US20110027092A1 - Arrangement for axially securing rotating blades in arotor, and gas turbine having such an arrangement - Google Patents

Arrangement for axially securing rotating blades in arotor, and gas turbine having such an arrangement Download PDF

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Publication number
US20110027092A1
US20110027092A1 US12/594,353 US59435308A US2011027092A1 US 20110027092 A1 US20110027092 A1 US 20110027092A1 US 59435308 A US59435308 A US 59435308A US 2011027092 A1 US2011027092 A1 US 2011027092A1
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US
United States
Prior art keywords
blocking element
recess
rotor
arrangement
slot
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.)
Abandoned
Application number
US12/594,353
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English (en)
Inventor
Darren T. Engle
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.)
Siemens AG
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Siemens AG
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
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Assigned to SIEMENS AKTIENGESELLSCHAFT reassignment SIEMENS AKTIENGESELLSCHAFT ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: ENGLE, DARREN T.
Publication of US20110027092A1 publication Critical patent/US20110027092A1/en
Abandoned legal-status Critical Current

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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
    • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/30—Fixing blades to rotors; Blade roots ; Blade spacers
    • F01D5/3007—Fixing blades to rotors; Blade roots ; Blade spacers of axial insertion type
    • F01D5/3015—Fixing blades to rotors; Blade roots ; Blade spacers of axial insertion type with side plates
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
    • F05B2260/00—Function
    • F05B2260/30—Retaining components in desired mutual position
    • F05B2260/301—Retaining bolts or nuts

Definitions

  • the invention refers to an arrangement for axial locking of rotor blades in a rotor, with a shaft collar, on the outer periphery of which provision is made for rotor blade retaining slots which extend in the axial direction of the rotor and in which rotor blades, with blade roots which correspond to the rotor blade retaining slot, are arranged in each case, with a projection which is arranged on an end-face side surface of the shaft collar in the region of the retaining slots, in which projection a radially outwardly open encompassing slot is provided and with radially inwardly open locking slots which are arranged in each rotor blade and which lie radially opposite the encompassing slot in each case, wherein for axial locking of the rotor blades provision is made for plate-like sealing elements which in each case engage in the encompassing slot and in the locking slot, forming an end-face sealing ring in the circumferential direction, wherein at least one of the sealing elements has a means for securing the sealing elements against displacement in the circumfer
  • Rotors of gas turbines are known in which turbine rotor blades, which are arranged on the outer periphery in rotor blade retaining slots, are secured against axial displacement by means of sealing plates.
  • to fasten these sealing plates on the rotor by means of riveting is known for example from U.S. Pat. No. 3,957,393.
  • FIG. 1 shows a generic-type arrangement in a plan view
  • FIG. 2 shows an arrangement in a cross section according to the line of intersection II-II in FIG. 1 .
  • two slightly overlapping sealing plates 16 are provided as sealing elements which in each case cover by half the end-face opening of the rotor blade retaining slot 12 .
  • Each sealing plate 16 by its radially inner end 18 is inserted in an encompassing slot 20 which is provided on a rotor disk 19 on the end face, and by its radially outer end 22 is inserted in a locking slot 24 which is provided on the underside 26 of a platform 28 of the rotor blade 14 .
  • a rectilinear metal strip 30 which extends essentially in the radial direction of the rotor 23 , is fastened on each sealing plate.
  • Each metal strip 30 terminates at its radially outer end 32 in a uniformly converging point 34 .
  • Chamfered edges 36 are provided on the platforms 28 of the rotor blades 14 , wherein two oppositely disposed edges 36 of directly adjacent turbine rotor blades 14 form in each case a recess 38 which tapers to a point and into which the point 34 of the metal strip 30 can project and abut for securing the sealing plate 16 against displacement in the circumferential direction U.
  • the sealing plates 16 furthermore cater for separation of two regions 37 , 39 in which on the one hand cooling air can enter and on the other hand some of the hot gas can possibly enter.
  • two parallel slots 40 are provided in the last-named, through which the metal strip 30 , which is already pre-bent into a U-shape, is inserted.
  • the end 41 of the metal strip 30 opposite the point 34 is already bent into the position which is shown in FIG. 2 for the fastening of the metal strip 30 .
  • the sealing plates 16 with the pre-installed metal strips 30 are threaded one after the other into the endlessly encompassing slot 20 which is arranged on the rotor disk 19 , and into the locking slot 24 which is arranged on the underside 26 of the platform 28 .
  • the sealing plates 16 are positioned along the circumference of the encompassing slot 20 so that each metal strip 30 lies opposite a recess 38 .
  • the points 34 of the metal strips 30 are then bent into the recesses 38 in order to exclude displacement of the sealing plates 16 in the circumferential direction U.
  • the metal strips may be bent only once on account of the enormously high mechanical requirements, when exchanging a rotor blade in the event of a service the metal strip which is then bent up is to be replaced by a new metal strip. Furthermore, the slots which are provided for accommodating the metal strips in the sealing plates weaken the said sealing plates.
  • the provision of a gas turbine with such an arrangement is a further object of the invention.
  • the invention provides that in the case of the generic-type arrangement the means for securing the sealing elements against displacement in the circumferential direction comprise an opening which is provided in the sealing element and also a recess which is provided in the side surface of the shaft collar and approximately aligns with the opening, and a positionally locked blocking element which is seated in the recess and in the opening.
  • the invention avoids the previous configuration in which a metal strip which is hooked into the sealing element engages in a form-fitting manner in a recess. Instead of the metal strip, a blocking element is now provided which can be inserted into the recess which is provided on the shaft collar on the end face.
  • the blocking element blocks displacement of the sealing element in the circumferential direction since, being arranged in the region of the sealing element, it extends transversely to the encompassing slot in which the sealing element is seated and in the process engages in the opening which is provided on the sealing element.
  • a negligible and tolerable clearance of the sealing element along the encompassing slot is possible only insofar as the width of the opening as seen in the circumferential direction is larger than the width of the blocking element which is to be considered in the circumferential direction.
  • the blocking element By using a blocking element which engages in the opening of the sealing element and is fastened on the end face on the shaft collar by means of caulking which plastically deforms the blocking element, a particularly reliable and simple axial securing of the sealing element against displacement in the circumferential direction can be achieved. Furthermore, installation is to be accomplished quickly and simply.
  • the blocking element is to be plastically deformed on the end face with a suitable caulking tool, for example a tool in the style of a hammer and chisel, so that it abuts in the recess under tension.
  • the blocking element is formed in the shape of a wedge in cross section in the region of the recess and moreover comprises a bolt which projects on the end face and which can be inserted into the opening of the sealing element.
  • a defined position of the blocking element in the rotor is predetermined.
  • the orientation of the wedge shape of the recess is selected so that the converging side walls point outwards, in the same way as the flanks of the blocking element which correspond to them.
  • the wedge-shaped blocking element is braced outwards under centrifugal force action and in the process wedges or jams further in the recess which further increases the frictional engagement between the flanks and the side walls and makes an unwanted loosening of the blocking element more difficult. Consequently, a particularly reliable arrangement can be disclosed as a result of this.
  • the recess which accommodates the blocking element is open as seen in the radially outward direction.
  • the blocking element which is inserted therein can be plastically deformed on the circumferential side, with regard to the rotor, instead of the end-face deformation.
  • a form-fit for positional locking of the blocking element can additionally also be provided in addition to the caulking of the blocking element.
  • the recess extending in the axial direction of the rotor, is arranged in the side surface of the shaft ring in such a way that it extends right into the encompassing slot. Weakening of the shaft collar or of a rotor disk which preferably forms the shaft collar is avoided in this case. Therefore, the opening which is provided on the sealing element is then provided on the radial inner end of the sealing element. This region of the sealing element heats up the least during operation so that the rigidity and the temperature resistance of the sealing element are not impaired as a result of the opening.
  • every other sealing element, or each sealing element has the means for securing the sealing elements against displacement.
  • the arrangement is expediently provided on a rotor of a stationary gas turbine which is exposed to throughflow in the axial direction.
  • FIG. 1 shows the arrangement for axial locking of rotor blades in a rotor according to the prior art
  • FIG. 2 shows the cross-sectional view according to FIG. 1 along the line of intersection II-II
  • FIG. 3 shows the detail of a plan view of a rotor disk with a rotor blade arranged thereupon as an arrangement for axial locking of the rotor blade by means of a sealing element
  • FIG. 4 shows a perspective view of a blocking element according to the invention
  • FIG. 5 shows a perspective view of a blocking element which is inserted into the recess of the rotor according to a second development.
  • FIG. 3 shows a detail of the end-face plan view of the shaft collar 21 , which is formed by a rotor disk 19 , of a rotor 23 of a gas turbine.
  • the rotor 23 which is rotatable around the rotational axis 50 , has rotor blade retaining slots 12 which are distributed on its outer periphery 52 along the circumference U and extend in the axial direction, into which slots a rotor blade 14 , with a blade root 54 which is constructed corresponding to the rotor blade retaining slot 12 , in each case can be inserted.
  • a rotor blade 14 is already inserted in the rotor blade retaining slot 12 which is shown in the middle in FIG. 3 .
  • FIG. 3 shows a detail of the end-face plan view of the shaft collar 21 , which is formed by a rotor disk 19 , of a rotor 23 of a gas turbine.
  • the rotor 23 which is rotatable around the rotational axis 50 , has
  • a projection 58 or widening, with a radially outwardly open encompassing slot 20 therein, which extends in the axial direction, is arranged on an end face of the rotor disk 19 or on an end-face side surface 56 of the shaft collar 21 .
  • the encompassing slot 20 for example is arranged radially further inwards than the rotor blade retaining slots 12 .
  • the rotor blade 14 has a platform 28 which is arranged between blade root 54 and the profiled blade airfoil and on the underside of which provision is made for a locking slot 24 which is open towards the encompassing slot 20 and in this case lies opposite this.
  • a sealing element 42 is inserted into the endlessly encompassing slot 20 and in the locking slot 24 and secures the rotor blade 14 against displacement along the rotor blade retaining slot.
  • the sealing element 42 completely covers the end-face opening of one of the rotor blade slots 12 . In this way, only one of the rotor blades 14 is secured in each case by one of the sealing elements 42 against displacement along the rotor blade retaining slot 12 .
  • sealing elements 42 can be distributed over the circumference so that two directly adjacent sealing elements engage by half in the locking slot 24 of the rotor blade 14 in each case. Then two adjacent sealing elements secure one of the rotor blades 14 against axial displacement.
  • a completely installed ring of sealing elements 42 which slightly overlap in each case, forms a sealing ring which separates a region 37 which is exposed to throughflow by a cooling medium from a further region 39 in which a hot gas can possibly be encountered ( FIG. 2 ).
  • an opening 63 which can be a cutout but also a hole, is provided on the radially inner end 61 of the sealing element 42 .
  • a recess 65 which extends essentially in the axial direction of the rotor 23 , i.e. parallel to its rotational axis 50 , is provided on the side surface 56 of the shaft collar 21 in the region of the projection 58 in each case.
  • Each recess 65 has two oppositely disposed side surfaces 66 which, as seen in the outward direction, extend towards each other in a wedge-like manner, but do not touch, forming a gap.
  • an outwardly closed recess can also be provided.
  • the two side walls 66 which extend towards each other meet in a rounded point.
  • the blocking element 67 which is perspectively shown in FIG. 4 can be inserted into the recess 65 .
  • the blocking element 67 comprises a section with a wedge shape which corresponds to the recess 65 , with flanks 70 which extend towards each other, and a bolt 69 which is arranged on the wedge-shaped section on the end face. With the blocking element 67 inserted in the recess 65 , its bolt 69 engages in the opening 63 of the sealing element 42 .
  • the means for securing the sealing element 42 against displacement in the circumferential direction U comprises the opening 63 in the sealing element 42 , the recess 65 which is arranged in the end face of the rotor disk 19 , and also the blocking element 67 which can be inserted into the recess.
  • a negligible and tolerable clearance of the sealing element 42 along the encompassing slot 20 is possible only insofar as the width of the opening 63 as seen in the circumferential direction is larger than the width or the diameter of the bolt which is to be considered in the circumferential direction.
  • the width of the opening 63 preferably corresponds essentially to the diameter of the bolt 69 .
  • the blocking element 67 After inserting the blocking element 67 in the recess 65 , the blocking element is slightly plastically deformed by means of a caulking process.
  • the blocking element 67 in this case is plastically deformed in the region 71 .
  • the still existing, but negligible, clearance for inserting the blocking element 67 is removed so that a secure seating of the blocking element 67 results.
  • the flanks 70 are pressed onto the sidewalls 66 .
  • a reliable frictional engagement is created between the walls 66 of the recess 65 and the flanks 70 of the blocking element 67 which reliably prevents the unwanted loosening of the blocking element.
  • the caulking process can be carried out by means of a suitable chisel which is slightly rounded at the point, which when placed on the blocking element in the region 71 is provided with a hammer blow.
  • the blocking element has an end-face premachined depression 71 in which the chisel is to be placed.
  • FIG. 5 An alternative development of the invention is shown perspectively in FIG. 5 .
  • the blocking element 67 which is shown from FIG. 4 is inserted in the recess 65 with only a slight alteration.
  • the blocking element 67 which is to be used for FIG. 5 has two depressions 71 on the generated surface side (circumferential side), with regard to the rotor, as an aid for the caulking process and which, providing the blocking element 67 is inserted in the recess 65 according to FIG. 5 , in each case lie opposite a pocket 72 which is provided in the sidewalls 66 on the circumferential side.
  • the material of the blocking element which is adjacent to the depressions 71 can be introduced into the pockets 72 so that a form-fit results for secure positioning of the blocking element 67 in the recess 65 .

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
US12/594,353 2007-04-04 2008-03-19 Arrangement for axially securing rotating blades in arotor, and gas turbine having such an arrangement Abandoned US20110027092A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP07007088A EP1978211A1 (de) 2007-04-04 2007-04-04 Anordnung zur Axialsicherung an Laufschaufeln in einem Rotor sowie Gasturbine mit einer solchen Anordnung
PCT/EP2008/053271 WO2008122492A1 (de) 2007-04-04 2008-03-19 Anordnung zur axialsicherung an laufschaufeln in einem rotor sowie gasturbine mit einer solchen anordnung

Publications (1)

Publication Number Publication Date
US20110027092A1 true US20110027092A1 (en) 2011-02-03

Family

ID=38372409

Family Applications (1)

Application Number Title Priority Date Filing Date
US12/594,353 Abandoned US20110027092A1 (en) 2007-04-04 2008-03-19 Arrangement for axially securing rotating blades in arotor, and gas turbine having such an arrangement

Country Status (6)

Country Link
US (1) US20110027092A1 (ru)
EP (2) EP1978211A1 (ru)
JP (1) JP4942844B2 (ru)
CN (1) CN101680304B (ru)
RU (1) RU2427713C2 (ru)
WO (1) WO2008122492A1 (ru)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20170037736A1 (en) * 2014-04-29 2017-02-09 Siemens Aktiengesellschaft Wheel disk assembly and method for assembling a wheel disk assembly
US9745852B2 (en) 2012-05-08 2017-08-29 Siemens Aktiengesellschaft Axial rotor portion and turbine rotor blade for a gas turbine
US10487674B2 (en) 2015-01-20 2019-11-26 Siemens Aktiengesellschaft Blade fastening mechanism having a securing device for turbine blades
US20200116034A1 (en) * 2018-10-10 2020-04-16 Rolls-Royce North American Technologies Inc. Turbine wheel assembly with retainer rings for ceramic matrix composite material blades

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2218873A1 (de) * 2009-02-17 2010-08-18 Siemens Aktiengesellschaft Rotorabschnitt für einen Rotor einer Turbomaschine, Laufschaufel für eine Turbomaschine und Blockierelement
US8251668B2 (en) * 2009-06-30 2012-08-28 General Electric Company Method and apparatus for assembling rotating machines
US20110255978A1 (en) * 2010-04-16 2011-10-20 Brian Denver Potter Locking Assembly For Circumferential Attachments
EP2860350A1 (de) * 2013-10-10 2015-04-15 Siemens Aktiengesellschaft Turbinenschaufel sowie Gasturbine
FR3021691B1 (fr) * 2014-06-03 2016-06-24 Snecma Rotor pour turbomachine comportant des aubes a plates-formes raportees
CN105065065A (zh) * 2015-08-07 2015-11-18 山东青能动力股份有限公司 一种枞树型叶根动叶片锁紧装置及其装配工艺
EP3611344A1 (de) * 2018-08-16 2020-02-19 Siemens Aktiengesellschaft Rotor mit umfangssicherung von dichtelementen

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US3266770A (en) * 1961-12-22 1966-08-16 Gen Electric Turbomachine rotor assembly
US3832092A (en) * 1973-10-19 1974-08-27 Gen Electric Device for locking turbomachinery blades
US5727927A (en) * 1995-05-06 1998-03-17 Mtu Motoren- Und Turbinen-Union Muenchen Gmbh Device for securing rotor blades to a rotor, especially of a gas turbine propulsion plant

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US3266770A (en) * 1961-12-22 1966-08-16 Gen Electric Turbomachine rotor assembly
US3832092A (en) * 1973-10-19 1974-08-27 Gen Electric Device for locking turbomachinery blades
US5727927A (en) * 1995-05-06 1998-03-17 Mtu Motoren- Und Turbinen-Union Muenchen Gmbh Device for securing rotor blades to a rotor, especially of a gas turbine propulsion plant

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9745852B2 (en) 2012-05-08 2017-08-29 Siemens Aktiengesellschaft Axial rotor portion and turbine rotor blade for a gas turbine
US20170037736A1 (en) * 2014-04-29 2017-02-09 Siemens Aktiengesellschaft Wheel disk assembly and method for assembling a wheel disk assembly
US10487674B2 (en) 2015-01-20 2019-11-26 Siemens Aktiengesellschaft Blade fastening mechanism having a securing device for turbine blades
US20200116034A1 (en) * 2018-10-10 2020-04-16 Rolls-Royce North American Technologies Inc. Turbine wheel assembly with retainer rings for ceramic matrix composite material blades
US11021974B2 (en) * 2018-10-10 2021-06-01 Rolls-Royce North American Technologies Inc. Turbine wheel assembly with retainer rings for ceramic matrix composite material blades

Also Published As

Publication number Publication date
EP1978211A1 (de) 2008-10-08
EP2129871A1 (de) 2009-12-09
WO2008122492A1 (de) 2008-10-16
CN101680304A (zh) 2010-03-24
RU2427713C2 (ru) 2011-08-27
CN101680304B (zh) 2013-09-04
JP2010523873A (ja) 2010-07-15
RU2009140744A (ru) 2011-05-10
JP4942844B2 (ja) 2012-05-30

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AS Assignment

Owner name: SIEMENS AKTIENGESELLSCHAFT, GERMANY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:ENGLE, DARREN T.;REEL/FRAME:023316/0981

Effective date: 20090716

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION