A seal ring having a plurality of overlapping seal components, and a stator assembly having the same

Abstract

The present invention relates to a sealing ring (01) for sealing a gap (19) that circumscribes a rotor axis (02) between a rear stator unit (14) at the rear side (04) and a front stator unit (15) at the front side (05). This sealing ring (01) includes an upper left sealing component (21), a lower right sealing component (24) and an upper right sealing component (23) that are positioned opposite each other with the rotor axis (02) therebetween, and a lower left sealing component (26) that is positioned opposite the rotor axis (02). Each of these four sealing components (21, 23, 24, 26) has one sealing section (31) that extends in the circumferential direction, one contact section (32) arranged at a first end, one bent section (33) arranged at the opposite end, and one overlapping section (34) adjacent to this bent section (33).

Description

Technical Field

[0001] The present invention relates to a seal ring for sealing a gap between a front stator unit and a rear stator unit in a gas turbine.

[0002] A gas turbine is formed by a plurality of segments provided successively in the axial direction. In a stationary structure, one stator ring having a plurality of fixed stator blades forms, for example, one stator unit. There is a circumferential gap between this stator unit and the front or rear stator unit. In order to avoid the inflow of high-temperature gas from the gas turbine flow path or the unacceptable outflow of cooling air through the gap, it is usually necessary to provide a seal ring in this gap.

[0003] Various structures for seal rings corresponding thereto are known from the prior art. Usually, for this purpose, a plurality of flat and segmented steel bands are used, and both sides thereof engage with adjacent stator units. Various solutions for fixing the seal ring in the circumferential direction and reducing leakage between continuous portions of the seal ring are known and effective, but there is no completely satisfactory solution.

Summary of the Invention

Problems to be Solved by the Invention

[0004] Therefore, an object of the present invention is to make available an improved solution for a seal ring that enables fixation in the circumferential direction on the one hand and minimizes leakage between individual elements of the seal ring on the other hand. In this case, it is important to enable easy and rapid assembly.

Means for Solving the Problems

[0005] The above problem is solved by an embodiment of a seal ring according to the teaching of claim 1. A stator assembly according to the invention using the corresponding seal ring is described in claim 10. Advantageous embodiments are the subject of the dependent claims.

[0006] Using a seal ring as specified, the circumferential gap between the front stator unit arranged on the front side and the rear stator unit arranged on the rear side is sealed. What is the problem here is not relevant to this seal ring first. In a particularly preferred use, this seal ring is installed in a gas turbine. Here, this seal ring has a plurality of seal components.

[0007] This seal ring defines a rotor axis, and a split surface is provided by this rotor axis. There is an upper side on one side of this split surface and a lower side on the opposite side. This seal ring can further be split into a left side and a right side perpendicular to this split surface. In this case, this seal ring can be split into four sectors in the circumferential direction, namely, the upper right, the lower right, the lower left, and the upper left.

[0008] In this case, the seal ring according to the invention requires an upper left seal component in the upper left sector, a lower right seal component in the lower right sector located on the opposite side across the rotor axis, an upper right seal component in the upper right sector, and a lower left seal component in the lower left sector. In this case, each of these seal components does not necessarily have to be completely within its respective sector. At least what is required is that these four seal components each have one seal section, one bent section, and one overlapping section.

[0009] Here, this seal section extends over most of the circumferential length of the seal component. In this case, this seal section has a seal thickness in the radial direction. In contrast, in the transverse axial direction, this seal section has a seal width that is at least five times the seal thickness. Thereby, a flat shape of this seal section is obtained.

[0010] The contact section abuts against one end of the seal section and similarly extends in the circumferential direction. In this case, the width of this contact section remains the same as the seal width and is constant. However, the thickness of the contact section is reduced with respect to the seal section and is 0.6 times or less of the seal thickness.

[0011] The bend section is arranged at the opposite end of the seal section. However, in contrast to the contact section, this bend section is arranged only on the rear side and extends axially over approximately half of the width of the seal component. In this case, the thickness of the bend section is also, similarly, 0.6 times or less of the seal thickness. In contrast to the contact section, the bend section needs to be bent against the extension of the seal section around a bending axis facing the axial direction and extend substantially in the radial direction. Here, the radial extension of the bend section should preferably be more than half of the seal width and less than or equal to the seal width. For manufacturing, it is advantageous that one free end can be bent in the radial direction.

[0012] The overlap section is arranged adjacent to the bend section on the front side. In this case, this overlap section can be made in the same way as the contact section. Therefore, the overlap section extends circumferentially at the end of the seal section, and its width is also 0.6 times or less of the seal thickness. However, due to this arrangement adjacent to the bend section, the axial width is also reduced to approximately half of the width of the seal component.

[0013] This new form, which includes a special arrangement of the contact section, an opposing bent section, and an overlapping section, enables an advantageous seal on the one hand and guarantees easy assembly on the other hand.

[0014] In this case, it is advantageous if the two contact sections of a plurality of adjacent seal components overlap each other. In this case, of course, the outer contact section must be located radially outside, and the adjacent inner contact section must be located radially inside.

[0015] Furthermore, in this case, the contact sections of the plurality of left seal components, that is, the inner contact sections on the upper or lower side of the left seal component, overlap the outer contact sections on the lower or upper side corresponding to each of the left seal components. Additionally, the contact sections of the plurality of right seal components, that is, the inner contact sections on the upper or lower side of the right seal component, overlap the outer contact sections on the lower and upper sides corresponding to each of the right seal components.

[0016] Similarly, advantageously, the two overlapping sections of a plurality of adjacent seal components are configured to overlap each other. In this case, of course, the outer overlapping section must be located radially outside, and the adjacent inner overlapping section must be located radially inside.

[0017] This embodiment of the plurality of seal components, which has a plurality of contact sections overlapping at one end and a combination of a bent section and an overlapping section at the other end, enables circumferential fixation and keeps leakage within the allowable limit. Furthermore, this embodiment is also advantageous in terms of manufacturing.

[0018] It is not initially important which contact section is arranged radially inward and which is arranged radially outward. However, considering the rotational direction of the rotor arranged inside the seal ring as specified, it is advantageous if the free end of the radially inner contact section faces the rotational direction. From this, the free end of the radially outer contact section faces the opposite direction of this rotational direction.

[0019] This also applies to the inner overlapping section and the outer overlapping section with respect to the rotational direction.

[0020] Thus, in this advantageous embodiment, the arrangement of the inner and outer contact sections at the left or right side, upper or lower part of the seal component depends on the orientation and the rotational direction.

[0021] When viewing this seal ring from the rear side to the front side in the axial direction, if the specified rotational direction is clockwise, advantageously, the seal components at the lower left side and the upper right side have inner contact sections, and conversely, the seal components at the upper left side and the lower right side have outer contact sections. In this case, the inner contact section points in the clockwise direction and the outer contact section points in the counterclockwise direction.

[0022] Regardless of the rotational direction and the arrangement of the plurality of overlapping inner and outer contact sections, it is always advantageous if the plurality of overlapping contact sections on the right side are arranged opposite to the plurality of contact sections on the left side with the rotor axis in between.

[0023] Basically, it would be possible to arrange the contact sections in the area of a dividing plane. Here, this dividing plane is defined by the rotor axis, and the plurality of adjacent stator units are divided into an upper unit and a lower unit by this dividing plane in order to enable the mounting of the rotor as specified. It should be noted that this structural division of these stator units does not necessarily have to be carried out strictly within that dividing plane; rather, these stator units may be divided along this dividing plane.

[0024] However, considering the specified dividing plane, it is particularly advantageous if these multiple contact sections are arranged on the upper side of one side of this dividing plane and on the lower side of the opposite side. When viewed in the direction of rotation, in this case, these multiple contact sections should each be arranged in front of this dividing plane. According to the above example with a clockwise direction of rotation, it is advantageous if the multiple contact sections on the left side are located below the dividing plane and the multiple contact sections on the right side are located above the dividing plane.

[0025] This advantageous arrangement of the inner and outer multiple contact sections, together with the positioning of the contact sections offset slightly with respect to the dividing plane, i.e., twisted around the rotor axis, enables the upper half of the stator unit to be particularly advantageously attached on top of the lower half of the stator unit. In this case, it becomes possible to securely attach these sealing parts to the opposite stator half in an offset state with respect to the dividing plane without the risk of damaging the sealing parts during the process of joining both stator halves.

[0026] However, basically, especially in relation to the arrangement of the contact sections in front of the dividing plane, it is particularly advantageous if the circumferential range of the inner contact sections of each sealing part is smaller than the circumferential range of the overlapping outer contact sections of the sealing part. According to this embodiment, for example, it is possible to arrange multiple contact sections outside the dividing plane and arrange all the bent sections in the same way within each sector on the opposite side.

[0027] These bent sections enable circumferential fixation of respective seal components. Considering a plurality of adjacent seal components, it is advantageous that for each bent section of one seal component, one opposing bent section of an adjacent seal component is arranged. In this way, the plurality of bent sections associated with two seal components can fix them at the same circumferential position.

[0028] At this time, it is further advantageous for leakage reduction if the free ends of the plurality of adjacent bent sections are in contact with each other. Thereby, a gap between the opposing bent sections can be avoided. For compensating circumferential thermal expansion (i.e., the relative change in the length of the seal section with respect to the dimensional change of the adjacent front or rear stator unit), it is further advantageous if these plurality of bent sections are spaced apart from each other in the attachment region to respective seal components in the initial state. It is further advantageous to provide elastic deformation of these bent sections for enabling compensation of thermal expansion.

[0029] Four seal components are sufficient for the circumferential part, but it is further advantageous if one upper main component and one lower main component are present in the seal ring as additional seal components. In this case, each of these main parts should similarly have one seal section, one bent section and one overlapping section at one end of this seal section. However, in contrast to the left and right seal components, it is further advantageous that these two main components also have one bent section and one overlapping section at the opposite end of the seal section. Regarding the embodiments of the seal section, bent section and overlapping section, the same applies as described above for the left and right seal components.

[0030] In this case, it is further advantageous if the sealing section of each main component extends over 120° or more in the circumferential direction. It is particularly advantageous if the sealing section extends over 150° or more in the circumferential direction.

[0031] The seal ring according to the present invention makes it possible to realize the stator assembly according to the present invention. In this case, the stator assembly according to this provision first has one front stator unit on the front side and one rear stator unit on the rear side. There is a gap between the front stator unit and the rear stator unit, and one seal ring is arranged in this gap. According to the present invention, this seal ring is of the embodiment according to the above description.

[0032] The embodiments of the front stator unit and the rear stator unit are not relevant first. This embodiment can be used particularly advantageously if the front stator unit comprises a plurality of stator segments arranged dispersedly in the circumferential direction. Similarly, it is advantageous if the rear stator unit comprises a plurality of stator segments arranged dispersedly in the circumferential direction.

[0033] In this case, it is even more particularly advantageous if at least four rear stator segments each have one notch, this notch is arranged on the side facing the gap, and at least one bent section is engaged in each of the notches. Nevertheless, it is also possible for other or all of the stator segments to have similar notches.

[0034] In the plurality of segmented stator segments, it can be provided such that one stator segment extends on both sides beyond the dividing surface on the left and right sides respectively. When this stator unit is divided into an upper half and a lower half, the stator segment located in the region of the dividing surface is attached to either the upper half or the lower half.

[0035] Particularly preferably, the assignment to the upper or lower half is made depending on which half the seal part with the outer contact section is attached to. In this case, the two rear stator segments in contact with the seal parts having outer contact sections on the left and right sides should be attached to the same half respectively.

[0036] In the case of the structure of the upper left seal part having an outer contact section and a clockwise rotation direction, the left rear stator segment intersecting the split surface should preferably be attached to the upper half on the left side. Similarly, in the form having the lower right seal part with an outer contact section, the right rear stator segment intersecting the split surface is attached to the lower half.

[0037] In order to advantageously couple the upper and lower halves of the split stator unit to the split seal ring, it is more advantageous if the right and left seal parts having outer contact sections and adjacent to a plurality of rear stator segments intersecting the split surface extend circumferentially beyond the split surface and further beyond the entire width of the adjacent stator segments.

[0038] In the case of an exemplary clockwise rotation direction with an upper left seal part having an outer contact section and a left rear stator segment attached to the upper half and extending on the split surface, it is advantageous if the upper left seal part extends downward beyond the split surface to the lower part of the stator segment arranged adjacent to the split surface.

[0039] Similarly, in the case of an exemplary clockwise rotation direction with a lower right seal part having an outer contact section and a right rear stator segment attached to the lower half and extending on the split surface, it is advantageous if the lower right seal part extends upward beyond the split surface to the upper part of the stator segment arranged adjacent to the split surface.

[0040] The following drawings illustrate exemplary embodiments of a seal ring according to the present invention and its arrangement in the gap between a front stator unit and a rear stator unit:

Brief Description of the Drawings

[0041]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Embodiments for Carrying Out the Invention

[0042] Figure 1 schematically shows an exemplary embodiment of the sealing ring 01 according to the present invention, and this sealing ring 01 includes six sealing components. This sealing ring 01 is shown as viewed in the axial direction, and the horizontal central part forms a dividing surface 06. In this figure, there is a left side 07 on the left side of the rotor axis 02 and a right side 08 on the right side of the rotor axis 02. In this exemplary embodiment, it is assumed that the rotation direction 03 of the rotor arranged inside the sealing ring 01 as specified is clockwise. Further, in this exemplary embodiment, Figure 1 is a view seen from the rear side 04 to the front side 05.

[0043] First, as essential components, the sealing ring 01 includes a sealing component 21 in the upper left part and a sealing component 24 in the lower right part that is positioned opposite across the rotor axis 02. These are respectively arranged adjacent to a sealing component 26 in the lower left part and a sealing component 23 in the upper right part that is positioned opposite to this.

[0044] Furthermore, this exemplary embodiment includes an upper main component 22, and this upper main component 22 extends from the sealing component 21 in the upper left part to the sealing component 23 in the upper right part. Similarly, a lower main component 25 is provided between the sealing component 24 in the lower right part and the sealing component 26 in the lower left part on the lower side.

[0045] For further description of the left and right sealing components 21, 23, 24, and 26, please refer to the subsequent Figures 2, 3, and 4. As an example, Figures 2 and 3 show the sealing component 21 in the upper left part, and this sealing component 21 in the upper left part has the same design as the sealing component 24 in the lower right part. In contrast, Figure 4 shows the sealing component 26 in the lower left part, and this sealing component 26 in the lower left part has the same design as the sealing component 23 in the upper right part located on the opposite side.

[0046] It can be seen that these sealing components 21, 23, 24, and 26 have a sealing section 31 over most of the circumferential length. This sealing section 31 has a sealing thickness in the radial direction and a sealing width in the axial direction.

[0047] One contact section 32 is arranged at each end of the seal section 31. Similarly, this 32 also extends in the circumferential direction with its seal width. Here, the contact sections 32 of the adjacent seal parts 21 and 26, and 23 and 24 are configured to overlap (see FIG. 5 in particular for this). Therefore, on one of the adjacent seal parts 21, 24 of the seal parts 21 and 26, and 23 and 24, an outer contact section 32b needs to be arranged on the radially outer side, and on the other seal parts 23, 24, an inner contact section 32a needs to be arranged on the radially inner side.

[0048] Referring to FIG. 1, it can be seen that a plurality of contact sections 32 are provided in the region of the split surface 06.

[0049] Bending sections 33 are arranged on the opposite sides of the contact sections 32 on the seal parts 21 and 26, and 23 and 24. The bending sections 33 are arranged on the rear side 04, and their width is about half of the seal width. In this case, the bending section 33 extends substantially in the radial direction with a reduced thickness, and this radial range is approximately the same as the width of the bending section 33. Please refer to FIGS. 6 and 7 in particular for this.

[0050] Furthermore, for each bending section 33 of the seal parts 21 to 26, it is configured such that there is one opposing bending section 33 of the adjacent seal parts 21 to 26 (see FIG. 8 in particular). In this case, furthermore, the free ends of these opposing bending sections 33 are in contact with each other, while on the other hand, these bending sections 33 are configured to be separated from each other in the attachment region to their respective seal sections 31.

[0051] Axially adjacent to this bent section 33, there is one overlapping section 34 at each end of the seal section 31. This has a reduced thickness similar to the contact section 32, and its width is only about half of the seal width. Similarly here, the two overlapping sections of the adjacent seal parts 21 - 26 are configured to overlap each other. Therefore, similar to the contact section 32, one inner and one outer overlapping section 34 are alternately required for the seal parts 21 - 26. Also refer to FIGS. 6 - 8 for this point.

[0052] FIG. 9 schematically shows a cross - section of a stator assembly including a rear stator unit 14 and a front stator unit 15. It can be seen that these stator units are formed from a plurality of rear stator segments 16 and a plurality of front stator segments 17. There is a circumferential gap 18 between the rear stator unit 14 and the front stator unit 15, and in this gap 18, as described above, for example, a seal ring 01 is arranged (the seal ring 01 is not shown in this figure).

[0053] At least, it is clear that these stator segments have a shape inclined with respect to the rotor axis 02. As a result, the individual stator segments 16, 17 intersect the split surface 06. Therefore, when splitting into the upper half and the lower half, it is necessary to arrange the plurality of stator segments 16, 17 existing in the region of the split surface 06 in the upper half or the lower half.

[0054] Furthermore, it is shown that each of the plurality of rear stator segments 16 has a notch 19 facing the gap 18 at the corner of the part.

[0055] In FIG. 10, the arrangement of the seal ring 01 on the rear stator unit 14 is shown for each section. Also here, the rear stator segments 16 each having a respective notch 19 can be seen.

[0056] Here, the axially trailing edge of the seal ring 01 is received in the axially open groove of the rear stator segment 16. This figure shows the assembly of the seal component 21 in the upper left and the seal component 24 in the lower right. These seal components 21, 24 include a seal section 31, a contact section 32 located at the left end, and a bent section 33 and an overlapping section 34 arranged at the right end. The multiple overlapping sections 33 facing each other are circumferentially fixed here by engaging with the notch 19.

[0057] It can be further seen from this figure that the outer contact sections 32b of the seal components 21, 24 extend circumferentially beyond the width of the rear stator segment 16. As a result, the overlapping contact sections 32 of the adjacent seal components 21, 26; 23, 24 are arranged at a distance from the dividing line between the individual stator segments 16 within the region of the stator segment 16 when viewed in the circumferential direction.

[0058] Figure 11 shows the division of the seal ring 01 and the rear stator unit 14 into upper and lower halves. This division is necessary insofar as the housing surrounding the rotor, and thus the seal ring 01 and the stator units 14, 15, must be divided for the assembly of the rotor.

[0059] In this exemplary embodiment, the seal components 21, 24 with the outer contact sections 32b are attached to the half parts, and to this half, adjacent rear stator segments 16 intersecting the dividing surface 06 in the region of the gap 08 are also attached. The bent sections 33 of the seal components 21, 24 are fixed within the notch 19 between the adjacent rear stator segments 16 along the rotational direction 03 of the dividing surface 06. In this case, the seal components 21, 24 extend beyond the rear stator segment 16 adjacent to the dividing surface 06 towards the opposite side of the rotational direction 03.

[0060] In contrast, the seal components 23 and 26, which have the inner contact section 32a and are adjacent to each other on the side opposite to the rotation direction 03 in the circumferential direction, are located in the other halves, respectively.

[0061] The lower half with the seal component 24 at the lower right is shown at the lower part of the screen in FIG. 11, and the upper half with the seal component 23 at the upper right is partially shown at the upper part of the screen. When looking at the left side with reference to this screen, the lower half of the seal ring 01 is at the upper part of the screen, and the lower half of the rear stator unit 14 is at the lower part of the screen.

Claims

1. A sealing ring (01) for sealing a gap (19) that circumscribes a rotor axis (02) between a rear stator unit (14) at the rear side (04) and a front stator unit (15) at the front side (05), comprising an upper left hand seal component (21) on the left side (07), a lower right hand seal component (24) on the right side (08) positioned opposite across the rotor axis (02), an upper right hand seal component (23), and a lower left hand seal component (26) positioned opposite across the rotor axis (02), wherein the four seal components (21, 23, 24, 26) each have a seal section (31) that extends in the circumferential direction and has a radial seal thickness and an axial seal width that is at least five times greater, a contact section (32) that is disposed at a first end of the seal section (31), extends in the circumferential direction with the seal width, and has a thickness that is 0.6 times or less the seal thickness, a bend section (33) that is disposed on the front side (05), at an end opposite the seal section (31) and disposed on the rear side (04), extends over a length that is at least 0.5 times the seal width in the radial and axial directions, and has a thickness that is 0.6 times or less the seal thickness, and an overlap section (33) that is disposed on the front side (05) adjacent to the bend section (33), extends in the circumferential direction, and has a thickness that is 0.6 times or less the seal thickness; a sealing ring having the above components.

2. A plurality of inner contact sections (32a) are disposed on the side facing the rotor axis (02), and a plurality of outer contact sections (32b) are disposed radially outward so as to overlap with one inner contact section (32a) each, and / or, a plurality of contact sections (32) of a plurality of seal components (21, 26) on the left side overlap, and a plurality of contact sections (32) of a plurality of seal components (23, 24) on the right side overlap, The sealing ring (01) according to claim 1.

3. A plurality of inner contact sections (32a) are disposed on the side facing the rotor axis (02), the free ends thereof face the rotational direction (03) of a rotor disposed inside the sealing ring as defined, and a plurality of outer contact sections (32b) are disposed radially outward so as to overlap with the respective inner contact sections (32a), Its free end faces in the direction opposite to the rotation direction (03). The sealing ring (01) according to claim 1 or 2.

4. The plurality of right-side (08) contact sections (32) are arranged opposite to the plurality of contact sections (32) on the left side (07) with the rotor axis (02) interposed therebetween. The sealing ring (01) according to claim 2 or 3.

5. In the normal mounting position, the plurality of contact sections (32) are arranged in front of the split surface (06) in the rotation direction (03). The sealing ring (01) according to claim 4.

6. The circumferential range of the inner contact section (32a) of the sealing component (23, 26) is smaller than the range of the outer contact section (32b) of the sealing component (21, 24). The sealing ring (01) according to any one of claims 2 to 5.

7. For each bending section (33) of one sealing component (21 - 26), one opposing bending section (33) of an adjacent sealing component (21 - 26) is arranged. The sealing ring (01) according to any one of claims 1 to 6.

8. The plurality of opposing bending sections (33) contact at the radially outer free end and are spaced apart from each other in the connection region with each sealing section (31). The sealing ring (01) according to claim 7.

9. Including an upper main component (22) and a lower main component (25), each of which includes one sealing section (31), two bending sections (33), and two overlapping sections (34). A sealing section (31) extending circumferentially over 120° or more, particularly 150° or more. Two bending sections (33) arranged at the rear side (04) of one end of each sealing section (31). Two overlapping sections (34) arranged at the front side (05) adjacent to each bending section (33). The sealing ring according to any one of claims 1 to 8, including the above.

10. A rear stator unit (14) at the rear side (04). A front stator unit (15) at the front side (05). The sealing ring (01) according to any one of claims 1 to 9 arranged therebetween. A stator assembly comprising the above.

11. The rear stator unit (14) includes a plurality of rear stator segments (16) that are circumferentially distributed, and / or, the front stator unit (15) includes a plurality of front stator segments (17) that are circumferentially distributed, The stator assembly according to claim 10.

12. At least four of the rear stator segments (16) each have a notch (19) on the side facing the gap (18), The plurality of bent sections (33) engage with the notch (19), The stator assembly according to claim 11.

13. A plurality of the rear stator segments (16) intersecting the split surface (06) are attached to the same half where the adjacent seal parts (21, 24) having the outer contact section (32b) are arranged, The stator assembly according to claim 11 or 12.

14. The left seal part (21) and the right seal part (24) having the outer contact section (32b) extend beyond the split surface and further beyond the circumferential width of the adjacent rear stator segment (16), The stator assembly according to claim 13.

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