EP0110757B1 - Dispositif de suspension d'aubes statoriques de compresseur axial pour le contrôle actif des jeux entre rotor et stator - Google Patents

Dispositif de suspension d'aubes statoriques de compresseur axial pour le contrôle actif des jeux entre rotor et stator Download PDF

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Publication number
EP0110757B1
EP0110757B1 EP83402151A EP83402151A EP0110757B1 EP 0110757 B1 EP0110757 B1 EP 0110757B1 EP 83402151 A EP83402151 A EP 83402151A EP 83402151 A EP83402151 A EP 83402151A EP 0110757 B1 EP0110757 B1 EP 0110757B1
Authority
EP
European Patent Office
Prior art keywords
envelope
stator
grooves
upstream
axial flow
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.)
Expired
Application number
EP83402151A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0110757A1 (fr
Inventor
Jean-Pierre "Domaine du Château des Dames" Ruis
Marcel Robert Soligny
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Safran Aircraft Engines SAS
Original Assignee
Societe Nationale dEtude et de Construction de Moteurs dAviation SNECMA
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Societe Nationale dEtude et de Construction de Moteurs dAviation SNECMA filed Critical Societe Nationale dEtude et de Construction de Moteurs dAviation SNECMA
Publication of EP0110757A1 publication Critical patent/EP0110757A1/fr
Application granted granted Critical
Publication of EP0110757B1 publication Critical patent/EP0110757B1/fr
Expired legal-status Critical Current

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Classifications

    • 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
    • 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
    • F01D11/14—Adjusting or regulating tip-clearance, i.e. distance between rotor-blade tips and stator casing
    • F01D11/20—Actively adjusting tip-clearance
    • F01D11/24—Actively adjusting tip-clearance by selectively cooling-heating stator or rotor components
    • 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
    • F01D9/02—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles
    • F01D9/04—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector
    • F01D9/041—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector using blades
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/40—Casings; Connections of working fluid
    • F04D29/52—Casings; Connections of working fluid for axial pumps
    • F04D29/54—Fluid-guiding means, e.g. diffusers
    • F04D29/541—Specially adapted for elastic fluid pumps
    • F04D29/542—Bladed diffusers

Definitions

  • the invention relates to an axial flow compressor suitable for active control of the play between rotor and stator, comprising a stator assembly, the blades of which are fixed to an inner casing formed of at least one cylindrical ferrule held by means of fixing to the wall. internal of an outer casing, the space between the two casings being traversed by air taken from a compressor stage.
  • stator vanes are mounted on an inner envelope, made of a material preferably having a low coefficient of expansion, which is suspended from the 'outer casing by fixing means.
  • the control of the heat exchange of the interior envelope with the exterior envelope is obtained by ventilation of the exterior envelope and the space between the two envelopes.
  • the control of the heat exchange of the interior envelope with the exterior envelope is obtained by ventilation of the exterior envelope and the space between the two envelopes.
  • British patent 2,019,954 describes a compressor casing comprising an outer casing and an inner casing, annular, coaxial.
  • the inner casing bears, radially inward, the stator vanes, and outwardly of the pins.
  • the pins cooperate with housings provided in the outer casing.
  • the inner envelope is formed by annular ferrules placed one behind the other along the longitudinal axis of the outer envelope.
  • the nipples and the thickening of the area surrounding their housings form thermal bridges making it possible to control the thermal expansion or contraction of the internal envelope in the radial direction.
  • FR A-2 421 279 relates to a gas turbine and describes a fin support divided into segments which are suspended by means of annular spouts in housings of an outer casing. These segments include cooling channels supplied by radial orifices.
  • GB-A 1 501 916 shows an internal casing of a turbomachine connected to an external casing and comprising circumferential radial grooves in which friction bands and the ends of stator vanes are placed alternately.
  • stator vanes as well as the friction bands ensuring the sealing of the ends of the blades of the rotor vanes are fixed to the inner casing of which they form a non-negligible portion. It is therefore relatively difficult to intervene on the stator to replace damaged blades or friction bands.
  • the purpose of the device according to the invention is to allow effective control of the compressor clearances by protecting the external envelope from the thermal radiation of the compressed air stream, but also to allow an easy change of the blades and the friction bands.
  • the axial flow compressor according to the invention is characterized in that the inner casing is formed of at least one set of hollow cylindrical sectors carrying alternately on their internal faces radial circumferential grooves for the stator vanes and the bands friction and in that said sectors have in projection on a horizontal plane a shape of parallelogram and each sector bears on its external face and in two radial planes two upstream legs and two downstream legs, at least one upstream leg and one downstream leg being axially aligned with each other and with two cooperating legs of the outer casing to receive a fixing pin so that one pin in two crosses the legs of two consecutive sectors.
  • FIG. 1 represents an axial half-section of a compression section or of an axial compressor, more particularly intended to equip a turbomachine.
  • the first three compression stages are arranged in an annular frustoconical channel, the widest part of which receives the air flow to be compressed.
  • the following compression stages are in a substantially cylindrical annular channel.
  • the compressor housing has two envelopes: an inner envelope 1 and an outer envelope 2.
  • the inner envelope fixed on the outer envelope carries the stator vanes and between the crowns of blades, friction bands made of abradable material and on which the ends of the blades of the rotor blades are likely to rub.
  • the stator vanes carry means at the free end of their blades ensuring sealing with the rotor. These means conventionally consist of a friction band 3 on which the lips 4 rubbing carried by the rotor casing rub and located between two rotor disks 5.
  • the rotor discs 5 have in their rims a groove 6 in which the rotor vanes 7 are retained.
  • the upstream section 8 of the compressor is separated from the downstream section 9 by a sampling zone 10 which is in communication with the space 11 formed between the internal and external envelopes and with air intakes 12 intended to supply the compressed air necessary for services and cooling systems for hot parts of the engine, such as the turbine.
  • ventilation ramps 13, four in number according to the example shown are arranged on sections of the outer casing and have the function of ventilating, by rows of orifices, the surface of the casing.
  • Means for controlling the admission of air into the ramps make it possible to control the temperature of the envelope and consequently its dimensional variations. This maintains the constancy of the clearances despite the different thermal inertias between the rotor discs and the compressor casing on which the stator vanes are fixed.
  • the outer envelope 2 consists of three cylindrical sections: an upstream section 14 and a downstream section 15, substantially symmetrical with respect to an intermediate section 16.
  • the sections 14 and 15 consist of a cylindrical shell 17 comprising at one end an external radial flange 18 and an internal radial flange 19.
  • the internal radial flange 19 is notched at regular intervals so as to leave tabs 20 comprising a bore cylindrical 21. These lugs will serve to hold lugs corresponding to 22 provided on the inner casing.
  • the intermediate section 16 is formed of a cylindrical shell whose upstream and downstream edges are welded to the edges of the sections 14 and 15, for example, by electron bombardment. Connections are provided on the outer surface of the shell to constitute the air intakes 12.
  • the ferrule also has near each end a radial flange 23 directed inward and indented to form tabs 24 portsnt in their center a bore.
  • a radial flange 23 directed inward and indented to form tabs 24 portsnt in their center a bore.
  • the external flanges 18 are used for fixing the flanges 25 and 26 ensuring the seal between the external and internal envelopes, as well as possibly for blocking the fixing means 27, pins or tie rods passing through the lugs 20 and 24.
  • the inner envelope is formed of two sets of sectors, an upstream assembly 28 and a downstream assembly 29.
  • Figures 3 and 5 show a hollow cylindrical sector 30 whose projection on a horizontal plane (plane of Figure 2) is a parallelogram .
  • the sectors are arranged so that two of their parallel sides are in the radial planes.
  • the sectors of the downstream assembly 29 comprise on the internal face seven radial grooves (FIGS. 1 and 2), four grooves 31 intended to receive the friction bands 32 and three grooves 33 receiving the stator vanes 34, the friction bands and the blades successively alternating.
  • the sectors bear on their outer face the fixing lugs 22 intended to cooperate with the corresponding fixing lugs provided inside the outer casing.
  • the pins of the outer casing are fixed with those of the inner casing by the pins 27. Because the lateral edges of the sectors are not parallel to the axis of the compressor, it is expected that a spindle fixing 27 on two is fixed to two consecutive sectors.
  • the lateral edges 35 (FIG. 3) of the sectors carry inside and outside a groove intended to receive a bar 36 which ensures the radial seal between two consecutive sectors,
  • the holes 21 provided in the tabs 20 of the outer casing receiving the pins are cylindrical, the holes provided in the tabs 22 of the sector edge are oblong and the others are cylindrical.
  • the grooves 31 receiving the friction bands have a T-shaped section whose leg is directed towards the axis of the compressor .
  • the grooves 33 receiving the blades have a U-shaped section, the edges of the groove having a recess.
  • the recesses of the groove 33 are machined in the edges of the groove 31.
  • the friction bands 32 are fixed on supports 37 made up of two U-shaped rings 38 brazed symmetrically on a segment 39 of a cylindrical shell.
  • the friction bands, metallic or organic, are glued or brazed to the internal surface of the ring segment 39.
  • the stator vanes 34 are assembled into sectors 40 formed by two sections of annular ferrules 41, 42 carrying cutouts corresponding to the profile of the vanes and in which they are brazed or glued at their ends.
  • the portion of the ferrule section 42 directed towards the axis carries the friction band 3 cooperating with the lips 4 of the rotor housing.
  • the ferrule section 41 is produced in the form of a box having on its peripheral edges two longitudinal tabs 43, 44, shaped so as to be able to be placed in the recesses of the groove 33
  • the edges of the ferrules 39 forming the support for the friction strips cover the recesses of the grooves 33 by providing grooves in which the sectors of the stator vanes can be slid and held.
  • the section of the ferrule 42 shown in perspective in FIG. 4, has a width greater than that of the ferrule 44 in order to achieve the continuity of the annular channel in which the compressed air stream flows below the sampling area 10 'air.
  • this one is doubled internally with a thermal insulator 45.
  • This insulator contributes to reduce the transmissions by radiation of the interior envelope towards the external envelope 14-15-18 .
  • the compressor stator is assembled as follows: the friction band supports are slid into the grooves of each sector, then when all the sectors of an assembly are thus equipped, the sectors of the stator vanes are placed.
  • the compressor rotor is covered with the sectors previously prepared and the crown thus reconstituted is positioned by a tool assembly.
  • the ferrules constituting the outer envelope are then presented so that the tabs that they carry are angularly offset with respect to those of the sectors.
  • the upstream and downstream sections of the outer casing are engaged axially and the tab holes are brought back in front of the tab holes of the sectors forming the inner casing, the pins 27 are slid and locked in place by fixing the flanges d 25, 26.
  • the outer casing 14-15-16 is insulated by the thermal insulation 45 on the one hand and, on the other hand, ventilated by the circulation of air in the space between the two envelopes, and that its temperature, therefore its dimensional variations can therefore be controlled by admitting stator air to the outer casing can therefore be controlled and consequently, the clearance between the ends of the rotor blades and the friction strips 32 can be reduced to a minimum and remain almost constant during the transistor operations.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Rotary Pumps (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
EP83402151A 1982-11-08 1983-11-07 Dispositif de suspension d'aubes statoriques de compresseur axial pour le contrôle actif des jeux entre rotor et stator Expired EP0110757B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8218651 1982-11-08
FR8218651A FR2535795B1 (fr) 1982-11-08 1982-11-08 Dispositif de suspension d'aubes statoriques de compresseur axial pour le controle actif des jeux entre rotor et stator

Publications (2)

Publication Number Publication Date
EP0110757A1 EP0110757A1 (fr) 1984-06-13
EP0110757B1 true EP0110757B1 (fr) 1986-09-03

Family

ID=9278972

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83402151A Expired EP0110757B1 (fr) 1982-11-08 1983-11-07 Dispositif de suspension d'aubes statoriques de compresseur axial pour le contrôle actif des jeux entre rotor et stator

Country Status (5)

Country Link
US (1) US4543039A (enrdf_load_stackoverflow)
EP (1) EP0110757B1 (enrdf_load_stackoverflow)
JP (1) JPS59113299A (enrdf_load_stackoverflow)
DE (1) DE3365894D1 (enrdf_load_stackoverflow)
FR (1) FR2535795B1 (enrdf_load_stackoverflow)

Families Citing this family (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2577282B1 (fr) * 1985-02-13 1987-04-17 Snecma Carter de turbomachine associe a un dispositif pour ajuster le jeu entre rotor et stator
FR2591674B1 (fr) * 1985-12-18 1988-02-19 Snecma Dispositif de reglage des jeux radiaux entre rotor et stator d'un compresseur
FR2607198B1 (fr) * 1986-11-26 1990-05-04 Snecma Carter de compresseur adapte pour le pilotage actif de ses dilatations et son procede de fabrication
US4889470A (en) * 1988-08-01 1989-12-26 Westinghouse Electric Corp. Compressor diaphragm assembly
FR2640687B1 (fr) * 1988-12-21 1991-02-08 Snecma Carter de compresseur de turbomachine a pilotage de son diametre interne
GB2236809B (en) * 1989-09-22 1994-03-16 Rolls Royce Plc Improvements in or relating to gas turbine engines
FR2653171B1 (fr) * 1989-10-18 1991-12-27 Snecma Carter de compresseur de turbomachine muni d'un dispositif de pilotage de son diametre interne.
US5197281A (en) * 1990-04-03 1993-03-30 General Electric Company Interstage seal arrangement for airfoil stages of turbine engine counterrotating rotors
KR100204743B1 (ko) * 1990-09-12 1999-06-15 레비스 스테픈 이 압축기 케이스의 구조체 및 외부케이스 조립방법
US5127794A (en) * 1990-09-12 1992-07-07 United Technologies Corporation Compressor case with controlled thermal environment
US5299910A (en) * 1992-01-23 1994-04-05 General Electric Company Full-round compressor casing assembly in a gas turbine engine
US5351478A (en) * 1992-05-29 1994-10-04 General Electric Company Compressor casing assembly
US5462403A (en) * 1994-03-21 1995-10-31 United Technologies Corporation Compressor stator vane assembly
US5562408A (en) * 1995-06-06 1996-10-08 General Electric Company Isolated turbine shroud
US6553665B2 (en) * 2000-03-08 2003-04-29 General Electric Company Stator vane assembly for a turbine and method for forming the assembly
US6926496B2 (en) * 2002-12-31 2005-08-09 General Electric Company High temperature turbine nozzle for temperature reduction by optical reflection and process for manufacturing
US20070237629A1 (en) * 2006-04-05 2007-10-11 General Electric Company Gas turbine compressor casing flowpath rings
EP2075416B1 (fr) * 2007-12-27 2011-05-18 Techspace Aero Procédé de fabrication d'un élément de turbomachine et dispositif ainsi obtenu
WO2009123302A2 (en) * 2008-03-31 2009-10-08 Mitsubishi Heavy Industries, Ltd. Thermal insulation structure for structural member, and scroll structure
EP2236761A1 (de) * 2009-04-02 2010-10-06 Siemens Aktiengesellschaft Leitschaufelträger
JP4916560B2 (ja) * 2010-03-26 2012-04-11 川崎重工業株式会社 ガスタービンエンジンの圧縮機
US9366149B2 (en) 2012-09-21 2016-06-14 United Technologies Corporation Multi-stage high pressure compressor case
US12270345B2 (en) * 2022-06-09 2025-04-08 Pratt & Whitney Canada Corp. Containment assembly for an aircraft engine

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Publication number Priority date Publication date Assignee Title
US2917276A (en) * 1955-02-28 1959-12-15 Orenda Engines Ltd Segmented stator ring assembly
US3000552A (en) * 1957-05-28 1961-09-19 Gen Motors Corp Compressor vane mounting
US2997275A (en) * 1959-03-23 1961-08-22 Westinghouse Electric Corp Stator structure for axial-flow fluid machine
US2980396A (en) * 1959-06-29 1961-04-18 Gen Electric Stator construction for turbine engines
US3849023A (en) * 1973-06-28 1974-11-19 Gen Electric Stator assembly
JPS5035364U (enrdf_load_stackoverflow) * 1973-07-25 1975-04-15
US3864056A (en) * 1973-07-27 1975-02-04 Westinghouse Electric Corp Cooled turbine blade ring assembly
GB1501916A (en) * 1975-06-20 1978-02-22 Rolls Royce Matching thermal expansions of components of turbo-machines
US4083180A (en) * 1976-10-01 1978-04-11 Caterpillar Tractor Co. Gas turbine engine internal insulation
CH633346A5 (de) * 1978-03-29 1982-11-30 Bbc Brown Boveri & Cie Leitschaufeltraeger an einer gasturbine.
GB2019954B (en) * 1978-04-04 1982-08-04 Rolls Royce Turbomachine housing
FR2452600A1 (fr) * 1979-03-28 1980-10-24 United Technologies Corp Moteur a turbine a gaz avec un carter de compresseur divise longitudinalement et comportant des collecteurs s'etendant circonferentiellement autour du carter
US4329114A (en) * 1979-07-25 1982-05-11 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Active clearance control system for a turbomachine
GB2076071B (en) * 1980-05-16 1983-11-02 United Technologies Corp Flow directing assembly for a gas turbine engine
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US4431373A (en) * 1980-05-16 1984-02-14 United Technologies Corporation Flow directing assembly for a gas turbine engine

Also Published As

Publication number Publication date
FR2535795B1 (fr) 1987-04-10
FR2535795A1 (fr) 1984-05-11
JPH0158359B2 (enrdf_load_stackoverflow) 1989-12-11
JPS59113299A (ja) 1984-06-29
DE3365894D1 (en) 1986-10-09
EP0110757A1 (fr) 1984-06-13
US4543039A (en) 1985-09-24

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