FR3066226A1 - LOCKING STATOR RING UNDER HIGH PRESSURE DISPENSER - Google Patents

Abstract

The invention relates to a turbomachine assembly comprising: - a turbine distributor (40), - an annular distributor support housing (5), connected to the distributor (40), comprising a first annular support flange (501) connected to a axial injector (55), and a second annular support flange (502), said flanges (501, 502) extending axially from the housing (5), - a stop (51) connected to the housing (5), and configured to blocking the housing (5) in position relative to the distributor (40), and - holding means (6) of the stop (51), characterized in that the holding means (6) of the stop (51) comprise an annular wedge (6) extending radially between the second support flange (502) and the stop (51).

Description

TECHNICAL FIELD The invention relates to a set of parts for a turbomachine. The invention relates more specifically to the supports of turbine distributors, for example of a high pressure turbine.

STATE OF THE ART

A turbomachine turbine conventionally comprises fixed elements, constituting the stator, and mobile elements, constituting the rotor, centered on a longitudinal axis of the turbomachine.

The mobile elements are blades carrying wheels, rotating around the longitudinal axis of the turbomachine, and interposed between grids of fixed blades, also called distributor. The distributor / wheel assembly constitutes a turbine stage.

To facilitate the assembly of the turbine, the distributors are sometimes obtained by assembling at least two distributor sectors. Each distributor sector can include a number of fixed blades distributed between a radially outer ring, relative to the longitudinal axis of the turbomachine, called the outer platform, and a radially inner ring, called the inner platform. Generally, the inner platform is extended radially inward by a hooking flange used to fix the distributor, or the distributor sector, on a support part. This support piece also serves as a hook for the injectors supplying the rotor, when the injectors are arranged axially relative to the longitudinal axis of the turbomachine. Thereafter, the term “distributor” will be used to designate an entire distributor or a sector of distributor.

There is shown in Figure 1 an existing design of turbine distributor support 10. In FIG. 1, there is a turbine stage comprising: - a wheel 11, comprising a movable blade 110 mounted by its foot in a cell 111 of the rotor disk 112, and - a distributor 10, comprising a fixed blade 101 connected by its foot has an annular lower platform 102 and an annular distributor attachment flange 103.

The wheel 11 and the distributor 10 extend radially, from a longitudinal axis X-X of a turbomachine, within a flow stream 12 of hot air.

The annular distributor attachment flange 103 extends radially from the lower platform 102, and makes it possible to connect the fixed vane 101 to a support part comprising an annular casing 2.

The casing 2 is connected to an axial injector 24 by means of a first annular support flange 201 extending axially from the casing 2.

The connection between the distributor 10 and the casing 2 is ensured by the cooperation of the annular distributor attachment flange 103 and an annular housing attachment flange 203 which extends radially from the housing 2.

This cooperation implements a set of connecting pins 22 extending axially through the annular distributor attachment flange 103 and the annular housing attachment flange 203, and distributed circumferentially around the axis X-X. The presence of the connecting pins 22 prevents the circumferential movements of the hooking flanges 103, 203 relative to one another.

This cooperation also implements at least one stop pin 21 extending radially through the support casing 2, and configured to axially lock the hooking flanges 103, 203 against each other.

This cooperation is also sealed against the infiltration of air from the flow stream 12 by means of an elastic seal 23.

The distributor support 10 also comprises an annular wedge 3 extending between the first annular extension 201 and the annular housing attachment flange 203.

The wedge 3 is connected to the casing 2 by means of a central flange 31 connected to a second annular support flange 202 extending axially from the casing 2 by means of a bolted connection 32.

In addition, the wedge 3 supports, at its radially external portion, the stop pin 21.

The wedge 3 finally comprises a portion of abradable 33 disposed opposite the rotating sealing wipers 34 connected to the wheel 11.

The presence of the wedge 3 makes it possible to stabilize the dispenser support 10 by limiting the movements of the various support elements both in radial and axial directions. This assembly also makes it possible to protect the axial injector 24, during operation of the turbine. However, the presence of the bolted connection 32 increases the distributor support 10 and prevents its implementation in small turbomachinery. In this regard, it has in particular been proposed in document FR 2 908 153, in the name of the Applicant, a fastening device for a private distributor of bolted connection. In this device, an annular casing and shim are kept fitted by a circumferential holding part configured to prevent relative movements of the casing and of the shim relative to one another. However, such a device involves substantially modifying the connection between the casing and the distributor to accommodate the presence of the holding part, which is not desirable to facilitate the maintenance of existing machines.

There is therefore a need to propose a compact and light distributor support assembly, which can be implemented in small turbomachinery at low cost, and whose maintenance is facilitated.

SUMMARY OF THE INVENTION

An object of the invention is to provide a turbine distributor support assembly having the characteristic of being compact.

Another object of the invention is to provide a turbine distributor support assembly which is light.

Another object of the invention is to provide a turbine distributor support assembly suitable for small turbomachinery.

Another object of the invention is to reduce the manufacturing costs of a distributor support assembly for a turbine.

Another object of the invention is to facilitate the maintenance of turbine distributor supports by simplifying the assembly and disassembly of such supports.

Another object of the invention is to provide a set of turbomachines forming a distributor support that is sealed against the infiltration of hot air from the flow stream of the turbine.

Another object of the invention is to provide a turbine distributor support assembly allowing the use of axial injectors. The invention proposes in particular an assembly for a turbomachine comprising: - a turbine distributor, - an annular distributor support casing comprising a first annular support flange connected to an axial injector, and a second annular support flange, said flanges extending axially from the casing, - a stopper connected to the casing, and configured to lock the casing in position relative to the distributor, and - means for retaining the stopper, characterized in that the means for retaining the stopper comprise an annular wedge s' extending radially between the second support flange and the stop.

In such an assembly for a turbomachine, the bolted connection has been removed from the distributor support casing, and the size of the annular shim is reduced compared to the assemblies of the prior art. The assembly is therefore lighter, more compact, and suitable for small engines. In addition, only the shape of the annular shim is modified compared to the assemblies of the prior art, the support casing and the stop remaining generally unchanged. This facilitates the implementation of the assembly in existing turbomachinery, while facilitating assembly, disassembly, and maintenance. This set finally makes it possible to conserve the use of axial injectors. The assembly according to the invention may further include the following characteristics: - it comprises a ring of circlip type, disposed between the wedge and an annular retaining edge of the casing, and configured to prevent axial movements of the wedge relative to the second support flange, - the support casing and the distributor are connected by means comprising at least one fixing pin, - the casing comprises an annular housing attachment flange and the distributor comprises an annular distributor attachment flange, said attachment flanges extending radially respectively from the housing and the distributor, the fixing pin extending axially through the housing and distributor attachment flange, - the shim has a general shape of U, the branches of which are in contact with the second support flange and the stop, - it includes an annular seal between the distributing hook flange uteur, and the housing hooking flange, - the gasket is elastic, for example is a bellows spring, - the stop comprises a pin extending radially through an axial annular housing flange, and - The housing comprises a transverse annular flange, and the first and the second support flange extend axially from said transverse flange. The invention also relates to a turbomachine comprising an assembly as described above.

QUICK DESCRIPTION OF THE FIGURES Other characteristics, objects and advantages of the present invention will appear on reading the detailed description which follows and with reference to the appended drawings given by way of non-limiting example and in which: - Figure 1, already described, schematically illustrates a sectional view of an example of a turbomachine assembly forming a distributor support known from the prior art, - Figure 2 schematically illustrates a sectional view of an exemplary embodiment of a set of turbomachine forming a distributor support according to the invention, - Figure 3 is a first perspective view of an embodiment of a turbomachine assembly forming a distributor support according to the invention, and - Figure 4 is a second perspective view of an embodiment of a turbomachine assembly forming a distributor support according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the figures, an embodiment of an assembly for a turbomachine forming a distributor support 40 for a turbomachine turbine, for example a high pressure turbine, will now be described.

As described above, a turbomachine turbine comprises fixed elements, constituting the stator, and mobile elements, constituting the rotor, centered on a longitudinal axis X-X of the turbomachine.

The stator comprises a distributor 40. In addition, the rotor comprises a wheel 41. Finally, the distributor 40 / wheel 41 assembly constitutes a turbine stage centered on the axis X-X.

The distributor 40 is fixed, by its radially internal portion relative to the axis XX, to a support piece 5. This support piece 5 also serves as a hook for the injectors 55 supplying the rotor, when the injectors 55 are arranged axially with respect to the XX axis.

More specifically, the support of the turbine distributor 40 is provided by an assembly for a turbomachine which comprises: - a distributor 40, comprising a fixed vane 401 connected by its foot to an annular lower platform 402 comprising an annular distributor attachment flange 403 extending radially from the lower platform 402, - an annular casing 5, comprising an annular attachment flange 503 which extends radially from the casing 5, a first annular support flange 501 connected to an axial injector 55, and a second annular support flange 502, which extend axially from the casing 5, - a stop 51 connected to the casing 5, and configured to lock the casing 5 in position relative to the distributor 40, and - means 6 for holding the abutment 51 , said means 6 comprising an annular wedge 6 extending radially between the second annular support flange 502 and the stop 51.

The presence of the wedge 6 makes it possible to stabilize the assembly forming the distributor support 40 by limiting the radial and axial movements, relative to the axis X-X, of the various support elements. In addition, not using a bolted connection to connect the shim 6 to the housing 5 makes it possible to lighten the support, while making it more compact by 50%. Furthermore, not using the bolted connection reduces maintenance times by simplifying the assembly and disassembly of the distributor support 40. In addition, the radial height of the support assembly is identical to that of the assemblies of the prior art, which keeps the axial injector 55 at its level within current turbines.

The turbine wheel 41 comprises a movable blade 410 mounted by its foot in a cavity 411 of the rotor disc 412. The wheel 41 and the distributor 40 extend radially, from a longitudinal axis XX of the turbomachine, within a vein of hot air flow 42.

As illustrated in FIG. 2, the wheel 41 may further comprise a sealing wiper 56 extending radially relative to the axis XX, and configured to prevent the infiltration of air from the flow stream 42 of hot air. The wipers 56 rotate around the axis XX at the same time as the rotor, and can then cooperate with a portion of abradable 54 disposed opposite rotating sealing wipers 56, and extending radially from the second annular support flange 502.

As illustrated in FIGS. 2 to 4, the casing 5 can comprise a transverse annular casing flange 506 and an axial annular casing flange 505. Two planes locally tangent respectively to the axial flange 505 and to the hooking flange 503 are then substantially orthogonal. In addition, the first support flange 501 and the second support flange 502 then extend axially from the transverse flange 506.

The annular distributor attachment flange 403 makes it possible to connect the stationary vanes 401 to the annular housing 5, by cooperating with the annular housing attachment flange 503.

As illustrated in FIGS. 2 to 4, this cooperation can implement a set of fixing pins 52 extending axially through the annular distributor attachment flange 403 and the annular housing attachment flange 503, and distributed circumferentially around the axis XX. Finally, all of the fixing pins 52 prevent relative rotation of the distributor 40 and of the casing 5 relative to each other, while allowing the axial differential expansions of the hooking flanges 403 and 503 due to the difference temperature between upstream and downstream of the distributor.

In addition, as illustrated in FIGS. 2 to 4, this cooperation is stabilized by the presence of the stop 51, which axially blocks the movement of the hooking flanges 403 and 503.

The stop 51 is held by the wedge 6 and also makes it possible to withstand the radial forces, for example of vibration, coming from the distributor 40.

The stop 51 may be in the form of a radial pin 51 extending through the axial flange 505. The head of the pin 51 is then placed opposite the wedge 6, while the body extends in a radial direction towards the distributor 40. The maintenance of the assembly is then facilitated, by simplifying the assembly and disassembly operations. As illustrated in FIG. 3, in an embodiment where the stop 51 is formed by one (or more) radial pins 51, and the cooperation between distributor 40 and casing 5 is implemented by connecting pins 52, the body of stop pins 51 and link pins 52 can enter into spatial conflict. It is therefore preferable to arrange the stop pins 51 and the radial pins 52 alternately in circumference around the axis X-X.

In addition, as illustrated in FIGS. 2 to 4, this cooperation can be made airtight against the infiltration of air from the flow stream 42, for example by means of an elastic seal 53, disposed between the flange distributor attachment 403, and housing attachment flange 503. The elastic seal 53 can then advantageously be a bellows spring, the properties of which make it possible to seal the cooperation despite the pressure difference between the 'upstream and downstream of the distributor. In any event, the elastic seal 53 is able to withstand relative movements of the distributor attachment flanges 403 and of the casing 503 in an axial direction, while preventing the infiltration of air from the vein d flow 42. The elastic seal 53 is machined from a material capable of withstanding the high temperatures at this level of the turbomachine, that is to say typically of the order of 600 to 700 ° C. The use of pins fixing 52, a stop pin 51, and an elastic seal 53 being common with the supports already known, this makes it possible to reduce the costs of implementing such an assembly in current turbomachines, while facilitating maintenance.

As illustrated in FIGS. 2 to 4, the casing can also comprise an annular casing retaining flange 504, extending radially in the extension of the casing hooking flange 503. The assembly forming the distributor support can then comprise a ring 7 of the circlip type disposed between the wedge 6 and the retaining flange 504. The ring 7 makes it possible to limit the axial movements of the wedge 6 relative to the second support flange 502. The presence of the combined circlip ring 7 to that of the annular shim 6, in place of the bolted connection in the assemblies forming the distributor support of the prior art, allows a weight gain of approximately 40%, while ensuring the same functions.

As illustrated in FIGS. 2 to 4, the shim 6 can have a general U-shape. In this case, each of the branches of the U can come to bear respectively against the second support flange 502 and against the stop 51. Furthermore, in one embodiment of the distributor support assembly 40 comprising a circlip ring 7, the hollow of the U of the wedge 6 can come to bear against said ring in order to prevent axial movements of the wedge 6 relative to the second support flange 502.

The general "U" shape makes it possible to accommodate the radial movements of the different elements of the distributor support assembly 40, so as to stabilize it, while being compact and light.

Claims (10)

1. An assembly for a turbomachine comprising: - a turbine distributor (40), - an annular distributor support casing (5), comprising a first annular support flange (501) connected to an axial injector (55), and a second annular flange support (502), said flanges (501, 502) extending axially from the casing (5), - a stop (51) connected to the casing (5), and configured to lock the casing (5) in position relative to the distributor (40), and - means for holding (6) the stop (51), characterized in that the means (6) for holding the stop (51) comprise an annular wedge (6) extending radially between the second support flange (502) and the stop (51). 2. The assembly as claimed in claim 1, comprising a ring (7) of the circlip type, disposed between the shim (6) and an annular housing retaining rim (504), and configured to prevent axial movements of the shim (6) relative to the second support flange (502). 3. Assembly according to one of claims 1 or 2, wherein the support casing (5) and the distributor (40) are connected by means comprising at least one fixing pin (52). 4. The assembly of claim 3, wherein the housing (5) comprises an annular housing attachment flange (503) and the distributor (40) comprises an annular distributor attachment flange (403), said flanges latching (403, 503) extending radially from the housing (5) and the distributor (40) respectively, the fixing pin (52) extending axially through the housing coupling flange (503) and distributor (403). 5. Assembly according to one of claims 1 to 4, wherein the shim (6) has a general shape of U, the branches of which are in contact with the second support flange (502) and the stop (51). 6. Assembly according to one of claims 1 to 5, comprising an annular seal (53) disposed between the distributor attachment flange (403), and the housing attachment flange (503). 7. The assembly of claim 6, wherein the seal (53) is elastic, for example is a bellows spring. 8. Assembly according to one of claims 1 to 7, wherein the stop (51) comprises a pin (51) extending radially through an axial annular housing flange (505). 9. Assembly according to one of claims 1 to 8, in which the casing comprises a transverse annular flange (506), and the first (501) and the second (502) support flange extend axially from said transverse flange (506 ). 10. Turbomachine comprising an assembly according to any one of the preceding claims.