WO2016156211A1

WO2016156211A1 - Guide vane assembly

Info

Publication number: WO2016156211A1
Application number: PCT/EP2016/056571
Authority: WO
Inventors: Marco Dreymann; Erik Porsch; Achim Schirrmacher; Dimitri Zelmer
Original assignee: Siemens Aktiengesellschaft
Priority date: 2015-04-02
Filing date: 2016-03-24
Publication date: 2016-10-06
Also published as: EP3075961A1; EP3262282A1; CN107438702A

Abstract

The invention relates to a guide vane assembly (1) comprising at least partially resilient brackets (25; 31; 34), each of which has some tolerance between a web (7) of a guide vane (4) and an inner ring (3) of the guide vane assembly (1), the web (7) being located between a boot (8) and an airfoil (6) of the guide vane (4).

Description

Description of vane arrangement

The present invention relates to a vane assembly comprising an outer ring, an inner ring and a plurality of extending between the outer ring and the inner ring vanes, each having a fairfoot attached to the outer ring, extending between the outer ring and the inner ring and an airfoil via a blade web connected to the blade and having hook-like having formed ^¬ th blade head which is fixed to the inner ring, the inner ring is composed of at least a first inner ring member and a second inner ring member having first inner ring member receiving grooves through which the blade webs extend therethrough, and first inner ring member and the second inner ring member define at least one receiving space between them, which connects radially inwardly to the receiving grooves and in which the

Blade heads are included.

Such vane arrangements are known in the prior art and are used in turbomachines with axial flow. For example, a vane assembly together with a blade assembly forms a stage of a compressor or a turbine, for example. FIG 16 shows a specific ^¬ matic perspective view of a known Leitschau ^¬ felanordnung 100 with an outer ring 101, an inner ring 102 and a plurality of between the outer ring 101 and the inner ring 102 extending vanes 103, each having a fixed to the outer ring 101 blade root 104, is between the outer ring 101 and the inner ring 102 extending airfoil 105 and a connected via a blade web 106 with the airfoil 105 and hook-like ^{fancy ¬} th blade head 107 have. The blade roots 104 of the vanes 103 are received from ^¬ formed Schaufelfußnuten 108 on the outer ring 101 in accordance with each and medium- attached by means of a press fit. The inner ring 102 accommodating the blade heads 107 of the guide vanes 103 is composed of a first inner ring element 109 and of a second inner ring element 110. The first inner ring member 109 includes not shown receiving grooves through which the blade webs 106 extend therethrough, the blade heads 107 are disposed in an annular receiving space 111 which is defined between the first inner ring member 109 and the second inner ring member 110 and radially inwardly to the Connecting grooves connects. The first

Inner ring element 109 and the second inner ring element 110 are screwed or welded together. The blade heads 107 are caulked in the composite of the two inner ring elements 109 and 110 in order to compensate for manufacturing inaccuracies and to achieve a positive fit of the blade heads 107 within the receiving space 111. In this caulking, it comes to deformation of the inner ring 102 on the one hand and the blade heads 107 on the other. The caulking described has a number of disadvantages. First, the caulking causes a very rigid connection of the composite and is therefore vulnerable with respect to crack formation and wear ^¬. The causes of this damage are vibrations, thermal stresses and gas forces that occur during operation with the turbomachine. Secondly, the Verstemmgeometrien lie directly in the flow channel and can thus interfere with the flow of the medium, which is currency ^¬ rend the operation of the turbine engine passed through the Leitschaufelan ^¬ regulatory 100th This can result, for example, a reduction of the efficiency. Another

Disadvantage is that the caulking is carried out partly manually or semi-manually. Accordingly, a uniform process control or process monitoring due to the strong dispersion of manufacturing parameters is possible only with great effort. It can also lead to uneven loads of component composite, since the caulking done sequentially and not simultaneously. In addition, reproducibility is limited. Also let It is difficult to replace worn vanes 103 with new vanes during maintenance work due to caulking because the geometry of inner race 102 is plastically deformed in the region of the caulkings, which can cause great problems in the installation of new vanes.

Furthermore, from EP 2 194 230 AI an alternative to

Stemming known, according to which clamping sleeves are provided for resilient mounting of the guide vane heads on the inner ring. These sit in laterally open holes whose

However, production seems quite complex. Further

disadvantageous appears the comparatively small travel of the clamping sleeves. Also, their assembly is difficult because, in order to obtain a sufficient spring action, they may need to be preloaded first before they mounted at

Guide vane heads in the laterally open holes

can be used. Based on this prior art, it is an object of the present invention to provide an alternative vane arrangement 100 of the type mentioned above, which has improvements in particular with regard to the assembly or manufacturing costs, process stability and the attachment of the guide vane heads on the inner ring.

To achieve this object, the present invention provides a vane assembly of the type mentioned, which is characterized in that brackets are provided, which comprise the blade heads, and that the brackets

Have limbs which engage in the receiving grooves and are resiliently supported within the receiving grooves to generate a bias against both the corresponding guide vane and against the first inner ring member. A significant advantage of the guide vane arrangement according to the invention is that the guide vanes, thanks to the clamps, which are preferably made of spring steel, are fastened in a simple manner to the inner ring with resilient elastic elements. let wegungsspiel and a very high reproducibility Fixed To ^¬ gen. Just as easily, the guide vanes can also be exchanged again in case of service. In addition, due to the elastic attachment provided by the clamps, a damping effect occurs which is conducive to increasing the life of the vane assembly. Another advantage is that the stresses caused by the elastic fasteners are uniform over the component composite. In addition, the flow contour of the vane assembly according to the invention is not affected by the recorded between the first inner ring member and the second inner ring member brackets, so a reduction of the efficiency of the turbine engine is not to be ^¬ fear.

According to one embodiment of the present invention, the clamps are substantially U-shaped and mountable by radially oriented movement on the blade heads, resulting in a simple and inexpensive to manufacture clamp assembly. Also prevents this configuration that legs of the brackets can get into the flow channel, for example, due to vibration. Another important advantage of the preferred embodiment is the simplified shape of the receiving groove and the assembly of the brackets without special auxiliary tools, even with larger travel. In addition, the second inner ring segment covers the radially inwardly facing side of the first inner ring segment. At the same time, the vane heads and brackets are also covered, so that

the latter are effectively secured against accidental loss.

Preferably, the legs of the brackets are provided with protruding projections, via which the spring elasticity of the brackets can be realized.

Advantageously, the projections formed in the form of beads. Such beads can be finished with little effort. The projections may be circular, elliptical, annular, rectilinear or wavy, to name just a few examples. The blade heads in the form of grooves having formed ^¬ th and each provided a subregion of a clip essentially positively receiving recesses that prevent accidental loosening of the clamps preferably in axial direction are beneficial. Preferably, the depth of each recess is slightly greater than the thickness of the clip so that the portion of a clip received by a recess does not project outwardly beyond the clip.

According to one embodiment of the present invention define ren the first inner ring member and the second inner Ringele ^¬ management support portions which engage existing recesses of the guide vanes in between the blades and the hook-type blade heads which are in particular defined by the hook-like shape of the blade heads. In this way, a secure hold of the blade heads between the inner ring elements is realized.

Advantageously, the first inner ring element and the second inner ring element are assembled in the axial direction, resulting in a simple mountability.

The first inner ring element and the second inner ring element are preferably provided with axial contact surfaces arranged opposite one another, which are provided on the one hand with at least one projection and on the other hand with at least one corresponding recess which receives the at least one projection to produce a positive locking. Thanks to such a design of the contact surfaces, a defined relative positioning of the inner ring elements is achieved by the engaging projections and depressions.

Advantageously, the first inner ring element and the second inner ring element are welded together. According to one embodiment of the present invention, the first inner ring element and / or the second inner ring element is / are composed of individual mutually fastened ring segment sections.

To achieve the aforementioned object of the products contained ^¬ constricting invention also proposes an at least partially ^spring-¬ elasticated clamp for reducing a motion clearance between a blade ridge of a guide vane which is disposed between a blade head and a blade of the vane, and an inner ring to use a Leit ^¬ blade ^assembly , in particular a guide vane ^assembly according to the invention.

Other features and advantages of the present invention will become apparent from the following description of a vane assembly according to one embodiment of the present invention with reference to the accompanying drawings.

This is / are

1 shows a schematic front view of a half Leit ^¬ blade assembly according to an embodiment of the present invention;

FIG. 2 is a schematic perspective sectional view showing a portion of the vane assembly shown in FIG. 1; FIG.

3 is an enlarged front view of the in FIG 2 with

Reference numeral III designated section;

4 shows perspective views of 10, the individual items to show ^¬ during assembly of Darge ^¬ presented in FIG 1 vane assembly; 11 shows a perspective view of a clamp of the m FIG. 1 illustrated guide vane arrangement;

12 shows a perspective view of a clip with

alternative construction;

13 shows a cross-sectional view along the line XIII-XIII in FIG 12;

14 is a perspective view of another clip of alternative construction;

FIG. 15 shows a cross-sectional view along the line XV-XV in FIG

FIG. 14 and FIG

16 is a schematic perspective sectional view showing a portion of a known vane assembly.

Figures 1 to 15 show a vane assembly 1 according to an embodiment of the present invention or components thereof. The vane assembly 1 comprises as main components an outer ring 2, an inner ring 3 and a plurality of extending between the outer ring 2 and the inner ring 3 vanes 4, each having a fixed to the outer ring 2 blade root 5, extending between the outer ring 2 and the inner ring 3 airfoil 6 and have a connected via a blade web 7 with the blade 6 and hook-like design blade head 8, which is fixed to the inner ring 3.

Outer ring 2 and inner ring 3 are known to be arranged concentrically to a virtual machine axis 14, which is to serve as a reference axis for the terms "radial" and "axial". The outer ring 2 is provided along its inner periphery with a plurality of Schaufelfußaufnahmenuten 9 in which the blade roots 5 of the guide vanes 4 are received and fixed by means of a press fit.

The inner ring 3 is composed of a first inner ring element 10 and of a second inner ring element 11, wherein both the first inner ring element 10 and the second inner ring element 11 in the present case consist of a plurality of ring segments. The first inner ring member 10 has a T-shaped Wesentli ^¬ chen cross-section which a radially inwardly extending support legs 12 and located in

Substantially axially extending receiving leg 13 defi ^¬ ned. The receiving leg 13 has a number of guide vanes 4 corresponding number of grooves 14, which are equally spaced in the circumferential direction and serve to accommodate the blade webs 7. The groove bottom of each receiving groove 14 is spaced from the support leg 12 and forms a support portion 15. At its free end of the receiving leg 13 defines between the individual receiving grooves 14 axial contact surfaces 16 which are provided with circumferentially extending and axially projecting projections 17. The second inner ring element 11 has a substantially L-shaped cross-section which defined an axially extending support leg 18 and a radially outwardly extending retaining limbs 19 defi ^¬ which is provided at its free end with a circumferentially encircling support portion 20 projecting axially and in the direction of the support leg 12 of the first inner ring element 10. The support portion 20 forms an axial con ^¬ tact surface 21 which is provided with a circumferentially circumferential recess 22 which is formed corresponding to the projections 17 of the first inner ring member 10 and in engagement therewith. Defining the first inner ring element 10 and the second inner ring member 11 between them an annular receiving space 23, the radially inwardly at ^¬ joins the receiving grooves 14 of the first inner ring element 10 and in which the blade heads 8 of the guide vanes 4 are positively held, with the supporting portions 15 of the first inner ring element 10 and the support portion 20 of the second inner ring element 11 in between the Schaufelblät ^¬ tern 6 and the hook-like blade heads 8 existing training recesses 24 of the vanes 4 engage.

The blade webs 7 are fixed in the associated receiving grooves 14 of the first inner ring element 10 in each case using a clamp 25 which is presently made of spring steel ^¬ made and U-shaped. The brackets 25 umfas ^¬ sen a base leg 26 and two, which are nachfol ^¬ quietly referred to as the side legs of the base leg 26 outwardly extending leg 27 and 28th The side legs 27, 28 are each provided with inwardly projecting projections 29, which are designed as straight beads extending transversely to the extension direction of the side legs 27 and 28 over the entire length of the side legs 27 and 28. The free ends of the side legs 27 and 28 are provided with bevels. Each clip 25 is mounted from above on a blade head 8 that the Basisschen ^¬ angle substantially positively received in a groove-shaped recess 30 of the blade head 8 and the side legs 27 and 28 engage in the grooves 14, within which they produce a Pretension against both the blade webs 7 and against the first

Support inner ring element 10 resiliently.

For assembly, the vane assembly 1 in a first step, the vanes 4 are fixed to the outer ring 2, in- which the blade roots are inserted into the associated Schaufelfußaufnahme ^¬ grooves 9 of the outer ring 2 and fastened by means of press fits. In a further step, the first inner ring element 10 of the inner ring 3 is pushed axially onto the guide vanes 4 in such a way that the individual blade webs 7 of the guide vanes 4 are inserted into the receiving grooves 14 of the first inner ring element 10 until it engages the support sections 15 of the first inner ring element 10 anschla ^¬ gen, see FIG 4. In a further step, restrain or be 5, as shown in FIG. 5, from above in each case-but with respect to the virtual machine axis 14 radially outwards-are pushed onto the blade heads 8 until the two side limbs 27 and 28 of the clamp 25 engage in the

Receiving groove 14 are inserted and the base leg 26 of the clip 25 is received in the provided on the blade head 8 recess 30. Figures 6 and 7 show a bracket 25 in the assembled state, in which the side legs 27 and 28 both against the vane 4 and against the opposite walls of the first

Support inner ring element 10. Thanks to the projections 29 while a resilient seat of the blade web 7 is achieved within the grooves 14 of the first inner ring member 10. In a subsequent step, the second inner ring element 11 shown in FIG 8 is axially on the first

Inner ring member 10 is pushed until the support portion 20 of the second inner ring member 11 in the associated

Recess 24 of the guide vanes 4 is inserted and the projections 17 of the first inner ring member 10 with the formed on the second inner ring member 11 recess 22 in

Are engaged. 9 shows the second inner ring element 11 in the mounted state. In a last step, the first inner ring member 10 and the second inner ring member 11 are welded together, which is not shown in more detail in the figures.

A significant advantage associated with the described vane arrangement 1 is that the guide vanes 4, thanks to the clamps 25, can be fastened in a simple manner to the inner ring with elastic movement play and a very high reproducibility. Likewise, the guide vanes 4 can also be replaced again in case of service. In addition, due to the elastic attachment achieved by the bracket 25, a damping effect occurs, which is conducive to an increase in the life of the vane assembly 1. Another advantage is that due to the brackets 25 of the composite component is evenly loaded. In addition, the flow Contour of the guide vane assembly 1 according to the invention is not affected by the recorded between the first inner ring member 10 and the second inner ring member 11 brackets 25, which is why a reduction in the efficiency of the turbomachine is not to be feared.

Figures 12 to 15 show alternative embodiments of brackets 31 and 33, which differ only with respect to the projections 32 and 34 from the previously described bracket 25, for which reason the same component areas are designated by the same reference numerals. In the clamp 31 shown in FIGS. 12 and 13, the projections 32 are elliptical in shape, the ellipse longitudinal axis being arranged transversely to the extension direction of the side legs 27 and 28. In the bracket 33 shown in Figs. 15 and 15, the projections 34 are provided in a waveform.

Although the invention in detail by the preferred embodiment has been illustrated and described in detail, the invention is not limited ^¬ by the disclosed examples and other variations can be derived therefrom by the skilled artisan without departing from the scope of the invention.

Claims

claims

A vane assembly (1) comprising an outer ring (2), an inner ring (3) and a plurality of between the outer ring

(2) and the inner ring (3) extending vanes (4), each having a on the outer ring (2) fixed blade root (5), a between the outer ring (2) and the inner ring

(3) extending blade (6) and a via a blade web (7) with the blade (6) connected and hook-like blade head (8) which is fixed to the inner ring (3),

wherein the inner ring (3) is composed of at least a first inner ring element (10) and a second inner ring element (11), the first inner ring element (10) has receiving grooves (14) through which blade webs (7) extend, and the first Inner ring member (10) and the second inner ring member (11) between them define ^{¬ at} least one receiving space (23) which connects radially inwardly of the receiving grooves (14) and in which the blade heads (8) are accommodated,

characterized in that

Clamps (25; 31; 34) are provided, which comprise the blade ^¬ heads (8), and

in that the brackets (25; 31; 34) have legs (27, 28) which engage in the receiving grooves (14) and within the receiving grooves (14) to generate a bias against both the vane (4) and the first Support inner ring element (10) resiliently.

2. vane arrangement (1) according to claim 1,

characterized in that

the brackets (25; 31; 34) are substantially U-shaped and can be mounted on the blade heads (8) by a movement oriented in the radial direction.

3. vane arrangement (1) according to one of the preceding claims,

characterized in that

the legs (27, 28) of the clamps (25; 31; 34) with projecting projections (29; 32; 34) for realizing the

Spring elasticity are provided.

4. vane arrangement (1) according to claim 3,

characterized in that

the projections (29; 32; 34) are in the form of beads.

5. vane arrangement (1) according to claim 3 or 4,

characterized in that

the projections (29; 32; 34) are circular, elliptical, annular, rectilinear or wavy.

6. vane arrangement (1) according to one of the preceding claims,

characterized in that

the blade heads (8) with groove - shaped and depending ^¬ Weil a portion of a clip (25, 31, 34) in

Substantially positively receiving recesses (30) are provided.

7. vane arrangement (1) according to one of the preceding claims,

characterized in that

the first inner ring element (10) and the second inner ring element (11) define support sections (15, 20) which engage recesses (24) in the guide vanes (4) between the blade leaves (6) and the hook-like blade heads (8).

8. vane arrangement (1) according to one of the preceding claims,

characterized in that

the first inner ring element (10) and the second inner ring element (11) are assembled in the axial direction.

9. vane arrangement (1) according to claim 8,

characterized in that

the first inner ring element (10) and the second inner ring element (11) with opposing axial

Contact surfaces (16, 21) are provided, which are provided for generating a positive connection on the one hand with at least one Vor ^¬ jump (17) and on the other hand with at least one corres ^¬ dierenden recess (22) which receives the at least one projection (17).

10. vane arrangement (1) according to one of the preceding claims,

characterized in that

the first inner ring element (10) and the second inner ring ^¬ element (11) are welded together.

11. vane arrangement (1) according to one of the preceding claims,

characterized in that

the first inner ring member (10) and / or the second inner ^¬ ring element (11) are composed of individual ring segment portions secured together / is.

12. Use of an at least partially elastically designed clamp (25, 31, 34) for reducing a play between a blade web (7) of a guide ^¬ blade (4) between a blade head (8) and an airfoil (6) of the guide vane ( 4), and an inner ring (3) of a vane assembly,

in particular a guide vane assembly (1) according to one of the preceding claims.