EP0528138A1 - Blade shroud for axial turbine - Google Patents

Blade shroud for axial turbine Download PDF

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Publication number
EP0528138A1
EP0528138A1 EP92110494A EP92110494A EP0528138A1 EP 0528138 A1 EP0528138 A1 EP 0528138A1 EP 92110494 A EP92110494 A EP 92110494A EP 92110494 A EP92110494 A EP 92110494A EP 0528138 A1 EP0528138 A1 EP 0528138A1
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EP
European Patent Office
Prior art keywords
housing
blade
gap
cover plates
blades
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP92110494A
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German (de)
French (fr)
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EP0528138B1 (en
Inventor
Franz Kreitmeier
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ABB Asea Brown Boveri Ltd
ABB AB
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ABB Asea Brown Boveri Ltd
Asea Brown Boveri AB
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Publication of EP0528138A1 publication Critical patent/EP0528138A1/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D11/00—Preventing or minimising internal leakage of working-fluid, e.g. between stages
    • F01D11/08—Preventing or minimising internal leakage of working-fluid, e.g. between stages for sealing space between rotor blade tips and stator
    • F01D11/12—Preventing or minimising internal leakage of working-fluid, e.g. between stages for sealing space between rotor blade tips and stator using a rubstrip, e.g. erodible. deformable or resiliently-biased part
    • F01D11/127—Preventing or minimising internal leakage of working-fluid, e.g. between stages for sealing space between rotor blade tips and stator using a rubstrip, e.g. erodible. deformable or resiliently-biased part with a deformable or crushable structure, e.g. honeycomb
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D11/00—Preventing or minimising internal leakage of working-fluid, e.g. between stages
    • F01D11/08—Preventing or minimising internal leakage of working-fluid, e.g. between stages for sealing space between rotor blade tips and stator
    • F01D11/12—Preventing or minimising internal leakage of working-fluid, e.g. between stages for sealing space between rotor blade tips and stator using a rubstrip, e.g. erodible. deformable or resiliently-biased part
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/12—Blades
    • F01D5/22—Blade-to-blade connections, e.g. for damping vibrations
    • F01D5/225—Blade-to-blade connections, e.g. for damping vibrations by shrouding

Definitions

  • the invention relates to a device for sealing the gap between the rotor blades and the housing of a turbomachine which is designed with a conical contour, the rotor blades being provided with circumferential cover plates which seal against the housing with prongs to form radial gaps.
  • Such devices are known. They essentially consist of cover plates with tines running in the circumferential direction, which seal against the housing or against a honeycomb arrangement (honeycomb). They form a smooth or a stepped labyrinth with pure radial gaps. As a rule, these cover plates extend over the entire blade width.
  • a known seal is shown in FIG. 1 to be described later on the basis of the rotor blade of the second stage. With the mechanically and / or thermally highly loaded blades of the last stage, for example a gas turbine, such a solution with conventional materials is no longer possible.
  • the invention tries to avoid all these disadvantages. Furthermore, it is based on the additional task of ensuring the guidance of the main flow in the case of blades of the type mentioned at the beginning.
  • this is achieved in that the conical end of the blades seals on the inlet and outlet sides with the tip against the housing and that the cover plate arranged in the center at the blade end has three throttle points against the housing, the throttle point on the inlet side forming a diagonal gap.
  • the advantage of the invention can be seen, inter alia, in the fact that only small amounts of gap occur in the new seal, which is particularly important in the case of output stages. In this way, high efficiencies of the combination power amplifier / diffuser can be achieved. Furthermore, due to the narrow shroud, low friction losses are to be expected at the high peripheral speeds.
  • cover plates are rotationally symmetrical and if the parting lines between adjacent cover plates run in the direction of the chord. With this training, the inevitable Leakage flow deflected between the cover plates in the direction of the main flow.
  • the parting line is provided with three steps, the steps running in the axial plane of the three throttling points.
  • the blades come into contact between adjacent cover plates when the blades are unwinding. This creates the necessary damping effect.
  • the blade end advantageously has a lower inclination than the housing contour.
  • This inclination should be such that there is a positive offset at the blade end, which has its greatest value in the area of the blade leading edge and which protrudes into a gap relief chamber arranged in the housing. With this gap relief, a reduction in the leakage flow through the shroud is achieved by pushing the main flow near the gap.
  • cover plate spike which forms the middle throttle point, is in the axial plane of the blade's heavy line, additional bending moments on the blade are avoided.
  • honeycomb seals also ensure that the heat generated when touching remains as low as possible. The strength properties of the highly stressed elements involved remain intact.
  • the teeth of the cover plates which form the throttling points are preferably tapered in the circumferential direction on the cover plate overhangs.
  • the three-stage gas turbine in FIG. 1 essentially consists of the bladed rotor 1 and the blade carrier 2 equipped with guide blades.
  • the blade carrier which has a strongly conical channel contour of 40 °, is suspended in a turbine housing, not shown.
  • the term blade carrier is synonymous with the term housing.
  • the working medium enters the turbine from the outlet of the combustion chamber 3.
  • the channel through which it flows opens into the exhaust gas housing, of which only the inner walls 4 of the diffuser are shown.
  • the blading consists of three guide rows 5a, 5b and 5c and three run rows 6a, 6b and 6c.
  • the blades of the guide rows seal against the rotor 1 by means of cover strips 7.
  • the blades of the first rotor row 6a are free-standing; ie they seal with the blade tip against the blade carrier 2.
  • the blades of the middle row 6b are provided with the cover plate seal 8 known per se.
  • the actual seal consists of tines running in the circumferential direction, which run against a honeycomb arrangement (honeycomb) 9.
  • honeycomb honeycomb
  • the cover plates which extend across the entire blade width, form a stepped labyrinth with pure radial gaps. In the present case it is assumed that the rotor and the housing converge during operation due to the large relative axial expansions. For this reason, a further honeycomb arrangement 10 is provided on the blade carrier against the entry-side part of the cover plates against axial rubbing.
  • the highly loaded blades 6 of the outlet row 6c have a pitch / chord ratio of approximately 1 in the radially outer region. They work at high peripheral speeds of up to 650 m / sec in a temperature range of up to 650 ° C. According to FIG. 2, they are each provided with a cover plate 11 arranged centrally at the blade end, which forms three throttle points against the blade carrier 2. For this purpose, the plates are provided with circumferential serrations 12, 13, 14 in three different radial planes. The outlet-side prong 14 forms, together with a honeycomb arrangement 15 inserted in the blade carrier 2, a radial gap 16.
  • the entry-side prong 12 runs diagonally and, together with a correspondingly configured honeycomb arrangement 18, forms a diagonal gap 19.
  • the operating position is shown in FIG. 2, that is to say the position in which the diagonal gap 19 represents the operating play. The axial expansion is thus used to create a throttle gap.
  • the three prongs enclose two vortex chambers 20, 21, the radial displacement of the throttle points not influencing one another.
  • the conical end of the blades seals on the inlet and outlet sides with the tip 24, respectively. 29 against the housing.
  • An additional throttle point 22 is thus formed at the blade inlet via this tip seal.
  • the tip seal at the outlet also forms an additional throttling point 23 instead of the previous free swirl spaces at this point, as contained in the cover plate seal 8 in the middle row 6b. This new type of tip seal at the outlet ensures a clean flow into the diffuser.
  • the blade end is provided with a positive offset 31 on the inlet side.
  • This offset is formed in that the blade tip has a smaller value than the taper 28 of the channel contour.
  • the offset 31 projects into a gap relief chamber 25 arranged in the blade carrier 2.
  • the inner contour of the gap relief chamber is adapted to the taper of the blade tip. This results in an aerodynamic relief of the blade gap. The pressure difference across the blade gap drops and the deflection is improved. This reduces the overall gap losses.
  • Fig. 3 it can be seen that the cover plates 11 are rotationally symmetrical.
  • the parting lines 26 between adjacent cover plates run in the direction of the chord.
  • the circumferential sides of the cover plates are provided with three steps 27. These steps run in the axial plane of the three sealing teeth to ensure a continuous seal on the sealing surfaces. In addition, these stages take over the mechanical coupling of the cover plates to one another in order to achieve the damping effect.
  • the teeth 12, 13 and 14 are tapered in the circumferential direction on the two overhangs of each cover plate. These Tapering 12a, 13a and 14a contribute significantly to the weight saving of the cover plates.
  • the invention is not limited to the exemplary embodiment shown and described.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)

Abstract

Bei einer Vorrichtung zur Dichtung des Spaltes zwischen den Laufschaufeln und dem mit konischer Kontur (28) ausgebildeteten Gehäuse (2) einer Turbomaschine die Laufschaufeln (6) mit umlaufenden Deckplatten (11) versehen, welche mit Zacken (12, 13, 14) unter Bildung von Radialspalten (16, 17) gegen das Gehäuse dichten. Das konische Ende der Schaufeln (6) dichtet eintrittseitig und austrittseitig mit der Spitze (24, 29) gegen das Gehäuse (2) und die mittig am Schaufelende angeordnete Deckplatte (11) weist drei Drosselstellen gegen das Gehäuse auf, wobei die eintrittseitige Drosselstelle einen Diagonalspalt (19) begrenzt. Das Schaufelende ist gegenüber der Kanalkontur mit einem positiven Versatz (31) versehen, welcher in eine im Schaufelträger (2) angeordnete Spaltentlastungs-Kammer (25) hineinragt. <IMAGE>In a device for sealing the gap between the rotor blades and the housing (2) of a turbomachine which is designed with a conical contour (28), the rotor blades (6) are provided with circumferential cover plates (11) which are provided with teeth (12, 13, 14) seal radial gaps (16, 17) against the housing. The conical end of the blades (6) seals on the inlet and outlet sides with the tip (24, 29) against the housing (2) and the cover plate (11) arranged centrally at the blade end has three throttle points against the housing, the throttle point on the inlet side having a diagonal gap (19) limited. The blade end is provided with a positive offset (31) relative to the channel contour, which projects into a gap relief chamber (25) arranged in the blade carrier (2). <IMAGE>

Description

Technisches GebietTechnical field

Die Erfindung betrifft eine Vorrichtung zur Dichtung des Spaltes zwischen den Laufschaufeln und dem mit konischer Kontur ausgebildeteten Gehäuse einer Turbomaschine, wobei die Laufschaufeln mit umlaufenden Deckplatten versehen sind, welche mit Zacken unter Bildung von Radialspalten gegen das Gehäuse dichten.The invention relates to a device for sealing the gap between the rotor blades and the housing of a turbomachine which is designed with a conical contour, the rotor blades being provided with circumferential cover plates which seal against the housing with prongs to form radial gaps.

Stand der TechnikState of the art

Derartige Vorrichtungen sind bekannt. Sie bestehen im wesentlichen aus Deckplatten mit in Umfangsrichtung verlaufenden Zacken, die gegen das Gehäuse oder gegen eine Honigwabenanordnung (honeycomb) dichten. Dabei bilden sie ein glattes oder ein gestuftes Labyrinth mit reinen Radialspalten. In der Regel erstrecken sich diese Deckplatten über die ganze Schaufelbreite. Eine derartige bekannte Dichtung ist in der später zu beschreibenden Fig. 1 anhand der Laufschaufel der zweiten Stufe dargestellt. Bei den mechanisch und/oder thermisch hochbelasteten Laufschaufeln der letzten Stufe beispielsweise einer Gasturbine ist eine derartige Lösung mit herkömmlichen Werkstoffen nicht mehr möglich.Such devices are known. They essentially consist of cover plates with tines running in the circumferential direction, which seal against the housing or against a honeycomb arrangement (honeycomb). They form a smooth or a stepped labyrinth with pure radial gaps. As a rule, these cover plates extend over the entire blade width. Such a known seal is shown in FIG. 1 to be described later on the basis of the rotor blade of the second stage. With the mechanically and / or thermally highly loaded blades of the last stage, for example a gas turbine, such a solution with conventional materials is no longer possible.

Abhilfe schafft hier die klassische Spitzendichtung mit Dämpfervorrichtung in der Hauptströmung. Eine solche Dämpfervorrichtung, welche beispielsweise ein Dämpferdraht sein kann, ist unbedingt erforderlich bei freistehenden langen Schaufeln mit tiefer Eigenfrequenz. Schaufeln mit Spitzendichtung und Mitteln zur Schwingungsverhütung weisen indes den Nachteil von grosser Dissipation am Dämpferdraht und in der Spitzendichtung auf.This can be remedied by the classic tip seal with a damper device in the main flow. Such a damper device, which can be a damper wire, for example, is absolutely necessary for free-standing, long blades with a low natural frequency. However, blades with tip seals and means for preventing vibrations have the disadvantage of large dissipation on the damper wire and in the tip seal.

Darstellung der ErfindungPresentation of the invention

Die Erfindung versucht all diese Nachteile zu vermeiden. Desweiteren liegt ihr noch die zusätzliche Aufgabe zugrunde, bei Schaufeln der eingangs genannten Art die Führung der Hauptströmung zu gewährleisten.The invention tries to avoid all these disadvantages. Furthermore, it is based on the additional task of ensuring the guidance of the main flow in the case of blades of the type mentioned at the beginning.

Erfindungsgemäss wird dies dadurch erreicht, dass das konische Ende der Schaufeln eintrittseitig und austrittseitig mit der Spitze gegen das Gehäuse dichtet und dass die mittig am Schaufelende angeordnete Deckplatte drei Drosselstellen gegen das Gehäuse aufweist, wobei die eintrittseitige Drosselstelle einen Diagonalspalt bildet.According to the invention, this is achieved in that the conical end of the blades seals on the inlet and outlet sides with the tip against the housing and that the cover plate arranged in the center at the blade end has three throttle points against the housing, the throttle point on the inlet side forming a diagonal gap.

Der Vorteil der Erfindung ist unter anderem darin zu sehen, dass bei der neuen Dichtung nur kleine Spaltmengen auftreten, was insbesondere wichtig ist bei Endstufen. Hierdurch können hohe Wirkungsgrade der Kombination Endstufe/ Diffusor erzielt werden. Darüberhinaus sind durch das schmale Deckband bei den hohen Umfangsgeschwindigkeiten geringe Reibungsverluste zu erwarten.The advantage of the invention can be seen, inter alia, in the fact that only small amounts of gap occur in the new seal, which is particularly important in the case of output stages. In this way, high efficiencies of the combination power amplifier / diffuser can be achieved. Furthermore, due to the narrow shroud, low friction losses are to be expected at the high peripheral speeds.

Es ist besonders zweckmässig, wenn die Deckplatten rotationssymmetrisch ausgebildet sind und wenn die Trennfugen zwischen benachbarten Deckplatten in Richtung der Profilsehne verlaufen. Bei dieser Ausbildung wird die unvermeidliche Leckströmung zwischen den Deckplatten in Richtung der Hauptströmung umgelenkt.It is particularly expedient if the cover plates are rotationally symmetrical and if the parting lines between adjacent cover plates run in the direction of the chord. With this training, the inevitable Leakage flow deflected between the cover plates in the direction of the main flow.

Ferner ist es vorteilhaft, wenn die Trennfuge mit drei Stufen versehen ist, wobei die Stufen in der Axialebene der drei Drosselstellen verlaufen. Anlässlich des Betriebes der Turbomaschine kommt es in diesen Stufen zwischen benachbarten Deckpatten bei der Entwindung der Schaufeln zur Anlage. Hierdurch entsteht die erforderliche dämpfende Wirkung.It is also advantageous if the parting line is provided with three steps, the steps running in the axial plane of the three throttling points. On the occasion of the operation of the turbomachine, the blades come into contact between adjacent cover plates when the blades are unwinding. This creates the necessary damping effect.

Mit Vorteil weist das Schaufelende gegenüber der Gehäusekontur eine geringere Neigung auf. Dies Neigung soll so bemessen sein, dass ein positiver Versatz am Schaufelende entsteht, welcher seinen grössten Wert im Bereich der Schaufeleintrittskante aufweist und welcher in eine im Gehäuse angeordnete Spaltentlastungs-Kammer hineinragt. Mit dieser Spaltentlastung wird eine Reduktion des Leckagestromes über das Deckband erzielt, indem die Hauptströmung in Spaltnähe abgedrängt wird.The blade end advantageously has a lower inclination than the housing contour. This inclination should be such that there is a positive offset at the blade end, which has its greatest value in the area of the blade leading edge and which protrudes into a gap relief chamber arranged in the housing. With this gap relief, a reduction in the leakage flow through the shroud is achieved by pushing the main flow near the gap.

Sofern sich der Deckplatten-Zacken, welcher die mittlere Drosselstelle bildet, in der Axialebene der Schaufelschwerlinie befindet, werden zusätzliche Biegemomente auf das Schaufelblatt vermieden.If the cover plate spike, which forms the middle throttle point, is in the axial plane of the blade's heavy line, additional bending moments on the blade are avoided.

Ist darüberhinaus das Gehäuse an den drei Drosselstellen mit Honigwabenanordnungen versehen, so sind bei einem allfälligen Anstreifen keine Beschädigungen am hochempfindlichen Deckband zu erwarten; Diese Honigwabendichtungen bewirken auch, dass die Wärmeentwicklung beim Anstreifen möglichst gering bleibt. Damit bleiben auch die Festigkeitseigenschaften der beteiligten hochbelasteten Elemente intakt.In addition, if the housing is provided with honeycomb arrangements at the three throttling points, no damage to the highly sensitive cover tape is to be expected if it is touched; These honeycomb seals also ensure that the heat generated when touching remains as low as possible. The strength properties of the highly stressed elements involved remain intact.

Schliesslich werden zur Gewichtsreduktion der Deckplatten vorzugsweise die die Drosselstellen bildenden Zacken der Deckplatten an den Deckplattenüberhängen in Umfangsrichtung verjüngt ausgebildet.Finally, in order to reduce the weight of the cover plates, the teeth of the cover plates which form the throttling points are preferably tapered in the circumferential direction on the cover plate overhangs.

Kurze Beschreibung der ZeichnungBrief description of the drawing

In der Zeichnung ist ein Ausführungsbeispiel der Erfindung anhand einer axialdurchströmten Gasturbine dargestellt.
Es zeigen:

Fig. 1
einen Teillängsschnitt der Gasturbine;
Fig. 2
einen Teilquerschnitt durch die Dichtvorrichtung der letzten Laufreihe;
Fig. 3
die teilweise Abwicklung einer Draufsicht auf die Schaufelenden der letzten Laufreihe.
In the drawing, an embodiment of the invention is shown based on an axially flow-through gas turbine.
Show it:
Fig. 1
a partial longitudinal section of the gas turbine;
Fig. 2
a partial cross section through the sealing device of the last row of runs;
Fig. 3
the partial processing of a top view of the blade ends of the last row of runs.

Es sind nur die für das Verständnis der Erfindung wesentlichen Elemente gezeigt. Nur angedeutet sind beispielsweise die angrenzenden Anlageteile wie Brennkammer und Austrittsdiffusor sowie die Schaufelfüsse. Nicht dargestellt ist die bei dieser Art von Maschinen übliche Schaufelkühlung. Die Strömungsrichtung der Arbeitsmittel ist mit Pfeilen bezeichnet.Only the elements essential for understanding the invention are shown. The adjacent parts of the system, such as the combustion chamber and outlet diffuser, as well as the blade roots, are only indicated. The blade cooling which is customary in this type of machine is not shown. The direction of flow of the work equipment is indicated by arrows.

Weg zur Ausführung der ErfindungWay of carrying out the invention

Die dreistufige Gasturbine in Fig. 1 besteht im wesentlichen aus dem beschaufelten Rotor 1 und dem mit Leitschaufeln bestückten Schaufelträger 2. Der Schaufelträger, der eine stark konische Kanalkontur von 40° aufweist, ist in einem nichtgezeigten Turbinengehäuse eingehängt. Nachstehend ist der Begriff Schaufelträger gleichbedeutend mit dem Begriff Gehäuse. Vom Austritt der Brennkammer 3 gelangt das Arbeitsmittel in die Turbine. Deren durchströmter Kanal mündet in das Abgasgehäuse, von dem bloss die Innenwandungen 4 des Diffusors gezeigt sind. Die Beschaufelung besteht aus drei Leitreihen 5a, 5b und 5c sowie drei Laufreihen 6a, 6b und 6c. Die Schaufeln der Leitreihen dichten mittels Deckbändern 7 gegen den Rotor 1. Die Schaufeln der ersten Laufreihe 6a sind freistehend; d.h. sie dichten mit der Schaufelspitze gegen den Schaufelträger 2. Die Schaufeln der mittleren Laufreihe 6b sind mit der eingangs erwähnten, an sich bekannten Deckplattendichtung 8 versehen. Die eigentliche Dichtung besteht aus in Umfangsrichtung verlaufenden Zacken, die gegen eine Honigwabenanordnung (honeycomb) 9 laufen. Die sich über die ganze Schaufelbreite erstreckenden Deckplatten bilden dabei ein gestuftes Labyrinth mit reinen Radialspalten. Im vorliegenden Fall sei angenommen, dass während des Betriebes der Rotor und das Gehäuse anlässlich der grossen relativen Axialdehnungen aufeinander zulaufen. Deshalb ist gegen axiales Anstreifen eine weitere Honigwabenanordnung 10 am Schaufelträger gegenüber der eintrittsseitigen Partie der Deckplatten vorgesehen.The three-stage gas turbine in FIG. 1 essentially consists of the bladed rotor 1 and the blade carrier 2 equipped with guide blades. The blade carrier, which has a strongly conical channel contour of 40 °, is suspended in a turbine housing, not shown. In the following, the term blade carrier is synonymous with the term housing. The working medium enters the turbine from the outlet of the combustion chamber 3. The channel through which it flows opens into the exhaust gas housing, of which only the inner walls 4 of the diffuser are shown. The blading consists of three guide rows 5a, 5b and 5c and three run rows 6a, 6b and 6c. The blades of the guide rows seal against the rotor 1 by means of cover strips 7. The blades of the first rotor row 6a are free-standing; ie they seal with the blade tip against the blade carrier 2. The blades of the middle row 6b are provided with the cover plate seal 8 known per se. The actual seal consists of tines running in the circumferential direction, which run against a honeycomb arrangement (honeycomb) 9. The cover plates, which extend across the entire blade width, form a stepped labyrinth with pure radial gaps. In the present case it is assumed that the rotor and the housing converge during operation due to the large relative axial expansions. For this reason, a further honeycomb arrangement 10 is provided on the blade carrier against the entry-side part of the cover plates against axial rubbing.

Die hoch belasteten Laufschaufeln 6 der Austrittslaufreihe 6c weisen im radial äusseren Bereich ein Verhältnis Teilung/Sehne von ca. 1 auf. Sie arbeiten mit grossen Spitzenumfangsgeschwindigkeiten von bis zu 650 m/sec in einem Temperaturbereich von bis zu 650°C. Sie sind gemäss Fig. 2 mit je einer mittig am Schaufelende angeordneten Deckplatte 11 versehen, welche drei Drosselstellen gegen den Schaufelträger 2 bildet. Hierzu sind die Platten in drei verschiedenen Radialebenen mit umlaufenden Zacken 12, 13, 14 versehen. Der austrittseitige Zacken 14 bildet zusammen mit einer im Schaufelträger 2 eingesetzten Honigwabenanordnung 15 einen Radialspalt 16. Der mittlere Zacken 13, welcher sich in der Axialebene der Schaufelschwerlinie 30 befindet, bildet zusammen mit der gleichen, an entsprechender Stelle abgestuften Honigwabenanordnung 15 ebenfalls einen Radialspalt 17. Der eintrittseitige Zacken 12 verläuft diagonal und bildet zusammen mit einer entsprechend konfigurierten Honigwabenanordnung 18 einen Diagonalspalt 19. In Fig. 2 ist die Betriebsposition gezeigt, jene Stellung also, bei welcher der Diagonalspalt 19 das Betriebsspiel darstellt. Die Axialdehnung wird also ausgenutzt, um einen Drosselspalt zu kreieren.The highly loaded blades 6 of the outlet row 6c have a pitch / chord ratio of approximately 1 in the radially outer region. They work at high peripheral speeds of up to 650 m / sec in a temperature range of up to 650 ° C. According to FIG. 2, they are each provided with a cover plate 11 arranged centrally at the blade end, which forms three throttle points against the blade carrier 2. For this purpose, the plates are provided with circumferential serrations 12, 13, 14 in three different radial planes. The outlet-side prong 14 forms, together with a honeycomb arrangement 15 inserted in the blade carrier 2, a radial gap 16. The central prong 13, which is located in the axial plane of the blade heavy line 30, also forms a radial gap 17 together with the same honeycomb arrangement 15 which is stepped at a corresponding point. The entry-side prong 12 runs diagonally and, together with a correspondingly configured honeycomb arrangement 18, forms a diagonal gap 19. The operating position is shown in FIG. 2, that is to say the position in which the diagonal gap 19 represents the operating play. The axial expansion is thus used to create a throttle gap.

Die drei Zacken schliessen zwei Wirbelkammern 20, 21 ein, wobei durch die radiale Versetzung der Drosselstellen diese sich gegenseitig nicht beeinflussen. Das konische Ende der Schaufeln dichtet eintrittseitig und austrittseitig mit der Spitze 24 resp. 29 gegen das Gehäuse. Am Schaufeleintritt wird somit über diese Spitzendichtung eine zusätzliche Drosselstelle 22 gebildet. Die Spitzendichtung am Austritt bildet ebenfalls eine zusätzliche Drosselstelle 23 anstelle der bisherigen freien Wirbelräume an dieser Stelle, wie sie die Deckplattendichtung 8 bei der mittleren Laufreihe 6b beinhaltet. Diese neue Art der Spitzendichtung am Austritt bewirkt eine sauber geführte Abströmung in den Diffusor.The three prongs enclose two vortex chambers 20, 21, the radial displacement of the throttle points not influencing one another. The conical end of the blades seals on the inlet and outlet sides with the tip 24, respectively. 29 against the housing. An additional throttle point 22 is thus formed at the blade inlet via this tip seal. The tip seal at the outlet also forms an additional throttling point 23 instead of the previous free swirl spaces at this point, as contained in the cover plate seal 8 in the middle row 6b. This new type of tip seal at the outlet ensures a clean flow into the diffuser.

Gemäss Fig. 2 ist das Schaufelende eintrittseitig mit einem positiven Versatz 31 versehen. Dieser Versatz wird dadurch gebildet, dass die Schaufelspitze gegenüber der Konizität 28 der Kanalkontur einen kleineren Wert aufweist. Der Versatz 31 ragt in eine im Schaufelträger 2 angeordnete Spaltentlastungs-Kammer 25 hinein. Zur Bildung der dortigen Spitzendichtung ist die Innenkontur der Spaltentlastungs-Kammer an die Konizität der Schaufelspitze angepasst. Hierdurch wird eine aerodynamische Entlastung des Schaufelspaltes bewirkt. Die Druckdifferenz über dem Schaufelspalt sinkt und die Umlenkung wird verbessert. Dadurch werden insgesamt die sogenannten Spaltverluste reduziert.2, the blade end is provided with a positive offset 31 on the inlet side. This offset is formed in that the blade tip has a smaller value than the taper 28 of the channel contour. The offset 31 projects into a gap relief chamber 25 arranged in the blade carrier 2. To form the tip seal there, the inner contour of the gap relief chamber is adapted to the taper of the blade tip. This results in an aerodynamic relief of the blade gap. The pressure difference across the blade gap drops and the deflection is improved. This reduces the overall gap losses.

In Fig. 3 ist erkennbar, dass die Deckplatten 11 rotationssymmetrisch ausgebildet sind. Die Trennfugen 26 zwischen benachbarten Deckplatten verlaufen in Richtung der Profilsehne. Die in Umfangsrichtung gelegenen Seiten der Deckplatten sind mit drei Stufen 27 versehen. Diese Stufen verlaufen in der Axialebene der drei Dichtzacken, um an den Dichtflächen eine durchgehende Dichtung zu gewährleisten. Darüberhinaus übernehmen diese Stufen die mechanische Kopplung der Deckplatten untereinander zwecks Erzielung der dämpfenden Wirkung. Die Zacken 12, 13 und 14 sind an den beiden Überhängen jeder Deckplatte in Umfangsrichtung verjüngt. Diese Verjüngungen 12a, 13a und 14a tragen wesentlich zur Gewichtsersparnis der Deckplatten bei.In Fig. 3 it can be seen that the cover plates 11 are rotationally symmetrical. The parting lines 26 between adjacent cover plates run in the direction of the chord. The circumferential sides of the cover plates are provided with three steps 27. These steps run in the axial plane of the three sealing teeth to ensure a continuous seal on the sealing surfaces. In addition, these stages take over the mechanical coupling of the cover plates to one another in order to achieve the damping effect. The teeth 12, 13 and 14 are tapered in the circumferential direction on the two overhangs of each cover plate. These Tapering 12a, 13a and 14a contribute significantly to the weight saving of the cover plates.

Selbstverständlich ist die Erfindung nicht auf das gezeigte und beschriebene Ausführungsbeispiel beschränkt. In Abweichung zur in Fig. 2 gezeigten Ausbildung könnte es zweckmässig sein, die Deckplatte mitsamt der Diagonaldichtung näher zur Schaufeleintrittskante heranzuziehen, ggfs sogar bündig mit der Eintrittskante zu gestalten, sofern dies die Festigkeitserfordernisse zulassen.Of course, the invention is not limited to the exemplary embodiment shown and described. In deviation from the design shown in FIG. 2, it could be expedient to pull the cover plate together with the diagonal seal closer to the blade leading edge, possibly even to make it flush with the leading edge, provided that the strength requirements permit this.

BezugszeichenlisteReference symbol list

11
Rotorrotor
22nd
Schaufelträger, GehäuseBlade carrier, housing
33rd
BrennkammerCombustion chamber
44th
Innenwandungen des DiffusorsInner walls of the diffuser
66
LaufschaufelBlade
5a,b,c5a, b, c
LeitreiheGuiding series
6a,b,c6a, b, c
LaufreiheRunning row
77
DeckbänderShrouds
88th
DeckplattendichtungCover plate seal
99
Honigwabenanordnung radialHoneycomb arrangement radial
1010th
Honigwabenanordnung axialHoneycomb arrangement axial
1111
DeckplatteCover plate
1212
ZackenPink
12a12a
Verjüngungrejuvenation
1313
ZackenPink
13a13a
Verjüngungrejuvenation
1414
ZackenPink
14a14a
Verjüngungrejuvenation
1515
HonigwabenanordnungHoneycomb arrangement
1616
RadialspaltRadial gap
1717th
RadialspaltRadial gap
1818th
HonigwabenanordnungHoneycomb arrangement
1919th
DiagonalspaltDiagonal gap
2020th
WirbelkammerVortex chamber
2121
WirbelkammerVortex chamber
2222
DrosselstelleThrottling point
2323
DrosselstelleThrottling point
2424th
Schaufelspitze eintrittseitigBlade tip on the inlet side
2525th
Spaltentlastungs-KammerGap relief chamber
2626
TrennfugeParting line
2727
Stufestep
2828
KonizitätTaper
2929
Schaufelspitze austrittseitigBlade tip on the outlet side
3030th
SchaufelschwerlinieHeavy blade line
3131
positiver Versatz am Schaufelendepositive offset at the end of the bucket

Claims (8)

Vorrichtung zur Dichtung des Spaltes zwischen den Laufschaufeln und dem mit konischer Kontur (28) ausgebildeteten Gehäuse (2) einer Turbomaschine, wobei die Laufschaufeln (6) mit umlaufenden Deckplatten (11) versehen sind, welche mit Zacken (12, 13, 14) unter Bildung von Radialspalten (16, 17) gegen das Gehäuse dichten,
dadurch gekennzeichnet,
dass das konische Ende der Schaufeln (6) eintrittseitig und austrittseitig mit der Spitze (24, 29) gegen das Gehäuse (2) dichtet und dass die mittig am Schaufelende angeordnete Deckplatte (11) drei Drosselstellen gegen das Gehäuse aufweist, wobei die eintrittseitige Drosselstelle einen Diagonalspalt (19) bildet.Device for sealing the gap between the rotor blades and the housing (2) of a turbomachine which is designed with a conical contour (28), the rotor blades (6) being provided with circumferential cover plates (11) which have teeth (12, 13, 14) underneath Form the formation of radial gaps (16, 17) against the housing,
characterized,
that the conical end of the blades (6) seals on the inlet and outlet sides with the tip (24, 29) against the housing (2) and that the cover plate (11) arranged centrally at the blade end has three throttle points against the housing, the throttle point on the inlet side having one Diagonal gap (19) forms. Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, dass die Deckplatten (11) rotationssymmetrisch ausgebildet sind.Apparatus according to claim 1, characterized in that the cover plates (11) are rotationally symmetrical. Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, dass die Trennfugen (26) zwischen benachbarten Deckplatten (11) in Richtung der Profilsehne verlaufen.Apparatus according to claim 1, characterized in that the parting lines (26) between adjacent cover plates (11) run in the direction of the chord. Vorrichtung nach Anspruch 3, dadurch gekennzeichnet, dass die Trennfuge (11) mit drei Stufen (27) versehen ist, wobei die Stufen in der Axialebene der Zacken (12, 13, 14) verlaufen.Device according to claim 3, characterized in that the parting line (11) is provided with three steps (27), the steps running in the axial plane of the teeth (12, 13, 14). Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, dass das Schaufelende gegenüber der Gehäusekontur (28) eine geringere Neigung aufweist derart, dass der dadurch entstehende positive Versatz (31) am Schaufelende in eine im Gehäuse (2) angeordnete Spaltentlastungs-Kammer (25) hineinragt.Device according to claim 1, characterized in that the blade end has a lower inclination than the housing contour (28) such that the resulting positive offset (31) on the blade end projects into a gap relief chamber (25) arranged in the housing (2). Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, dass der Deckplatten-Zacken (13), welcher die mittlere Drosselstelle bildet, sich zumindest annähernd in der Axialebene der Schaufelschwerlinie (16) befindet.Apparatus according to claim 1, characterized in that the cover plate prong (13), which forms the central throttle point, is at least approximately in the axial plane of the blade line of gravity (16). Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, dass an den drei Drosselstellen das Gehäuse mit Honigwabenanordnungen (15, 18) versehen ist.Device according to claim 1, characterized in that the housing is provided with honeycomb arrangements (15, 18) at the three throttling points. Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, dass die die Drosselstellen bildenden Zacken (12, 13, 14) der Deckplatten (11) an den Deckplattenüberhängen in Umfangsrichtung verjüngt (12a, 13a, 14a) sind.Device according to claim 1, characterized in that the teeth (12, 13, 14) of the cover plates (11) forming the throttling points are tapered (12a, 13a, 14a) on the cover plate overhangs.
EP92110494A 1991-08-08 1992-06-22 Blade shroud for axial turbine Expired - Lifetime EP0528138B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CH2349/91 1991-08-08
CH234991 1991-08-08

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EP0528138A1 true EP0528138A1 (en) 1993-02-24
EP0528138B1 EP0528138B1 (en) 1995-05-17

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ID=4231716

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US (1) US5238364A (en)
EP (1) EP0528138B1 (en)
JP (1) JPH05195815A (en)
CA (1) CA2074326A1 (en)
DE (1) DE59202211D1 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19821365C2 (en) * 1998-05-13 2001-09-13 Man Turbomasch Ag Ghh Borsig Cooling a honeycomb seal in the part of a gas turbine charged with hot gas
WO2009138057A2 (en) * 2008-05-13 2009-11-19 Mtu Aero Engines Gmbh Shroud for rotating blades of a turbo machine, and turbo machine
WO2010020210A2 (en) * 2008-08-16 2010-02-25 Mtu Aero Engines Gmbh Rotating blade system for a row of rotating blades of a turbomachine
EP3168416A1 (en) * 2015-11-11 2017-05-17 General Electric Company Gas turbine
EP3276129A1 (en) * 2016-07-25 2018-01-31 United Technologies Corporation Rotor blade for a gas turbine engine including a contoured tip

Families Citing this family (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6231301B1 (en) 1998-12-10 2001-05-15 United Technologies Corporation Casing treatment for a fluid compressor
EP1026367A1 (en) * 1999-02-05 2000-08-09 Siemens Aktiengesellschaft Turbomachine rotor blade tip sealing
US6241471B1 (en) * 1999-08-26 2001-06-05 General Electric Co. Turbine bucket tip shroud reinforcement
US6896483B2 (en) 2001-07-02 2005-05-24 Allison Advanced Development Company Blade track assembly
RU2302534C2 (en) * 2001-12-11 2007-07-10 Альстом (Свитзерлэнд) Лтд. Gas-turbine device
US6805530B1 (en) * 2003-04-18 2004-10-19 General Electric Company Center-located cutter teeth on shrouded turbine blades
US6890150B2 (en) * 2003-08-12 2005-05-10 General Electric Company Center-located cutter teeth on shrouded turbine blades
US6913445B1 (en) * 2003-12-12 2005-07-05 General Electric Company Center located cutter teeth on shrouded turbine blades
DE102004025321A1 (en) * 2004-05-19 2005-12-08 Alstom Technology Ltd Turbomachine blade
US20070273104A1 (en) * 2006-05-26 2007-11-29 Siemens Power Generation, Inc. Abradable labyrinth tooth seal
EP1862641A1 (en) 2006-06-02 2007-12-05 Siemens Aktiengesellschaft Annular flow channel for axial flow turbomachine
US8568095B2 (en) * 2006-12-29 2013-10-29 Carrier Corporation Reduced tip clearance losses in axial flow fans
GB2445952B (en) * 2007-01-25 2011-07-20 Siemens Ag A gas turbine engine
US7901180B2 (en) * 2007-05-07 2011-03-08 United Technologies Corporation Enhanced turbine airfoil cooling
US8534993B2 (en) * 2008-02-13 2013-09-17 United Technologies Corp. Gas turbine engines and related systems involving blade outer air seals
US8608424B2 (en) * 2009-10-09 2013-12-17 General Electric Company Contoured honeycomb seal for a turbomachine
CN102472109B (en) * 2009-12-07 2015-04-01 三菱日立电力系统株式会社 Turbine and turbine rotor blade
US8821114B2 (en) 2010-06-04 2014-09-02 Siemens Energy, Inc. Gas turbine engine sealing structure
DE102011086775A1 (en) 2011-07-20 2013-01-24 Mtu Aero Engines Gmbh Method for producing an inlet lining, inlet system, turbomachine and vane
JP5464233B2 (en) * 2012-05-25 2014-04-09 株式会社Ｉｈｉ Compressor blade
EP2998517B1 (en) * 2014-09-16 2019-03-27 Ansaldo Energia Switzerland AG Sealing arrangement at the interface between a combustor and a turbine of a gas turbine and gas turbine with such a sealing arrangement
JP6571322B2 (en) * 2014-10-06 2019-09-04 時夫 大川 Air-water thermal power generation system
DE102019216646A1 (en) * 2019-10-29 2021-04-29 MTU Aero Engines AG BLADE ARRANGEMENT FOR A FLOW MACHINE
JP2021110291A (en) * 2020-01-10 2021-08-02 三菱重工業株式会社 Rotor blade and axial flow rotary machine

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB191210179A (en) * 1911-05-04 1912-06-20 Heinrich Holzer Arrangement for Diminishing Clearance Losses in Turbines and Pumps for Liquids and Elastic Fluids.
FR1454748A (en) * 1964-11-24 1966-10-07 Bbc Brown Boveri & Cie Aerodynamic rotary machine
FR2406074A1 (en) * 1977-10-11 1979-05-11 Snecma SAFETY DEVICE FOR AXIAL ROTATING MACHINE
GB2153919A (en) * 1984-02-06 1985-08-29 Gen Electric Compressor casing recess
EP0194957A2 (en) * 1985-03-11 1986-09-17 United Technologies Corporation Compressor blade tip seal
GB2215407A (en) * 1988-03-05 1989-09-20 Rolls Royce Plc A bladed rotor assembly

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE485833C (en) * 1929-11-08 J A Maffei A G Process for the production of blades for turbo machines, in particular for steam or gas turbines
GB804922A (en) * 1956-01-13 1958-11-26 Rolls Royce Improvements in or relating to axial-flow fluid machines for example compressors andturbines
FR1403799A (en) * 1964-05-13 1965-06-25 Rateau Soc Turbine wheel subjected to partial injection
US3677660A (en) * 1969-04-08 1972-07-18 Mitsubishi Heavy Ind Ltd Propeller with kort nozzle
GB1423833A (en) * 1972-04-20 1976-02-04 Rolls Royce Rotor blades for fluid flow machines
US4370094A (en) * 1974-03-21 1983-01-25 Maschinenfabrik Augsburg-Nurnberg Aktiengesellschaft Method of and device for avoiding rotor instability to enhance dynamic power limit of turbines and compressors
DE2745130C2 (en) * 1977-10-07 1980-01-03 Mtu Motoren- Und Turbinen-Union Muenchen Gmbh, 8000 Muenchen Sealing device for the free blade ends of axial turbines
FR2452601A1 (en) * 1979-03-30 1980-10-24 Snecma REMOVABLE SEALING COVER FOR TURBOJET BLOWER HOUSING
US4576551A (en) * 1982-06-17 1986-03-18 The Garrett Corporation Turbo machine blading
FR2552159B1 (en) * 1983-09-21 1987-07-10 Snecma DEVICE FOR CONNECTING AND SEALING TURBINE STATOR BLADE SECTIONS
JPS6123804A (en) * 1984-07-10 1986-02-01 Hitachi Ltd Turbine stage structure
US4710102A (en) * 1984-11-05 1987-12-01 Ortolano Ralph J Connected turbine shrouding

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB191210179A (en) * 1911-05-04 1912-06-20 Heinrich Holzer Arrangement for Diminishing Clearance Losses in Turbines and Pumps for Liquids and Elastic Fluids.
FR1454748A (en) * 1964-11-24 1966-10-07 Bbc Brown Boveri & Cie Aerodynamic rotary machine
FR2406074A1 (en) * 1977-10-11 1979-05-11 Snecma SAFETY DEVICE FOR AXIAL ROTATING MACHINE
GB2153919A (en) * 1984-02-06 1985-08-29 Gen Electric Compressor casing recess
EP0194957A2 (en) * 1985-03-11 1986-09-17 United Technologies Corporation Compressor blade tip seal
GB2215407A (en) * 1988-03-05 1989-09-20 Rolls Royce Plc A bladed rotor assembly

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19821365C2 (en) * 1998-05-13 2001-09-13 Man Turbomasch Ag Ghh Borsig Cooling a honeycomb seal in the part of a gas turbine charged with hot gas
WO2009138057A2 (en) * 2008-05-13 2009-11-19 Mtu Aero Engines Gmbh Shroud for rotating blades of a turbo machine, and turbo machine
WO2009138057A3 (en) * 2008-05-13 2010-08-26 Mtu Aero Engines Gmbh Shroud for rotating blades of a turbo machine
WO2010020210A2 (en) * 2008-08-16 2010-02-25 Mtu Aero Engines Gmbh Rotating blade system for a row of rotating blades of a turbomachine
WO2010020210A3 (en) * 2008-08-16 2010-11-18 Mtu Aero Engines Gmbh Rotating blade system for a row of rotating blades of a turbomachine
US8684659B2 (en) 2008-08-16 2014-04-01 MTU Aero Engines AG Rotating blade system for a row of rotating blades of a turbomachine
EP3168416A1 (en) * 2015-11-11 2017-05-17 General Electric Company Gas turbine
EP3276129A1 (en) * 2016-07-25 2018-01-31 United Technologies Corporation Rotor blade for a gas turbine engine including a contoured tip
US10808539B2 (en) 2016-07-25 2020-10-20 Raytheon Technologies Corporation Rotor blade for a gas turbine engine

Also Published As

Publication number Publication date
EP0528138B1 (en) 1995-05-17
DE59202211D1 (en) 1995-06-22
US5238364A (en) 1993-08-24
JPH05195815A (en) 1993-08-03
CA2074326A1 (en) 1993-02-09

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