fan casing in composite material begins with the installation by winding a fiber reinforcement onto a mandrel whose profile matches that of the casing to be produced.

[0004] The fibrous reinforcement can be produced, for example, by three-dimensional or multi-layer weaving as described in US patent 8,322,971. This fibrous reinforcement is shaped to constitute a single piece comprising a tubular portion and folded portions intended to form the upstream and downstream flanges of the fan casing.

[0005] The mandrel, the profile of which matches that of the casing to be produced, may comprise an annular wall in the form of a barrel forming a support intended to receive the tubular portion of the fiber preform, and two lateral flanges forming a support intended to receive the folded portions of the preform which are intended to form the upstream and downstream flanges of the fan casing.

[0006] Manufacturing continues by depositing a counter-mold on the fiber preform to close the mold and then by densifying the fiber preform with a polymer matrix which consists of impregnating the preform with a resin and polymerizing the latter to obtain the final part.

[0007] The manufacturing relates more particularly to the manufacturing method where the impregnation of the fiber preform is carried out by the injection molding process called RTM (for "Resin Transfer Molding"). According to this process, once the counter-mold, the shape of which corresponds to the part of revolution that one wishes to obtain, is placed on the fiber preform, the resin is injected under controlled pressure and temperature at inside the mold. Once the resin is injected, it is polymerized by heating the mold and after injection and polymerization, the final part is demolded and then trimmed to remove excess resin and the chamfers are machined to obtain the desired final part, for example a fan casing.

[0008] As the preform is expanded at the time of its winding onto the mandrel, that is to say that it has an excess thickness compared to the theoretical thickness of the final part, the closing of the mold also ensures the function of definitive compaction of the preform to bring it to its final thickness.

[0009] [Fig.1A] illustrates an RTM injection mold 300 composed of a drum or mandrel 331 on which a fiber preform 310 is wound and a counter-mold formed by a plurality of angular sectors 320. The mold is closed by the angular sectors 320 which ensure the compaction of the preform.

[0010] As illustrated in [Fig.lB], the counter-mold may be formed by a plurality of first angular sectors 321 (in [Fig.lB], only one angular sector is visible) intended to ensure the compaction of the tubular portion 314 of the preform 310. These first angular sectors 321 are intended to enclose the tubular portion 314 of the preform between said first angular sectors 321 and the annular wall 333 in the shape of the barrel of the mandrel 331, these first angular sectors 321 being able to be called barrel angular sectors. The counter-mold may furthermore be formed by a plurality of second angular sectors 322 and a plurality of third angular sectors 323 intended to respectively ensure the compaction of the folded-down portions 311, 312 of the preform intended to form the lateral flanges, for example upstream and downstream of the fan casing.These second and third angular sectors 322, 323 are intended to enclose the folded portions 311, 312 of the preform 310 between said second and third angular sectors 322, 323 and the lateral flanges 330, 332 of the mandrel 331, these second angular sectors 322, 323 being able to be called angular flange sectors.

[0011] Closing the mold by such angular sectors can prove to be a delicate operation. Indeed, as illustrated in [Fig.2A], one first places one sector out of two which each locally compacts the fiber preform. The fiber preform 310 has bulges or folds 31 in the vicinity of the ends of each angular sector 320 because it is no longer compacted. The closing of the mold continues by positioning the remaining angular sectors between the sectors already positioned as illustrated in FIGS. 2B and 2C. When these sectors are put in place, the bulges 31 are pushed back against the edges of the sectors already positioned because the preform is driven out of the middle of the sector by the compaction. In addition, the shape of the sectors and the direction of closing of the mold mean that there remains a space between the sectors until the last moment of closing the mold. A part of the blisters 31 then enters this space to be finally pinched between the edges of the adjacent sectors as shown in [Fig.2C]. The fibers of the preform thus pinched lead to the creation of defects called "pinch fibers" on the finished part. Indeed, these pinched fibers are found on the finished part, that is to say after injection of the resin into the preform and transformation of the latter into a matrix, in the form of blisters present on the external surface of the part. In order to have a satisfactory surface condition, the blisters are sanded, which causes a break in the continuity of the wires or strands in the part and, consequently, a significant reduction in the mechanical properties of the latter.

[0012] This pinching phenomenon can appear both at the level of the tubular portion of the fibrous reinforcement and at the level of the folded portions intended to form the upstream and downstream flanges of the fan casing.

[0013] In patent FR3100738 filed by the applicant, a plurality of sheets is used to protect the tubular part of the fiber preform from possible pinching between two adjacent angular sectors at the junction zone between two angular sectors. The invention nevertheless focuses on the tubular part of the preform and not the folded portions intended to form the flanges of the fan casing. The use of several sheets causes indentations, an imprint left by each sheet on the final injected part, which remains on the part for life. If these indentations are tolerated on the tubular part of the fan casing, they are unacceptable on the flanges of the fan casing. Statement of the invention

[0014] The invention aims in particular to overcome at least in part one of these drawbacks and relates, according to a first aspect, to a mold intended to be used for the manufacture of a fan casing, for example a gas turbine casing, made of composite material, the mold comprising: - a mandrel on which a fibrous fan casing preform is intended to be wound, the mandrel comprising an annular wall whose outer surface profile corresponds to that of the inner surface of the casing to be manufactured and two lateral flanges whose profiles correspond to those of the flanges of the casing to be manufactured; - a plurality of angular counter-mold sectors intended to close the mold and compact the fiber preform wound on the mandrel, the mold comprising a ring-shaped profile intended to be placed between the fiber preform wound on the mandrel and the angular counter-mold sectors.

[0015] Thanks to the ring shape of the profile, it is possible to protect at least part of the preform over the entire circumference of this part (this part being able to be one of the folded portions of the preform and / or the annular wall), that is to say over its entire circumference. around, for example 360° without interruption.

[0016] Unlike the use of several sheets of the prior art, the ring-shaped profile makes it possible to avoid the formation of folds which could be created between two adjacent sheets. Furthermore, the ring-shaped profile, which can extend over 360° on the preform, without forming a break unlike the use of several sheets, makes it possible to avoid the formation of indentations. This is particularly advantageous when the profile is used to protect the folded portions of the preform intended to form the flanges of the casing to be manufactured. Finally, thanks to the ring-shaped profile, it is no longer necessary to successively place each sheet between two angular sectors. The ring-shaped profile can be placed in one go before integrating the angular sectors.

[0017] According to other characteristics of the invention, the mold of the invention comprises one or more of the following optional characteristics considered alone or in all possible combinations.

[0018] The profile is formed in a single piece.

[0019] The fiber preform intended to be wound on the mandrel comprises an annular wall intended to form an annular wall of the casing to be manufactured and two folded portions intended to form flanges of the casing to be manufactured and the profile is configured to extend over the circumference of a part of one of the two folded portions of the preform intended to form the flanges of the casing to be manufactured and / or over the circumference of at least a part of the annular wall of the preform intended to form the annular wall of the casing to be manufactured.

[0020] The profile comprises a portion configured to extend around the circumference of a portion of one of the two folded portions of the fiber preform and a portion configured to extend around the circumference of a portion of the annular wall of the fiber preform.

[0021] The profile comprises a cross-section having two legs forming an angle, the first leg of which corresponds to the portion configured to extend over the circumference of a part of one of the two folded portions of the fiber preform intended to form the flanges of the casing and the second leg of which corresponds to the portion configured to extend over the circumference of a part of the annular wall of the fiber preform.

[0022] The profile is made of woven or metallic material. The woven or metallic material withstands the injection step. The profile can be removed at the end of the casing manufacturing process and in particular after the injection step, which eliminates the risks of fiber disorganization of the prior art. The metallic material is particularly preferred because it has demonstrated the best performance results.

[0023] The profile has a thickness greater than 0.2 mm. When the profile has a thickness greater than 0.2 mm, it has the advantage of being reusable. Indeed, with a thickness of less than 0.2 mm, the profile can undergo deformations during the manufacturing process of the fan casing and therefore cannot be reused. The profile can therefore be designed in a more economical / ecological approach by providing a thicker and reusable profile after each injection.

[0024] The profile has a thickness between 0.2 mm and 1 mm. This range of values ​​demonstrates the best compromise for having a profile that is reusable but remains flexible enough to be able to integrate it into the mold, that is to say the best compromise of durability and flexibility.

[0025] According to another aspect the invention relates to a method of closing an injection mold as previously described, the method comprising the steps: - watertight assembly of the angular counter-mold sectors on the mold mandrel; and - placement of the profile between the fiber preform wound on the mandrel and the angular sectors of the counter-mold.

[0026] According to another aspect the invention relates to a method of manufacturing a gas turbine fan casing made of composite material comprising:

[0027] - winding a fiber preform onto the mandrel of a mold such as pre previously described;

[0028] - closing the mold according to the mold closing method as pre previously described;

[0029] - injecting a resin into the mold; and

[0030] - demolding the fan casing. Brief description of the drawings

[0031] [Fig.lA] [Fig.lA] is a schematic perspective view of an injection mold according to the prior art.

[0032] [Fig.lB] [Fig.lB] is a cross-sectional view of a closed mold according to the prior art.

[0033] [Fig.2A] [Fig.2A] is a partial radial sectional view showing a closing step of the mold of [Fig.1A].

[0034] [Fig.2B] [Fig.2B] is a partial radial sectional view showing another step of closing the mold of [Fig.1A].

[0035] [Fig.2C] [Fig.2C] is a partial radial sectional view showing another step of closing the mold of [Fig.1A].

[0036] [Fig.3] [Fig.3] is a schematic perspective view of a composite material fan casing.

[0037] [Fig.4] [Fig.4] is a cross-sectional view of a closed mold according to the invention.

[0038] [Fig.5] [Fig.5] is a partial view of the closed mold according to the invention.

[0039] [Fig.6] [Fig.6] represents a profile according to the invention.

[0040] [Fig.7] [Fig.7] is an enlarged view of the profile of [Fig.6]. Description of the embodiments

[0041] In the remainder of the description of the applicator according to the invention, the same numerical references designate the same elements.

[0042] The invention will be described below in the context of its application to the manufacture of a fan casing for an aeronautical gas turbine engine.

[0043] [Fig. 3] represents a perspective view of a fan casing 10 which can be manufactured using a mold and a method according to the invention. Such a casing is centered on a longitudinal axis XX and comprises an annular wall 11 delimited upstream by an upstream flange 12 and downstream by a downstream flange 13 (upstream and downstream being defined relative to the direction of flow of the gas flow in the gas turbine). The internal surface 14 of the annular wall 11 is intended to delimit the air inlet vein in the gas turbine. The annular wall 11 of the casing can thus be delimited by two external flanges 12, 14, for example two lateral flanges 12, 14.

[0044] [Fig. 4] illustrates, schematically and partially, a mold 400 according to the invention, when it is closed.

[0045] Such a mold 400 can be used for impregnation by a process of the RTM type (Resin Transfer Molding) of a fiber preform 410 in order to manufacture a fan casing 10 such as that presented in [Fig. 3].

[0046] The fiber preform 410 may comprise an annular wall 414 intended to form the annular wall 11 of the fan casing to be manufactured. The annular wall 414 may be delimited by two folded portions 411, 412 intended to form respectively the upstream flange 12 and the downstream flange 13 of the fan casing 10 to be manufactured. For example, the first folded portion 411 of the preform 410 is intended to form the upstream flange 12 of the fan casing and the second folded portion 412 of the preform 410 is intended to form the downstream flange 13 of the fan casing. Each of the two folded portions 411, 412 of the preform 410 may, respectively, extend radially from an edge of the annular wall 414 of the preform 410.

[0047] The fiber preform 410 can be made by three-dimensional weaving of fibers, for example carbon, glass, aramid or ceramic, and the impregnation matrix can be made of polymer, for example epoxide, bismaleimide or polyimide.

[0048] The mold 400 may be rotatably mounted on a drive axis (not shown) centered on the axis XX, and may include a mandrel 431. The mandrel 431 may comprise an annular wall 433 taking the form of a barrel on which the fiber preform 410 is intended to be wound, in particular the part of the fiber preform 410 intended to form the annular wall of the fan casing, for example the annular wall 414 of the fiber preform, and two lateral flanges (or side walls) 430, 432. The mandrel 431 may be held on its drive axis by means of spokes not shown.

[0049] The lateral flanges 430, 432 (or side walls) of the mandrel 431 form a support intended to receive the folded portions 411, 412 of the preform 410, when the preform 410 is wound onto the mandrel 431. For example, the first lateral flange 430 forms a support intended to receive the first folded portion 411 of the preform intended to form the upstream flange 12 of the casing to be manufactured and the second lateral flange 432 forms a support intended to receive the second folded portion 412 of the preform intended to form the downstream flange 13 of the casing to be manufactured. The lateral flanges 430, 432 may extend radially from an edge of the annular wall 433 of the mandrel 431

[0050] The mold 400 may also comprise a counter-mold 420. The counter-mold 420 may comprise a plurality of angular sectors 421, 422, 423 which may be intended to close the mold and to compact the fiber preform wound on the mandrel. For example, the angular sectors 421, 422, 423 may be intended to be assembled in a sealed manner on the mandrel 433.

[0051] As illustrated in [Fig. 4], the counter-mold 420 may comprise a plurality of first angular sectors 421 ensuring the compaction of the annular wall 414 of the preform 410, a plurality of second angular sectors 422 ensuring the compaction of the first folded portion 411 of the preform 410 and a plurality of third angular sectors 423 ensuring the compaction of the second folded portion 412 of the preform 410. By way of example, but in a non-limiting manner, the counter-mold may comprise six first angular sectors 421 ensuring the compaction of the annular wall 414 of the preform 410, six second angular sectors 422 ensuring the compaction of the first folded portion 411 of the preform 410 and six third angular sectors 423 ensuring the compaction of the second folded portion 412 of the 410 preform.

[0052] In [Fig.4], only one angular sector of the plurality of first angular sectors, one angular sector of the plurality of second angular sectors and one sector of the plurality of third angular sectors are visible.

[0053] As illustrated in [Fig. 5], the mold 400 may comprise a profile 440 intended to protect the preform 410 from the formation of a fold or pinch. Thus, the mold according to the present invention may be similar to the RTM injection mold 300 illustrated in FIGS. 1A and 1B and further comprise the profile according to the invention.

[0054] The profile 440 can be placed between the fiber preform 410 wound on the mandrel 431 and the angular sectors 421, 422, 423 of the counter-mold. The profile 440 can have a ring shape, for example a circular ring shape, for example a closed ring shape ([Fig.6]).

[0055] The profile 440 may be configured to extend around the circumference of at least a portion of the preform 410.

[0056] For example, the profile 440 may be configured to extend over the circumference, for example the entire circumference, of a portion 412' of one of the two folded portions 412 of the preform 412 and / or over the circumference, for example the entire circumference of at least one portion of the annular wall 414 of the preform 410.

[0057] For example, the profile 440 may be configured to extend around the circumference, for example the entire circumference of the part 412' of the folded portion 412 (for example the second folded portion 412) of the preform 410 on which the angular sectors 423 would be deposited and which is opposite a second part 412” of the folded portion 412 of the preform 410, the second part 412” bearing against one of the lateral flanges 432 of the mandrel 433. It is understood that the profile is configured to extend over the entire surface of said part 412' of the folded portion 412 intended to form one of the flanges 13 of the casing.

[0058] As illustrated in [Fig. 5], the profile 440 may be configured to extend around the circumference, for example the entire circumference, of at least a portion of the annular wall 414 of the preform 410 intended to form the annular wall 11 of the fan casing 10.

[0059] The annular wall 414 of the preform 410 may for example comprise, as illustrated in [Fig. 4], an upstream portion 414', for example proximal to the first folded portion 411 of the preform 410, a downstream portion 414”, for example proximal to the second folded portion 412 of the preform 410 and a central portion 414'” arranged between the upstream portion 414' and the downstream portion 414”.

[0060] In the example illustrated in [Fig.5], the profile can be configured to extend around the circumference, for example the entire circumference of the downstream part 414” of the annular wall 414 of the preform 410. It is understood that the profile is configured to extend around the entire contour, for example the entire periphery, for example the entire surface of this part of the annular wall 414.

[0061] In a variant not illustrated, the profile 440 can be configured to extend around the circumference, for example the entire circumference of the entire annular wall 414 of the preform 410. The profile 440 can thus have an internal diameter slightly greater than the external diameter of the annular wall of the preform 410. This configuration is particularly advantageous in the case where it is desired to protect the annular wall 414 from the formation of folds and pinches.

[0062] The invention is particularly addressed to the problems of pinching and / or folds which appear at the level of the folded portions intended to form the upstream and downstream flanges of the fan casing when closing the mold by means of the counter-mold.

[0063] Also, the present invention relates more particularly to the protection of the folded portions of the preform intended to form flanges of the fan casing.

[0064] Thus, as illustrated in [Fig. 5], the profile 440 can be configured to extend over the circumference of a part 412' of one of the two folded portions 412 and over the circumference of at least one part, for example the downstream part 414”, of the annular wall 414 of the preform 410.

[0065] The profile 440 can thus comprise a portion 442 configured to extend over the circumference of a part 412' of the two folded portions 412 of the fiber preform 410 and a portion 444 configured to extend over the circumference of a part 414" of the annular wall 414 of the fiber preform 410.

[0066] The profile 440 may for example comprise a cross-section having two legs forming for example a non-zero angle, the first leg of which corresponds to the portion 442 configured to extend over the circumference of a part 412' of the two folded portions 412 of the fiber preform 414 and the second leg of which corresponds to the portion 444 configured to extend over the circumference of a part 414" of the annular wall 414 of the fiber preform 410.

[0067] The profile 440 may for example comprise a V- or L-shaped cross-section of which the first leg of the V or L corresponds to the portion 442 configured to extend over the circumference of a part 412' of the two folded-back portions 412 of the fiber preform 410 and of which the second leg of the V or L corresponds to the portion 444 configured to extend over the circumference of a part 414" of the annular wall 414 of the fiber preform 410.

[0068] In [Fig. 5], only one angular sector 423, of the plurality of third angular sectors, ensuring the compaction of the second folded portion 412 of the preform 410 with its profile 440 are shown. When the preform 410 comprises two folded portions 411, 412 in order to form two flanges of the fan casing to be manufactured, the mold 400 may comprise another profile 440 as previously described, which may be placed between the preform 410 and the plurality of second angular sectors 422 ensuring the compaction of the first folded portion 411 of the preform. The second profile 440 may be configured to extend over the circumference of a portion 411' of the other folded portion 411 of the fiber preform 410 and over the circumference of another portion 414' of the annular wall 414 of the fiber preform 410, for example the upstream portion 414' of the annular wall 414 as illustrated in [Fig.4].Thus the mold can comprise two profiles 440 as previously described intended to be placed between the wound fiber preform. on the mandrel, in particular respectively between each of the folded portions of the fiber preform, and the corresponding angular sectors of the counter-mold.

[0069] Each profile 440 can be formed in a single piece, that is to say in a single piece, that is to say that each profile 440 can be made in one piece.

[0070] The profile 440 can be made of woven or metallic material, which allows it to withstand the injection step.

[0071] For example, the profile can be manufactured from a preform made by:

[0072] - draping of unidirectional or bidirectional folds of carbon fibers, of fibers of glass or a mixture of carbon and glass fibers, each ply being pre-impregnated with a matrix precursor such as an epoxy resin for example,

[0073] - infusion of an epoxy resin into a dry fibrous texture obtained for example by draping unidirectional or bidirectional folds,

[0074] - draping of unidirectional or bidirectional folds of carbon fibers, of fibers of glass or a mixture of carbon and glass fibers, each ply being pre-impregnated with a resin or thermoplastic material such as polyetheretherketone (PEEK), polyetherketoneketone (PEKK) polyaryletherketones (PAEK), polyetherimide (PEI).

[0075] The profile preform can then be shaped and heat treated to transform the resin or thermosetting material (polymerization) or thermoplastic (heating then cooling) into a matrix.

[0076] According to a particularly preferred embodiment, each profile 440 can be made of metallic material, in particular by sheet metal stamping or additive manufacturing (for example by nickel electrodeposition).

[0077] The profile made of metallic material may have a thickness less than or equal to 0.2 mm or have a thickness greater than 0.2 mm.

[0078] When the profile has a thickness greater than 0.2 mm, it has the advantage of being able to be reused. Indeed, with a thickness less than 0.2 mm, the profile can undergo deformations during the manufacturing process of the fan casing and therefore cannot be reused. The profile can thus be designed in a more economical / ecological approach by providing a thicker profile that can be reused after each injection.

[0079] For example, the profile 440 may have a thickness of between 0.2 mm and 1 mm. This range of values ​​demonstrates the best compromise for having a profile that is reusable but remains flexible enough to be able to integrate it into the mold, that is to say the best compromise of durability and flexibility.

[0080] When the profile 440 comprises several portions, for example the two portions 442, 444 as previously described, each of the portions may have a thickness as previously described.

[0081] A system according to the invention may comprise a mold 400 as previously described and a preform 410 as previously described. The fiber preform 410 may be wound onto the mandrel 433 of the mold 430.

[0082] The manufacture of a fan casing 10 is now described.

[0083] The manufacture of a composite material fan casing begins with the implementation place by winding a fiber reinforcement on a mandrel whose profile matches that of the casing to be produced. The fiber reinforcement can be produced, for example, by three-dimensional or multi-layer weaving as described in US patent 8,322,971. This fiber reinforcement is shaped to constitute a single piece comprising a tubular portion and folded portions intended to form the upstream and downstream flanges of the fan casing.

[0084] For example, a fiber preform 410 as previously described may first be wound onto the mandrel 431 of a mold 400 according to the invention. Once the preform is wound onto the mandrel, the mold must be closed to compact the preform 410. Manufacturing continues by depositing a counter-mold on the fiber preform to close the mold. For this, the angular sectors may be assembled on the mandrel in a sealed manner. Before this step, the profile (or profiles) may be placed between the preform and the angular sectors, for example resting on a part of one of the folded portions of the preform and resting on a part of the annular wall of the preform.

[0085] To be able to place the profile 440 on the preform wound on the mandrel, it is possible to create an opening in the profile so as to be able to open the part and place it on the mandrel. Once the profile is placed, it will be possible to hold the cut-out area, for example using tape. Alternatively, it is possible to dismantle part of the mold in order to be able to place the profile, then reassemble the mold once the profile is placed.

[0086] Thanks to the shaped profile 440 it is no longer necessary to successively place each of the sheets of the prior art between two angular sectors. The ring-shaped profile can be placed in a single step before adding the angular sectors.

[0087] When the angular sectors are assembled on the mandrel, the profile 440 extends between the preform 410 and the corresponding angular sectors. The profile is positioned against the internal faces of the corresponding angular sectors.

[0088] A polymerizable resin is then injected into the mold by a pressure differential (by an RTM type process), and the latter is polymerized (by heating or cooling for example, depending on the nature of the resin used). The fan casing thus produced can then be demolded.

[0089] The invention relates more particularly to the manufacturing method where the impregnation The fiber preform is produced using the injection molding process known as RTM (for "Resin Transfer Molding"). According to this process, once the counter-mold, whose shape corresponds to the part of revolution that we want to obtain, is placed on the fiber preform, the resin is injected under controlled pressure and temperature inside the mold. Once the resin is injected, it is polymerized by heating the mold and after injection and polymerization, the final part is demolded and then trimmed to remove excess resin and the chamfers are machined to obtain the desired final part, for example a fan casing.As the preform is expanded when it is wound onto the mandrel, i.e. it has an excess thickness compared to the theoretical thickness of the final part, closing the mold also ensures the function of definitively compacting the preform to bring it to its final thickness.

Claims

Claims

1. Mold (400) intended to be used for the manufacture of a gas turbine fan casing (10) made of composite material, the mold comprising: - a mandrel (431) on which a fibrous preform (410) of fan casing is intended to be wound, the mandrel comprising an annular wall whose profile of the external surface corresponds to that of the internal surface (14) of the casing to be manufactured and two lateral flanges (430) whose profiles correspond to those of flanges (12, 13) of the casing to be manufactured; - a plurality of angular counter-mold sectors (421, 422, 423) intended to close the mold and to compact the fiber preform wound on the mandrel, the mold further comprising a ring-shaped profile (440) intended to be placed between the fiber preform wound on the mandrel and the angular counter-mold sectors (421, 422, 423).

2. The mold (400) of claim 1 wherein the profile (440) is formed as a single piece.

3. Mold (400) according to any one of claims 1 and 2 wherein the fiber preform (410) intended to be wound on the mandrel (430) comprises an annular wall (414) intended to form an annular wall (11) of the casing (10) to be manufactured and two folded portions (411, 412) intended to form flanges (12, 13) of the casing to be manufactured and wherein the profile (440) is configured to extend over the circumference of a part (411', 412') of one of the two folded portions (411, 412) of the preform intended to form the flanges of the casing to be manufactured and / or over the circumference of at least one part (414', 414”) of the annular wall (414) of the preform (410) intended to form the annular wall (11) of the casing to be manufactured.

4. Mold (400) according to claim 3 wherein the profile (440) comprises a portion (442) configured to extend around the circumference of a part (411', 412') of one of the two folded portions (411, 412) of the fiber preform (410) and a portion (444) configured to extend around the circumference of a part (414', 414”) of the annular wall (414) of the fiber preform (410).

5. A mold (400) according to claim 4 wherein the profile (440) comprises a cross-section having two legs forming a angle, the first leg of which corresponds to the portion (442) configured to extend over the circumference of a part (411', 412') of one of the two folded portions (411, 412) of the fiber preform (410) intended to form the flanges of the casing and the second leg of which corresponds to the portion (444) configured to extend over the circumference of a part (414', 414”) of the annular wall (414) of the fiber preform (410).

6. Mold (400) according to any one of the preceding claims in which the profile (440) is made of metallic material.

7. Mold (400) according to claim 6 wherein the profile (440) has a thickness greater than 0.2 mm.

8. Mold (400) according to claim 7 wherein the profile (440) has a thickness of between 0.2 mm and 1 mm.

9. Method for closing an injection mold (400) according to claim 1, the method comprising the steps of: - sealing the angular sectors (421, 422, 423) of the counter-mold on the mandrel (433) of the mold; and - placing the profile (440) between the fiber preform (410) wound on the mandrel and the angular sectors of the counter-mold.

10. A method of manufacturing a gas turbine fan casing made of composite material comprising: - winding a fiber preform (410) onto the mandrel (433) of a mold according to claim 1; - closing the mold according to the method of claim 9; - injecting a resin into the mold (400); and - demolding the fan casing (10).

Images