EP0362756A1 - Device for reducing stresses and deflections in turbine diaphragms - Google Patents

Device for reducing stresses and deflections in turbine diaphragms Download PDF

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Publication number
EP0362756A1
EP0362756A1 EP89118211A EP89118211A EP0362756A1 EP 0362756 A1 EP0362756 A1 EP 0362756A1 EP 89118211 A EP89118211 A EP 89118211A EP 89118211 A EP89118211 A EP 89118211A EP 0362756 A1 EP0362756 A1 EP 0362756A1
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EP
European Patent Office
Prior art keywords
diaphragm
space
turbine
pressure
outer ring
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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
EP89118211A
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German (de)
French (fr)
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EP0362756B1 (en
Inventor
Gérard Foucher
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Alstom Holdings SA
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GEC Alsthom SA
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Priority to AT89118211T priority Critical patent/ATE78320T1/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
    • F01D3/00—Machines or engines with axial-thrust balancing effected by working-fluid
    • 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
    • F01D25/00—Component parts, details, or accessories, not provided for in, or of interest apart from, other groups
    • F01D25/24—Casings; Casing parts, e.g. diaphragms, casing fastenings
    • F01D25/246—Fastening of diaphragms or stator-rings

Definitions

  • the diaphragm ( Figure 1) ensures the expansion of the fluid, either total (action turbine) or partial (reaction turbine) before it crosses the finned wheel in which the energy transfer takes place. towards the rotor.
  • the diaphragm is a capital element by the functions it performs: - Relax the fluid through the guide vanes with the best efficiency. - Support the sealing devices: . at the top of the finned wheels, . to the rotor hub - Keep the guide vanes in radial relative position in all operating cases with respect to the wheel fins. - Support the pressure difference between the upstream and downstream faces without introducing significant constraints and deflections into the mechanical elements.
  • a diaphragm is made up: ( Figure 1) - Either distributor vanes ensuring both the guiding and the expansion of the fluid passing through and the connection of its outer hoop with its center. - Either: a distribution grid ensuring the guiding and expansion function of the fluid passing through it, associated with arms (or bridges) placed upstream which provide the connection between the center and the hoop of the diaphragm.
  • the cut of the diaphragm is a source of high stresses in the bridges and the blades located in the vicinity thereof. Likewise, the arrows are higher near the plane of the cut than in the plane of symmetry perpendicular to it.
  • the inventor had the idea of modifying the distribution of the forces on the upstream face of the outer crown of the diaphragm.
  • the invention enabling this object to be achieved is characterized in that: .
  • the sealing means, between the diaphragm and the stator receiving it, are arranged on the edge of the outer ring. .
  • the downstream face of said outer ring is provided with a support remote from the edge and coming to bear on the crown of the stator. .
  • Means are provided for ensuring communication of the space between support and sealing means with a space downstream of the diaphragm, said space being at a pressure below the pressure P1 established on the upstream face of the diaphragm. .
  • This space is at the pressure P2 downstream of the stage (P2 ⁇ P1) so that there are developed forces applied to the crown at points farther from the axis of the diaphragm than the support. .
  • Reducing the stress in the connection means between the center and the diaphragm hoop makes it possible to reduce the arrows in the central part of the inner ring, which decreases the axial clearances and increases the efficiency of the stage
  • the communication means consist of slots provided in the support thus putting the space between support and the sealing means at the pressure P2 downstream of the stage comprising the diaphragm.
  • the communication means are constituted by openings provided in the stator ring on which the support bears, thus putting the space between the support and the pressure sealing means P2 downstream of the mobile stage following the stage with the diaphragm.
  • the space between the support and the sealing means are connected by pipes to one of the stages further downstream of the machine which is naturally at a pressure P lower than the pressure P2.
  • the outer ring of the diaphragm comprises a portion of larger diameter on the edge of which the sealing means are arranged.
  • the force applied to the upstream part of the crown is greater.
  • the part of larger diameter can be received between the stator fixing bolts.
  • the space located upstream of the sealing means of the edge of the outer ring of the diaphragm of one of the preceding stages is located upstream of the sealing means of the edge of the outer ring of the diaphragm of one of the preceding stages.
  • a sealing device 17 which is applied to the internal wall of the stator to seal.
  • this outer ring 3 On the downstream face 14 of this outer ring 3 is disposed a circular support 18 which comes to bear against a ring 19 of the stator 4 located around the wheel 2 and sealing devices 13.
  • This support 18 is located as close as possible to the device 13
  • the support is provided with slots 22 (see FIG. 2).
  • the diaphragm 1 is provided on its periphery with two notches 23 near the joint plane and a notch 24 at the bottom.
  • the notches 23 receive, as is conventional, keys which suspend the diaphragm 1 in the stator 4.
  • the notch 24 also receives, in a conventional manner, a key completing the guiding and ensuring with the keys of the notches 23, the assembly with free expansion.
  • the space 25 located between the sealing means 17 and the support 18 is placed by the slots 22 in communication with the pressure P2 prevailing downstream of the wheel 2.
  • the support 18 no longer has slots as in the embodiment of FIG. 1 but seals with the crown 19 of the stator 4.
  • This ring 19 is provided with transverse openings which place the space 25 between the sealing means 17 and the support 18 in communication with the downstream of the stage 20 at the pressure P2.
  • the support 18 also seals with the crown 19 and the space 25 between the sealing means 17 and the support 18 is placed in communication by a pipe 27 ′ with one of the following stages 20 ′ where a pressure P naturally prevails lower than the pressure P2 established at the outlet of stage 20.
  • FIG 6 there is shown a third variant in which the outer ring 3 has a portion of larger diameter 28 on the edge 29 of which are arranged the sealing means 17. This portion of larger diameter has a thickness such that it can be housed between the bolts 32 used for bolting the stator 4.
  • the space 25 between the support 18 and the sealing means 17 is placed in communication with the space immediately downstream of the stage 20 by slots provided in the support 18.
  • the openings 27 shown could also be used in FIG. 4 for this connection or any other pipe bringing the space 25 into communication with an existing space downstream of the stage 20 where there is a pressure lower than the pressure P2 established at the outlet of the wheel 2.
  • FIG. 7 shows a fourth variant of the turbine according to the invention.
  • Stage 20 is identical to that shown in FIG. 1.
  • the upstream face 26 of the diaphragm 1 comprises second sealing means 31 spaced from the edge 15 which are applied against the ring 19 ⁇ of the stator located around the movable wheel 2 ⁇ of the previous stage 20 ⁇ .
  • the diaphragm 1 ⁇ of the previous stage is similar to that shown in Figure 4 and has a circular support 18 ⁇ coming to be applied by sealing against the crown 19 ⁇ of the stator. However, it does not include sealing means on the edge 15 ⁇ of the outer ring 3 ⁇ .
  • the space 25 ⁇ between stator 4 and diaphragm 1 ⁇ upstream of the support 18 ⁇ is at the pressure P0 upstream of the diaphragm 1 ⁇ while the space 25 is at the pressure downstream P2 of the stage 20 .
  • the ring 19 ⁇ is provided with openings 27 ⁇ connecting the space 25 ⁇ and the space 30 located between the sealing means 17 and the second sealing means 31.
  • the pressure difference P0 - P2 being more important than the difference P1 - P2, the force generated on the periphery of the upstream face 26 of the outer ring 3 will be greater.
  • FIG. 8 A variant of the device of Figure 7 is shown in Figure 8, the ring 19 ⁇ located above the movable wheel 2 ⁇ of the previous stage 20 ⁇ is narrower and surrounds a ring 33 secured to the diaphragm 1 ⁇ . This crown 33 is terminated by a support 18 ⁇ which is applied by sealing on the diaphragm 1.
  • the diaphragm 1 with the correction of stresses can have a thickness less than the diaphragm 1 cette where this correction is not made.
  • the stage 20 is identical to that of FIG. 7.
  • the space 30 instead of being connected to the space 25 ⁇ where the upstream pressure P0 of the diaphragm 1 ⁇ of the preceding stage prevails is joined by a communication 27 ′′′ to a space 25 ′′′ of one of the preceding stages 20 ′′′ Where there is a pressure P ′ greater than the pressure P0.
  • the force exerted on the upstream face 26 of the diaphragm 1 is therefore greater than that exerted in the device of FIG. 7 since the difference P ′ - P2 is greater than P0 - P2.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
  • Control Of Turbines (AREA)
  • Diaphragms For Electromechanical Transducers (AREA)
  • Diaphragms And Bellows (AREA)

Abstract

Turbine having at least one stage (20) with a diaphragm (1) cut in two along a diametral plane and comprising an outer ring (3) and an inner ring (6) connected by means (10) and (11) serving for guiding the fluid of the turbine, the downstream face (14) of the outer ring (3) being laid against a ring (19) of the stator (4) of the turbine, the said diaphragm (1) being equipped with sealing means (17) ensuring sealing between the outer ring (3) and the stator (4), characterised in that the said sealing means (17) are arranged on the edge (15) of the outer ring (3), in that the downstream face (14) of the said outer ring (3) is equipped with a bearing surface (18) located at a distance from the edge (15) and coming to bear on the ring (19) of the stator (4), and in that means (22, 27, 27') are provided for ensuring communication between the space (25) located between the bearing surface (18) and sealing means (17) and a space downstream of the diaphragm (1), the said space being at a pressure below the pressure P1 established on the upstream face (26) of the diaphragm (1). <IMAGE>

Description

1. ETAT DE LA TECHNIQUE ANTERIEURE1. STATE OF THE PRIOR ART

. Dans un étage de Turbine, le diaphragme (Figure 1) assure la détente du fluide soit totale (turbine à action) soit partielle (turbine à réaction) avant que celui-ci traverse la roue ailetée dans laquelle s'effectue le transfert d'énergie vers le rotor.. In a turbine stage, the diaphragm (Figure 1) ensures the expansion of the fluid, either total (action turbine) or partial (reaction turbine) before it crosses the finned wheel in which the energy transfer takes place. towards the rotor.

Le diaphragme est un élément capital par les fonctions qu'il assure :
- Détendre le fluide à travers les aubes directrices avec le meilleur rendement.
- Supporter les dispositifs d'étanchéité :
. au sommet des roues ailetées,
. au moyeu du rotor
- Maintenir en position relative radiale dans tous les cas de fonctionnement les aubes directrices par rapport aux ailettes de la roue.
- Supporter la différence de pression entre les faces amont et aval sans introduire dans les éléments mécaniques des contraintes et des flèches importantes.The diaphragm is a capital element by the functions it performs:
- Relax the fluid through the guide vanes with the best efficiency.
- Support the sealing devices:
. at the top of the finned wheels,
. to the rotor hub
- Keep the guide vanes in radial relative position in all operating cases with respect to the wheel fins.
- Support the pressure difference between the upstream and downstream faces without introducing significant constraints and deflections into the mechanical elements.

. Il faut savoir que des flèches importantes dans le sens axial de la turbine conduisent à des jeux axiaux importants et à une dégradation du rendement de l'étage.. It should be noted that large arrows in the axial direction of the turbine lead to large axial clearances and to a deterioration in the efficiency of the stage.

. De manière générale, un diaphragme est constitué : (Figure 1)
- Soit d'aubages distributeurs assurant à la fois le guidage et la détente du fluide le traversant et la liaison de sa frette extérieure avec son centre.
- Soit : d'une grille distributrice assurant la fonction guidage et détente de fluide la traversant, associée à des bras (ou ponts) placés en amont qui réalisent la liaison entre le centre et la frette du diaphragme.. Generally, a diaphragm is made up: (Figure 1)
- Either distributor vanes ensuring both the guiding and the expansion of the fluid passing through and the connection of its outer hoop with its center.
- Either: a distribution grid ensuring the guiding and expansion function of the fluid passing through it, associated with arms (or bridges) placed upstream which provide the connection between the center and the hoop of the diaphragm.

. La coupure du diaphragme, selon un plan diamètral nécessaire au montage, est source de contraintes élevées dans les ponts et les aubes situées au voisinage de celle-ci. De même, les flèches sont plus élevées près du plan de la coupure que dans le plan de symétrie perpendiculaire à celui-ci.. The cut of the diaphragm, according to a diametrical plane necessary for mounting, is a source of high stresses in the bridges and the blades located in the vicinity thereof. Likewise, the arrows are higher near the plane of the cut than in the plane of symmetry perpendicular to it.

. Pour réduire les contraintes et les flèches dans un diaphragme, on peut augmenter son épaisseur, ce qui conduit à augmenter la longueur de la machine dans laquelle sont montés des diaphragmes.. To reduce the stresses and deflections in a diaphragm, its thickness can be increased, which leads to increasing the length of the machine in which the diaphragms are mounted.

2. BUT DE L'INVENTION2. PURPOSE OF THE INVENTION

. Pour éviter d'augmenter l'épaisseur des diaphragmes, l'inventeur a eu l'idée de modifier la répartition des forces sur la face amont de la couronne extérieure du diaphragme.. To avoid increasing the thickness of the diaphragms, the inventor had the idea of modifying the distribution of the forces on the upstream face of the outer crown of the diaphragm.

3. PARTICULARITES DE L'INVENTION3. SPECIAL FEATURES OF THE INVENTION

L'invention permettant d'atteindre ce but est caractérisée en ce que :
. Les moyens d'étanchéité, entre le diaphragme et le stator le recevant, sont disposées sur la tranche de la couronne extérieure.
. La face aval de ladite couronne extérieure est munie d'un appui distant de la tranche et venant s'appuyer sur la couronne du stator.
. Des moyens sont prévus pour assurer une communication de l'espace situé entre appui et moyens d'étanchéité avec un espace en aval du diaphragme, ledit espace étant à une pression inférieure à la pression P₁ établie sur la face amont du diaphragme.
. Cet espace est à la pression P₂ aval de l'étage (P₂ < P₁) si bien qu'il s'y développe des forces appliquées sur la couronne en des points plus éloignés de l'axe du diaphragme que l'appui.
. La réduction de la contrainte dans les moyens de liaison entre le centre et la frette du diaphragme permet de diminuer les flèches de la partie centrale de la couronne intérieure, ce qui diminue les jeux axiaux et augmente le rendement de l'étage.The invention enabling this object to be achieved is characterized in that:
. The sealing means, between the diaphragm and the stator receiving it, are arranged on the edge of the outer ring.
. The downstream face of said outer ring is provided with a support remote from the edge and coming to bear on the crown of the stator.
. Means are provided for ensuring communication of the space between support and sealing means with a space downstream of the diaphragm, said space being at a pressure below the pressure P₁ established on the upstream face of the diaphragm.
. This space is at the pressure P₂ downstream of the stage (P₂ <P₁) so that there are developed forces applied to the crown at points farther from the axis of the diaphragm than the support.
. Reducing the stress in the connection means between the center and the diaphragm hoop makes it possible to reduce the arrows in the central part of the inner ring, which decreases the axial clearances and increases the efficiency of the stage.

4. DESCRIPTION DE L'INVENTION4. DESCRIPTION OF THE INVENTION

. Selon une première réalisation de l'invention, les moyens de communication sont constitués par des fentes prévues dans l'appui mettant ainsi l'espace situé entre appui et les moyens d'étanchéité à la pression P₂ de l'aval de l'étage comprenant le diaphragme.. According to a first embodiment of the invention, the communication means consist of slots provided in the support thus putting the space between support and the sealing means at the pressure P₂ downstream of the stage comprising the diaphragm.

. Selon une seconde réalisation de l'invention, les moyens de communication sont constitués par des ouvertures prévues dans la couronne de stator sur laquelle porte l'appui mettant ainsi l'espace situé entre l'appui et les moyens d'étanchéité à la pression P₂ de l'aval de l'étage mobile suivant l'étage avec le diaphragme.. According to a second embodiment of the invention, the communication means are constituted by openings provided in the stator ring on which the support bears, thus putting the space between the support and the pressure sealing means P₂ downstream of the mobile stage following the stage with the diaphragm.

. Selon une troisième réalisation de l'invention, l'espace situé entre l'appui et les moyens d'étanchéité sont reliés par des canalisations à un des étages plus en aval de la machine qui se trouve naturellement à une pression P inférieure à la pression P₂.. According to a third embodiment of the invention, the space between the support and the sealing means are connected by pipes to one of the stages further downstream of the machine which is naturally at a pressure P lower than the pressure P₂.

. Selon un perfectionnement de l'invention, la couronne extérieure du diaphragme comporte une partie de plus grand diamètre sur la tranche de laquelle sont disposés les moyens d'étanchéité. Ainsi, la force appliquée sur la partie amont de la couronne est plus importante.. According to an improvement of the invention, the outer ring of the diaphragm comprises a portion of larger diameter on the edge of which the sealing means are arranged. Thus, the force applied to the upstream part of the crown is greater.

. La partie de plus grand diamètre peut venir se loger entre les boulons de fixation du stator.. The part of larger diameter can be received between the stator fixing bolts.

. Selon un autre perfectionnement de l'invention, l'espace situé en amont des moyens d'étanchéité de la tranche de la couronne extérieure du diaphragme d'un des étages précédents.. According to another improvement of the invention, the space located upstream of the sealing means of the edge of the outer ring of the diaphragm of one of the preceding stages.

. L'invention va maintenant être décrite plus en détail en active des aubes 12 de la roue mobile 2 faisant partie du rotor 9. Des dispositifs d'étanchéité 13 sont fixés sur la face aval 14 du diaphragme 1 et entourent la roue mobile 2.. The invention will now be described in more detail in active mode of the vanes 12 of the movable wheel 2 forming part of the rotor 9. Sealing devices 13 are fixed on the downstream face 14 of the diaphragm 1 and surround the movable wheel 2.

Sur la tranche 15 de la couronne extérieure 3 est disposé dans une rainure 16 un dispositif d'étanchéité 17 qui est appliqué sur la paroi interne du stator pour faire étanchéité.On the edge 15 of the outer ring 3 is disposed in a groove 16 a sealing device 17 which is applied to the internal wall of the stator to seal.

Sur la face aval 14 de cette couronne extérieure 3 est disposé un appui circulaire 18 qui vient porter contre une couronne 19 du stator 4 situé autour de la roue 2 et des dispositifs d'étan­chéité 13.On the downstream face 14 of this outer ring 3 is disposed a circular support 18 which comes to bear against a ring 19 of the stator 4 located around the wheel 2 and sealing devices 13.

Cet appui 18 est situé le plus près possible du dispositif 13This support 18 is located as close as possible to the device 13

L'appui est muni de fentes 22 (voir figure 2).The support is provided with slots 22 (see FIG. 2).

Le diaphragme 1 est muni sur sa périphérie de deux encoches 23 au voisinage du plan de joint et d'une encoche 24 dans le bas.The diaphragm 1 is provided on its periphery with two notches 23 near the joint plane and a notch 24 at the bottom.

Les encoches 23 reçoivent comme il est classique des clavettes suspendant le diaphragme 1 dans le stator 4.The notches 23 receive, as is conventional, keys which suspend the diaphragm 1 in the stator 4.

L'encoche 24 reçoit également, d'une façon classique, une clavette complétant le guidage et assurant avec les clavettes des encoches 23, le montage à libre dilation.The notch 24 also receives, in a conventional manner, a key completing the guiding and ensuring with the keys of the notches 23, the assembly with free expansion.

L'espace 25 situé entre les moyens d'étanchéité 17 et l'appui 18 est mis par les fentes 22 en communication avec la pression P₂ régnant en aval de la roue 2.The space 25 located between the sealing means 17 and the support 18 is placed by the slots 22 in communication with the pressure P₂ prevailing downstream of the wheel 2.

La pression P₁ régnant en amont du diaphragme étant supérieure à la pression P₂, un effort est appliqué sur le pourtour de la face amont 26 de la couronne supérieure 3, il s'ensuit, que par effet de levier autour de l'appui 18, les contraintes vont diminuer dans les aubes 11 et les ponts 10 du canal vapeur 5. De même la flèche maximale, située au plan de joint et près du moyeu du rotor, va diminuer.The pressure P₁ prevailing upstream of the diaphragm being greater than the pressure P₂, a force is applied to the periphery of the upstream face 26 of the upper ring 3, it follows that, by leverage around the support 18, the stresses will decrease in the vanes 11 and the bridges 10 of the vapor channel 5. Similarly, the maximum deflection, located at the joint plane and near the hub of the rotor, will decrease.

Selon une variante de l'invention représentée à la figure 4, l'appui 18 ne comporte plus de fentes comme dans la réalisation de la figure 1 mais fait étanchéité avec la couronne 19 du sta­tor 4.According to a variant of the invention shown in FIG. 4, the support 18 no longer has slots as in the embodiment of FIG. 1 but seals with the crown 19 of the stator 4.

Cette couronne 19 est muni d'ouvertures transversales qui mettent l'espace 25 entre les moyens d'étanchéité 17 et l'appui 18 en communication avec l'aval de l'étage 20 à la pression P₂.This ring 19 is provided with transverse openings which place the space 25 between the sealing means 17 and the support 18 in communication with the downstream of the stage 20 at the pressure P₂.

Selon une autre variante représentée à la figure 5, l'appui 18 fait également étanchéité avec la couronne 19 et l'espace 25 entre les moyens d'étanchéité 17 et l'appui 18 est mis en communication par une canalisation 27′ avec un des étages suivants 20′ où règne naturellement une pression P inférieure à la pression P₂ établie à la sortie de l'étage 20.According to another variant shown in FIG. 5, the support 18 also seals with the crown 19 and the space 25 between the sealing means 17 and the support 18 is placed in communication by a pipe 27 ′ with one of the following stages 20 ′ where a pressure P naturally prevails lower than the pressure P₂ established at the outlet of stage 20.

Sur la figure 6, on a représenté une troisième variante dans laquelle la couronne extérieure 3 comporte une partie de plus grand diamètre 28 sur la tranche 29 de laquelle sont disposés les moyens d'étanchéité 17. Cette partie de plus grand diamètre a une épaisseur telle qu'elle peut se loger entre les boulons 32 servant au boulonnage du stator 4.In Figure 6, there is shown a third variant in which the outer ring 3 has a portion of larger diameter 28 on the edge 29 of which are arranged the sealing means 17. This portion of larger diameter has a thickness such that it can be housed between the bolts 32 used for bolting the stator 4.

L'espace 25 entre l'appui 18 et les moyens d'étanchéité 17 est mis en communication avec l'espace immédiatement en aval de l'étage 20 par des fentes prévues dans l'appui 18. On pourrait également utiliser les ouvertures 27 représentées à la figure 4 pour cette mise en communication ou toute autre canalisation mettant en communication l'espace 25 avec un espace existant en aval de l'étage 20 où règne une pression inférieure à la pression P₂ établie à la sortie de la roue 2.The space 25 between the support 18 and the sealing means 17 is placed in communication with the space immediately downstream of the stage 20 by slots provided in the support 18. The openings 27 shown could also be used in FIG. 4 for this connection or any other pipe bringing the space 25 into communication with an existing space downstream of the stage 20 where there is a pressure lower than the pressure P₂ established at the outlet of the wheel 2.

On peut ainsi, sans augmenter les dimensions du stator avoir une force sur la face amont 26 de la couronne extérieure 3 plus importante que dans les réalisations des figures 1 et 4.It is thus possible, without increasing the dimensions of the stator, to have a greater force on the upstream face 26 of the outer ring 3 than in the embodiments of FIGS. 1 and 4.

Sur la figure 7, on a représenté une quatrième variante de la turbine selon l'invention.FIG. 7 shows a fourth variant of the turbine according to the invention.

L'étage 20 est identique à celui représenté à la figure 1.Stage 20 is identical to that shown in FIG. 1.

Toutefois, la face amont 26 du diaphragme 1 comporte des seconds moyens d'étanchéité 31 écartés de la tranche 15 qui viennent s'appliquer contre la couronne 19˝ du stator située autour de la roue mobile 2˝ de l'étage précédent 20˝.However, the upstream face 26 of the diaphragm 1 comprises second sealing means 31 spaced from the edge 15 which are applied against the ring 19˝ of the stator located around the movable wheel 2˝ of the previous stage 20˝.

Le diaphragme 1˝ de l'étage précédent est semblable à celui représenté à la figure 4 et comporte un appui circulaire 18˝ venant s'appliquer en faisant étanchéité contre la couronne 19˝ du stator. Toutefois, il ne comporte pas de moyens d'étanchéité sur la tranche 15˝ de la couronne extérieure 3˝. Ainsi, l'espace 25˝ entre stator 4 et diaphragme 1˝ en amont de l'appui 18˝ est à la pression P₀ en amont du diaphragme 1˝ tandis que l'espace 25 est à la pression aval P₂ de l'étage 20.The diaphragm 1˝ of the previous stage is similar to that shown in Figure 4 and has a circular support 18˝ coming to be applied by sealing against the crown 19˝ of the stator. However, it does not include sealing means on the edge 15˝ of the outer ring 3˝. Thus, the space 25˝ between stator 4 and diaphragm 1˝ upstream of the support 18˝ is at the pressure P₀ upstream of the diaphragm 1˝ while the space 25 is at the pressure downstream P₂ of the stage 20 .

La couronne 19˝ est munie d'ouvertures 27˝ mettant en communica­tion l'espace 25˝ et l'espace 30 situés entre les moyens d'étanchéité 17 et les seconds moyens d'étanchéité 31. La différence de pression P₀ - P₂ étant plus importante que la différence P₁ - P₂, la force générée sur le pourtour de la face amont 26 de la couronne extérieure 3 sera plus importante.The ring 19˝ is provided with openings 27˝ connecting the space 25˝ and the space 30 located between the sealing means 17 and the second sealing means 31. The pressure difference P₀ - P₂ being more important than the difference P₁ - P₂, the force generated on the periphery of the upstream face 26 of the outer ring 3 will be greater.

Une variante du dispositif de la figure 7 est représentée à la figure 8, la couronne 19˝ située au-dessus de la roue mobile 2˝ de l'étage précédent 20˝ est moins large et entoure une couronne 33 solidaire du diaphragme 1˝. Cette couronne 33 est terminée par un appui 18˝ qui vient s'appliquer en faisant étanchéité sur le diaphragme 1.A variant of the device of Figure 7 is shown in Figure 8, the ring 19˝ located above the movable wheel 2˝ of the previous stage 20˝ is narrower and surrounds a ring 33 secured to the diaphragm 1˝. This crown 33 is terminated by a support 18˝ which is applied by sealing on the diaphragm 1.

Grâce au passage 34 laissé libre entre la couronne 33 et la couronne 19˝, l'espace 30 compris entre les moyens d'étanchéité 17 et l'appui 18˝ est mis à la pression amont P₀ du diaphragme 1˝ de l'étage précédent 20˝.Thanks to the passage 34 left free between the crown 33 and the crown 19˝, the space 30 between the sealing means 17 and the support 18˝ is brought to the upstream pressure P₀ of the diaphragm 1˝ of the previous stage 20˝.

Le diaphragme 1 avec la correction de contraintes peut avoir une épaisseur moindre que le diaphragme 1˝ où cette correction n'est pas faite.The diaphragm 1 with the correction of stresses can have a thickness less than the diaphragm 1 cette where this correction is not made.

Selon une autre variante du dispositif de la figure 7 représenté à la figure 9, l'étage 20 est identique à celui de la figure 7.According to another variant of the device of FIG. 7 represented in FIG. 9, the stage 20 is identical to that of FIG. 7.

L'espace 30 au lieu d'être relié à l'espace 25˝ où règne la pression amont P₀ du diaphragme 1˝ de l'étage précédent est réuni par une communication 27‴ à un espace 25‴ d'un des étages précédents 20‴ où règne und pression P′ supérieure à la pression P₀.The space 30 instead of being connected to the space 25˝ where the upstream pressure P₀ of the diaphragm 1˝ of the preceding stage prevails is joined by a communication 27 ‴ to a space 25 ‴ of one of the preceding stages 20 ‴ Where there is a pressure P ′ greater than the pressure P₀.

La force exercée sur la face amont 26 du diaphragme 1 est donc supérieure à celle exercée dans le dispositif de la figure 7 puisque la différence P′ - P₂ est supérieure à P₀ - P₂.The force exerted on the upstream face 26 of the diaphragm 1 is therefore greater than that exerted in the device of FIG. 7 since the difference P ′ - P₂ is greater than P₀ - P₂.

Claims (6)

1/ Turbine comportant au moins un étage 20 avec un diaphragme (1) coupé en deux selon plan diamétral et comprenant une couronne extérieure (3) et une couronne intérieure (6) réunies par des moyens (10) et (11) servant au guidage du fluide de la turbine, la face aval (14) de la couronne extérieure (3) étant appliquée contre une couronne (19) du stator (4) de la turbine, ledit diaphragme (1) étant muni de moyens d'étanchéité (17) assurant l'étanchéité entre la couronne extérieure (3) et le stator (4) caractérisé en ce que lesdits moyens d'étanchéité (17) sont disposés sur la tranche (15) de la couronne extérieure (3), en ce que la face aval (14) de ladite couronne extérieure (3) est munie d'un appui (18) distant de la tranche (15) et venant s'appuyer sur la couronne (19) du stator (4) et en ce que des moyens (22, 27, 27′) sont prévus pour assurer une communication de l'espace (25) situé entre appui (18) et moyens d'étanchéité (17) avec un espace en aval du diaphragme (1), ledit espace étant à une pression inférieure à la pression P₁ établie sur la face amont (26) du diaphragme (1).1 / Turbine comprising at least one stage 20 with a diaphragm (1) cut in two according to diametrical plane and comprising an outer ring (3) and an inner ring (6) joined by means (10) and (11) used for guiding of the turbine fluid, the downstream face (14) of the outer ring (3) being applied against a ring (19) of the stator (4) of the turbine, said diaphragm (1) being provided with sealing means (17 ) ensuring the seal between the outer ring (3) and the stator (4) characterized in that said sealing means (17) are arranged on the edge (15) of the outer ring (3), in that the downstream face (14) of said outer ring (3) is provided with a support (18) distant from the edge (15) and coming to bear on the ring (19) of the stator (4) and in that means (22, 27, 27 ′) are provided to ensure communication of the space (25) located between support (18) and sealing means (17) with a space downstream of the diaphragm (1), said space being at a pressure lower than the pressure P₁ established on the upstream face (26) of the diaphragm (1). 2/ Turbine, selon la revendication 1, caractérisé en ce que lesdits moyens de communication sont constitués par des fentes (22) prévues dans l'appui (18).2 / turbine, according to claim 1, characterized in that said communication means are constituted by slots (22) provided in the support (18). 3/ Turbine, selon la revendication 1, caractérisé en ce que lesdits moyens de communication sont constitués par des ouvertures (27) prévues dans la couronne (19) du stator (4) sur laquelle porte l'appui (18).3 / turbine, according to claim 1, characterized in that said communication means are constituted by openings (27) provided in the crown (19) of the stator (4) on which bears the support (18). 4/ Turbine, selon la revendication 1, caractérisé en ce que les moyens de communication sont constitués par des canalisations (27′) assurant une communication dudit espace (25) avec un étage (20′) en aval de l'étage (20) où règne une pression P inférieure à la pression P₂ régnant en aval de l'étage (20).4 / turbine, according to claim 1, characterized in that the communication means are constituted by pipes (27 ′) ensuring communication of said space (25) with a stage (20 ′) downstream of the stage (20) where there is a pressure P lower than the pressure P₂ prevailing downstream of the stage (20). 5/ Turbine, selon l'une des revendications précédentes, caractérisé en ce que la couronne extérieure (3) du diaphragme (1) comporte une partie (28) de plus grand diamètre sur la tranche (29) de laquelle sont disposés les moyens d'étanchéité (17).5 / turbine, according to one of the preceding claims, characterized in that the outer ring (3) of the diaphragm (1) has a portion (28) of larger diameter on the edge (29) of which are arranged the means d 'sealing (17). 6/ Turbine, selon l'une des revendications précédentes, caractérisé en ce que l'espace (30) situé en amont des moyens d'étanchéité (17) de la tranche (15) de la couronne extérieure (3) du diaphragme (1) est isolé de la pression P₁ qui règne en amont du diaphragme (1) par des seconds moyens d'étanchéité (31, 18˝) situés sur la face amont (26) du diaphragme (1) à distance de la tranche (15), ledit espace (30) étant mis en communication avec un des espaces en amont de l'étage précédent dans lequel la pression est supérieure à la pression P₁.6 / turbine, according to one of the preceding claims, characterized in that the space (30) located upstream of the sealing means (17) of the edge (15) of the outer ring (3) of the diaphragm (1 ) is isolated from the pressure P₁ which prevails upstream of the diaphragm (1) by second sealing means (31, 18˝) located on the upstream face (26) of the diaphragm (1) at a distance from the edge (15) , said space (30) being placed in communication with one of the spaces upstream from the previous stage in which the pressure is greater than the pressure P₁.
EP89118211A 1988-10-06 1989-10-02 Device for reducing stresses and deflections in turbine diaphragms Expired - Lifetime EP0362756B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT89118211T ATE78320T1 (en) 1988-10-06 1989-10-02 STRUCTURAL DESIGN OF A TURBINE FLOOR TO PREVENT STRESS AND DEFLECTION.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8813117A FR2637650B1 (en) 1988-10-06 1988-10-06 DEVICES FOR REDUCING ARROWS AND STRESSES IN TURBINE DIAPHRAGMS
FR8813117 1988-10-06

Publications (2)

Publication Number Publication Date
EP0362756A1 true EP0362756A1 (en) 1990-04-11
EP0362756B1 EP0362756B1 (en) 1992-07-15

Family

ID=9370749

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Application Number Title Priority Date Filing Date
EP89118211A Expired - Lifetime EP0362756B1 (en) 1988-10-06 1989-10-02 Device for reducing stresses and deflections in turbine diaphragms

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US (1) US5024581A (en)
EP (1) EP0362756B1 (en)
JP (1) JPH02146205A (en)
CN (1) CN1013508B (en)
AT (1) ATE78320T1 (en)
CS (1) CS568089A3 (en)
DE (1) DE68902124T2 (en)
ES (1) ES2034548T3 (en)
FR (1) FR2637650B1 (en)
GR (1) GR3005956T3 (en)
MX (1) MX170952B (en)
ZA (1) ZA897626B (en)

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RU186946U1 (en) * 2018-11-08 2019-02-11 Акционерное общество "Уральский турбинный завод" Device for controlling the flow rate of the working fluid of a heat engine

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GB0319002D0 (en) * 2003-05-13 2003-09-17 Alstom Switzerland Ltd Improvements in or relating to steam turbines
US7637081B2 (en) 2003-08-27 2009-12-29 Niikura Scales Co., Ltd. Article storage device
GB2417298B (en) * 2004-08-21 2008-12-24 Alstom Technology Ltd Sealing arrangement
ES2285915B1 (en) * 2005-10-11 2008-10-16 Airbus España, S.L. SEALING SYSTEM OF VARIABLE SLOTS FOR MACHINES TESTED IN AN AERODYNAMIC TUNNEL.
US7758307B2 (en) * 2007-05-17 2010-07-20 Siemens Energy, Inc. Wear minimization system for a compressor diaphragm
DE102014221152A1 (en) * 2014-10-17 2016-04-21 Siemens Aktiengesellschaft Sealing of a sealing cup suspension
FR3036435B1 (en) * 2015-05-22 2020-01-24 Safran Ceramics TURBINE RING ASSEMBLY

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Also Published As

Publication number Publication date
DE68902124D1 (en) 1992-08-20
CS568089A3 (en) 1992-10-14
FR2637650A1 (en) 1990-04-13
JPH02146205A (en) 1990-06-05
DE68902124T2 (en) 1992-12-17
ATE78320T1 (en) 1992-08-15
CN1042967A (en) 1990-06-13
GR3005956T3 (en) 1993-06-07
ZA897626B (en) 1990-07-25
ES2034548T3 (en) 1993-04-01
US5024581A (en) 1991-06-18
FR2637650B1 (en) 1990-11-16
EP0362756B1 (en) 1992-07-15
MX170952B (en) 1993-09-22
CN1013508B (en) 1991-08-14

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