EP1520957A1 - Dispositif et procédé pour amortir les vibrations entre des aubes turbocompresseur et le boítier d'une turbine à gaz - Google Patents

Dispositif et procédé pour amortir les vibrations entre des aubes turbocompresseur et le boítier d'une turbine à gaz Download PDF

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Publication number
EP1520957A1
EP1520957A1 EP03256262A EP03256262A EP1520957A1 EP 1520957 A1 EP1520957 A1 EP 1520957A1 EP 03256262 A EP03256262 A EP 03256262A EP 03256262 A EP03256262 A EP 03256262A EP 1520957 A1 EP1520957 A1 EP 1520957A1
Authority
EP
European Patent Office
Prior art keywords
casing
stator vane
outer platform
gas turbine
attached
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP03256262A
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German (de)
English (en)
Other versions
EP1520957B1 (fr
Inventor
Carl Grant
David Curr Douglas
Stephen Rex Payling
James Vota
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.)
General Electric Co
Original Assignee
General Electric Co
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Filing date
Publication date
Application filed by General Electric Co filed Critical General Electric Co
Priority to EP20030256262 priority Critical patent/EP1520957B1/fr
Priority to DE2003618852 priority patent/DE60318852T2/de
Publication of EP1520957A1 publication Critical patent/EP1520957A1/fr
Application granted granted Critical
Publication of EP1520957B1 publication Critical patent/EP1520957B1/fr
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01DNON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D25/00Component parts, details, or accessories, not provided for in, or of interest apart from, other groups
    • F01D25/24Casings; Casing parts, e.g. diaphragms, casing fastenings
    • F01D25/246Fastening of diaphragms or stator-rings
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01DNON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/12Blades
    • F01D5/26Antivibration means not restricted to blade form or construction or to blade-to-blade connections or to the use of particular materials
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01DNON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D9/00Stators
    • F01D9/02Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles
    • F01D9/04Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector
    • F01D9/041Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector using blades
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01DNON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D9/00Stators
    • F01D9/02Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles
    • F01D9/04Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector
    • F01D9/042Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector fixing blades to stators

Definitions

  • the present invention relates generally to stator vanes in compressors of a gas turbine engine and, in particular, to the damping of vibrations transmitted to such stator vanes from the case of the engine.
  • stator vanes for the low pressure compressor and/or the high pressure compressor of the engine are generally attached to the engine case. This may be accomplished, for example, by sliding the stator vanes into rails supplied on the inner surface of the case or by capturing a flange between a split-line in the case. In both instances, at least some of the vibration energy of the engine case is transmitted to the stator vanes. Since the individual stator vanes and/or the shroud systems for such stator vanes can vibrate at frequency modes which are substantially synchronous with the case modes, the potential for wear damage and/or high cycle fatigue damage is created.
  • stator vane assembly it would be desirable for a stator vane assembly to be developed which damps the vibrations from the engine case to the stator vanes of the compressor. It is also desirable for the stator vane assembly to be easily assembled and disassembled to facilitate manufacturing and repair.
  • a stator vane assembly for a compressor of a gas turbine engine including a stator vane having an inner portion and an outer portion, a platform attached to the outer portion of the stator vane, a casing for the gas turbine engine, wherein the outer platform of the stator vane is attached to the casing in a manner so that an open area is defined therebetween, and a member positioned within the defined open area for damping vibrations transmitted from the casing to the outer platform.
  • a stator vane assembly for a compressor of a gas turbine engine, wherein the gas turbine engine includes a split-line casing having first and second circumferential flanges surrounding the compressor.
  • the stator vane assembly includes a stator vane having an inner portion and an outer portion, an outer platform attached to the outer portion of the stator vane, a flange extending from the outer platform which is positioned between and attached to the first and second circumferential flanges of the split-line casing so that an open area is defined between the stator vane outer platform and the casing, and a member positioned within the defined open area of the casing for damping vibrations transmitted from the casing to the outer platform.
  • a stator vane assembly for a compressor of a gas turbine engine where the gas turbine engine includes a casing surrounding the compressor having a plurality of rail members positioned along an inner surface thereof.
  • the stator vane assembly includes a stator vane having an inner portion and an outer portion, an outer platform attached to the outer portion of the stator vane, a pair of end members extending from the outer platform which are positioned within and attached to the rail member of the casing so that an open area is defined between the stator vane outer platform and the casing, and a member positioned within the defined open area for damping vibrations transmitted from the casing to the outer platform.
  • a method of damping vibrations from an engine casing to a stator vane of a compressor connected to the casing is disclosed as including the following steps: positioning an outer platform of the stator vane with respect to the casing so as to define an open area therebetween; providing a damping member within the defined open area; and, attaching the outer platform to the casing.
  • the casing may have a split-line configuration so that first and second circumferential flanges are mated together, wherein the outer platform is attached to the casing by means of a flange extending therefrom which is positioned between and connected to the first and second circumferential flanges.
  • the casing may have a clam shell configuration so that first and second axial flanges are mated together, wherein the outer platform is attached to the casing by means of a rail member incorporated into an inner surface of the casing.
  • Fig. 1 depicts an exemplary gas turbine engine identified generally by reference numeral 10.
  • Gas turbine engine 10 is typically utilized in marine and industrial applications, and includes in serial arrangement a low pressure compressor 12, a high pressure compressor 14, a booster compressor 13, a combustor 16, a high pressure turbine 18 and a low pressure turbine 20. It will be seen that a first shaft 22 connects high pressure turbine 18 and high pressure compressor 14 while a second shaft 24 connects low pressure turbine 20 and low pressure compressor 12.
  • a longitudinal axis 25 is provided in Fig. 1 for reference purposes.
  • gas turbine engine 10 includes a casing 26 which has a split-line configuration at an axial position adjacent high pressure compressor 14. This is evident from a first circumferential flange 28 and a second circumferential flange 30 being connected in abutting relation with a plurality of circumferentially spaced pins 32 or other similar devices connecting such flanges. It will be noted that a particular stage of stator vanes for high pressure compressor 14 (one stator vane 34 being shown) is positioned immediately downstream of the split-line in casing 26. Due to its proximity to flanges 28 and 30, stator vanes 34 may be more susceptible to the vibrations of casing 26.
  • a damping member 36 is preferably positioned within an area 38 defined between an outer portion 40 of each stator vane 34 and casing 26.
  • each stator vane 34 is retained within a bushing 44 located in a shroud 45, as is known in the art.
  • Outer portion 40 of each stator vane 34 is attached to a platform 47 which is retained by casing 26, where outer platform 47 preferably includes a first or downstream end 46 having a substantially L-shaped design which is sized to fit within a corresponding slot 48 in casing 26.
  • a second or upstream end 50 of each outer platform 47 preferably is a flange which is configured and sized so as to be inserted between first and second circumferential flanges 28 and 30, respectively, of casing 26 in abutting relation.
  • Each flange 50 also includes at least one opening therethrough so as to permit one or more pins 32 to be inserted therethrough.
  • Each outer platform 47 further includes a middle section 52 connecting upstream end 50 and downstream end 46, where middle section 52 extends substantially parallel to casing 26. Because of the respective configurations for each outer platform 47 and casing 26, it will be appreciated that individual open areas 38 are defined therebetween. In order to dampen vibrations experienced by each outer platform 47 (and therefore each stator vane outer portion 40) from casing 26, a damping member 36 is preferably located within each defined open area 38.
  • Damping member 36 is preferably constructed of an elastomeric material which preferably is preformed and cured prior to placement within each defined area 38. It will be appreciated that each damping member 36 may be sized to extend within only a portion of each defined area 38 (see Fig. 3) or within substantially all of defined area 38 (see Fig. 4). It will be understood that the elastomeric material will preferably meet certain predefined parameters, including the ability to retain its properties under high temperatures. In particular, the elastomeric material of each damping member 36 will preferably retain its properties in temperatures of at least approximately 300°F, more preferably in temperatures of at least approximately 375°F, and optimally in temperatures of at least approximately 450°F.
  • damping member 36 is able to provide similar functionality to stator vanes and their platforms positioned within the temperature environments of low compressor 12 and/or booster compressor 13.
  • damping member 36 When positioning damping member 36 within a defined area 38, it is preferred that a layer of adhesive 54 be applied thereto so as to maintain it in position while each stator vane 34 and its platform 47 is connected to casing 26. It will be appreciated that adhesive layer 54 may dissolve or burn off once gas turbine engine 10 is in operation, whereby damping member 36 will be either frictionally engaged in defined area 38 or permitted to float therein.
  • damping member 36 in a preformed and cured state is shown to be substantially rectangular in shape, although any shape and size may be utilized provided it performs the desired damping function between casing 26 and stator vanes 34.
  • a plurality of grooves 56 is preferably formed in damping member 36 in order to provide better flexibility and assembly (see Fig. 7). Orientation of damping member 36 and grooves 56 within each defined area 38, however, is not deemed to be limiting upon the present invention.
  • FIG. 5 and 6 An alternate configuration for the stator vane assembly is depicted in Figs. 5 and 6, where a casing 58 thereof is continuous in an axial direction but has a pair of flanges 60 and 62 which are connected in a clam shell design at opposite radial ends (only one of which is shown).
  • This casing configuration further provides a plurality of spaced rail members 64 along an inner surface thereof into which a plurality of stator vanes 66 are inserted and retained prior to assembly of casing 58.
  • an open area 68 is accordingly defined between casing 58 and an outer platform 70 for each stator vane 66.
  • Each outer platform 70 further includes a pair of end members 71 and 73 which are received within corresponding pockets 75 and 77 of rail member 64.
  • a damping member 72 like that discussed above is preferably positioned within each defined area 68 so as to damp the vibrations experienced by outer platforms 70 and stator vanes 66 from casing 58.
  • damping member 72 will preferably be of a size and shape so as to fit within open area 68 and perform its intended function.
  • elastomeric material may alternatively be squeezed into such areas 68, or "in situ,” where it is able to cure in place and perform as damping member 72.
  • damping members 72 are able to be more closely sized to open areas 68. This method may also be utilized with split-line casing 26, as seen in Fig. 4.
  • damping members 36 and 72 preferably reduce the vibrations experienced by outer platforms 47 and 70 from casings 26 and 58, respectively, by at least approximately 10%. More preferably, damping members 36 and 72 are able to damp the vibrations from casings 26 and 58 by at least approximately 20% and optimally by at least approximately 30%.
  • a method of damping vibrations from casing 26 to stator vanes 34 includes the steps of positioning outer platforms 47 of stator vanes 34 with respect to casing 26 so as to define an open area 38 therebetween, providing damping member 36 made of an elastomeric material within such defined open areas 38 of casing 26, and securing damping members 36 therein. Thereafter, stator vanes 34 are attached to casing 26 so that outer platforms 47 are retained adjacent to damping members 36 and vibrations from casing 26 are dampened. Prior to such steps, damping members 36 are preferably preformed and cured, including grooves 56 formed therein, and adhesive layer 54 applied to a surface thereof. Outer platforms 47 are attached to casing 26 and maintained in position by means of flanges 50 which extend therefrom and are positioned between opposite flanges 28 and 30 of casing 26.
  • stator vane assembly and damping member 36 thereof can be accomplished by appropriate modifications by one of ordinary skill in the art without departing from the scope of the invention.
  • damping member 36 is illustrated as being used in a stator vane of high pressure compressor 14 for gas turbine engine 10, it may be utilized with any fixed or stator vane of any compressor.
  • present invention may be utilized with engine casings have other configurations than that disclosed herein.
EP20030256262 2003-10-03 2003-10-03 Dispositif et procédé pour amortir les vibrations entre des aubes turbocompresseur et le boîtier d'une turbine à gaz Expired - Fee Related EP1520957B1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP20030256262 EP1520957B1 (fr) 2003-10-03 2003-10-03 Dispositif et procédé pour amortir les vibrations entre des aubes turbocompresseur et le boîtier d'une turbine à gaz
DE2003618852 DE60318852T2 (de) 2003-10-03 2003-10-03 Apparat und Methode zur Dämpfung von Vibrationen zwischen Kompressorleitschaufeln und dem Gehäuse einer Gasturbine

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP20030256262 EP1520957B1 (fr) 2003-10-03 2003-10-03 Dispositif et procédé pour amortir les vibrations entre des aubes turbocompresseur et le boîtier d'une turbine à gaz

Publications (2)

Publication Number Publication Date
EP1520957A1 true EP1520957A1 (fr) 2005-04-06
EP1520957B1 EP1520957B1 (fr) 2008-01-23

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EP20030256262 Expired - Fee Related EP1520957B1 (fr) 2003-10-03 2003-10-03 Dispositif et procédé pour amortir les vibrations entre des aubes turbocompresseur et le boîtier d'une turbine à gaz

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EP (1) EP1520957B1 (fr)
DE (1) DE60318852T2 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2009242A1 (fr) * 2007-06-26 2008-12-31 Snecma Dispositif amortisseur pour stator de turbomachine
WO2015060982A1 (fr) * 2013-10-25 2015-04-30 Siemens Aktiengesellschaft Bague de support d'aube externe comprenant une plaque arrière solide dans une section compresseur d'une turbine à gaz
WO2015061063A1 (fr) * 2013-10-25 2015-04-30 Siemens Aktiengesellschaft Anneau de support externe d'aube sans crochet avant dans une section de compresseur d'un moteur à turbine à gaz
US9816387B2 (en) 2014-09-09 2017-11-14 United Technologies Corporation Attachment faces for clamped turbine stator of a gas turbine engine
CN107438702A (zh) * 2015-04-02 2017-12-05 西门子股份公司 导叶组件
CN108953130A (zh) * 2018-07-10 2018-12-07 南京航空航天大学 一种压气机静子叶片扇形段快拆机匣装置

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4897021A (en) * 1988-06-02 1990-01-30 United Technologies Corporation Stator vane asssembly for an axial flow rotary machine
US5429479A (en) * 1993-03-03 1995-07-04 Societe Nationale D'etude Et De Construction De Moteurs D'aviation "Snecma" Stage of vanes free at one extremity
US5848874A (en) * 1997-05-13 1998-12-15 United Technologies Corporation Gas turbine stator vane assembly
EP1081335A2 (fr) * 1999-08-09 2001-03-07 United Technologies Corporation Stator pour une turbomachine et méthode pour la fabrication

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4897021A (en) * 1988-06-02 1990-01-30 United Technologies Corporation Stator vane asssembly for an axial flow rotary machine
US5429479A (en) * 1993-03-03 1995-07-04 Societe Nationale D'etude Et De Construction De Moteurs D'aviation "Snecma" Stage of vanes free at one extremity
US5848874A (en) * 1997-05-13 1998-12-15 United Technologies Corporation Gas turbine stator vane assembly
EP1081335A2 (fr) * 1999-08-09 2001-03-07 United Technologies Corporation Stator pour une turbomachine et méthode pour la fabrication

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2009242A1 (fr) * 2007-06-26 2008-12-31 Snecma Dispositif amortisseur pour stator de turbomachine
FR2918108A1 (fr) * 2007-06-26 2009-01-02 Snecma Sa Dispositif amortisseur pour stator de turbomachine
US8147191B2 (en) 2007-06-26 2012-04-03 Snecma Damping device for turbomachine stator
WO2015060982A1 (fr) * 2013-10-25 2015-04-30 Siemens Aktiengesellschaft Bague de support d'aube externe comprenant une plaque arrière solide dans une section compresseur d'une turbine à gaz
WO2015061063A1 (fr) * 2013-10-25 2015-04-30 Siemens Aktiengesellschaft Anneau de support externe d'aube sans crochet avant dans une section de compresseur d'un moteur à turbine à gaz
CN105683511A (zh) * 2013-10-25 2016-06-15 西门子股份公司 燃气涡轮发动机的压缩机部中的包括强背板的外翼片支撑环
JP2016540917A (ja) * 2013-10-25 2016-12-28 シーメンス アクチエンゲゼルシヤフトSiemens Aktiengesellschaft ガスタービンエンジンの圧縮機セクションに強固なバックプレートを備えるアウタベーン支持リング
CN105683511B (zh) * 2013-10-25 2018-12-28 西门子股份公司 燃气涡轮发动机的压缩机部中的包括强背板的外翼片支撑环
US9816387B2 (en) 2014-09-09 2017-11-14 United Technologies Corporation Attachment faces for clamped turbine stator of a gas turbine engine
US11041392B2 (en) 2014-09-09 2021-06-22 Raytheon Technologies Corporation Attachment faces for clamped turbine stator of a gas turbine engine
CN107438702A (zh) * 2015-04-02 2017-12-05 西门子股份公司 导叶组件
CN108953130A (zh) * 2018-07-10 2018-12-07 南京航空航天大学 一种压气机静子叶片扇形段快拆机匣装置

Also Published As

Publication number Publication date
EP1520957B1 (fr) 2008-01-23
DE60318852T2 (de) 2009-02-05
DE60318852D1 (de) 2008-03-13

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