EP2466074A1 - Gas turbine engine with piston ring sealing device - Google Patents

Abstract

The gas turbine engine has a turbine (18) having a gas channel (20), where a sealing device (30) is provided with one piston ring element (32) for sealing the gas channel. One piston ring element is arranged between a housing (12) of the turbine and an annular segmented shroud (16) with cladding segments (15), where each cladding segments of the shroud have a receptacle (36).

Description

The present invention relates to an engine with a sealing device, in particular an aircraft engine. The sealing device in the engine is required for sealing a gas channel, for example, formed from lining segments towards the case. In this case, trim segments are provided which form part of an inner ring of the gas channel and trim segments forming part of an outer ring of the gas channel, and trim segments, the struts between the inner and outer ring dress and disposed between the lining segments of the inner and outer ring. The lining segments which form the inner or outer ring of the gas channel are so-called inner and outer panels or so-called inner and outer lining panels. Furthermore, the cladding segments which form the cladding of the struts are referred to as so-called fairing.

From the state of the art, as in the DE 29 43 464 is disclosed, a sealing device for a gas turbine engine is known. The sealing device thereby prevents a high temperature main gas flow from impinging directly on a vane / rotor disk interface during periods of maximum engine output power operation. For this purpose, the sealing device consists of a segmented, annular sealing part, which has an L-shaped cross-section. The seal member is attached to a stator assembly or a nozzle support device. The sealing member also has a honeycomb-shaped part which is fixed to the radially inner side of its axially aligned leg.

Furthermore, from the DE 602 20 636 T2 a gas turbine with opposing low pressure rotors known. In this case, a seal is provided by counter-rotating low-pressure rotors with respect to a booster and an LPT housing, through the use of brush seals. A first brush seal is disposed in a sealing arrangement between a second fan and a fan frame. Further, a second brush seal is disposed between a front end of a low pressure turbine housing and an outer drum rotor. A third brush means is between a rear end of the low-pressure turbine housing and a last stage of a low-pressure turbine blade row, with screwed to the outer drum rotor is arranged. An alternative to the brush seals are non-contact seals such as suction seals or mechanical seals. Moreover, from the EP 1270 875 A2 a gas turbine engine with a leaf spring gasket known. In this case, a leaf seal and leaf springs of the leaf spring seal between suspension of an outer segmented band and rear rails are arranged, which are connected to turbine lining segments. The leaf seal and the leaf springs are secured by mounting pins in corresponding receptacles of the suspensions.

Against this background, the invention is based on the object of designing an engine with an improved sealing device.

According to the invention, an engine, in particular an aircraft engine, is provided with a turbine with a gas channel, wherein a sealing device is provided with at least one piston ring element for sealing the gas channel.

This has the advantage that larger axial displacements can be compensated by the at least one piston ring element, which can occur during operation on the turbine or the turbine housing than is the case with leaf spring seals. Furthermore, in addition to the axial displacements, the piston ring element can also compensate for radial movements to a certain extent. As a result, the gas channel, in particular a hot gas duct, can be effectively sealed in the engine.

Advantageous embodiments and modifications of the invention will become apparent from the dependent claims and the description with reference to the drawings.

In one embodiment of the invention, at least one piston ring member is disposed between a turbine housing of the turbine and an annular segmented fairing with fairing segments. The piston ring element can in this case in addition to the displacements and radial tolerances, for example, due to the segmented formed fairing compensate.

According to a further embodiment of the invention, the lining segments of the lining each have a receptacle in which the at least one piston ring element is received and wherein the at least one piston ring member is biased radially and / or axially sealingly against a sealing surface of the turbine housing. In this way, a radial as well as an axial seal can be provided by the piston ring member.

In a further embodiment of the invention, the receptacle of the respective trim segment has an outer diameter smaller than the inner diameter of the at least one piston ring element in the receptacle to provide a radial gap between the receptacle of the trim segment and the piston ring element. The radial gap is dimensioned, for example, so that it can compensate in particular radial games of the panel and its fairing segments, special in different operating conditions of the engine.

In another embodiment of the invention, the width of the receptacle of the respective trim segment is greater than the width of the at least one piston ring element in the receptacle to provide an axial gap between the receptacle and the piston ring element. The axial gap is, for example, dimensioned such that it can in particular compensate for the axial tolerances of the lining segments (in particular if the lining segments expand differently axially during operation of the engine due to hot gas in the hot gas channel, for example).

In a further embodiment according to the invention, at least two piston ring elements are provided as sealing means. In this case, a piston ring element against a radial inner surface, e.g. the radially inner surface of the turbine housing, and the other piston ring member against a radially outer surface, e.g. the lining or the recording of the respective panel segment, be formed biased and sealing or radial sealing.

According to another embodiment of the invention at least one piston ring member is additionally provided axially sealing against the turbine housing or its ring member and / or the respective trim segment of the panel or its inclusion. In addition to the radial sealing, an axial sealing of the hot gas channel can additionally be provided in this way, if, for example, two piston ring elements are used as the sealing device,

• Fig. 1 einen Ausschnitt aus einem Flugzeugtriebwerk, wobei ein Turbinengehäuse bzw. ein Turbinenzwischengehäuse (TCF) mit einer segmentierten Verkleidung und einer Dichtungseinrichtung gezeigt ist;
• Fig. 2 einen Ausschnitt aus einem Flugzeugtriebwerk, wobei ein Turbinengehäuse bzw. ein Turbinenzwischengehäuse (TCF) mit einer segmentierten Verkleidung und einer Dichtungseinrichtung gemäß einer ersten Ausführungsform der Erfindung gezeigt sind; und
• Fig. 3 einen Ausschnitt aus einem Flugzeugtriebwerk, wobei ein Turbinengehäuse bzw. ein Turbinenzwischengehäuse (TCF) mit einer segmentierten Verkleidung und einer Dichtungseinrichtung gemäß einer zweiten Ausführungsform der Erfindung gezeigt sind.

The invention will be explained in more detail with reference to the exemplary embodiments indicated in the schematic figures of the drawings. Show it:

• Fig. 1 a portion of an aircraft engine, wherein a turbine housing or a turbine intermediate housing (TCF) is shown with a segmented panel and a sealing device;
• Fig. 2 a section of an aircraft engine, wherein a turbine housing or a turbine intermediate housing (TCF) with a segmented panel and a sealing device according to a first embodiment of the invention are shown; and
• Fig. 3 a section of an aircraft engine, wherein a turbine housing or a turbine intermediate housing (TCF) with a segmented panel and a sealing device according to a second embodiment of the invention are shown.

In the figures, like elements or similar elements are designated by like reference numerals unless otherwise indicated. The representation of the piston ring elements in the embodiments in the following Fig. 2 and 3 is not to scale.

In Fig. 1 a section of an aircraft engine 10 is shown. More specifically, in Fig. 1 Among other things, a housing 12 or that of a turbine intermediate housing (TCF) with a ring element 13 with a flange portion 14, and an annular segmented fairing 16 are shown.

As in Fig. 1 is shown, sealing of a hot gas channel 20 (TCF Flow Path) between the annular segmented panel 16 and the housing or the turbine intermediate housing (TCF) 12 via individual sealing strip segments 22, which are pressed by spring elements 24 to the sealing surface of the ring member 13 , In Fig. 1 a spring element 24 is shown which is attached to the panel 16 or an extension of the panel 16 respectively by a fastening pin 26 and a sealing strip segment 22 presses against the sealing surface of the ring member 13.

The high operating temperature prevailing in the hot gas duct 20, together with the large axial displacements that may occur, results in a loss of the spring bias of the spring elements 24 so that they can no longer sufficiently press the sealing strip segments 22 against the corresponding sealing surfaces of the ring element 13 , Due to the associated reduced sealing effect, this effect also increases. The result is that it comes to a hot gas. In addition, creeping of, for example, the turbine housing 12 and the ring element 13 may occur due to the hot gas intrusion. Furthermore, cracks in the lining 16, as well as a retaining ring (English Vane STG 1 Retainer) for a guide vane 1 of a turbine, here low-pressure turbine (not shown) may occur. The loss of the spring tension of the spring elements 24 also leads to loose vibrating sealing segments 22 and leaf springs, which thereby wear very strong, so that they can be solved and lost.

In Fig. 2 Now also a section of an aircraft engine 10 is shown. More specifically, in Fig. 2 In this case, a section of a housing 12 of a turbine intermediate housing (TCF) with a ring element 13 is shown (designed as a retaining ring of a guide blade), which has a flange portion 14. Furthermore, a vane device 17 of a turbine 18, here for example a vane device 17 with a vane stage 1 (Vane STG 1) 19 of a low-pressure turbine 18, and an annular, segmented casing 16 are shown. The segmented shroud 16 having the sealing means of the present invention has shroud segments 15 forming part of the outer ring of the gas channel 20 and shroud segments 25 covering the struts between an inner ring and the outer ring and between shroud segments 15 of the outer ring are arranged to form the outer ring of the gas channel 20. The cladding segments 15 which form part of the outer ring of the gas channel 20 are so-called outer panels or so-called outer cladding panels. The lining segments 25, which form the lining of the struts, are referred to as so-called fairing as described above. The inner ring of the gas channel 20 also has a segmented lining, with inner panels and the trim segments 25 therebetween.

In order to prevent a hot gas intrusion into the area between the hot gas duct 20 and the housing, as in the in Fig. 1 can occur structure shown, now the sealing segments including the spring elements and their mounting pins are replaced by a sealing device 30 with at least one piston ring member 32. This seal construction has the Advantage, especially with respect to Fig. 1 previously described sealing construction, that this sealing construction can compensate for larger axial displacements and, to the extent necessary, the occurring radial movements and thus permanently seals. The ability of greater compensation of axial displacement is particularly suitable for the application example shown, since axial displacements occur or may occur mainly due to high operating temperatures. Radial displacements occur to a much lesser extent since there is a segmented hot gas channel.

How out Fig. 2 can be taken, in the shown section, a part of the housing 12 of the turbine intermediate housing (TCF) is shown. In this case, the housing 12 is connected to the separately formed ring element 13, which is integrally formed, that is not formed segmented, and the flange portion 14 has. The flange portion 14 may have a sealing portion 34 for the sealing device 30 as a receptacle. The sealing portion 34 has, for example, a cylindrical sealing surface for sealingly receiving the piston ring member 32.

Further, for example, each of the trim segments 15, 25 of the outer ring trim 16 of the hot gas duct 20, i. the outer ring panels (so-called outer panels or outer cladding panels) and the fairing fairing segments 25 interposed therebetween have a receptacle 36 for the sealing means 30. In the first embodiment, the sealing device 30 has a piston ring element 32, which is received in the respective receptacle 36 of the segments 15, 25 of the panel 16.

The receptacle 36 in the respective trim segment 15 and 25 is designed such that the outer diameter of the receptacle 36 is formed smaller than the inner diameter of the piston ring member 32, so that a gap 21 results in the radial direction between the piston ring member 32 and the receptacle 36th The radial gap 21 serves in this case, for example, to provide a radial play of the lining segments 15 and 25. This play is necessary in order to enable or permit radial thermal expansions and also radial component deviations (tolerances).

Furthermore, the receptacle 36 is formed in the respective trim segment 15 and 25 such that its width is greater than the width of the piston ring element 32, so that a gap 23 in the axial direction between the receptacle 36 and the piston ring member 32 is given. The axial gap 23 serves, for example, to provide an axial play of the lining segments 15 and 25, which are assembled into a ring and the annular segmented panel 16 form to allow axial tolerances and not to impede different thermal expansion from segment to segment.

As in Fig. 2 is shown, the piston ring member 32 is received as a sealing means 30 in the seal receptacle 36 of the respective panel segment 15 and 25 of the panel 16 and sealingly abuts the associated sealing portion 34 of the ring member 13 of the housing 12 of the turbine intermediate housing (TCF). The ring member 13 and the housing 12 may also be formed so that the piston ring member 32 bears against this axially sealing. Conversely, the panel segments 15 and 25 of the panel 16 can also be formed so that the piston ring member 32 bears against these radially sealing. The axial guidance of the piston ring element 32 in this case takes place via a seal receiver 36 in the housing or the ring element. This also applies to the following second embodiment of the invention.

In Fig. 3 Furthermore, a section of an aircraft engine 10 is shown, comparable to that in FIG Fig. 2 shown section. At the in Fig. 3 shown embodiment, the sealing device 30, however, in contrast to the embodiment according to the invention in Fig. 2 a plurality of piston ring elements 32, for example, a first and second piston ring element 32nd

As before Fig. 2 also shows Fig. 3 a section of a housing 12 of a turbine intermediate housing (TCF), however, the ring member 13 is, for example, integrally formed with the turbine housing 12 and not as in Fig. 2 provided as a separate part and attached to the housing 12, for example by means of screws.

Further shows Fig. 3 as before Fig. 2 , an annular, segmented formed panel 16 with lining segments 15, which form the outer ring or a part of the outer ring (so-called outer panels) and lining segments 25, which dress the struts (so-called fairing), and a vane means 17 of a turbine 18, here eg a low-pressure turbine. The cladding fairing segments 25 and the outer ring cladding segments 15 together form the outer ring of the hot gas passage 20. In this case, the cladding segments 25 are arranged between cladding segments 15.

The lining segments 15, 25 each have a receptacle 36 for the two piston ring elements 32 of the sealing device 30. The first piston ring member 32 is sealingly on the housing 12 or its example, with the housing 12 integrally formed ring member 13 (sealing surface 34). The second piston ring element 32 in turn is sealingly against the respective trim segment 15 and 25. As in Fig. 3 is shown, the second piston ring member 32 is sealingly attached to an associated sealing surface of the receptacle 36 of the respective panel segment 15, 25.

The receptacle 36 in the respective trim segment 15, 25 is for example designed such that the outer diameter of the receptacle 36 is formed smaller than the inner diameter of the first piston ring member 32, so that a gap 21 results in the radial direction between the first piston ring member 32 and the Recording 36. The radial gap 21 serves, for example, for providing a radial play for the lining segments 15, 25. The first piston ring element lies in the radial direction in a sealing manner against the ring element 13 or the housing 12.

Furthermore, the outer diameter of the receptacle 36, for example, equal to the inner diameter of the second piston ring member 32 or forms with this a transition fit, so that the second piston ring member 32 sealingly bears against the receptacle 36 or an associated sealing surface of the receptacle 36.

Further, the receptacle 36 in the respective trim segment 15, 25 is formed so that its width is greater than the width of the two piston ring elements 32 together, so that a gap 23 is given in the axial direction between the receptacle 36 and the two piston ring elements 32. The axial gap 23 serves, for example, to provide an axial clearance for the lining segments 15, 25, which, as described above, are assembled into a ring or outer ring and form the annular segmented lining 16 for the outer ring.

The two piston ring elements 32 can now compensate for deviations in the radial direction. This means that if, for example, the lining segments 15, 25 in the radial direction move outward or expand in the radial direction, this radial expansion can be compensated by the two piston ring members 32 and the radial column 21 of the piston ring members 32. In this case, the first piston ring member 32 is sealingly on its outer periphery to the ring member 13 of the housing 12 and the second piston ring member 32 with its inner periphery sealingly against the receptacle 36 at. The same applies if the lining segments 15, 25 move in the radial direction inwards or contract in the radial direction. Again, the first piston ring member 32 lies with its outer periphery sealingly against the ring member 13 of the housing 12 and the second piston ring member 32 is sealingly against the receptacle 36 with its inner periphery.

Furthermore lies in the in Fig. 3 shown example, the first piston ring member 32 in the axial direction also sealingly on the receptacle 36 at. Due to the axial play of the receptacle 36 is the second piston ring member 32, as in Fig. 2 For example, it is not shown sealingly on the receptacle 36. In this way, for example, an expansion of the lining 16 and its lining segments 15, 25 are compensated or compensated in the axial direction and at the same time an axial seal between the panels 15, 25 and the housing 12 and its ring member 13 are provided.

In other words, the piston ring pair 32 in Fig. 3 be designed so that a piston ring member 32 (here the second Kolberingelement 32) against the radial inner surface, here the seal holder 36 in Fig. 3 , spans and seals. The other piston ring element 32 (here the first piston ring element 32) can in turn be designed such that it presses against the radial outer surface and thus seals, here the sealing section 34 of the flange section 14 of the ring element 13 Fig. 3 which as a separate part or in one piece, as in Fig. 3 , may be formed with the housing 12.

Depending on the choice of material, in the case of a more or less occurring inlet operation, tolerance-related steps between the lining 16 or its lining segments 15, 25 and the piston ring elements 32 can be reproduced and thus lead to a further improvement of the sealing effect. By the associated improvements of the contact pattern then the wear (running-in process) is further reduced.

The piston ring members 32 may either seal against the axially elongated liner 16, as in FIG Fig. 3 is shown, or against the housing 12 and against the Ring element 13 dense to the interface to the turbine, eg here low pressure turbine (LPT) 18, not to influence and also to simplify the assembly.

By means of the sealing device 30 according to the invention, a reliable hot runner sealing between the turbine housing or turbine intermediate housing (TCF) and the turbine, here e.g. Low pressure turbine (LPT) can be provided.

A piston ring pair 32, as exemplified in Fig. 3 can be designed so that a ring 32 clamps and seals against a radially inner surface, the other presses against a radial Au-βenfläche 32 and thus seals. This is useful because the inner surface to be sealed, ie the surface of the panels 15, 25, is segmented here and thus, in contrast to normal applications of piston rings or piston ring elements 32, especially in the axial direction tolerances.

These previously with reference to the embodiments in the Fig. 2 and 3 described seal construction is particularly suitable to endure the axial displacement occurring without loss of sealing effect. A hot gas collapse, for example, in areas can be avoided, which do not permanently withstand the hot gas temperatures, inevitably. This leads to a significant reduction in maintenance or maintenance costs.

The maintenance costs are significantly reduced in particular by the fact that the piston ring element solution, for example in the examples in the Fig. 2 and 3 the life of the sealing segments in Fig. 1 significantly better. In addition, consequential damage, such as cracks in the vane device 17, retaining ring element 13 and a repair of the housing of the turbine intermediate housing (TCF), for example by means of spraying or even a replacement (Replacement) can be avoided.

Although the present invention has been described above with reference to the preferred embodiments, it is not limited thereto, but modified in many ways. In particular, the embodiments described above can be combined with one another, in particular individual features thereof.

LIST OF REFERENCE NUMBERS

10

Section of aircraft engine (sub-section of a turbine intermediate housing (TCF))

12

Housing of Turbine Intermediate Housing (TCF)

13

Ring element (retaining ring for vane 1 of the LPT Vane Stg 1 Retainer)

14

Flange section (ring element)

15

Cladding segment (to form the inner and outer rings of the gas channel (inner and outer panels)

16

paneling

17

Leitschaufeleinrichtung

18

Low-pressure turbine

19

vane

20

Hot gas duct

21

radial gap

22

Sealing strip (segment)

23

axial gap

24

spring element

25

Fairing segment (fairing fairing) of the TCF)

26

fixing spin

30

seal means

32

Piston ring element

34

sealing section

36

seal Housing

Claims (12)

An engine (10), in particular an aircraft engine, with a turbine (18) with a gas channel (20), wherein a sealing device (30) with at least one piston ring element (32) for sealing the gas channel (20) is provided. Engine according to Claim 1, characterized in that the at least one piston ring element (32) is arranged between a housing (12, 13) of the turbine (18) and an annular segmented lining (16) with lining segments (15, 25). Engine according to claim 2, characterized in that the lining segments (15, 25) of the lining (16) each have a receptacle (36) in which the at least one piston ring member (32) is received and wherein the at least one piston ring member (32) radially and / or axially biased against a sealing surface of the housing (12, 13) is biased. An engine according to claim 3, characterized in that the receptacle (36) of the respective trim segment (15, 25) has an outside diameter smaller than the inside diameter of the at least one piston ring element (32) to provide a radial gap (21) between the receptacle (36) of the trim segment (15, 25) and the piston ring element (32). An engine according to claim 3 or 4, characterized in that the width of the receptacle (36) of the respective trim segment (15, 25) is greater than the width of the at least one piston ring member (32) to provide an axial gap (23) between the receptacle (36) of the respective trim segment (15, 25) and the piston ring member (32). Engine according to at least one of the preceding claims, characterized in that at least two piston ring elements (32) are provided as sealing means (30). Engine according to claim 6, characterized in that the piston ring elements (32) are designed such that a piston ring element (32) against a radial inner surface and the other piston ring member (32) is biased against a radially outer surface and sealingly formed. Engine according to one of claims 2 to 7, characterized in that a piston ring member (32) against the radial inner surface of the housing (12, 13) is provided radially sealing and the other piston ring member (32) against a radial outer surface of the respective trim segment (15, 25) and the lining (16) is formed radially sealing. Engine according to at least one of the preceding claims, characterized in that a piston ring member (32) is additionally provided axially sealing against the turbine housing (12, 13) and / or the respective trim segment (15, 25) of the panel (16). Engine according to at least one of the preceding claims, characterized in that the housing (12) has a ring element (13), wherein a piston ring element (32) is provided radially and / or axially sealingly on the ring element (13) and wherein the ring element (13 ) is formed integrally with the housing (12) or is attached as a separate part to the housing (12). Engine according to at least one of the preceding claims, characterized in that the turbine (18) is designed as a low-pressure turbine. Engine according to at least one of the preceding claims, characterized in that the gas duct (20) is a hot gas duct (20).

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