CLOSING ASSEMBLY FOR CLOSING A BLADE RING, ASSOCIATED BLADE SUPPORTS, TURBOMACHINE, AND METHOD FOR INSERTING A CLOSING ASSEMBLY

Abstract

A closing assembly for closing a blade ring inserted into a circumferential T-groove of a blade support of a turbomachine, having two insertion elements, each has a C-shaped basic form having a resting leg, retention leg, and connection leg connecting the resting leg and the retention leg and is designed to reach around a ridge of the T-groove. The resting leg reaches over the ridge and the retention leg reaches under the ridge, and an intermediate element, is positioned between the insertion elements to prevent the insertion elements from moving to the center of the T-groove. The intermediate element reaches below the retention legs of the insertion elements in the assembled state, and a positioning element is associated with the intermediate element, which is supported between the groove base of the T-groove and the intermediate element and to position the intermediate element at a desired distance from the groove base.

Claims

1. A closing assembly for closing a blade ring which is inserted into an encircling T-groove of a blade support of a turbomachine, comprising: two insert elements which each have a C-shaped basic shape having a resting leg, a retention leg, and a connection leg that connects the resting leg to the retention leg and which each are configured for encompassing one web of the T-groove, wherein the resting leg engages above the web and the retention leg engages below the web, and having an intermediate element that is positionable between the insert elements and is configured to prevent the latter from moving toward the center of the T-groove, wherein the intermediate element in the fitted state is configured to engage below the retention legs of the insert elements, and the intermediate element is assigned positioning means which are configured to be supported between the groove base of the T-groove and the intermediate element and to position the intermediate element at a desired spacing from the groove base.

2. The closing assembly as claimed in claim 1, wherein in each case one protrusion which projects from the connection leg in a direction that is counter to the resting leg of the insert element is provided on the insert elements.

3. The closing assembly as claimed in claim 2, wherein an upper side of the protrusion aligns with an upper side of the resting leg.

4. The closing assembly as claimed in claim 1, wherein the intermediate element has a substantially T-shaped basic shape, having a longitudinal web that extends in a longitudinal direction, and a transverse web that extends transversely to the longitudinal web and is configured to engage below the retention legs of the insert elements, wherein the longitudinal web protrudes from the transverse web in particular in a centric manner.

5. The closing assembly as claimed in claim 4, wherein the longitudinal web at the free end thereof in the transverse direction of the T-groove has a width of such a manner that said longitudinal web is positionable between the protrusions of the insert elements hat are inserted into the T-groove so as to bear on said protrusions or to have a clearance therefrom, in order to prevent the insert elements in the upper regions thereof from moving toward the center of the T-groove.

6. The closing assembly as claimed in claim 5, wherein the width of the longitudinal web of the intermediate element decreases in a conical manner in the direction of the free end of said longitudinal web.

7. The closing assembly as claimed in claim 4, wherein the longitudinal web of the intermediate element has a height of such a manner that the free end of said longitudinal web terminates so as to be flush with the protrusions of the two insert elements in the fitted state.

8. The closing assembly as claimed in claim 4, wherein the sum of the heights of one protrusion and of the intermediate element is smaller than the depth of the T-groove, such that the free end of the longitudinal web is engaged above by a protrusion of an inserted insert element when the intermediate element in the T-groove is displaced in the transverse direction in such a manner that the longitudinal web comes to bear on the connection leg of the insert element.

9. The closing assembly as claimed in claim 4, wherein the width of the transverse web of the intermediate element in the transverse direction is larger than the clear spacing between the two mutually opposite webs of the T-groove in which the closing assembly is to be installed.

10. The closing assembly as claimed in claim 4, wherein the length of the intermediate element in the longitudinal direction of the T-groove corresponds to the length of the insert elements.

11. The closing assembly as claimed in claim 4, wherein steps are configured on both sides of the longitudinal web in a transitional region between the longitudinal web and the transverse web of the intermediate element, said steps in each case being assigned to the insert elements so as to prevent the insert elements in the lower regions thereof from moving toward the center of the T-groove, wherein the steps are configured in such a manner that said steps are positionable between the connection legs of the insert elements that are inserted into the T-groove, so as to bear on said connection legs or to have a clearance therefrom.

12. The closing assembly as claimed in claim 4, wherein free spaces remain between the protrusions of the insert elements and the steps of the intermediate element.

13. The closing assembly as claimed in claim 1, further comprising: a threaded bolt which is screw-fittable in such a manner into a threaded bore that penetrates the intermediate element in the longitudinal direction thereof that said threaded bolt projects in the direction of the groove base and is capable of being brought to bear on the latter so as to set the radial spacing of the intermediate element from the groove base is provided as a positioning means.

14. The closing assembly as claimed in claim 13, wherein the threaded bolt has a length which corresponds to the depth of the T-groove.

15. A blade support comprising: an encircling T-groove in which a plurality of blades and intermediate pieces are disposed in an alternating manner, and a closing assembly as claimed in claim 1 is inserted into an intermediate space between two blades.

16. A turbomachine comprising: at least one blade support as claimed in claim 15.

17. A method for inserting a closing assembly as claimed in claim 1 into an encircling T-groove of a blade support, said method comprising the following steps: inserting the intermediate element into the T-groove in such a manner that the former bears on a groove base of the T-groove; displacing the intermediate element in the T-groove in the transverse direction of the latter such that the former comes to bear on a web of the T-groove; inserting an insert element into the T-groove in such a manner that the former encompasses a web of the T-groove; displacing the intermediate element in the T-groove in the transverse direction of the latter such that the intermediate element comes to bear on the connection leg of the insert element that is inserted into the T-groove; inserting the further insert element into the T-groove in such a manner that the former encompasses the other web of the T-groove; displacing the intermediate element to the center of the T-groove; positioning the intermediate element by way of the positioning means so as to be spaced apart from the groove base in such a manner that the intermediate element engages below the retention legs of the insert elements and prevents the two insert elements from moving toward the center of the T-groove.

18. The closing assembly as claimed in claim 2, wherein said protrusion is disposed in the upper region of the connection leg so as to be level in height with the resting leg.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Further features and advantages of the present invention will become evident by means of the following description of an embodiment of the closing assembly according to the invention with reference to the appended drawing in which:

[0030] FIG. 1 shows a schematic cross-sectional view of a closing assembly according to one embodiment of the present invention;

[0031] FIG. 2 shows a perspective exploded view of the closing assembly illustrated in FIG. 1;

[0032] FIG. 3 shows a schematic cross-sectional view of the closing assembly illustrated in FIG. 2, when the intermediate element is being inserted;

[0033] FIG. 4 shows a schematic cross-sectional view of the closing assembly illustrated in FIG. 2, once the intermediate element has been inserted;

[0034] FIG. 5 shows a schematic cross-sectional view of the closing assembly illustrated in FIG. 2, while the first insert element is being inserted;

[0035] FIG. 6 shows a schematic cross-sectional view of the closing assembly illustrated in FIG. 2, while the second insert element is being inserted;

[0036] FIG. 7 shows a schematic cross-sectional view of the closing assembly illustrated in FIG. 2, prior to the positioning means being inserted;

[0037] FIG. 8 shows a cross-sectional view of the closing assembly illustrated in FIG. 2, having the positioning means inserted; and

[0038] FIG. 9 shows a schematic cross-sectional view of the closing assembly illustrated in FIG. 2, having the intermediate element positioned.

DETAILED DESCRIPTION OF INVENTION

[0039] FIGS. 1 and 2 show an embodiment of the closing assembly 1 according to the invention. Said closing assembly 1 is inserted into an encircling T-groove 2 of a blade support of a turbomachine, so as to fill the last remaining intermediate space between two blades of a blade ring to be formed and, on account thereof, to close the blade ring. The blade support can be a rotor disk of a gas or steam turbine, for example.

[0040] The closing assembly 1 comprises two insert elements 3, 4 which each have a C-shaped basic shape and comprise a resting leg 5, 6, a retention leg 7, 8, and a connection leg 9, 10 that connects the resting leg 5, 6 to the retention leg 7, 8. The insert elements 3, 4 each are configured for encompassing one web 11, 12 of the T-groove 2. The resting legs 5, 6 herein respectively engage above the webs 11, 12 of the T-groove 2, while the retention legs 7, 8 engage below the webs 11, 12 of the T-groove 2.

[0041] Furthermore, one protrusion 13, 14 which is disposed so as to be level in height with the resting leg 5, 6 and projects from the connection leg 9, 10 in the direction counter to the respective resting leg 5, 6, that is to say toward the center of the T-groove, is provided on each insert element 3, 4. The upper side of the protrusion 13, 14 herein is aligned with the upper side of the resting leg 5, 6. On account thereof, an overall smooth flow-facilitating upper side of the insert elements 3, 4 results.

[0042] The closing assembly 1 furthermore comprises an intermediate element 15 which is positioned in the T-groove 2 between the insert elements 3, 4. The intermediate element 15 is configured to prevent the two insert elements 3, 4 from moving into the center of the T-groove 2. The intermediate element 15 has a substantially T-shaped basic shape, having a longitudinal web 16, a transverse web 17 which extends in the transverse direction of the T-groove 2 being disposed on the lower end of said longitudinal web 16.

[0043] The transverse web 17 is configured to engage below the retention legs 7, 8 of the insert elements 5, 6. Specifically, the width of the transverse web 17 of the intermediate element 15 is larger than the clear spacing between the two mutually opposite webs 11, 12 of the T-groove 2. Consequently, the intermediate element 15 cannot leave the T-groove 2 without being pivoted about an axis that runs in the circumferential direction of the T-groove 2. The length of the intermediate element 15 in the circumferential direction of the T-groove 2 corresponds to the clear spacing between two adjacent blades which are inserted into the T-groove 2. Consequently, the intermediate element 15 in the installed state cannot rotate about an axis that runs in the circumferential direction.

[0044] The longitudinal web 16 protrudes from the transverse web 17 in a centric manner and has a length of such a manner that the free end of said longitudinal web 16 in the fitted state terminates so as to be flush with the protrusions 13, 14 of the insert elements 3, 4. This provides a smooth flow-facilitating upper side of the fitted closing assembly 1.

[0045] The width of the longitudinal web 16 of the intermediate element 15 decreases in a conical manner from the transverse web 17 in the direction of the free end of said longitudinal web 16, and at said free end has a width of such a manner that said longitudinal web 16 is positionable between the protrusions 13, 14 of the insert elements 5, 6 that are inserted into the T-groove 2 so as to bear on said protrusions 13, 14 or to have a clearance therefrom. Said longitudinal web 16 in this position prevents the upper regions of the insert elements 5, 6 from moving toward the center of the T-groove 2.

[0046] Steps 18, 19 which are in each case assigned to the insert elements 3, 4 are configured on both sides of the longitudinal web 16 between the longitudinal web 16 and the transverse web 17 of the intermediate element 15. Said steps 18, 19 prevent the lower regions of the insert elements 3, 4 from moving into the center of the T-groove 2. To this end, the entire width of the steps 18, 19 is chosen in such a manner that the steps 18, 19 are positioned between the connection legs 9, 10 of the inserted insert elements 5, 6 so as to bear on said connection legs 9, 10 or to have a clearance therefrom.

[0047] The summed length of a protrusion 13, 14 and of the intermediate element 15 herein is smaller than the depth of the T-groove 2 such that the free end of the longitudinal web 16 can in each case be engaged above by the protrusions 13, 14 of the inserted insert elements 5, 6 when the intermediate element 15 in the T-groove 2 is displaced in the transverse direction of the latter in such a manner that the longitudinal web 16 comes to bear on the connection legs 9, 10 of the insert elements 5, 6.

[0048] In the fitted state of the closing assembly 1, free spaces remain between the connection legs 9, 10 of the insert elements 3, 4 and the longitudinal web 16 of the intermediate element 15, the size of said free spaces being determined substantially by the protrusions 13, 14 and the steps 18, 19. The free spaces that are created on both sides of the longitudinal web 16 between the protrusions 13, 14 and the steps 18, 19 are utilized during the insertion procedure to provide adequate space for inserting the subsequent insert element 3, 4 between the longitudinal web 16 and the web 11, 12 by displacing the intermediate element 15 temporarily under the insert element 3, 4 inserted first.

[0049] A threaded bore 20 which penetrates the intermediate element 15 in the longitudinal direction of the latter is provided in the longitudinal web 16 of the intermediate element 15. A threaded bolt 21 is screw-fitted into this threaded bore 20. The threaded bolt 21 has a length which corresponds to the depth of the T-groove 2.

[0050] In this way, the threaded bolt 21 does not protrude from the T-groove 2 when said threaded bolt 21 is supported on the groove base 22 of the T-groove 2, and moreover in the fitted state of the closing assembly terminates so as to be flush with the longitudinal web 16 of the intermediate element 15.

[0051] FIGS. 3 to 9 show the closing assembly 1 in individual stages of the insertion method.

[0052] First, the intermediate element 15 is inserted into the intermediate space that remains between two blades. To this end, pivoting the intermediate element 15 about an axis that is disposed in the circumferential direction of the T-groove 2 is required since the width of the transverse web 17 is larger than the clear spacing between the mutually opposite webs 11, 12 of the T-groove 2 (FIG. 3).

[0053] Once the transverse web 17 of the intermediate element 15 has passed the constriction between the two webs 11, 12, the intermediate element 15 is pivoted in such a manner that the transverse web 17 of the latter comes to bear on the groove base 22 (FIG. 4).

[0054] The intermediate element 15 in the T-groove is now displaced in the transverse direction, so as to provide adequate space for inserting an insert element 3, 4 between a web 11, 12 and the longitudinal web 16 of the intermediate element 15 (FIG. 5).

[0055] The first insert element 3, 4 thereafter is positioned in the T-groove 2 in such a manner that the former encompasses the first web 11, 12. The intermediate element 15 in the T-groove 2 is displaced in the transverse direction until the longitudinal web 15 of said intermediate element 15 comes to bear on the connection leg 9, 10 of the positioned insert element 3, 4. This is possible because the added lengths of the protrusion 13, 14 and of the intermediate element 15 are chosen such that the free end of the longitudinal web 15 fits under the protrusion 13, 14, and that the step 18, 19 also finds space under the retention leg 7, 8 of the insert element 3, 4. In this position of the intermediate element 15 adequate space is created for the further insert element 3, 4 to be inserted into the T-groove 2 (FIG. 6).

[0056] When the further insert element 3, 4 has been positioned so as to encompass the further web 11, 12, the intermediate element 15 is displaced into the center of the T-groove 2 (FIG. 7).

[0057] The threaded bolt 21 is now screw-fitted into the threaded bore 20 of the intermediate element 20 until the threaded bolt 21 is supported on the groove base 22 (FIG. 8).

[0058] Further screwing-in of the threaded bolt 21 leads to the intermediate element 15 being lifted from the groove base 22 while forming a spacing. The threaded bolt 21 is finally screw-fitted so far that the longitudinal web 16 terminates so as to be flush with the insert elements 3, 4, on account of which the steps 18, 19 are disposed between the lower regions of the connection legs 9, 10 of the insert elements 3, 4, and the free end of the longitudinal web 16 is positioned between the protrusions 13, 14 (FIG. 9).

[0059] In this fitted state of the closing assembly, the two insert elements 3, 4 in the upper and the lower region thereof are now prevented from moving into the center of the T-groove 2. Simultaneously, the intermediate element 15 is prevented by the protrusions 13, 14 and the steps 18, 19 from moving in the transverse direction of the T-groove 2. To this end, it is not necessary for the intermediate element 15 to be pressed with a great force below the retention legs 7, 8 of the insert elements 3, 4, while stressing the threaded bolt 21 and the threaded bore 20. This reduces the risk of overstressing the positioning means 21 and of the latter being damaged by virtue of material fatigue.

[0060] While the invention has been illustrated and described in detail by way of the preferred exemplary embodiment, the invention is not limited by the examples disclosed, and other variants can be derived therefrom by a person skilled in the art without departing from the scope of protection of the invention.