EP0394894B1 - One piece internal casing for a hp-mp steamturbine with controlled cooling - Google Patents

One piece internal casing for a hp-mp steamturbine with controlled cooling Download PDF

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Publication number
EP0394894B1
EP0394894B1 EP90107617A EP90107617A EP0394894B1 EP 0394894 B1 EP0394894 B1 EP 0394894B1 EP 90107617 A EP90107617 A EP 90107617A EP 90107617 A EP90107617 A EP 90107617A EP 0394894 B1 EP0394894 B1 EP 0394894B1
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EP
European Patent Office
Prior art keywords
stator
stream
steam
internal
space
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Expired - Lifetime
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EP90107617A
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German (de)
French (fr)
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EP0394894A1 (en
Inventor
Jean-Pierre Gros
Patrick Laffont
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Alstom Holdings SA
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GEC Alsthom SA
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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
    • F01D9/00—Stators
    • 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
    • F01D25/26—Double casings; Measures against temperature strain in casings
    • 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
    • F01D25/08—Cooling; Heating; Heat-insulation
    • F01D25/12—Cooling

Definitions

  • the present invention relates to an HP-MP steam turbine body according to the preamble of claim 1.
  • the internal stators HP (high pressure) and MP (medium pressure) are separated by an interval and each provided with a sealing device separated from each other and having the function of reducing the natural leakage of vapor from the HP vein to the MP vein.
  • a turbine of this type is described in document CH-A-435 319. Part of the leak passes in the gap between the two sealing devices and is evacuated by the gap formed between the two internal stators in the interstatoric space; this space is thus swept by steam at high temperature, its evacuation taking place through the thermal protection means.
  • the vapor sweep in the interstatoric space thus traverses the entire space, from the axial positioning means to the thermal protection means.
  • the evacuation means are provided with means for adapting the vapor flow rate, which makes it possible to adapt the air conditioning to the desired level.
  • the means for evacuating this vapor are connected to the inlet of the reheating device supplying the vein MP.
  • At least part of the surface of the internal stator facing the rotor between the HP and MP veins is provided with a coating with low thermal conductivity.
  • the means for withdrawing steam sending this steam into the interstatoric space are constituted by pipes formed in bosses of the internal stator arranged symmetrically with respect to the axis of the turbine.
  • the external stator is thus protected from too strong convections.
  • Figure 1 shows in axial half-section a known HP-MP turbine body.
  • Figure 2 shows in axial half-section an HP-MP turbine body according to the invention.
  • FIG. 3 represents a detailed axial half-section of a preferred embodiment of the invention.
  • FIG. 4 represents a partial section along the plane IV-IV of the body of FIG. 3.
  • FIG. 5 represents a partial section along the plane V-V of the body of FIG. 3.
  • FIG. 6 represents a perspective of the detail of the body represented in FIG. 5.
  • the known turbine body shown in FIG. 1 comprises a single rotor 1 comprising an HP part 2 and an MP part 3 separated by a part 4 receiving the seals.
  • An internal HP stator 5 defines with HP part 2 an HP vein 6.
  • An internal MP 7 stator defines with the MP 3 part an MP 8 vein.
  • the two internal stators 5 and 7 are interconnected. They are positioned axially inside an external stator 9 by sealed positioning means 11.
  • an HP exhaust 15 connected through a reheating device 16 to MP intake means 17 which supply the inlet 18 of the MP stream 8.
  • the external stator 9 and the internal stators 5 and 7 define with the positioning means 11 and the thermal screen 10 an interstatoric space 19.
  • the axial positioning means 11 and the heat shield 10 are spaced from the inlets 12 and 18 of the HP 6 and MP 8 veins, so that the interstatoric space 19 surrounds all of the hot stages of the HP 6 and MP 8 veins .
  • seals 20 and 21 are arranged to separate the inlet 12 of the HP vein 6 from the inlet 18 of the vein 8.
  • the vapor entered through the interval 22 escapes towards the outlet 14 of the HP vein 6 through a slot 23 formed in the screen 10.
  • the HP-MP turbine body according to the invention is shown in FIG. 2.
  • the body according to the invention comprises a single internal stator 57.
  • the sealing means 20, 21 arranged in part 4 are in one piece.
  • the axial positioning means 11 are sealed and likewise the thermal protection means 10 are also sealed.
  • the interstatoric space 19 surrounds almost all of the stages of the HP vein 6 and the hot stages of the MP vein 8.
  • An inlet 24 into the interstatoric space is provided in the internal stator 57 in the vicinity of the thermal protection means 10. This inlet brings into the space 19 the vapor drawn off from one of the last stages of the HP vein 6 , for example, upstream of the last stage 25.
  • an outlet 26 connected to the HP exhaust 15 by a pipe 28 provided with an adaptation device 27.
  • This device is for example a pierced plate or a valve.
  • the adaptation member 27 the temperature distribution along the axis can be adjusted more precisely.
  • the members 27 By adjusting the members 27 differently, the cooling of the interstatoric space 19 can be adjusted. azimuth.
  • the vapor flow sweeping the interstatoric space optimally cools the internal 57 and external 9 stators, which makes it possible to have a low thermal gradient at the level of the internal body 57 as well as low temperatures of bolts and external stator. This makes it possible to have a smaller dimensioning of the bolts and of the external stator 9.
  • the tightness of the thermal protection device 10 protects the hot parts from any random entry of cold vapor coming from the exit from the HP vein.
  • the part of the internal stator 57 is coated in the vicinity of the inlet 12 of the HP stream 6 with a coating 29 of low thermal conductivity. Likewise, the part of the internal stator 57 in the vicinity of the inlet 18 of the vein MP 8 is provided with a coating 29 with low thermal conductivity.
  • the internal stator 57 in the vicinity of the thermal protection means 10 includes bosses 30. Lateral pipes 31, 32 and a radial pipe 33 are provided in each boss (see fig.4) .
  • the pipes 31, 32, 33 are supplied by a socket 34 located in the HP stream 6 and open into the interstatoric space 19 in the vicinity of the thermal protection means 10.
  • the bosses 30 are symmetrical with respect to the axis of the turbine.
  • the axial positioning means 11 consist of a first part 35 secured to the internal stator 57, resting on a part 36 secured to the external stator 9 between a support 37 and a counter-support 38.
  • Grooves 39 have been made in the part 35 and open into a cavity 40 of the part 36.
  • a chimney 41 opening into the cavity 40 is formed in the external stator 9.
  • Each chimney 41 is provided with a plunging pipe 42 serving to evacuate the steam to the flow control device 27 (figure 2). These pipes 42 protect the external stator 9 from too much convection.
  • each of these pipes 42 evacuates the steam to a flow adaptation device 27.
  • each of the adaptation devices 27 By adjusting each of the adaptation devices 27, it is possible to adjust the cooling in azimuth in the interstatoric space 19.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
  • Engine Equipment That Uses Special Cycles (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Control Of Turbines (AREA)

Abstract

HP-MP steam-turbine body comprising a single inner stator (57) surrounding the HP part (2) and MP part (3) of the rotor. The inner stator (57) defines with the outer stator (9) means (11) for the axial positioning of the inner stator (57), and a thermal screen (10) defines an inter-stator space (19) swept by the steam taken from one of the last stages (25) of the HP section (6). <??>The parts of the inner stator which surround the entire expansion sector of the HP section (6) and the hot stages of the MP section (8) are thus air-conditioned to an optimum degree, thereby making it possible to reduce the thermal gradient supported by the inner stator (57) and the temperature of the bolts of the stators (57) and (9). <IMAGE>

Description

La présente invention concerne un corps de turbine à vapeur HP-MP selon le préambule de la revendication 1.The present invention relates to an HP-MP steam turbine body according to the preamble of claim 1.

Dans le corps de turbine connu les stators internes HP (haute pression) et MP (moyenne pression) sont séparés par un intervalle et munis chacun d'un dispositif d'étanchéité séparés l'un de l'autre et ayant pour fonction de réduire la fuite naturelle de vapeur de la veine HP vers la veine MP. Une turbine de ce type est décrit dans le document CH-A-435 319. Une partie de la fuite passe dans l'intervalle entre les deux dispositifs d'étanchéité et est évacuée par l'intervalle ménagé entre les deux stators internes dans l'espace interstatorique ; cet espace est ainsi balayé par de la vapeur à haute température, son évacuation se faisant à travers les moyens de protection thermique.In the known turbine body the internal stators HP (high pressure) and MP (medium pressure) are separated by an interval and each provided with a sealing device separated from each other and having the function of reducing the natural leakage of vapor from the HP vein to the MP vein. A turbine of this type is described in document CH-A-435 319. Part of the leak passes in the gap between the two sealing devices and is evacuated by the gap formed between the two internal stators in the interstatoric space; this space is thus swept by steam at high temperature, its evacuation taking place through the thermal protection means.

Grâce à cette circulation de vapeur, on climatise les stators interne et externe permettant ainsi d'abaisser la température du stator externe ce qui permet de réduire ses dimensions.Thanks to this circulation of steam, the internal and external stators are conditioned, thereby lowering the temperature of the external stator, which makes it possible to reduce its dimensions.

Mais la climatisation réalisée ainsi par le balayage de vapeur est imparfaite. En effet, la température de la vapeur injectée dans l'espace interstatorique est élevée et donc le stator externe ainsi que la boulonnerie des stators internes HP et MP sont à une température élevée.But the air conditioning achieved by the steam sweep is imperfect. Indeed, the temperature of the vapor injected into the interstatoric space is high and therefore the external stator as well as the bolts of the internal stators HP and MP are at a high temperature.

Le corps de turbine selon l'invention ne présentant pas ces inconvénients est défini par la partie caractérisante de la revendication 1.The turbine body according to the invention which does not have these drawbacks is defined by the characterizing part of claim 1.

En prélevant de la vapeur à plus faible température pour climatiser les stators interne et externe, au niveau d'un étage de la veine HP, on peut diminuer la température supportée par le stator externe ainsi que la température supportée par le boulonnage du stator externe et du stator interne HP-MP.By taking steam at a lower temperature to cool the internal and external stators, at the level of a stage of the HP vein, we can reduce the temperature supported by the external stator as well as the temperature supported by the bolting of the external stator and of the internal stator HP-MP.

Le balayage de vapeur dans l'espace interstatorique parcourt ainsi la totalité de l'espace, des moyens de positionnement axial aux moyens de protection thermique.The vapor sweep in the interstatoric space thus traverses the entire space, from the axial positioning means to the thermal protection means.

Enfin, comme il n'y a plus d'intervalle entre stator interne HP et stator interne MP, ces deux stators sont remplacés par un stator unique interne permettant de diminuer l'encombrement axial.Finally, as there is no longer any interval between internal HP stator and internal MP stator, these two stators are replaced by a single internal stator allowing the axial dimensions to be reduced.

Les moyens d'évacuation sont munis de moyens d'adaptation du débit de vapeur ce qui permet d'adapter la climatisation au niveau voulu.The evacuation means are provided with means for adapting the vapor flow rate, which makes it possible to adapt the air conditioning to the desired level.

Les moyens d'évacuation de cette vapeur sont reliés à l'entrée du dispositif de resurchauffe alimentant la veine MP.The means for evacuating this vapor are connected to the inlet of the reheating device supplying the vein MP.

Selon un perfectionnement de l'invention, au moins une partie de la surface du stator interne en regard du rotor entre les veines HP et MP est munie d'un revêtement à faible conductibilité thermique.According to an improvement of the invention, at least part of the surface of the internal stator facing the rotor between the HP and MP veins is provided with a coating with low thermal conductivity.

On diminue ainsi les contraintes thermiques transmises au stator interne dans la partie la plus chaude des veines HP et MP.This reduces the thermal stresses transmitted to the internal stator in the hottest part of the HP and MP veins.

Selon une réalisation préférentielle de l'invention, les moyens de prélèvement de vapeur envoyant cette vapeur dans l'espace interstatorique sont constitués par des canalisations ménagées dans des bossages du stator interne disposés symétriquement par rapport à l'axe de la turbine.According to a preferred embodiment of the invention, the means for withdrawing steam sending this steam into the interstatoric space are constituted by pipes formed in bosses of the internal stator arranged symmetrically with respect to the axis of the turbine.

Les moyens d'évacuation de vapeur de l'espace interstatorique comportent :

  • des rainures ménagées dans la partie des moyens de positionnement axial solidaires du stator interne et débouchant dans des cavités ménagées dans la partie des moyens de positionnement axial solidaires du stator externe,
  • des cheminées traversant le stator externe débouchant dans lesdites cavités, lesdites cheminées étant munies de tuyauteries plongeantes reliées à l'entrée du dispositif de resurchauffe.
The means for evacuating vapor from the interstatoric space include:
  • grooves formed in the part of the axial positioning means integral with the internal stator and opening into cavities formed in the part of the axial positioning means integral with the external stator,
  • chimneys passing through the external stator opening into said cavities, said chimneys being provided with plunging pipes connected to the inlet of the reheating device.

Le stator externe est ainsi protégé des trop fortes convections.The external stator is thus protected from too strong convections.

La présente invention sera mieux comprise à la lumière de la description qui va suivre dans laquelle :The present invention will be better understood in the light of the description which follows in which:

La figure 1 représente en demi-coupe axiale un corps de turbine HP-MP connu.Figure 1 shows in axial half-section a known HP-MP turbine body.

La figure 2 représente en demi-coupe axiale un corps de turbine HP-MP selon l'invention.Figure 2 shows in axial half-section an HP-MP turbine body according to the invention.

La figure 3 représente une demi-coupe axiale détaillée d'une réalisation préférentielle de l'invention.FIG. 3 represents a detailed axial half-section of a preferred embodiment of the invention.

La figure 4 représente une coupe partielle selon le plan IV-IV du corps de la figure 3.FIG. 4 represents a partial section along the plane IV-IV of the body of FIG. 3.

La figure 5 représente une coupe partielle selon le plan V-V du corps de la figure 3.FIG. 5 represents a partial section along the plane V-V of the body of FIG. 3.

La figure 6 représente une perspective du détail du corps représenté à la figure 5.FIG. 6 represents a perspective of the detail of the body represented in FIG. 5.

Le corps de turbine connu représenté à la figure 1 comporte un rotor unique 1 comprenant une partie HP 2 et une partie MP 3 séparées par une partie 4 recevant les étanchéités.The known turbine body shown in FIG. 1 comprises a single rotor 1 comprising an HP part 2 and an MP part 3 separated by a part 4 receiving the seals.

Un stator interne HP 5 définit avec la partie HP 2 une veine HP 6.An internal HP stator 5 defines with HP part 2 an HP vein 6.

Un stator interne MP 7 définit avec la partie MP 3 une veine MP 8.An internal MP 7 stator defines with the MP 3 part an MP 8 vein.

Les deux stators internes 5 et 7 sont reliés entre eux. Ils sont positionnés axialement à l'intérieur d'un stator externe 9 par des moyens de positionnement 11 étanches.The two internal stators 5 and 7 are interconnected. They are positioned axially inside an external stator 9 by sealed positioning means 11.

D'autre part, les parties chaudes des stators internes HP 5 et MP 7 sont protégés thermiquement par un écran 10 non étanche.On the other hand, the hot parts of the internal HP 5 and MP 7 stators are thermally protected by a non-waterproof screen 10.

La vapeur est injectée à l'entrée 12 de la veine HP 6 par des moyens d'admission 13.Steam is injected at the inlet 12 of the HP vein 6 by intake means 13.

A la sortie 14 de la veine HP 6 est disposé un échappement HP 15 relié à travers un dispositif de resurchauffe 16 à des moyens d'admission MP 17 qui alimentent l'entrée 18 de la veine MP 8.At the outlet 14 of the HP stream 6 is disposed an HP exhaust 15 connected through a reheating device 16 to MP intake means 17 which supply the inlet 18 of the MP stream 8.

Le stator externe 9 et les stators internes 5 et 7 définissent avec les moyens de positionnement 11 et l'écran thermique 10 un espace interstatorique 19.The external stator 9 and the internal stators 5 and 7 define with the positioning means 11 and the thermal screen 10 an interstatoric space 19.

Les moyens de positionnement axial 11 et l'écran thermique 10 sont écartés des entrées 12 et 18 des veines HP 6 et MP 8, de façon à ce que l'espace interstatorique 19 entoure la totalité des étages chauds des veines HP 6 et MP 8.The axial positioning means 11 and the heat shield 10 are spaced from the inlets 12 and 18 of the HP 6 and MP 8 veins, so that the interstatoric space 19 surrounds all of the hot stages of the HP 6 and MP 8 veins .

Au droit de la partie 4 sont disposées des garnitures d'étanchéité 20 et 21 pour séparer l'entrée 12 de la veine HP 6 de l'entrée 18 de la veine 8.In line with part 4, seals 20 and 21 are arranged to separate the inlet 12 of the HP vein 6 from the inlet 18 of the vein 8.

Ces deux garnitures 20, 21 sont écartées axialement par un intervalle 22 entre les stators internes 5 et 7 pour permettre l'alimentation en vapeur de l'espace interstatorique 19.These two linings 20, 21 are axially spaced apart by a gap 22 between the internal stators 5 and 7 to allow the supply of steam to the interstatoric space 19.

La vapeur entrée par l'intervalle 22 s'échappe vers la sortie 14 de la veine HP 6 par une fente 23 ménagée dans l'écran 10.The vapor entered through the interval 22 escapes towards the outlet 14 of the HP vein 6 through a slot 23 formed in the screen 10.

Cette vapeur climatise les stators interne et externe ce qui permet de diminuer le gradient de température supporté par les stators internes 5 et 7 et donc les sollicitations.This vapor air conditioning the internal and external stators which makes it possible to reduce the temperature gradient supported by the internal stators 5 and 7 and therefore the stresses.

Toutefois, en raison de la température élevée de la vapeur injectée le stator externe 9 ainsi que la boulonnerie des stators internes sont à une température élevée.However, due to the high temperature of the injected vapor, the external stator 9 as well as the bolts of the internal stators are at a high temperature.

D'autre part, l'expérience montre que la vapeur froide venant de l'échappement HP passe au delà de l'écran thermique 10 vers l'espace interstatorique 19 et crée une dissymétrie dans les températures ainsi que des contraintes dans les parties chaudes des stators internes HP et MP.On the other hand, experience shows that the cold vapor coming from the HP exhaust passes beyond the heat shield 10 towards the interstatoric space 19 and creates an asymmetry in the temperatures as well as stresses in the hot parts of the HP and MP internal stators.

Le corps de turbine HP-MP selon l'invention est représenté à la figure 2.The HP-MP turbine body according to the invention is shown in FIG. 2.

Les éléments constitutifs de ce corps semblables à ceux du corps connu représenté à la figure 1 portent les mêmes références.The constituent elements of this body similar to those of the known body shown in Figure 1 have the same references.

Le corps selon l'invention comporte un stator interne unique 57. Les moyens d'étanchéité 20, 21 disposés dans la partie 4 sont d'une seule pièce.The body according to the invention comprises a single internal stator 57. The sealing means 20, 21 arranged in part 4 are in one piece.

Les moyens de positionnement axial 11 sont étanches et de même les moyens de protection thermique 10 sont également étanches.The axial positioning means 11 are sealed and likewise the thermal protection means 10 are also sealed.

L'espace interstatorique 19 entoure la quasi totalité des étages de la veine HP 6 et les étages chauds de la veine MP 8.The interstatoric space 19 surrounds almost all of the stages of the HP vein 6 and the hot stages of the MP vein 8.

Une admission 24 dans l'espace interstatorique est ménagée dans le stator interne 57 au voisinage des moyens de protection thermique 10. Cette admission amène dans l'espace 19 la vapeur soutirée à la sortie de l'un des derniers étages de la veine HP 6, par exemple, en amont du dernier étage 25.An inlet 24 into the interstatoric space is provided in the internal stator 57 in the vicinity of the thermal protection means 10. This inlet brings into the space 19 the vapor drawn off from one of the last stages of the HP vein 6 , for example, upstream of the last stage 25.

Dans le stator externe 9 est ménagée une évacuation 26 reliée à l'échappement HP 15 par une canalisation 28 munie d'un dispositif d'adaptation 27. Ce dispositif est par exemple une plaque percée ou une vanne.In the external stator 9 is provided an outlet 26 connected to the HP exhaust 15 by a pipe 28 provided with an adaptation device 27. This device is for example a pierced plate or a valve.

La vapeur qui s'échappe de l'espace interstatorique est ainsi recyclée dans le dispositif de resurchauffe 16.The vapor which escapes from the interstatoric space is thus recycled to the reheating device 16.

En choisissant l'étage de la veine HP sur lequel on prélève de la vapeur, on peut obtenir l'ordre de grandeur voulu pour la température de la vapeur balayant l'espace interstatorique 19.By choosing the stage of the HP vein from which steam is taken, it is possible to obtain the desired order of magnitude for the temperature of the steam sweeping through the interstatoric space 19.

Grâce à l'organe d'adaptation 27, on peut régler avec plus de précision la distribution de température le long de l'axe. En général on aura plusieurs évacuations 26 disposées symétriquement autour de l'axe, chacune étant reliée à une canalisation 28 munie d'un organe d'adaptation 27. En réglant différemment les organes 27 on peut régler le refroidissement de l'espace interstatorique 19 en azimut.Thanks to the adaptation member 27, the temperature distribution along the axis can be adjusted more precisely. In general, there will be several outlets 26 arranged symmetrically about the axis, each being connected to a pipe 28 provided with an adaptation member 27. By adjusting the members 27 differently, the cooling of the interstatoric space 19 can be adjusted. azimuth.

Ainsi le débit de vapeur balayant l'espace interstatorique climatise de façon optimale les stators interne 57 et externe 9 ce qui permet d'avoir un gradient thermique faible au niveau du corps interne 57 ainsi que des températures basses de boulons et de stator externe. Ceci permet d'avoir un dimensionnement plus faible des boulons et du stator externe 9.Thus, the vapor flow sweeping the interstatoric space optimally cools the internal 57 and external 9 stators, which makes it possible to have a low thermal gradient at the level of the internal body 57 as well as low temperatures of bolts and external stator. This makes it possible to have a smaller dimensioning of the bolts and of the external stator 9.

D'autre part, l'étanchéité du dispositif de protection thermique 10 protège les parties chaudes de toute entrée aléatoire de vapeur froide venant de la sortie de la veine HP.On the other hand, the tightness of the thermal protection device 10 protects the hot parts from any random entry of cold vapor coming from the exit from the HP vein.

De plus, la construction du stator interne est plus simple.In addition, the construction of the internal stator is simpler.

On revêt la partie du stator interne 57 au voisinage de l'entrée 12 de la veine HP 6 d'un revêtement 29 à faible conductibilité thermique. De même, la partie du stator interne 57 au voisinage de l'entrée 18 de la veine MP 8 est pourvue d'un revêtement 29 à faible conductibilité thermique.The part of the internal stator 57 is coated in the vicinity of the inlet 12 of the HP stream 6 with a coating 29 of low thermal conductivity. Likewise, the part of the internal stator 57 in the vicinity of the inlet 18 of the vein MP 8 is provided with a coating 29 with low thermal conductivity.

Dans la réalisation particulière représentée aux figures 3 à 6, le stator interne 57 au voisinage des moyens de protection thermique 10 comporte des bossages 30. Des canalisations 31, 32 latérales et une canalisation radiale 33 sont ménagées dans chaque bossage (voir fig.4).In the particular embodiment shown in Figures 3 to 6, the internal stator 57 in the vicinity of the thermal protection means 10 includes bosses 30. Lateral pipes 31, 32 and a radial pipe 33 are provided in each boss (see fig.4) .

Les canalisations 31, 32, 33 sont alimentées par une prise 34 située dans la veine HP 6 et débouchent dans l'espace interstatorique 19 au voisinage des moyens de protection thermique 10.The pipes 31, 32, 33 are supplied by a socket 34 located in the HP stream 6 and open into the interstatoric space 19 in the vicinity of the thermal protection means 10.

Les bossages 30 sont symétriques par rapport à l'axe de la turbine.The bosses 30 are symmetrical with respect to the axis of the turbine.

Les moyens de positionnement axial 11 sont constitués d'une première partie 35 solidaire du stator interne 57, reposant sur une partie 36 solidaire du stator externe 9 entre un appui 37 et un contre-appui 38.The axial positioning means 11 consist of a first part 35 secured to the internal stator 57, resting on a part 36 secured to the external stator 9 between a support 37 and a counter-support 38.

Des rainures 39 ont été ménagées dans la partie 35 et débouchent dans une cavité 40 de la partie 36. Une cheminée 41 débouchant dans la cavité 40 est ménagée dans le stator externe 9. Chaque cheminée 41 est munie d'une tuyauterie plongeante 42 servant à évacuer la vapeur vers le dispositif de réglage de débit 27 (figure 2). Ces tuyauteries 42 protègent le stator externe 9 d'une trop grande convection.Grooves 39 have been made in the part 35 and open into a cavity 40 of the part 36. A chimney 41 opening into the cavity 40 is formed in the external stator 9. Each chimney 41 is provided with a plunging pipe 42 serving to evacuate the steam to the flow control device 27 (figure 2). These pipes 42 protect the external stator 9 from too much convection.

De préférence on dispose quatre cavités 40 avec leurs tuyauteries 42 réparties régulièrement autour de l'axe de la turbine. Chacune de ces tuyauteries 42 évacue la vapeur vers un dispositif d'adaptation de débit 27. En réglant chacun des dispositifs d'adaptation 27, on peut régler le refroidissement en azimut dans l'espace interstatorique 19.Preferably, there are four cavities 40 with their pipes 42 distributed regularly around the axis of the turbine. Each of these pipes 42 evacuates the steam to a flow adaptation device 27. By adjusting each of the adaptation devices 27, it is possible to adjust the cooling in azimuth in the interstatoric space 19.

Claims (6)

  1. An HP-MP steam turbine body comprising a rotor (1) having an HP portion (2) and an MP portion (3) interconnected by an intermediate portion (4);
    - an HP internal stator to define in conjunction with the HP portion (2) of the rotor an HP stream (6);
    - an MP internal stator to define in conjunction with the MP portion (3) of the rotor an MP stream (8);
    - the HP internal stator and the MP internal stator being positioned axially inside an external stator (9) by sealed axial positioning means (11) situated around the MP stream (8) in a plane which is at a distance from the inlet (18) of said MP stream (8); thermal protection means (10) being situated around the HP stream (6) in a plane at a distance from the inlet (12) of said HP stream (6), said positioning means (11) and said thermal protection means (10) defining in conjunction with the external stator (9) and with the HP and MP internal stators an inter-stator space (19) swept by steam;
    - HP admission means (13) opening out to the inlet (12) of the HP stream (6);
    - MP admission means (17) opening out to the inlet (18) of the MP stream (8) and fed with a flow of steam tapped at the outlet (14) of the HP stream (6) and passed through a resuperheater device (16);
    - the inlets (12, 18) of the HP and MP streams (6, 8) being adjacent to each other and separated by sealing means (20, 21) supported by the internal stators and disposed in the intermediate portion (4) of the rotor (1) between the HP and MP portions (2, 3);
    the turbine body being characterized in that the HP internal stator and the MP internal stator constitute a single internal stator (57), and in that the inter-stator space (19) includes on the one hand steam admission means (24) fed with steam tapped at one of the last stages (25) of the HP stream (6) and opening out in the vicinity of the thermal protection means (10) which isolate the inter-stator space (19) from the outlet (14), and on the other hand steam exhaust means (26, 28) whose orifices are disposed in the vicinity of the axial positioning means (11), the said exhaust means (26, 28) being provided with flow adjustment means (27).
  2. A turbine body according to claim 1, characterized in that the exhaust means (26, 28) are connected to the inlet of the resuperheater device (16) feeding the MP stream (8).
  3. A turbine body according to claim 1 or 2, characterized in that the exhaust means (26, 28) comprise a plurality of exhausts (26) disposed symmetrically about the axis of the turbine, each connected to a respective flow adjustment device (27) enabling the cooling of the interstator space (19) to be adjusted in azimuth.
  4. A turbine body according to any preceding claim, characterized in that at least a portion of the surface of the internal stator (57) facing the intermediate space (4) of the rotor between the HP and MP streams (6, 8) is provided with a coating (29) of low thermal conductivity.
  5. A turbine body according to any preceding claim, characterized in that the steam tapping means (24) delivering said steam into the inter-stator space (19) are constituted by ducts (31, 32, 33) provided through bosses (30) on the internal stator (57) and disposed symmetrically about the axis of the turbine.
  6. A turbine body according to any preceding claim, characterized in that the means (26) for exhausting steam from the inter-stator space (19) comprise grooves (39) provided in the portion (35) of the axial positioning means (11) which are fixed to the internal stator (57) and opening out into cavities (40) provided in the portion (36) of the axial positioning means (11) which are fixed to the external stator (9), flues (41) passing through the external stator (9) and opening out into said cavities (40), said flues being provided with dipping pipework (42) connected to the inlet of the resuperheater device (16).
EP90107617A 1989-04-26 1990-04-23 One piece internal casing for a hp-mp steamturbine with controlled cooling Expired - Lifetime EP0394894B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8905543 1989-04-26
FR8905543A FR2646466B1 (en) 1989-04-26 1989-04-26 INTERNAL STATOR HP-MP SINGLE STEAM TURBINE WITH CONTROLLED AIR CONDITIONING

Publications (2)

Publication Number Publication Date
EP0394894A1 EP0394894A1 (en) 1990-10-31
EP0394894B1 true EP0394894B1 (en) 1993-03-03

Family

ID=9381157

Family Applications (1)

Application Number Title Priority Date Filing Date
EP90107617A Expired - Lifetime EP0394894B1 (en) 1989-04-26 1990-04-23 One piece internal casing for a hp-mp steamturbine with controlled cooling

Country Status (17)

Country Link
US (1) US5149247A (en)
EP (1) EP0394894B1 (en)
JP (1) JPH02301604A (en)
KR (1) KR900016587A (en)
CN (1) CN1023505C (en)
AT (1) ATE86359T1 (en)
AU (1) AU634767B2 (en)
BR (1) BR9001921A (en)
CA (1) CA2015261A1 (en)
CS (1) CS210690A3 (en)
DE (1) DE69000984T2 (en)
DK (1) DK0394894T3 (en)
ES (1) ES2039985T3 (en)
FR (1) FR2646466B1 (en)
MX (1) MX172511B (en)
RU (1) RU1831578C (en)
ZA (1) ZA903191B (en)

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Also Published As

Publication number Publication date
EP0394894A1 (en) 1990-10-31
CN1023505C (en) 1994-01-12
ES2039985T3 (en) 1993-10-01
DE69000984D1 (en) 1993-04-08
RU1831578C (en) 1993-07-30
FR2646466A1 (en) 1990-11-02
AU634767B2 (en) 1993-03-04
MX172511B (en) 1993-12-17
ZA903191B (en) 1991-01-30
BR9001921A (en) 1991-07-30
ATE86359T1 (en) 1993-03-15
DE69000984T2 (en) 1993-06-09
US5149247A (en) 1992-09-22
AU5383090A (en) 1990-11-01
KR900016587A (en) 1990-11-13
CA2015261A1 (en) 1990-10-26
CS210690A3 (en) 1992-02-19
JPH02301604A (en) 1990-12-13
CN1047552A (en) 1990-12-05
DK0394894T3 (en) 1993-06-14
FR2646466B1 (en) 1991-07-05

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