Axially divided turbomachine inner ring

Abstract

An axially divided inner ring is provided for fastening to, in particular adjustable, guide vanes (50) of a turbomachine, in particular a compressor or turbine stage of a gas turbine, which includes a first partial ring (10) and a second partial ring (20), which is supported in the axial direction directly or indirectly on two axially facing support surfaces (11, 12) of the first partial ring (10) and is fixed on the first partial ring (10) in the radial direction with the aid of multiple alignment pins (40) distributed in the circumferential direction.

Claims

1. An axially divided inner ring for fastening to guide vanes of a turbomachine, the inner ring comprising: a first partial ring; and a second partial ring axially divided from the first partial ring and supported in an axial direction directly or indirectly on two axially facing support surfaces of the first partial ring and fixed on the first partial ring in a radial direction; and wherein the second partial ring is clamped in the axial direction between the two facing support surfaces of the first partial ring.

2. The inner ring as recited in claim 1 wherein the second partial ring has at least one annular groove for reducing a stiffness in the axial direction.

3. The inner ring as recited in claim 1 wherein the second partial ring contacts the two facing support surfaces of the first partial ring, or a spring is situated between the second partial ring and at least one of the two facing support surfaces for clamping the second partial ring between the support surfaces.

4. The inner ring as recited in claim 1 wherein at least one of the alignment pins is inserted into a blind hole-recess or through-recess in the first or second partial ring in a frictionally engaged manner or is secured in the axial direction by a securing means fastened on at least one of the partial rings.

5. The inner ring as recited in claim 4 wherein the securing means includes a spring or a wedge.

6. The inner ring as recited in claim 4 wherein the securing means is a spring.

7. The inner ring as recited in claim 1 wherein a contact surface of the second partial ring rests on a mating surface of the first partial ring in the radial direction.

8. The inner ring as recited in claim 7 wherein the contact surface is radially on an outside of the mating surface.

9. The inner ring as recited in claim 1 wherein at least one of the support surfaces is situated on a radial flange or in a radial groove of the first partial ring.

10. The inner ring as recited in claim 1 wherein the first or second partial ring is segmented in the circumferential direction.

11. The inner ring as recited in claim 1 further comprising a radial seal integrally formed with the first or second partial ring.

12. The inner ring as recited in claim 1 further comprising a radial seal fastened on the first or second partial ring.

13. The inner ring as recited in claim 1 wherein the first and second partial rings together form blind hole-recesses or through-recesses for fastening to the guide vanes.

14. The inner ring as recited in claim 13 wherein the recesses or the through-recesses are coated, as are the guide vanes.

15. The inner ring as recited in claim 13 further comprising bushings in the recesses for supporting the guide vanes.

16. A guide baffle for a turbomachine comprising the axially divided inner ring as recited in claim 1 and the guide vanes, the inner ring being fastened to the guide vanes.

17. The guide baffle as recited in claim 16 wherein the guide vanes are adjustable.

18. A turbomachine comprising at least one compressor or turbine stage having the axially divided inner ring as recited in claim 1.

19. A gas turbine comprising the turbomachine as recited in claim 18.

20. A compressor or turbine stage of a gas turbine comprising the axially divided inner ring as recited in claim 1.

21. A method for assembling an axially divided inner ring as recited in claim 1, the second partial ring being clamped in the axial direction between the two facing support surfaces of the first partial ring and fixed in the radial direction on the first partial ring with the aid of the alignment pins.

22. A method for manufacturing an axially divided inner ring as recited in claim 1 wherein the first or second partial ring is machined, in particular recesses for the alignment pins or guide vanes being manufactured or the partial ring being segmented, while at least one, in particular finished, of the support surfaces of the first partial ring and an, in particular, finished bearing surface of the second partial ring being situated on top of the other and pressed against each other.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a part of a guide baffle of a turbomachine, including an inner ring according to one embodiment of the present invention, in a meridian section;

(2) FIG. 2 shows a part of a guide baffle of a turbomachine, including an inner ring according to another embodiment of the present invention, in a representation corresponding to FIG. 1;

(3) FIG. 3 shows a part of a guide baffle of a turbomachine, including an inner ring according to another embodiment of the present invention, in a representation corresponding to FIGS. 1 and 2;

(4) FIG. 4 shows a highly schematicized cross-section to show the circumferential nature of the turbomachine 100.

DETAILED DESCRIPTION

(5) FIG. 1 shows part of a guide baffle of a turbomachine 100, including an inner ring according to one embodiment of the present invention in a meridian section, in which a rotation or (main) machine axis is situated (horizontally in FIG. 1).

(6) The inner ring includes a first partial ring 10 and a second partial ring 20 and is thus divided (in two) axially or in the axial direction (horizontally in FIG. 1). The inner ring or partial rings 10, 20 is/are (each) segmented into two halves in the circumferential direction, as shown highly schematicized in FIG. 4.

(7) A radial seal 19 is situated radially inwardly (at the bottom of FIG. 1) on first partial ring 10.

(8) First and second partial rings 10, 20 together form blind hole-like bores 52, in which journals 51 of adjustable guide vanes 50 are rotatably supported, in one embodiment directly and in another embodiment via bushings, shown schematically in FIG. 3 by dotted lines.

(9) Second partial ring 20 is fixed on first partial ring 10 in the radial direction (vertically in FIG. 1) with the aid of multiple alignment pins 40 distributed in the circumferential direction, which are inserted in a frictionally engaged manner into through-bores 24 in second partial ring 20 and partially therethrough into blind hole-like bores 14 in first partial ring 10.

(10) Second partial ring 20 is supported in the axial direction on two axially facing support surfaces 11, 12 of first partial ring 10, supporting surface 12 being situated in a radial groove 13 of first partial ring 10.

(11) A bearing surface 21 of second partial ring 20 contacts support surface 11 of first partial ring 10, while a spring means 30 is situated between second partial ring 20 and other support surface 12, through or via which second partial ring 20 is supported in the axial direction on other support surface 12 of the two axially facing support surfaces 11, 12 of first partial ring 10 and is clamped hereby therebetween in the axial direction.

(12) This spring means 30 is partially situated or fastened in a frictionally engaged manner in groove 13 of first partial ring 10 and partially in a groove 23 of second partial ring 20 and thus simultaneously acts as a securing means which secures alignment pins 40 in the axial direction.

(13) A contact surface 25 of second partial ring 20 rests from the radial outside (from the top in FIG. 1) on a mating surface 15 of first partial ring 10.

(14) To manufacture the inner ring, support surface 11 and mating surface 15 of first partial ring 10 and bearing surface 21 and contact surface 25 of second partial ring 20 are initially machine-finished, situated one on top of the other, and both partial rings 10, 20 are clamped to each other in the axial direction with the aid of clamping means, which are not illustrated, so that support surface 11 and bearing surface 21 are pressed against each other.

(15) In this state bores 14, 24, 52 are finished and the two partial rings 10, 20 are each segmented into two halves in the circumferential direction.

(16) The two partial rings 10, 20 are subsequently detached from each other again and pushed against each other counterclockwise in the axial direction for assembly, whereby they surround bearing journals 51 of guide vanes 50. Alignment pins 40 are then inserted and spring means 30 subsequently fastened in grooves 13, 23.

(17) FIG. 2 shows a part of a guide baffle of a turbomachine, including an inner ring according to another embodiment of the present invention, in a representation corresponding to FIG. 1. Corresponding features are identified by identical reference numerals, so that reference is hereby made to the preceding description and only the differences are discussed below.

(18) In the embodiment in FIG. 2, support surface 12 of first partial ring 10 is curved and situated not in a groove but on a radial collar 16, which, in turn, is situated on mating surface 15 of first partial ring 10.

(19) Second partial ring 20, which in the embodiment in FIG. 2 is supported directly on support surfaces 11, 12 of first partial ring 10, may be or become clamped therebetween, in that an axial distance between support surfaces 11, 12 is slightly shorter than an axial distance between bearing surface 21, 22 contacting them in undeformed second partial ring 20.

(20) To manufacture the inner ring, support surfaces 11, 12 and mating surface 15 of first partial ring 10 and bearing surfaces 21, 22 and contact surface 25 of second partial ring 20 are initially finished, situated one on top of the other, and both partial rings 10, 20 are clamped to each other in the axial direction with the aid of clamping means, which are not illustrated.

(21) In this state bores 14, 24, 52 are finished and the two partial rings 10, 20 are each segmented into two halves in the circumferential direction.

(22) The two partial rings 10, 20 are subsequently detached from each other again and pushed against each other counterclockwise in the axial direction for assembly, whereby they surround bearing journals 51 of guide vanes 50, the curvature of support surface 12 favoring an assembly. Alignment pins 40 are then inserted and securing means 30 subsequently fastened in grooves of first partial ring 10.

(23) FIG. 3 shows a part of a guide baffle of a turbomachine, including an inner ring according to another embodiment of the present invention, in a representation corresponding to FIGS. 1 and 2. Corresponding features are identified by identical reference numerals, so that reference is hereby made to the preceding description and only the differences are discussed below.

(24) In the embodiment in FIG. 3, support surface 12 of first partial ring 10 is flat and situated not in a groove but on a radial end flange 17, which delimits mating surfaces 15 of first partial ring 10.

(25) Second partial ring 20, which in the embodiment in FIG. 3 is also directly supported on support surfaces 11, 12 of first partial ring 10, is clamped in the axial direction therebetween with the aid of a shrink or press fit.

(26) For this purpose, it has an annular groove 26 radially on the inside for reducing its stiffness in the axial direction.

(27) To manufacture the inner ring, axially facing support surfaces 11, 12 and mating surface 15 of first partial ring 10 and the bearing surfaces (only bearing surface 21 is provided with a reference numeral in FIG. 3) and the contact surface of second partial ring 20 are finished, situated one on top of the other, and both partial rings 10, 20 are clamped to each other in the axial direction by shrinking on second partial ring 20.

(28) In this state bores 14, 24, 52 are finished and the two partial rings 10, 20 are each segmented into two halves in the circumferential direction.

(29) The two partial rings 10, 20 are subsequently detached from each other again and pushed against each other counterclockwise in the axial direction for assembly, whereby they surround bearing journals 51 of guide vanes 50, the limited radial height of end flange 17 favoring a shrinking on of second partial ring 20 for assembly. Alignment pins 40 are then inserted and securing means 30 subsequently fastened in grooves of first partial ring 10.

(30) While the description above explains exemplary embodiments, it should be pointed out that a large number of modifications are possible.

(31) In a modification indicated by the dash-dot line in FIGS. 1 through 3, securing means 30 may also be designed as a one- or multi-part wedge having a wall thickness which increases in the circumferential direction, which or whose parts is/are inserted into grooves 13, 23 in the circumferential direction and are or become fixed therein in a frictionally engaged manner.

(32) Moreover, it should be pointed out that the exemplary embodiments are only examples which are not intended to limit the scope of protection, the applications and the design in any way. Rather, the description above gives those skilled in the art a guideline for implementing at least one exemplary embodiment, various modifications being possible, in particular with respect to the function and arrangement of the described components, without departing from the scope of protection as it is derived from the claims and feature combinations equivalent to the claims.

LIST OF REFERENCE NUMERALS

(33) 10 first partial ring 11, 12 support surface 13 groove 14 bore 15 mating surface 16 collar 17 end flange 19 seal 20 second partial ring 21, 22 bearing surface 23 groove 24 bore 25 contact surface 26 annular groove 30 spring and/or securing means 40 alignment pin 50 guide vane 51 journal 52 bore 100 turbomachine