CN117167103A - Turbine outer ring connection structure, middle bearing casing, gas turbine engine and connection method - Google Patents

Abstract

The application provides a turbine outer ring connecting structure, a middle bearing casing, a gas turbine engine and a connecting method. The turbine outer ring connection structure includes: the turbine outer ring piece comprises a turbine outer ring body and an extension part, wherein the extension part extends from the turbine outer ring body to the radial outside and is axially adjacent to the first rib plate and the second rib plate; the middle bearing casing comprises a first casing part, a second casing part and a connecting part, wherein the first casing part and the second casing part are arranged in a split mode; the connecting part comprises a telescopic section, and the two sides of the telescopic section in the axial direction are respectively and detachably connected with the first casing part and the second casing part; the thermal expansion coefficient of the turbine outer ring is smaller than that of the middle bearing casing. An effect of preventing thermal stress generated by thermal mismatch is achieved.

Description

Turbine outer ring connection structure, middle bearing casing, gas turbine engine and connection method

Technical Field

The application relates to the field of aero-engines, in particular to a turbine outer ring connecting structure, a middle bearing casing, a gas turbine engine and a connecting method.

Background

CMC ceramic matrix composites are a class of composites that use ceramics as a matrix to be composited with various fibers. The ceramic matrix can be high-temperature structural ceramics such as silicon nitride, silicon carbide and the like. CMC ceramic matrix composites have excellent properties of high temperature resistance, high strength and stiffness, low density, relatively light weight, corrosion resistance, etc., and have been applied to high Wen Reduan components of aero-engines, such as outer rings, tail-jet systems, flame barrels, etc. Is regarded as the first choice for replacing high-temperature alloy and realizing the weight-reducing and efficiency-increasing 'upgrading and upgrading materials' of the novel advanced engine.

Disclosure of Invention

The application aims to provide a turbine outer ring connecting structure.

It is a further object of the present application to provide a gas turbine engine.

It is still another object of the present application to provide a center receiver.

It is a further object of the application to provide a method of connection.

According to an aspect of the present application, a turbine outer ring connection structure includes: the turbine outer ring piece comprises a turbine outer ring body and an extension part, wherein the extension part comprises a first rib plate and a second rib plate which are axially adjacent and extend outwards from the turbine outer ring body in a radial direction; the middle bearing casing comprises a first casing part, a second casing part and a connecting part, wherein the first casing part and the second casing part are arranged in a split mode; the first casing part is correspondingly detachably connected with the first rib plate, the second casing part is correspondingly detachably connected with the second rib plate, the connecting part comprises a telescopic section, and two sides of the telescopic section in the axial direction are respectively detachably connected with the first casing part and the second casing part; and the thermal expansion coefficient of the turbine outer ring piece is smaller than that of the middle bearing casing.

According to the technical scheme, the axial dimensions of the middle bearing casing and the turbine outer ring piece are adjusted by arranging the telescopic section, so that the middle bearing casing is allowed to axially displace under the condition of a high-temperature field in the running process of the engine, and high stress is prevented from being generated due to axial constraint of the middle bearing casing and the turbine outer ring piece.

According to one or more embodiments of the turbine outer ring connection structure, the first rib plate and the second rib plate are respectively provided with a first connection hole and a second connection hole; the first casing part and the second casing part of the middle bearing casing are respectively provided with a third connecting hole corresponding to the first connecting hole and a fourth connecting hole corresponding to the second connecting hole; the turbine outer ring connecting structure further comprises a first connecting piece and a second connecting piece; the first connecting piece is connected with the first connecting hole and the third connecting hole, the first rib plate is in surface-to-surface tight connection with the first casing part, the first rib plate is positioned on the axially downstream side of the first casing part, and an elastic piece is arranged at the contact position of the first connecting piece and the first rib plate; the second casing part comprises a first section and a second section, the fourth connecting hole comprises a first hole section and a second hole section, an axial space is reserved between the first section and the second section, the second rib plate is axially located in the axial space, the axial size of the second rib plate is smaller than that of the axial space, and the second connecting piece is sequentially connected with the first hole section of the fourth connecting hole, the second connecting hole and the second hole section of the fourth connecting hole in the axial direction from upstream to downstream.

In one or more embodiments of the turbine outer ring connection structure, the turbine outer ring connection structure includes a cold state and a hot state:

in the cold state, the first casing part is in close contact with the first rib plate, the first section of the second casing part is in close contact with the second rib plate, and the second section of the second casing part and the second rib plate have a first axial gap;

in the thermal state, the first casing part is in tight contact with the first rib plate, the first section of the second casing part is in tight contact with the second rib plate, the second section of the second casing part and the second rib plate have a second axial gap, and the second axial gap is smaller than the first axial gap.

According to one or more embodiments of the turbine outer ring connection structure, the first section of the second casing portion includes a first body and a first protruding portion, the second section includes a second body and a second protruding portion, the first protruding portion protrudes from the first body toward an axial downstream direction, the second protruding portion protrudes from the second body toward an axial upstream direction, and the first protruding portion and the second protruding portion are used for limiting the second rib plate axially.

According to one or more embodiments of the turbine outer ring connection structure, the thermal expansion coefficients of the first connecting piece and the second connecting piece are the same as those of the middle bearing casing, and the first connecting piece and the second connecting piece are in clearance fit with the first connecting hole and the second connecting hole respectively.

In one or more embodiments of the turbine outer ring connection structure, the first, second, third and fourth connection holes are coaxially disposed in an axial direction.

In one or more embodiments of the turbine outer ring connection structure, the first section includes a first section body and a first section connector, the second section includes a second section body and a second section connector, the first section connector has a first hole section of the fourth connection hole, the second section connector has a second hole section of the fourth connection hole, the first section connector and the second section connector have the axial space therebetween, the second rib is axially located in the axial space, and an axial dimension of the second rib is smaller than a dimension of the axial space; the first section body and the second section body are in face-to-face tight detachable fixed connection, and the first section body is in detachable connection with the connecting part.

According to one or more embodiments of the turbine outer ring connection structure, the first casing portion includes a first casing portion body and a first mounting portion, the first mounting portion is detachably connected with the first rib plate, a cold air channel is provided in the first casing portion body, and the cold air channel is communicated with a space defined by the middle bearing casing and the turbine outer ring.

According to one or more embodiments of the turbine outer ring connection structure, the connection portion further includes a first connection portion and a second connection portion, which are respectively connected to two axial ends of the telescopic section, the first connection portion and the second connection portion respectively have a fifth connection hole and a sixth connection hole, the first casing portion and the second casing portion respectively have a seventh connection hole and an eighth connection hole, and the turbine outer ring connection structure further includes a third connection member and a fourth connection member, the third connection member is connected to the fifth connection hole and the seventh connection hole to connect the first casing portion and the first connection portion, and the fourth connection member is connected to the sixth connection hole and the eighth connection hole to connect the second casing portion and the second connection portion.

In one or more embodiments of the turbine outer ring connection structure, the telescoping section is bellows-like.

According to one or more embodiments of the turbine outer ring connection structure, the turbine outer ring is made of a ceramic matrix composite material, and the intermediate bearing casing is made of a high-temperature alloy.

A gas turbine engine according to another aspect of the application comprises a turbine outer ring connection as described above.

According to still another aspect of the application, a middle bearing casing comprises a first casing part, a second casing part and a connecting part, wherein the first casing part and the second casing part are arranged in a split mode; the connecting part comprises a telescopic section, and the telescopic section is detachably connected with the first casing part and the second casing part at two axial sides respectively.

According to a further aspect of the present application, a method for attaching a first ring member to a second ring member coaxial therewith, the first ring member being of a first material and the second ring member being of a second material, the first material having a coefficient of thermal expansion that is less than a coefficient of thermal expansion of the second material, comprises:

the first annular piece is provided with a first rib plate and a second rib plate which are axially adjacent and extend outwards from the first annular piece in a radial direction, and the first rib plate and the second rib plate are respectively provided with a first connecting hole and a second connecting hole;

a first part and a second part which are arranged as separate parts on the second annular piece and a connecting part which is positioned between the first part and the second part and is used for connecting the first part and the second part;

the first part is arranged to be detachably connected with the first rib plate correspondingly, the second part is arranged to be detachably connected with the second rib plate correspondingly, the connecting part comprises a telescopic section, the length of the telescopic section in the axial direction is telescopic, and the two sides of the telescopic section in the axial direction are detachably connected with the first part and the second part respectively; the first annular member has a coefficient of thermal expansion that is less than a coefficient of thermal expansion of the second annular member.

Drawings

The above and other features, properties and advantages of the present application will become more apparent from the following description of the accompanying drawings and embodiments in which like reference numerals refer to like features throughout, it being noted that these drawings are given by way of example only, which are not drawn to scale and should not be construed to limit the true scope of the application, wherein:

FIG. 1 is a schematic view of an embodiment of a turbine outer ring connection structure;

FIG. 2 is a schematic view of an alternative view of an outer ring connection structure of an embodiment of a turbine;

fig. 3 is a schematic structural diagram of a connecting portion according to an embodiment.

Detailed Description

Reference will now be made in detail to the various embodiments of the application, examples of which are illustrated in the accompanying drawings and described below. While the application will be described in conjunction with the exemplary embodiments, it will be appreciated that the present description is not intended to limit the application to those exemplary embodiments. On the contrary, the application is intended to cover not only these exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the application as defined by the appended claims.

In the following description, references to orientations or positional relationships of "radial," "axial," "inner," "outer," or other azimuthal terms are based on the orientation or positional relationships shown in the drawings, and are merely for convenience in describing the application and simplifying the description, rather than to indicate or imply that the device or component referred to must have a particular orientation, be configured and operated in a particular orientation, and therefore should not be construed as limiting the application.

Meanwhile, the present application uses specific words to describe embodiments of the present application. Reference to "one embodiment" and/or "an embodiment" means that a particular feature, structure, or characteristic is associated with at least one embodiment of the application. Thus, it should be emphasized and should be appreciated that two or more references to "an embodiment" or "one embodiment" in various positions in this specification are not necessarily referring to the same embodiment. Furthermore, certain features, structures, or characteristics of one or more embodiments of the application may be combined as suitable.

At present, with increasing requirements on weight reduction and efficiency improvement of aeroengines, further improvement of engines is required.

Through intensive researches, the inventor of the application discovers that the thermal conductivity and the thermal expansion coefficient of the CMC ceramic matrix composite material and the metal material have larger difference, the deformation of the metal material is large under the high-temperature environment, and the deformation of the CMC ceramic matrix composite material is small, so that the connection between the CMC ceramic matrix composite material and the metal material is particularly important, the functions of the structure, the load transmission and the displacement limitation are ensured, and the damage of the CMC ceramic matrix composite material caused by inconsistent deformation of the metal material and the CMC ceramic matrix composite material is also required to be avoided. Therefore, CMC is applied to aeroengine parts by adopting an outer ring made of ceramic matrix composite materials, and the problem of thermal mismatch connection between the outer ring and a metal piece needs to be considered. Thermal mismatch refers to a phenomenon that adjacent materials or components with different thermal expansion coefficients in the same system show inconsistent thermal expansion deformation in the temperature change process, which is called a thermal mismatch phenomenon, and unreleasable thermal mismatch can cause significant thermal mismatch stress in the system.

Based on the above considerations, the inventor has designed a turbine outer ring connection structure through intensive research, through setting up scalable section, realizes adjusting the axial dimensions of well bearing box and turbine outer ring spare, and when the engine operation in-process, under high temperature field condition, the axial displacement takes place for well bearing box, prevents well bearing box and the axial constraint of turbine outer ring spare to produce high stress. In addition, the structure of the turbine outer ring piece is similar to pi shape, and the manufacturing is convenient.

Although the turbine outer ring connection structure disclosed in the embodiment of the application is suitable for a gas turbine engine to achieve the effect of preventing thermal stress generated by thermal mismatch, the application is not limited thereto, and the connection structure disclosed in the embodiment of the application can be applied as long as the connection is used for preventing high stress caused by non-uniform deformation.

Referring to fig. 1, in one embodiment, the turbine outer ring connection structure 100 may specifically include a turbine outer ring member 1 and a middle bearing casing 2. The turbine outer ring 1 comprises a turbine outer ring body 11 and an extension 12, the extension 12 comprising axially adjacent first and second ribs 121, 122 extending radially outwardly from the turbine outer ring body 11. The middle bearing casing 2 comprises a first casing part 21, a second casing part 22 and a connecting part 23 which are arranged in a split mode. The first casing portion 21 is detachably connected to the first rib 121, the second casing portion 22 is detachably connected to the second rib 122, the connecting portion 23 includes a telescopic section 230, and two sides of the telescopic section 230 in the axial direction are detachably connected to the first casing portion 21 and the second casing portion 22 respectively. The thermal expansion coefficient of the turbine outer ring 1 is smaller than that of the intermediate bearing casing 2.

The term "turbine outer ring 1" as used herein refers to the component of an aircraft engine that isolates high temperature gas washout and maintains the structural integrity of the casing.

The meaning of the "middle bearing case 2" here refers to the main bearing part on the aeroengine, belonging to the stationary part. When the engine blade falls off, the blade is contained.

The axial dimension adjusting device has the beneficial effects that the axial dimension adjusting device is used for adjusting the axial dimension of the middle bearing casing and the axial dimension adjusting device of the turbine outer ring piece through the telescopic section, and when an engine runs, the middle bearing casing is allowed to axially displace under the condition of a high-temperature field, so that high stress is prevented from being generated due to axial constraint of the middle bearing casing and the turbine outer ring piece.

Referring to fig. 1 in combination with fig. 2, in some embodiments, the turbine outer ring connection structure 100 may have a specific structure in which the first rib 121 and the second rib 122 have a first connection hole 311 and a second connection hole 32, respectively. The first casing portion 21 and the second casing portion 22 of the intermediate bearing casing 2 have third connecting holes 5 corresponding to the first connecting holes 31 and fourth connecting holes 6 corresponding to the second connecting holes 32, respectively. The turbine outer ring connection 100 also includes a first connection 35 and a second connection 46. The first connecting member 35 is connected to the first connecting hole 31 and the third connecting hole 5, the first rib 121 is tightly connected to the first casing 21 on an axial surface-surface, the first rib 121 is located on an axial downstream side of the first casing 21, and the elastic member 7 is provided at a contact position between the first connecting member 35 and the first rib 121. In some embodiments, as shown in fig. 2, the elastic member 7 is a spring washer.

The second casing portion 22 includes a first section 221, a second section 222, the fourth connecting hole 6 includes a first hole section 601 and a second hole section 602, an axial space a is provided between the first section 221 and the second section 222, the second rib 122 is axially located in the axial space a, and an axial dimension of the second rib 122 is smaller than that of the axial space a, and the second connecting piece 46 is sequentially connected with the first hole section 601, the second connecting hole 32 and the second hole section 602 of the fourth connecting hole 6 in an axial upstream-downstream direction.

The beneficial effects of this embodiment lie in, with well bearing the receiver by traditional whole well bearing the receiver divide into first receiver portion, second receiver portion and lie in the piecemeal design of the junction between the two, make things convenient for the assembly and the dismantlement of structure. By arranging the telescopic section, the axial dimension of the middle bearing casing is adjusted, the axial displacement of the middle bearing casing can be allowed in the running process of the engine, and the axial stress of the middle bearing casing can be released. Through setting up the connecting piece, make whole connection structure more firm and easy dismouting. By arranging the elastic piece and the axial space, the middle bearing casing and the turbine outer ring piece both allow axial deformation displacement, and the principle is that, for example, as shown in fig. 2, the first casing part 21 is clung to the first rib plate 121, the elastic piece 7 is arranged between the first rib plate 121 and the first connecting piece 35, when heat mismatch occurs, the first casing part 21 is subjected to thermal deformation and displacement towards the axial downstream to push the first rib plate 121, and the first rib plate 121 presses the elastic piece 7 to perform axial displacement until the elastic piece 7 cannot be compressed; the second rib 122 leaves an axial space with the second section 222, allowing the first section 221 to displace axially downstream to drive the second rib 122 to displace axially downstream until it engages the second section 222. Therefore, the limit of the turbine outer ring piece can be realized, the difference of thermal expansion coefficients of the middle bearing casing and the turbine outer ring piece can be prevented, the middle bearing casing is prevented from deforming downstream at high temperature, high stress is generated on the root parts of the first rib plate and the second rib plate, and damage is avoided. The structure can be ensured to be firm enough in the installation state; in the thermal mismatch state, the overstress can be effectively prevented.

In some embodiments, as shown in fig. 2, the first and second connectors 35, 46 are bolts.

With continued reference to FIG. 1 in conjunction with FIG. 2, in some embodiments, the turbine outer ring connection 100 may be configured such that the turbine outer ring connection 100 includes a cold state and a hot state:

in the cold state, the first casing portion 21 is tightly connected to the first rib 121, the first segment 221 of the second casing portion 22 is tightly connected to the second rib 122, and the second segment 222 of the second casing portion 22 has a first axial gap with the second rib 122. At the moment, in the installation state, the turbine outer ring connecting structure can be ensured to be firm enough, and enough space is reserved for the thermal deformation of the middle bearing casing, so that the turbine outer ring can adaptively move according to the running condition of the engine, deformation and load are released, and high stress is prevented.

In the hot state, the first casing part 21 is connected in a tight contact with the first rib 121, the first section 221 of the second casing part 22 is connected in a tight contact with the second rib 122, the second section 222 of the second casing part 22 has a second axial gap with the second rib 122, which is smaller than the first axial gap, and the second axial gap may even be 0. When the engine runs, in a high-temperature state, the thermal deformation amount of the middle bearing casing is larger than that of the turbine outer ring piece, and the whole is displaced towards the axial downstream, so that the axial gap between the second section and the second rib plate is reduced until the second section is attached to the second rib plate, the limit of the turbine outer ring piece is realized, and damage caused by thermal mismatch stress is prevented.

In some embodiments, as shown in fig. 1 and 2, in the cold state installation state, the middle receiver 2 is in radial contact with the upper end surfaces of the first rib 121 and the second rib 122; when the engine runs, under the action of high temperature and internal and external cavity pressure, the radial outer deformation of the middle bearing casing 2 is larger than that of the turbine outer ring 1, and the upper end surfaces of the middle bearing casing 2, the first rib plate 121 and the second rib plate 122 automatically release a certain clearance, so that the middle bearing casing 2 is prevented from generating excessive radial load on the turbine outer ring 1, damage is caused, and meanwhile, the radial limiting function is also realized.

With continued reference to fig. 1 and fig. 2, in some embodiments, the second casing 22 may have a specific structure that the first section 221 of the second casing 22 includes a first body 2211 and a first protruding portion 2212, the second section 222 includes a second body 2221 and a second protruding portion 2222, the first protruding portion 2212 protrudes from the first body 2211 axially downstream, the second protruding portion 2222 protrudes from the second body 2221 axially upstream, and the first protruding portion 2212 and the second protruding portion 2222 are used to axially limit the second rib 122. The first protruding portion and the second protruding portion have the beneficial effects that the second rib plate is axially limited, the contact area with the second rib plate is reduced, the machining precision of the contact surface is convenient to guarantee, and the second rib plate is easy to machine. In addition, the weight of the second casing part can be reduced by the design, and the effect of light weight design is achieved.

With continued reference to fig. 1 and fig. 2, in some embodiments, the specific structure of the turbine outer ring connection structure 100 may be that the thermal expansion coefficients of the first connection member 35 and the second connection member 46 are the same as those of the middle bearing casing 2, and the first connection member 35 and the second connection member 46 are in clearance fit with the first connection hole 31 and the second connection hole 32 respectively.

The "same thermal expansion coefficient" is substantially the same, that is, the difference between the thermal expansion coefficients of the first and second connection members and the thermal expansion coefficient of the intermediate carrier is negligible compared to the difference between the thermal expansion coefficient of the turbine outer ring member and the thermal expansion coefficient of the intermediate carrier. For example, the materials of the first connecting piece, the second connecting piece and the middle bearing casing are completely the same, and for example, the materials of the first connecting piece, the second connecting piece and the middle bearing casing are nickel-based superalloy, but belong to nickel-based superalloy with different brands, and the situation also belongs to the situation that the thermal expansion coefficients of the first connecting piece and the second connecting piece are the same as the thermal expansion coefficient of the middle bearing casing.

The clearance fit's setting can prevent effectively that the thermal mismatch stress of connecting hole and connecting piece, also is favorable to well holding the axial displacement of receiver and turbine outer ring spare simultaneously, prevents that the root of first floor, second floor from producing high stress, leads to damaging.

Referring to fig. 2, in some embodiments, the turbine outer ring connection structure 100 may be embodied such that the first connection hole 31, the second connection hole 32, the third connection hole 5, and the fourth connection hole 6 are coaxially disposed in an axial direction. The beneficial effect of this arrangement lies in, can promote turbine outer ring spare and well bearing casing to remove in same direction, more easily release thermal stress.

Referring to fig. 1 in combination with fig. 2, in some embodiments, the specific structure of the second casing portion 22 may be that the first segment 221 includes a first segment body 2201 and a first segment connector 2202, the second segment 222 includes a second segment body 2203 and a second segment connector 2204, the first segment connector 2201 has a first hole segment 601 of the fourth connecting hole 6, the second segment connector 2204 has a second hole segment 602 of the fourth connecting hole 6, an axial space a is between the first segment connector 2202 and the second segment connector 2204, the second rib 122 is axially located in the axial space a, and an axial dimension of the second rib 122 is smaller than a dimension of the axial space a; the first segment body 2201 is detachably and fixedly connected to the second segment body 2203 in a surface-to-surface manner, and the first segment body 2201 is detachably connected to the connecting portion 23. The arrangement not only leaves space for axial displacement of the second casing part, but also limits the second rib plate, and meanwhile, the assembly is easier.

In some embodiments, as shown in fig. 1 and 2, the first segment body 2201 has a ninth connecting hole 51, the second segment body 2203 has a tenth connecting hole 52, the first segment body 2201 and the second segment body 2203 are connected by a fifth connecting piece 9, and the fifth connecting piece 9 is a countersunk screw, so that the disassembly is convenient.

With continued reference to fig. 1 and fig. 2, in some embodiments, the specific structure of the first casing portion 21 may include a first casing portion body 211 and a first mounting portion 212, where the first mounting portion 212 is detachably connected to the first rib 121, and the first casing portion 21 body is provided with a cold air channel 8, and the cold air channel 8 communicates with a space b defined by the intermediate casing 2 and the turbine outer ring 1, so as to reduce the temperature of the turbine outer ring and the intermediate casing.

In some embodiments, as shown in fig. 2, the centers of the first connecting member 35 and the second connecting member 46 are provided with a hole for communicating with the space b, so as to discharge the cool air entering from the cooling channel 8, promote the circulation of the air flow, and make the cooling effect better.

Referring to fig. 1 to 3, in some embodiments, the specific structure of the connection portion 23 may further include a first connection portion 231 and a second connection portion 232, which are respectively connected to two axial ends of the telescopic section 230, the first connection portion 231 and the second connection portion 232 respectively have a fifth connection hole 40 and a sixth connection hole 41, the first casing portion 21 and the second casing portion 22 respectively have a seventh connection hole 42 and an eighth connection hole 43, the turbine outer ring connection structure 100 further includes a third connection member 44 and a fourth connection member 45, the third connection member 44 is connected to the fifth connection hole 40 and the seventh connection hole 42 to connect the first casing portion 21 and the first connection portion 23, and the fourth connection member 45 is connected to the sixth connection hole 41 and the eighth connection hole 43 to connect the second casing portion 22 and the second connection portion 23, so as to make the connection more stable. In some embodiments, as shown in fig. 2, the third and fourth connectors 44, 45 are bolts.

Referring to fig. 3, in some embodiments, the specific structure of the telescopic section 230 may be that the telescopic section 230 is bellows-shaped, which is easy to manufacture, has better flexibility, is beneficial to the axial displacement of the middle bearing casing, and prevents thermal stress caused by thermal mismatch.

Referring to fig. 1, in some embodiments, the turbine outer ring connection structure 100 may be specifically configured such that the turbine outer ring 1 is a ceramic matrix composite material, and the middle bearing casing 2 is a superalloy. The structure of the outer ring piece of the turbine adopting the ceramic-based composite material is similar to pi-shaped, so that the outer ring piece of the turbine is convenient to manufacture, and meanwhile, the ceramic-based composite material is used, so that the outer ring piece of the turbine has excellent characteristics of high temperature resistance, high hardness and the like, and meanwhile, the weight of the outer ring piece of the turbine is reduced, and the light-weight design is realized.

In one embodiment, a specific structure of the gas turbine engine may be a turbine outer ring connection structure including those described above. The gas turbine engine adopting the turbine outer ring connecting structure can effectively insulate heat, can obviously improve the temperature before the turbine of the engine and improve the performance of the engine. Meanwhile, the turbine outer ring connecting structure limits the turbine outer ring, and simultaneously allows the middle bearing casing and the turbine outer ring to axially displace, so that stress release is realized, thermal mismatch stress caused by overhigh temperature is not needed, and the components are damaged.

Referring to fig. 1, in one embodiment, the middle carrier 2 may have a specific structure including a first casing portion 21, a second casing portion 22, and a connecting portion 23 therebetween. The connecting portion 23 includes a telescopic section 230, and the telescopic section 230 is detachably connected to the first casing portion 21 and the second casing portion 22 at two axial sides. The middle bearing casing is divided into a plurality of designs, and the traditional integral middle bearing casing is divided into a first casing part, a second casing part and a connecting part positioned between the first casing part and the second casing part, so that the assembly is easy. The telescopic section can adjust the axial dimension of the middle bearing casing, can allow the axial displacement of the middle bearing casing in the running process of the engine, and can release the axial stress of the middle bearing casing.

Referring to fig. 1 to 3, in one embodiment, a method for attaching a first ring member to a second ring member coaxial therewith, the first ring member being made of a first material, the second ring member being made of a second material, the first material having a coefficient of thermal expansion smaller than that of the second material, may include the steps of:

the first ring-shaped member is provided with a first rib plate and a second rib plate which are axially adjacent and extend outwards from the first ring-shaped member, and the first rib plate and the second rib plate are respectively provided with a first connecting hole and a second connecting hole. As mentioned above, the first environmental element is the turbine outer ring element 1, and includes the turbine outer ring body 11 and the extension 12, and the extension 12 includes the axially adjacent first rib 121 and the second rib 122 extending radially outward from the turbine outer ring body 11. The first rib 121 and the second rib 122 have a first connection hole 311 and a second connection hole 32, respectively.

The second annular piece is provided with a first part, a second part and a connecting part, wherein the first part and the second part are separated, and the connecting part is positioned between the first part and the second part and is used for connecting the first part and the second part. The second ring member is the middle bearing casing 2, and includes a first casing portion 21, a second casing portion 22, and a connecting portion 23 therebetween.

The first part is arranged to be correspondingly detachably connected with the first rib plate, the second part is arranged to be correspondingly detachably connected with the second rib plate, the connecting part comprises a telescopic section, the length of the telescopic section in the axial direction is telescopic, and the two sides of the telescopic section in the axial direction are respectively detachably connected with the first part and the second part; the first annular member has a coefficient of thermal expansion that is less than the coefficient of thermal expansion of the second annular member. As mentioned above, the first casing portion 21 is detachably connected to the first rib 121 correspondingly, the second casing portion 22 is detachably connected to the second rib 122 correspondingly, the connecting portion 23 includes a telescopic section 230, and two sides of the telescopic section 230 in the axial direction are detachably connected to the first casing portion 21 and the second casing portion 22 respectively. The thermal expansion coefficient of the turbine outer ring 1 is smaller than that of the intermediate bearing casing 2.

By adopting the connecting method of the embodiment, the first annular piece and the second annular piece are allowed to axially displace, thermal mismatch stress caused by thermal mismatch generated by different coefficients of thermal expansion is effectively prevented, component damage occurs, and the first annular piece can be limited.

While the application has been described in terms of preferred embodiments, it is not intended to be limiting, but rather to the application, as will occur to those skilled in the art, without departing from the spirit and scope of the application. Therefore, any modification, equivalent variation and modification of the above embodiments according to the technical substance of the present application fall within the protection scope defined by the claims of the present application.

Claims (14)

1. A turbine outer ring connection structure, comprising:

the turbine outer ring piece comprises a turbine outer ring body and an extension part, wherein the extension part extends from the turbine outer ring body to the radial outside and is provided with a first rib plate and a second rib plate which are adjacent to each other in the axial direction;

the middle bearing casing comprises a first casing part, a second casing part and a connecting part, wherein the first casing part and the second casing part are arranged in a split mode;

the first casing part is correspondingly detachably connected with the first rib plate, the second casing part is correspondingly detachably connected with the second rib plate, the connecting part comprises a telescopic section, and two sides of the telescopic section in the axial direction are respectively detachably connected with the first casing part and the second casing part; and the thermal expansion coefficient of the turbine outer ring piece is smaller than that of the middle bearing casing.

2. The turbine outer ring connection structure as set forth in claim 1, wherein:

the first rib plate and the second rib plate are respectively provided with a first connecting hole and a second connecting hole;

the first casing part and the second casing part of the middle bearing casing are respectively provided with a third connecting hole corresponding to the first connecting hole and a fourth connecting hole corresponding to the second connecting hole;

the turbine outer ring connecting structure further comprises a first connecting piece and a second connecting piece;

the first connecting piece is connected with the first connecting hole and the third connecting hole, the first rib plate is in surface-to-surface tight connection with the first casing part, the first rib plate is positioned on the axially downstream side of the first casing part, and an elastic piece is arranged at the contact position of the first connecting piece and the first rib plate;

the second casing part comprises a first section and a second section, the fourth connecting hole comprises a first hole section and a second hole section, an axial space is reserved between the first section and the second section, the second rib plate is axially located in the axial space, the axial size of the second rib plate is smaller than that of the axial space, and the second connecting piece is sequentially connected with the first hole section of the fourth connecting hole, the second connecting hole and the second hole section of the fourth connecting hole in the axial direction from upstream to downstream.

3. The turbine outer ring connection structure of claim 2, wherein the turbine outer ring connection structure includes a cold state and a hot state:

in the cold state, the first casing part is in close contact with the first rib plate, the first section of the second casing part is in close contact with the second rib plate, and the second section of the second casing part and the second rib plate have a first axial gap;

in the thermal state, the first casing part is in tight contact with the first rib plate, the first section of the second casing part is in tight contact with the second rib plate, the second section of the second casing part and the second rib plate have a second axial gap, and the second axial gap is smaller than the first axial gap.

4. The turbine outer ring connecting structure according to claim 2, wherein the first section of the second casing portion includes a first body and a first protruding portion, the second section includes a second body and a second protruding portion, the first protruding portion protrudes axially downstream from the first body, the second protruding portion protrudes axially upstream from the second body, and the first protruding portion and the second protruding portion are used for axially limiting the second rib.

5. The turbine outer ring connection structure according to claim 2, wherein the thermal expansion coefficients of the first connecting piece and the second connecting piece are the same as those of the middle bearing casing, and the first connecting piece and the second connecting piece are in clearance fit with the first connecting hole and the second connecting hole respectively.

6. The turbine outer ring connection structure according to claim 2, wherein the first connection hole, the second connection hole, the third connection hole, and the fourth connection hole are coaxially disposed in an axial direction.

7. The turbine outer ring connection structure according to claim 2, wherein the first section includes a first section body and a first section connector, the second section includes a second section body and a second section connector, the first section connector has a first hole section of the fourth connection hole, the second section connector has a second hole section of the fourth connection hole, the first section connector and the second section connector have the axial space therebetween, the second rib is axially located in the axial space, and an axial dimension of the second rib is smaller than a dimension of the axial space; the first section body and the second section body are in face-to-face tight detachable fixed connection, and the first section body is in detachable connection with the connecting part.

8. The turbine outer ring connection structure according to claim 1, wherein the first casing portion includes a first casing portion body and a first mounting portion detachably connected to the first rib, and the first casing portion body is provided with a cold air passage communicating a space defined by the intermediate bearing casing and the turbine outer ring.

9. The turbine outer ring connecting structure according to claim 1, wherein the connecting portion further comprises a first connecting portion and a second connecting portion, which are respectively connected with the two axial ends of the telescopic section, the first connecting portion and the second connecting portion respectively have a fifth connecting hole and a sixth connecting hole, the first casing portion and the second casing portion respectively have a seventh connecting hole and an eighth connecting hole, and the turbine outer ring connecting structure further comprises a third connecting member and a fourth connecting member, the third connecting member is connected with the fifth connecting hole and the seventh connecting hole to connect the first casing portion with the first connecting portion, and the fourth connecting member is connected with the sixth connecting hole and the eighth connecting hole to connect the second casing portion with the second connecting portion.

10. The turbine outer ring connection structure of claim 1, wherein the telescoping sections are bellows-like.

11. The turbine outer ring connection structure of claim 1, wherein the turbine outer ring member is a ceramic matrix composite and the intermediate bearing casing is a superalloy.

12. A gas turbine engine comprising the turbine outer ring connection of any one of claims 1-11.

13. The middle bearing casing is characterized by comprising a first casing part, a second casing part and a connecting part, wherein the first casing part and the second casing part are arranged in a split mode; the connecting part comprises a telescopic section, and the telescopic section is detachably connected with the first casing part and the second casing part at two axial sides respectively.

14. A method of joining a first ring member to a second ring member coaxial therewith, the first ring member being of a first material and the second ring member being of a second material, the first material having a coefficient of thermal expansion less than a coefficient of thermal expansion of the second material, comprising:

the first annular piece is provided with a first rib plate and a second rib plate which are axially adjacent and extend outwards from the first annular piece in a radial direction, and the first rib plate and the second rib plate are respectively provided with a first connection hole and a second connection hole;

a first part and a second part which are arranged as separate parts on the second annular piece and a connecting part which is positioned between the first part and the second part and is used for connecting the first part and the second part;

the first part is arranged to be detachably connected with the first rib plate correspondingly, the second part is arranged to be detachably connected with the second rib plate correspondingly, the connecting part comprises a telescopic section, the length of the telescopic section in the axial direction is telescopic, and the two sides of the telescopic section in the axial direction are detachably connected with the first part and the second part respectively; the first annular member has a coefficient of thermal expansion that is less than a coefficient of thermal expansion of the second annular member.