DEVICE FOR FASTENING SEALING PLATES BETWEEN COMPONENTS OF A GAS TURBINE ENGINE

Abstract

A device for fastening sealing plates between components of a gas turbine engine includes guide vane ring which includes guide vane segments, wherein each guide vane segment includes an outer platform and an inner platform, sealed off from one another at ends by a sealing strip. The device furthermore includes a plurality of sealing plates which seal off the guide vane segments from a component which is adjacent in the upstream or downstream direction. The sealing strips in each case form a sealing section and an extension section, wherein the sealing section serves to seal off two mutually adjoining platforms, the extension section extends axially forward or axially rearward, starting from the sealing section, and projects from the platforms, and the extension section forms a holding element for at least one sealing plate or is connected to a separate holding element.

Claims

1. A device for fastening sealing plates between components of a gas turbine engine, wherein the device has: a guide vane ring which comprises a plurality of guide vane segments, wherein each guide vane segment comprises an outer plate, an inner platform and at least one guide vane, the outer platforms and the inner platforms of in each case two adjacent guide vane segments adjoin one another at the ends, and, in this arrangement, in each case two platforms are sealed off from one another at the ends by means of a sealing strip, wherein the platforms each form an axially extending groove at their ends, and the sealing strip is inserted into the grooves of the platforms, and wherein the sealing strip extends in the grooves from the axially forward end of the platforms to the axially rearward end of the platforms, a plurality of sealing plates which seal off the guide vane segments from a component which adjoins the guide vane segments in the upstream or downstream direction, wherein in that the sealing strips in each case form a sealing section and an extension section in the region of the outer and/or the inner platforms, wherein the sealing section serves to seal off two mutually adjoining platforms, the extension section extends axially forward, starting from the sealing section, and projects from the platforms, and the extension section forms a holding element for at least one sealing plate or is connected to a separate holding element.

2. The device as claimed in claim 1, wherein in that the sealing section of a sealing strip is in each case inserted into the grooves of two adjacent platforms, wherein the extension section projects from the grooves in the downstream direction.

3. The device as claimed in claim 1, wherein the extension section is of wider design in the circumferential direction than the sealing section.

4. The device as claimed in claim 1, wherein the extension section forms a section which extends substantially in the radial direction and in the circumferential direction and is of flat design,

5. The device as claimed in claim 1, wherein the extension section forms a groove which extends in the circumferential direction and is used to retain and accommodate at least one adjoining sealing plate.

6. The device as claimed in claim 5, wherein the section which extends substantially in the radial direction and in the circumferential direction is bent back at its radially outer end and thereby forms a groove.

7. The device as claimed in claim 5, wherein the extension section has a length in the circumferential direction such that two adjacent sealing plates can be inserted into the groove of the extension section.

8. The device as claimed in claim 1, wherein the extension section is connected to a holding element for at least one sealing plate, said holding element being designed as a separate part.

9. The device as claimed in claim 8, wherein the holding element forms a section which extends substantially in the radial direction and in the circumferential direction, is of flat design and is bent back at its radially outer end and thereby forms a groove extending in the circumferential direction.

10. The device as claimed in claim 1, wherein the extension section is of resilient design and exerts a spring force on at least one of the sealing plates.

11. The device as claimed in claim 10, wherein the extension section forms a region bent in a U shape or a region bent in a meandering shape.

12. The device as claimed in claim 10, wherein the extension section is of resilient design and exerts an axially acting spring force on the holding element.

13. The device as claimed in claim 1, wherein radial noses which fix the sealing plates in the circumferential direction in relation to the holding elements are formed on said sealing plates.

14. The device as claimed in claim 13, wherein the radial noses are formed at a distance from the lateral ends of the sealing plates and adjoin the respectively adjacent holding element on the outside in the circumferential direction.

15. The device as claimed in claim 1, wherein the guide vane ring is a turbine guide vane ring, wherein the sealing plates are designed to seal off the turbine guide vane ring from a combustion chamber arranged upstream.

16. The device as claimed in claim 1, wherein the sealing strips are composed of a metal or a metal alloy.

17. A gas turbine engine which comprises a combustion chamber and a turbine guide vane ring arranged downstream of the combustion chamber, wherein the device as claimed in claim 1, by means of which sealing plates provided between the combustion chamber and the turbine guide vane ring are fastened.

18. A device for fastening sealing plates between components of a gas turbine engine, wherein the device has: a guide vane ring which comprises a plurality of guide vane segments, wherein each guide vane segment comprises an outer platform, an inner platform and at least one guide vane, the outer platforms and the inner platforms of in each case two adjacent guide vane segments adjoin one another at the ends, and, in this arrangement, in each case two platforms are sealed off from one another at the ends by means of a sealing strip, wherein the platforms each form an axially extending groove at their ends, and the sealing strip is inserted into the grooves of the platforms, and wherein the sealing strip extends in the grooves from the axially forward end of the platforms to the axially rearward end of the platforms, a plurality of sealing plates which seal off the guide vane segments from a component which adjoins the guide vane segments in the upstream or downstream direction, wherein in that a respective fastening element for at least one sealing plate is provided in the region of the outer and/or the inner platforms, wherein the fastening element holds the at least one sealing plate or is connected to a separate holding element, which holds the at least one sealing plate, wherein the fastening element has: a fastening section, which is arranged together with the sealing strip in the grooves of two adjacent platforms and is held in said grooves, and a holding section, which extends axially forward, starting from the fastening section, and projects from the platforms in order to hold the at least one sealing plate or to be connected to the separate holding element.

19. The device as claimed in claim 18, wherein the fastening section is arranged only in an axially forward partial region of the grooves.

20. The device as claimed in claim 18, wherein the axially forward partial region of the grooves is widened relative to a downstream region of the grooves.

21. The device as claimed in claim 18, wherein the holding section is of resilient design and exerts a spring force on at least one of the sealing plates.

22. The device as claimed in claim 18, wherein the holding section is of resilient design and exerts a spring force on the separate holding element which holds the at least one sealing plate.

23. The device as claimed in claim 18, wherein the holding section forms a region bent in a U shape or a region bent in a meandering shape.

24. The device as claimed in claim 18, wherein the holding section is of wider design in the circumferential direction than the fastening section.

Description

[0065] The invention will be explained in more detail below on the basis of a plurality of exemplary embodiments with reference to the figures of the drawing. In the drawing:

[0066] FIG. 1 shows a lateral sectional view of a gas turbine engine;

[0067] FIG. 2 shows an embodiment of a turbine guide vane segment according to the prior art, wherein an outer platform and an inner platform of the turbine guide vane segment are sealed off from an adjoining combustion chamber by means of sealing plates;

[0068] FIG. 3 shows a partially sectioned view of the turbine guide vane segment of FIG. 2;

[0069] FIG. 4 shows a sectional illustration of a turbine guide vane segment of a guide vane ring of a high-pressure compressor, which is implemented in the main flow path, adjoining the combustion chamber, wherein the turbine guide vane segment comprises a device for fastening sealing plates between the turbine guide vane segment and the combustion chamber, said device comprising a sealing strip which forms an extension section for fastening sealing plates;

[0070] FIG. 5 shows a section through the turbine guide vane segment of FIG. 4 along the line A-A in FIG. 4;

[0071] FIG. 6 shows a section through the turbine guide vane segment of FIG. 4 along the line B-B in FIG. 4;

[0072] FIG. 7 shows a perspective illustration of the sealing strip of the device for fastening sealing plates between the turbine guide vane segment and the combustion chamber according to FIG. 4;

[0073] FIG. 8 shows an alternative embodiment of the extension section of the sealing strip of FIG. 4, wherein the extension section forms a spring region that is bent backward and forward in a meandering shape,

[0074] FIG. 9 shows a sectional illustration of another turbine guide vane segment of a guide vane ring of a high-pressure compressor, which is implemented in the main flow path, adjoining the combustion chamber, wherein, for the purpose of fastening sealing plates between the turbine guide vane segment and the combustion chamber, the turbine guide vane segment comprises a sealing strip having an extension section which is connected to a separate holding element for fastening sealing plates;

[0075] FIG. 10 shows the extension section and the holding element on the radially outer platform of the turbine guide vane segment of FIG. 9 on an enlarged scale;

[0076] FIG. 11 shows the extension section and the holding element on the radially inner platform of the turbine guide vane segment of FIG. 9 on an enlarged scale; and

[0077] FIG. 12 shows another exemplary embodiment of a turbine guide vane segment of a guide vane ring of a high-pressure compressor, wherein the turbine guide vane segment comprises a device for fastening sealing plates between the turbine guide vane segment and the combustion chamber, said device comprising a fastening element which forms a fastening section and a holding section.

[0078] FIG. 1 illustrates a gas turbine engine 10 having a main axis of rotation 9. The engine 10 comprises an air intake 12 and a thrust fan 23 that generates two air flows: a core air flow A and a bypass air flow B. The gas turbine engine 10 comprises a core 11 which receives the core air flow A. In the sequence of axial flow, the engine core 11 comprises a low-pressure compressor 14, a high-pressure compressor 15, a combustion device 16, a high-pressure turbine 17, a low-pressure turbine 19, and a core thrust nozzle 20. An engine nacelle 21 surrounds the gas turbine engine 10 and defines a bypass duct 22 and a bypass thrust nozzle 18. The bypass air flow B flows through the bypass duct 22. The fan 23 is attached to and driven by the low-pressure turbine 19 by way of a shaft 26 and an epicyclic gear box 30,

[0079] During use, the core air flow A is accelerated and compressed by the low-pressure compressor 14 and directed into the high-pressure compressor 15, where further compression takes place. The compressed air expelled from the high-pressure compressor 15 is directed into the combustion device 16, where it is mixed with fuel and the mixture is combusted. The resulting hot combustion products then propagate through the high-pressure and the low-pressure turbines 17, 19 and thereby drive said turbines, before being expelled through the nozzle 20 to provide a certain propulsive thrust. The high-pressure turbine 17 drives the high-pressure compressor 15 by means of a suitable connecting shaft 27. The fan 23 generally provides the major part of the thrust force. The epicyclic gear box 30 is a reduction gear box.

[0080] It is noted that the terms “low-pressure turbine” and “low-pressure compressor” as used herein can be taken to mean the lowest pressure turbine stage and the lowest pressure compressor stage (that is to say not including the fan 23) respectively and/or the turbine and compressor stages that are connected to one another by the connecting shaft 26 with the lowest rotational speed in the engine (that is to say not including the gear box output shaft that drives the fan 23). In some documents, the “low-pressure turbine” and the “low-pressure compressor” referred to herein may alternatively be known as the “intermediate-pressure turbine” and “intermediate-pressure compressor”. Where such alternative nomenclature is used, the fan 23 can be referred to as a first compression stage or lowest-pressure compression stage.

[0081] Other gas turbine engines in which the present disclosure can be used may have alternative configurations. For example, such engines may have an alternative number of compressors and/or turbines and/or an alternative number of connecting shafts. By way of a further example, the gas turbine engine shown in FIG. 1 has a split flow nozzle 20, 22, meaning that the flow through the bypass duct 22 has its own nozzle that is separate from and radially outside the core engine nozzle 20. However, this is not restrictive, and any aspect of the present disclosure can also apply to engines in which the flow through the bypass duct 22 and the flow through the core 11 are mixed or combined before (or upstream of) a single nozzle, which may be referred to as a mixed flow nozzle. One or both nozzles (whether mixed or split flow) can have a fixed or variable area. Although the example described relates to a turbofan engine, the disclosure can be applied, for example, to any type of gas turbine engine, such as, for example, an open rotor engine (in which the fan stage is not surrounded by an engine nacelle) or a turboprop engine. In some arrangements, the gas turbine engine 10 may not comprise a gear box 30.

[0082] The geometry of the gas turbine engine 10, and components thereof, is/are defined by a conventional axis system, comprising an axial direction (which is aligned with the axis of rotation 9), a radial direction (in the bottom-to-top direction in FIG. 1), and a circumferential direction (perpendicular to the view in FIG. 1). The axial, radial and circumferential directions run so as to be mutually perpendicular.

[0083] In the context of the present invention, the design of the transition between the combustion chamber 16 and the high-pressure turbine 17, in particular the configuration of the sealing of a gap between the combustion chamber 16 and the high-pressure turbine 17, are significant.

[0084] For a better understanding of the invention, the background of the invention will first of all be explained by means of an example of a turbine guide vane segment according to the prior art, which is illustrated in FIGS. 2 and 3. The turbine guide vane segment 4 comprises an outer platform 41, an inner platform 42 and one or more guide vanes 43, which extend in the radial direction between the inner platform 42 and the outer platform 41. A plurality of such turbine guide vane segments 4 forms a turbine guide vane ring, wherein the individual turbine guide vane segments 4 adjoin one another in the circumferential direction at the ends of their platforms 41, 42.

[0085] To seal off a radial gap which is formed as a matter of necessity between the combustion chamber 16 and the turbine guide vane segments 4, a plurality of sealing plates 5, which are each of elongate design and form a circular arc, is provided. As can be seen, in particular, from the illustration in FIG. 3, the sealing plates 5 are held by means of rivets 90 fastened on fastening projections 410, 420 of the respective platform 41, 42 and are provided with a contact pressure by means of spring elements 95. In this case, the rivets 90 pass through the sealing plates 5 in a respective fastening hole. The sealing plates 5 are pressed against the combustion chamber by means of the spring elements 95 and are supported on structures 415 of the turbine guide vane segments 4, ensuring in this way that the gap between the combustion chamber and the turbine guide vane segments 4 is sealed off by the sealing plates 5. However, leakage arises from gaps 55 which are formed between each of the rivets 90 and the fastening holes in the sealing plates 5. Moreover, the figure illustrates what is referred to as a secondary sealing plate 50, which covers a gap between two sealing plates 5 adjoining one another in the circumferential direction and thereby reduces leakage due to such a gap.

[0086] The prior art device for fastening the sealing plates 5 is relatively complex and heavy since separate rivets 90, spring elements 95 and fastening projections 410, 420 have to be provided. At the same time, it is not possible, owing to the gaps 55 and the associated leakage, for the radial gap between the combustion chamber 16 and the turbine guide vane ring to be sealed off completely. In order to avoid additional leakage through radial gaps situated between two mutually adjoining sealing plates 5, additional secondary sealing plates 50 are required.

[0087] FIG. 4 shows, in a sectional illustration, a subsection of the core engine of a gas turbine engine, wherein—in relation to the flow direction—the illustrated subsection shows the rear section of a combustion chamber 16 and a turbine guide vane segment 4 of a turbine guide vane ring 400 directly adjoining the combustion chamber 16. The turbine guide vane ring 400 is segmented and comprises a plurality of turbine guide vane segments 4, which adjoin one another in the circumferential direction.

[0088] The combustion chamber 16 comprises an outer combustion chamber wall 161 and an inner combustion chamber wall 162, wherein the terms “outer” and “inner” refer to the main flow path which runs through the core engine. For protection against the hot gas flow in the combustion chamber 16, the outer combustion chamber wall 161 is provided with a plurality of heat shingles 163, which are supported on the outer combustion chamber wall 161. In corresponding fashion, the inner combustion chamber wall 162 is provided with a plurality of heat shingles 164, which are supported on the inner combustion chamber wall 162.

[0089] The outer combustion chamber wall 161 forms part of an outer combustion chamber casing, of which a further wall structure 165 is illustrated. The inner combustion chamber wall 162 forms part of an inner combustion chamber casing, which likewise comprises further wall structures, of which a further wall structure 166 is illustrated.

[0090] Each turbine guide vane segment 4 of the turbine guide vane ring 400 comprises an outer platform 41, which delimits the main flow path through the core engine radially on the outside, an inner platform 42, which delimits the main flow path through the core engine radially on the inside, and at least one guide vane 43, which extends between the inner platform 42 and the outer platform 41. The outer platforms 41 of the turbine guide vane segments 4 and the inner platforms 42 of the turbine guide vane segments 4 together form an outer platform and an inner platform of the guide vane ring 400.

[0091] A groove 411, 421 extending substantially in the axial direction is formed in the end both of the radially outer platform 41 and of the radially inner platform 42. The grooves 411, 421 each serve to accommodate a sealing section 61, which likewise extends substantially in the axial direction in the grooves 411, 421 and thereby seals off two radially inner platforms 42 and two radially outer platforms 41 resting against one another at the ends. In this arrangement, the grooves 411, 421 and the sealing sections 61 arranged therein extend from the axially forward end of the platform 41, 42 to the axially rearward end of the platform 41, 42, ensuring that two platforms resting against one another at the ends are sealed off from one another in an effective manner. Such grooves 411,421 and sealing sections 61 arranged therein are known per se.

[0092] According to the exemplary embodiment in FIG. 4, unlike in the prior art, the sealing sections 61 are not sealing strips that extend completely in the grooves 411, 421. On the contrary, the sealing strips 6 provided form two sections, sealing section 61 and, in addition, an extension section 62, which, starting from the sealing section 61, extends axially forward and projects from the platforms 41, 42. In this case, it is envisaged that the extension section 62 forms a holding element for at least one sealing plate 5, which serves to seal off a radial gap 8 between the combustion chamber 16 and the guide vane segments 4.

[0093] Thus, the gap 8 between the combustion chamber 16 and the guide vane segments 4 is closed by a multiplicity of sealing plates 5. Each sealing element 5 is of elongate design and forms a circular arc. At end faces which are farmed in the circumferential direction at each end of a sealing element 5, two sealing elements 5 adjoin one another.

[0094] Here, it can be seen in FIG. 4 that each sealing element 5 adjoins a flange or a nose 415, 425 of the respective platform 41, 42 and the end face of a wall structure 165, 166 of the respective combustion chamber casing, as a result of which the gap 8 is closed both on the radially outer side and on the radially inner side.. In this arrangement, the sealing elements 5 are subject to a contact pressure which presses them against the structures 415, 425, 165, 166.

[0095] The retention of the sealing elements 5 and the generation of a contact pressure is accomplished by means of the extension section 62 of the sealing strip 6. In order to explain the design of the extension section 62, reference is additionally made to FIGS. 5, 6 and 7, wherein FIGS. 5 and 6 show sectional illustrations along the lines A-A and B-B of FIG. 4, and FIG. 7 is a perspective illustration of an outer platform 41, including a sealing strip 6 and a sealing element 5. The following statements apply in corresponding fashion to the radially inner platform 42 and to the sealing strip 6 formed there.

[0096] As can be seen from the sectional illustration in FIG. 6, the sealing section 61 of the sealing strip 6 extends at the ends, between two platforms 41 adjoining one another in the circumferential direction, in the grooves 411 of the two mutually adjoining platforms 41. Toward the axially forward end of the grooves 411, these merge into upwardly open recesses 412, thus enabling the sealing strip to emerge radially outward from the grooves 411. The sealing strip 6 then forms the extension section 62, which serves for the retention of the respective ends of two mutually adjoining sealing plates 5 and for the provision of a contact pressure.

[0097] In this case, it is envisaged that the extension section 62 is of wider design in the circumferential direction than the sealing section 61, as is readily apparent in the illustration in FIG. 5. It can furthermore be seen, particularly in FIGS. 5 and 7, that the extension section 62 forms a section 620 which extends substantially in the radial direction and in the circumferential direction, is of flat design and is bent back radially, namely=in the direction of the combustion chamber 16, at its radially outer end, in a section 621, to form a groove 64.

[0098] The two end sections 515, 525 of two adjacent sealing plates 51, 52 are inserted into the groove 64 and are held there at their upper edge. Adjoining the structure 415, the lower edge of the sealing plates 51, 52 rests on the radially outer platform 41. By virtue of the widening of the extension section 62, this section here forms a stable structure for the reception of the ends 515, 525 of two sealing plates 5 adjoining one another in the circumferential direction.

[0099] Attention is drawn to the fact that, because the extension section 62 covers a gap 85 formed between the ends of two adjacent sealing plates 51, 52, cf. FIG. 5, it is not necessary to use secondary sealing plates corresponding to the sealing plates 50 of the prior art in FIG. 2 to avoid additional leakage through such a gap 85.

[0100] In order to ensure exact positioning of the sealing plates 51, 52 relative to the extension section 62 designed as a holding element, the sealing plates 51, 52 have radially projecting noses 510, 520, cf. FIGS. 5 and 7. In this case, a radially projecting nose 510, 520 adjoins the extension section 62 in the circumferential direction. The noses 510, 520 define the region 515, 525 of the sealing plates 51, 52 which is inserted into the groove 64 of the extension section 62 and is held by the extension section 62.

[0101] Attention is drawn to the fact that the extension section 62 is of resilient design and accordingly simultaneously forms a spring element which transmits a contact pressure to the sealing plates 51, 52, even when there is no pressure difference.

[0102] In this respect, FIG. 8 shows an exemplary embodiment in which an additional spring force for the provision of a contact pressure is provided by means of an additional, meandering region 622 of the extension section 62. Here, the meandering region 622 (bellows) adjoins the sealing section 61 of the sealing strip 6 and, at its other end, merges into the section 620 extending substantially in the radial direction and in the circumferential direction. As in the exemplary embodiment in FIGS. 4-7, a groove 64 for the reception of the adjacent ends of two sealing plates 5 is formed here by means of a bent-over end section 621. In this respect, reference is made to the description of FIGS. 4-7.

[0103] FIGS. 9-11 show an alternative exemplary embodiment, which differs from the exemplary embodiments in FIGS. 4 to 8 in that the extension section 62 of the sealing strip 6 does not itself form a holding element for the sealing plates 5 but is instead connected to a holding element designed as a separate part. As regards the general construction of the combustion chamber 16, of the guide vane segments 4 and of the sealing plates 5, attention is drawn to the description of FIGS. 4 to 8.

[0104] As in the exemplary embodiments of FIGS. 4 to s, the sealing strip 6 is formed by two sections, a sealing section 61, which serves to seal off two mutually adjoining platforms 41, and an extension section 62, which is of shorter design however. As illustrated in FIGS. 9 and 10, the extension section 62 is formed in a U shape in the case of the outer platform 41, wherein the bent-back end of the U-shaped section 623 is connected to a separate holding element 7. The bent-back end of the U-shaped section 623 is brazed or welded to the holding element 7, for example.

[0105] In terms of its shape and holding function, the holding element 7 corresponds to sections 620, 621 of the holding element 62 in FIGS. 4 to 8. Thus, the holding element 7 comprises a section 70 which extends substantially in the radial direction and in the circumferential direction, is of flat design and is bent back at its radially outer end, in a section 71, in order thereby to form a groove 72 extending in the circumferential direction. The two mutually adjoining ends of two sealing plates 5 are inserted into the groove 72, with the result that they are held in the groove 72. Here, a contact pressure is provided by means of the extension section 62.

[0106] As illustrated in FIGS. 9 and 11, the extension section 62 in the case of the inner platform 42 is designed to extend substantially radially, wherein the end section 624 of the extension section is once again connected to a separate holding part 7. The connection is made by brazing or welding, for example. The design of the holding part 7 is as explained with reference to FIG. 10.

[0107] Attention is drawn to the fact that, just as in the other figures, the sealing section 61 in FIGS. 10 and 11 extends over the entire length of the grooves 411, 421 and not just over the short section illustrated.

[0108] FIG. 12 shows an alternative exemplary embodiment of a device for fastening sealing plates, which differs from the exemplary embodiments in FIGS. 4 to 11 in that the holding element for the sealing plate 5 is not provided by an extension section of a sealing strip but by a separate fastening element 60 which comprises a fastening section 630 and a holding section 640.

[0109] The general construction of the device corresponds to that in FIG. 4, wherein sealing plates 5 seal off a gap 8 which is formed between a combustion chamber 16 having an outer combustion chamber wall 161, heat shingles 163 and a wall structure 165, on the one hand, and an outer platform 41 having an end groove 411 and a sealing strip 6 arranged therein, on the other hand.

[0110] The fastening section 630 of the fastening element 60 is arranged in the groove 411 of the outer platform 41 (and a corresponding groove in the end of the adjacent platform), together with the sealing strip 6. In this case, the groove 411 has an axially forward partial region 411a which is widened relative to a partial region 411b, downstream thereof, of the groove 411. The sealing strip 6 and the fastening section 630 are arranged in contact with one another in the widened groove 411a. The fastening section 630 is prevented from falling out through its arrangement in the widened groove 411a. In this case, there can be nonpositive engagement through static friction of the fastening section 630 with respect to the wall of the groove 411a and with respect to the sealing strip 6. In addition, there can also be positive engagement by means of a curved shape of the groove 411a in the region in which the fastening section 630 is arranged.

[0111] Starting from the fastening section 630, the holding section 640 of the fastening element 60 extends axially forward and, at the same time, projects from the platform 41. In this case, the holding section 640 forms a first section 641, which is connected to a separate holding element 7 (being brazed or welded, for example), and a second section 642, which exerts a spring force on the separate holding element 7. For this purpose, the section 642 is designed to be curved in a meandering shape. The section 642 merges into the fastening section 630.

[0112] As in the exemplary embodiment in FIGS. 9-11, the holding element 7 comprises a section 70 which extends substantially in the radial direction and in the circumferential direction, is of flat design and is bent back at its radially outer end, in a section 71, in order thereby to form a groove 72 extending in the circumferential direction. Two mutually adjoining ends of the two sealing plates 5 are inserted into the groove 72.

[0113] In a manner corresponding to the embodiment in FIGS. 5 and 7, the holding section 640 of the fastening element 60 can be designed to be wider in the circumferential direction than the fastening section 630.

[0114] In the exemplary embodiment in FIG. 12, it is envisaged that the fastening element 60 is connected to a separate holding element 7, which holds the sealing plate 5, corresponding to the construction in FIGS. 9-11. As an alternative, however, it is also possible to provide a construction as per FIGS. 4-8, in which case the holding section 640 of the fastening element 60 is connected directly to the sealing plate 5, wherein the holding section 640 can be designed in a manner corresponding to the extension section in FIGS. 4-8.

[0115] Attention is furthermore drawn to the fact that it is also possible in a corresponding manner for a fastening element 60 comprising a fastening section and a holding section in the manner described to be arranged on the radially inner platform.

[0116] It will be understood that the invention is not limited to the embodiments described above, and various modifications and improvements can be made without departing from the concepts described herein. For example, the invention has been described above by means of exemplary embodiments in which the adjoining component is arranged upstream of the guide vane segments 4, and the extension section 62 of the sealing strip 6 accordingly extends axially forward. In a corresponding manner, provision can be made for the extension section to extend axially rearward in order to hold sealing plates which seal off the guide vane segments 4 from a component adjoining the guide vane segments in a downstream direction. It is furthermore possible, for example, for the sealing strip 6 to form a sealing section 61 and an extension section 62 only on the outer platform 41 or only on the inner platform 42, rather than on both platforms 41, 42.

[0117] Furthermore, except where mutually exclusive, any of the features may be used separately or in combination with any other features, and the disclosure extends to and includes all combinations and sub-combinations of one or more features that are described herein. If ranges are defined, said ranges thus comprise all of the values within said ranges as well as all of the partial ranges that lie in a range.