EP1207013B1 - Method for increasing the service life of rotor blade locking means - Google Patents

Method for increasing the service life of rotor blade locking means Download PDF

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Publication number
EP1207013B1
EP1207013B1 EP20010402916 EP01402916A EP1207013B1 EP 1207013 B1 EP1207013 B1 EP 1207013B1 EP 20010402916 EP20010402916 EP 20010402916 EP 01402916 A EP01402916 A EP 01402916A EP 1207013 B1 EP1207013 B1 EP 1207013B1
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EP
European Patent Office
Prior art keywords
sonotrode
rim
beads
groove
blade
Prior art date
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EP20010402916
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German (de)
French (fr)
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EP1207013A1 (en
Inventor
Benoît Jean Henri Berthelet
Francis Lucien Guy Chareyre
Willy Lionel Fradin
Hakim Hoffmann
Stéphane Michel Kerneis
Marie-Christine Marcelle Ntsama-Etoundi
Guillaume François Roger Simon
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Safran Aircraft Engines SAS
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Safran Aircraft Engines SAS
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Priority to FR0014767 priority Critical
Priority to FR0014767A priority patent/FR2816538B1/en
Application filed by Safran Aircraft Engines SAS filed Critical Safran Aircraft Engines SAS
Publication of EP1207013A1 publication Critical patent/EP1207013A1/en
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Publication of EP1207013B1 publication Critical patent/EP1207013B1/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24CABRASIVE OR RELATED BLASTING WITH PARTICULATE MATERIAL
    • B24C5/00Devices or accessories for generating abrasive blasts
    • B24C5/005Vibratory devices, e.g. for generating abrasive blasts by ultrasonic vibrations
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24BMACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B1/00Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes
    • B24B1/04Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes subjecting the grinding or polishing tools, the abrading or polishing medium or work to vibration, e.g. grinding with ultrasonic frequency
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24BMACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B39/00Burnishing machines or devices, i.e. requiring pressure members for compacting the surface zone; Accessories therefor
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24BMACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B39/00Burnishing machines or devices, i.e. requiring pressure members for compacting the surface zone; Accessories therefor
    • B24B39/02Burnishing machines or devices, i.e. requiring pressure members for compacting the surface zone; Accessories therefor designed for working internal surfaces of revolution
    • B24B39/026Impact burnishing
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24CABRASIVE OR RELATED BLASTING WITH PARTICULATE MATERIAL
    • B24C1/00Methods for use of abrasive blasting for producing particular effects; Use of auxiliary equipment in connection with such methods
    • B24C1/10Methods for use of abrasive blasting for producing particular effects; Use of auxiliary equipment in connection with such methods for compacting surfaces, e.g. shot-peening
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHER TREATMENTS
    • C21D7/00Modifying the physical properties of iron or steel by deformation
    • C21D7/02Modifying the physical properties of iron or steel by deformation by cold working
    • C21D7/04Modifying the physical properties of iron or steel by deformation by cold working of the surface
    • C21D7/06Modifying the physical properties of iron or steel by deformation by cold working of the surface by shot-peening or the like
    • 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
    • F01D5/28Selecting particular materials; Particular measures relating thereto; Measures against erosion or corrosion
    • F01D5/286Particular treatment of blades, e.g. to increase durability or resistance against corrosion or erosion
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05DINDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2200/00Mathematical features
    • F05D2200/20Special functions
    • F05D2200/24Special functions exponential
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/47Burnishing
    • Y10T29/479Burnishing by shot peening or blasting
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49316Impeller making
    • Y10T29/49318Repairing or disassembling
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49316Impeller making
    • Y10T29/4932Turbomachine making
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49316Impeller making
    • Y10T29/4932Turbomachine making
    • Y10T29/49321Assembling individual fluid flow interacting members, e.g., blades, vanes, buckets, on rotary support member
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49316Impeller making
    • Y10T29/4932Turbomachine making
    • Y10T29/49323Assembling fluid flow directing devices, e.g., stators, diaphragms, nozzles

Description

    Technical field of the invention
  • The invention relates to blade fasteners on a rotor and more particularly to a method for increasing its service life, this method implementing a particular form of the so-called "ultrasonic" shot blasting technique.
  • State of the art and problem
  • In an airplane turbojet, paddle rotors are traditionally made of a rim on the periphery of which are mounted a plurality of removable vanes. The mounting device is called in this patent application "blade attachment". This device comprises a dovetail groove machined in the rim and a foot also dovetail machined at the base of the blade, the assembly being effected by the interlocking of the foot in the groove. In a more elaborate form called "at the foot of fir", the dovetail has several "bulbs" of decreasing size, typically three bulbs, each bulb providing separately the function of the dovetail. In what follows, these two forms of fasteners will be said indifferently "dovetail". The blade roots are nested in the grooves by sliding with limited play, the feet then being immobilized without play by various locking means. It is understood that the grooves and the blade roots are the seat of high concentrations of stress and that their realization is therefore particularly neat. Turbojet rotors are usually made of steel, titanium alloy or superalloy based on nickel or chromium.
  • Usually, the rotors are blasted by blasting small balls of hard material with one or more compressed air nozzles. This shot peening has the effect of creating a compressive prestressing on the surface of the rotor to a depth of a few tenths of a millimeter, this prestressing delaying the appearance of cracks resulting from heavy stresses and thus increasing the life of the rotor. If necessary, shot peening is preceded by a heat treatment of the part to be treated to release residual stresses remaining in this room. In the case where certain parts of the part must not be blasted, they are usually protected by coating them with a material, such as an elastomer, of hardness sufficient to withstand the impacts of the balls.
  • A strong shot of Almen intensity of the order of F15A to F17A and to create on the surface of the rotor a compressive prestress of the order of 900 to 1100 MPa (mega pascals) is desirable, these rotors being usually steel , of titanium alloy or superalloys based on chromium or nickel. Unfortunately, such shot blasting greatly increases the roughness of the treated surfaces and thus reduces the wear resistance by vibratory friction of the surfaces of the grooves and blade roots in contact with each other.
  • This increase of the roughness of a surface subjected to a strong shot blasting by projection of small balls is attested by various documents:
    • Patent EP 0 922 532 [0005] column 1 lines 33 to 38. One of the recommended solutions is to reduce the intensity and coverage rate shot blasting paragraph [0006] lines 39-40. The same patent indicates line 41 that may result in a reduction in the service life of the part.
    • In the "Souder" magazine n ° 5 of September 1998, the study "The principle of the laser shock and its applications to the treatment of the materials" carries out a comparison of blast blasting with the conventional shot blasting and indicates page 13 before last paragraph that conventional shot blasting creates microcrats resulting from the impacts of the balls and increasing the roughness. According to the examples given in the first table on page 14, the roughness (Ra) of a machined surface can increase from 2.3 μm to 5.5 μm after strong shot blasting.
  • The article "Shot peening" published in 1992 by the CETIM page 105-123 reports on a national conference held on 25-26 September 1991 in Senlis, France. It indicates on page 108 before last paragraph that the blasting of a machined surface leads to an increase in the value of the roughness. This same article specifies in the last paragraph of this same page that we can reduce the roughness by performing shot blasting in several passes decreasing intensity. It can be understood that the initial shot blasting increases the roughness and that the lighter and lighter shots that follow reduce the roughness by leveling the blasted surface. This solution however has the disadvantage of being long because it takes several shot blasting, the first ensuring the prestressing of the surface shot blasting and subsequent shot blasting gradually reducing the roughness that appeared during the first shot blasting.
  • The US Patent 4888863 describes a method of manufacturing blade roots by electro-erosion machining followed by a shot peening treatment of Almen intensity between 4A and 6A.
  • The problem to be solved is to simultaneously increase the fatigue strength and vibration resistance of the rotors at the blade attachments, this increase should not cause a significant increase in the time and cost of manufacture of the rotors.
  • Ball blast blasting is currently undergoing a new form of implementation known as "ultrasound" in which the balls are no longer thrown by a jet nozzle but by the percussion on these balls from the surface of a sonotrode vibrating at frequencies of the order of 20 to 60 KHertz, the balls being held inside an enclosure, the piece to be blasted being according to its dimensions immersed inside the enclosure or presented in front of an opening of this enclosure.
  • We know by FR 2,743,742 an application of ultrasonic blasting to cookware to reduce microcavities previously created on the surface of the utensil to promote the attachment of a coating on a portion of the utensil. This patent indicates page 5 line 32 that the culinary article is aluminum. It is known that this material is soft, and its prestressing does not exceed 150 to 200 MPa. It is much lower than the prestressing sought from 900 to 1100 PMa. This patent also indicates that the surface obtained is smooth, but it specifies page 5 line 14 that blasting or "blasting" lasts from 0.5 to 5 seconds. Even for a soft material, it is therefore only a very light shot peening surface unrelated to the strong shots compression prestressing performed on aeronautical parts, the surfaces of these parts to be exposed to shot blasting for a period of four to ten minutes at least. This patent therefore does not provide a solution to the problem to be solved.
  • We also know by FR 2689431 , a method of ultrasonic blasting surface treatment according to which is formed an enclosure defined by a vibrating surface and movable walls perpendicular to the vibrating surface which abut against the surface of the wall to be treated.
  • Presentation of the invention
  • The invention provides a method for increasing the life of blade fasteners on a rotor according to claim 1.
  • Such a method is remarkable in that the shot blasting is carried out by the so-called "ultrasonic" method, the balls being projected by the percussion of a sonotrode placed in vibration, the balls being contained in a chamber and forming a fog with enclosure interior, the component to be shot blasted into contact with the fog of balls,
    and in that the blasting is carried out at an Almen number at least equal to F8A, for a duration T of 120% to 300% of the duration T1 necessary to obtain a normal recovery rate of 98%.
  • The inventors have observed that a strong ultrasonic shot blasting increases only slightly the roughness of the treated part, in contrast to conventional shot blasting using a jet nozzle of compressed air. The invention thus takes advantage of this unexpected property to increase the fatigue strength of the blade fasteners while maintaining good resistance to wear by vibrational friction.
  • An advantage of the invention is also to increase the vibration friction wear resistance of the blade fasteners, since the high compressive biasing of the component surfaces of the blade fasteners causes them to harden by work hardening.
  • Advantageously, beads having a diameter of at least 0.8 mm will be used in order to improve the blasting efficiency and to stabilize or reduce the roughness of the treated parts.
  • Advantageously, the compression prestressing will be at least equal to 500 MPa.
  • In a particular mode of implementation of the method, the invention proposes the application to so-called "axial" grooves on the rims of paddle rotors.
  • In another particular embodiment of the method, the invention proposes the application to so-called "annular" grooves on the rims of the blade rotors.
  • In another particular embodiment of the method, the invention proposes the application to the blade roots.
  • Description of figures
  • The invention will be better understood and the advantages that it provides will become more apparent in view of a detailed description of the properties of ultrasonic shot blasting, three examples of application to the blade fasteners and the accompanying figures.
  • The figure 1 illustrates the deformation of the material under the impact of the moving balls.
  • The figure 2 illustrates the rim of a rotor and reveals the so-called "axial" grooves at its periphery.
  • The figure 3 illustrates the mounting of a blade on a rim with axial grooves.
  • The Figures 4 and 5 illustrate by a front view and a profile view the ultrasonic shot blasting process of the axial grooves, the figure 4 being a sectional view along B on the figure 5 , this figure 5 being itself a sectional view along A on the figure 4 .
  • The figure 6 illustrates the rim of a so-called "annular" groove rotor.
  • The figure 7 illustrates the mounting of a blade on a rim with annular grooves.
  • The Figures 8 and 9 illustrate by a front view and a profile view the ultrasonic shot blasting process of the annular grooves. Following the example of the previous example, the figure 8 is a section along D on the figure 9 , this figure 9 being itself a sectional view along C on the figure 8 ..
  • The Figures 10 and 11 illustrate by a front view and a view from above the method of ultrasonic blasting of the blade roots, the figure 10 being a sectional view along E on the figure 11 .
  • detailed description
  • Tests have shown that high-intensity "ultrasonic" shot blasting does not substantially increase the roughness of the treated surfaces, unlike conventional shot blast blasting using a jet nozzle. Table below shows some comparative results made on a piece of nickel-chromium base refractory superalloy:
    the first line indicates the roughness (Ra) measured before blasting,
    the second line indicates the roughnesses (Ra) measured on these same surfaces after a conventional shot peening of Almen index equal to F17A and a pre-stressing under the blasted surface up to 1000 MPa,
    the third line indicates the roughnesses (Ra) measured on these same surfaces after ultrasonic peening equivalent to the previous Almen index equal to F17A with prestressing under the surface reaching up to 1000 MPa, Surface No. 1 (milled) Surface n ° 2 (tour) Roughness (Ra) before shot blasting 0.27 μm 0.90 μm Roughness (Ra) after conventional shot blasting, Almen index = F17A, balls ∅ = 0.315 mm. 1.53 μm 1.94 μm Roughness after US shot blasting, Almen index = F17A, balls ∅ = 1.5mm 0.47 μm 0.93 μm
  • In a first example shown in column 1, the milled surface number 1 with a roughness Ra = 0.27 μm has a roughness increase of 1.67 μm after conventional shot blasting while its roughness only increases by 0.2. μm with ultrasonic shot blasting, this No. 1 surface being arranged parallel to the sonotrode.
  • In a second example illustrated in column 2, the surface 2 machined by turning with a Ra = 0.90 μm sees its roughness increase of 0.63 microns after conventional shot peening, whereas this roughness remains substantially unchanged after shot peening. ultrasound, this surface No. 2 being this time arranged perpendicular to the sonotrode.
  • This remarkable property of ultrasonic shot blasting, which is to allow a strong shot blasting without substantially increasing the roughness of the treated surface, could be explained in this way in view of the figure 1 : The balls 1 supplied with kinetic energy by the percussions of the sonotrode in vibration bounce on the sonotrode itself, on the walls of the enclosure and on the surface 3 of the part 2 subjected to shot blasting, these balls 1 then bouncing on this surface with an angle α, β of random incidence in a substantially uniform distribution between 0 ° and 90 ° and in any direction. In these conditions :
    • The balls 1a impacting the surface to be blasted with an angle α close to the perpendicular to this surface will be effective to create at the points of impact a significant compressive prestressing, these beads however leaving on the impacted surface 3 craters 4 surrounded by beads 5 forming asperities.
    • Conversely, the balls 1b impacting the surface 3 with a small angle β, that is to say, shaving the surface 3, tend to level the beads 5 and at least partially resorb the craters 4, these balls 1b being well obviously little or not at all effective to create a sufficient compression biasing. This role of the grazing balls is confirmed by the previous table. Indeed, the surface No. 2 preferably receives grazing balls because it is shot blasted ultrasonically in a position perpendicular to the sonotrode, which explains why the roughness does not substantially increase.
  • It can thus be said that a strong shot peening which does not substantially increase the roughness of the blasted surface 3 must be able to combine on the treated surface impacts of balls 1a with angles of incidence α close to the perpendicular to this surface 3 and impacts of balls 1b shaving this surface. An angle of incidence α close to the perpendicular means an angle α at least equal to 45 °, the effectiveness of the impact being all the better that this angle α is close to 90 °. By an angle of incidence β grazing means an angle β less than 45 ° and preferably between 15 ° and 30 °.
  • It will be noted that the strong blast blasting according to the invention also involves a so-called "overlap" rate ranging from 120% to 300%, that is to say that blasting is carried out for a duration T equal to 120% to 300% of the T1 time required to obtain a normal recovery rate of 98%, the normal recovery rate being the ratio between the impacted surface and the total surface exposed to shot blasting.
  • In the case of conventional shot blasting, on the contrary, the balls strike the blasted surface with an angle of incidence and a preferential direction, this angle of incidence must be sufficient to prestress the blasted surface. As a result, the beads forming around the craters are not leveled and instead tend to gather in waves clearly visible under the microscope with a magnification x50 to x100, the craters tending themselves to gather in furrows more or less perpendicular to the waves.
  • A significant advantage of ultrasonic shot blasting is that its implementation requires only a small amount of beads. It is therefore possible in this case to use high quality beads comparable to ball bearings for steel or ceramic rolling bearings. Unlike conventional shots:
    • these balls are perfectly spherical and therefore give a better surface state,
    • these very hard balls do not break and therefore do not produce sharp edges likely to alter the surface state of the blasted piece.
  • We will now refer to the figure 2 . The blade rotor comprises a rim 10 having a general shape of revolution around a geometric axis 11, this rim 10 being limited radially outwards by a peripheral surface 12 and laterally by two sidewalls 13. The rim 10 comprises at its periphery 12 a plurality of grooves 14 substantially rectilinear said "axial" each having a mouth 15 extended laterally by two side openings 16, the mouth 15 opening on the periphery 12, the side openings 16 opening on the sidewalls 13. The grooves 14 have a substantially trapezoidal profile called "dovetail" with a mouth 15 narrower. These grooves 14 may be parallel to the geometric axis 11 or oblique. They can be rectilinear or in an arc.
  • We will now refer to the figure 3 . A blade 20 comprises successively from top to bottom in this figure a thin blade 21, a platform 22 extending laterally on each side of the blade 20 and a foot 23 of substantially trapezoidal shape and complementary to that of the groove 14 The blade 20 is engaged by its foot 23 in the groove 14 with limited play, the foot 23 then being immobilized in the groove 14 by various locking means not shown. The foot 23 comes into contact with the groove 14 along two lines of contact 24 located at the rear of the mouth 15 and recessed from this mouth 15. The attachment 26 of the blade 20 comprises the groove 14 and the foot 23.
  • We will now refer simultaneously to Figures 4 and 5 . The sonotrode 30 comprises a vibrating surface 31 capable of being introduced into the mouth 15 of the groove 14. The sonotrode 30 slides in a sheath 32 with a clearance E less than the diameter of the balls 1. The sealing of the beads of the sonotrode 30 relative to the mouth 15 can be provided by the sleeve 32. In a preferred embodiment however, this sealing is more simply ensured by giving the sonotrode 30 a shape complementary to that of the mouth 15, for example rectangular in the case of straight grooves, with a clearance E less than the diameter of the balls 1. The sleeve 32 supports two shutters or ears 33 on either side of the sonotrode 30, these ears being capable of covering the openings 16 of the groove 14 with a clearance E less than the diameter of the balls 1. It is understood that the sonotrode 30 and the ears 33 cooperate to close the groove 14 and contain the balls in this groove 14 during shot blasting.
    With such a device, the method of ultrasonic blasting of the axial grooves 14 comprises the following operations:
    • arranging the rim 10 above the sonotrode 30 in a position suitable for bringing each groove 14 above the sonotrode 30 by rotating the rim 10 along its geometric axis 11,
    • have a dose of beads 1 on the sonotrode 30, the sonotrode preferably being retracted into the sheath 32 so as to constitute above its vibrating surface 31 a container capable of containing the balls 1,
    • rotating the rim 10 to successively bring each groove 14 above the sonotrode 30, each groove 14 then being the subject of the following operations:
    • covering the openings 16 with the ears 33 and bring the sonotrode 30 into the mouth 15 of the groove 14, this operation is preferably done by simultaneously raising the sonotrode 30 and the sheath 32 until the ears 33 cover the openings 16, the sonotrode 30 then being raised alone in the mouth 15, which simultaneously has the effect of bringing the balls 1 into the groove 14 and put the sonotrode 30 in the working position,
    • blasting the groove 14 by vibrating the sonotrode 30,
    • remove the sonotrode 30.
  • It is advantageous to bring the vibrating surface 31 of the sonotrode 30 into the mouth 15 itself, the vibrating surface 31 being substantially at the narrowest section of this mouth. This has the effect of:
    • to improve the homogeneity and the isotropy of the ball mist 1 produced inside the groove 14, in order to better combine a high prestressing and a low roughness especially on the lines of contact 24 at the rear and set back from the mouth 15,
    • to protect from blasting the mouth 15 itself, this mouth 15 forming asperities and being thereby liable to be crushed by the impacts of the balls 1.
  • We will now refer to the figure 6 . The rotor blade comprises in this second example a rim 10 having a general shape of revolution around a geometric axis 11, the rim 10 being limited radially outwardly by an annular peripheral surface 12. The rim 10 comprises in this example at the periphery 12 three annular grooves 14 whose descriptions are identical: Each annular groove 14 has a mouth 15 also annular and opening on the periphery 12. Each groove also has a local opening 18 also opening on the periphery 12, this so-called "local" opening 18. Each annular groove 14 has a substantially trapezoidal profile called "dovetail" with a mouth 15 narrower.
  • We will now refer to the figure 7 . A blade 20 comprises successively from top to bottom in this figure a thin blade 21, a platform 22 extending laterally on each side of the blade 20 and a foot 23 of substantially trapezoidal shape and complementary to that of the groove 14 , the foot 23 being in this example disposed transversely to the blade 21. This figure also shows for information the section 21a of the blade 21. The blade 20 is engaged by its foot 23 in the annular groove 14 with a limited clearance and blocked by locking means not shown. Each annular groove 14 thus receives a plurality of blades 20 whose foot 23 is introduced through the local opening, referenced 18 on the figure 6 , and brought into position by sliding in the annular groove 14. The foot 23 comes into contact with the annular groove 14 along two annular contact lines 24 also located at the rear of the mouth 15. By the term fasteners 26 of the blades 20, is also meant the annular groove 14 and the feet 23.
  • We will now refer simultaneously to Figures 8 and 9 . The sonotrode 30 comprises a vibrating surface 31 capable of being introduced into the mouth 15 of the groove 14. The sonotrode 30 slides in a sheath 32 with a clearance E less than the diameter of the balls 1. The sealing of the beads of the sonotrode 30 relative to the mouth 15 may be provided by the sheath or by any other means. In a preferred embodiment, however, this seal is more simply provided by giving the sonotrode 30 a rectangular section with a width equal to that of the mouth 15 entrenched with a clearance E less than the diameter of the balls 1. The sleeve 32 supports two ears 33 on either side of the sonotrode 30, these ears being able to slide in the annular groove 14 with a clearance E less than the diameter of the balls 1. It is understood that the sonotrode 30 and the ears 33 cooperate to contain the balls 1 inside a portion of the annular groove 14 and against the walls of this groove 14.
  • With such a device, the method of ultrasonically blasting an annular groove 14 comprises the following operations:
    • arranging the rim 10 above the sonotrode 30 in a position suitable for scrolling the annular groove 14 above the sonotrode 30 by rotation of the rim 10 along its geometric axis 11,
    • have a dose of beads 1 on the sonotrode 30, the sonotrode preferably being retracted into the sheath 32 so as to constitute above its vibrating surface 31 a container capable of containing the balls 1,
    • present the local opening 18 above the sonotrode 30,
    • bring the sonotrode 30 and the two ears 33 into the local opening 18, the sonotrode 30 being at the mouth 15 and in alignment with this mouth 15, the two ears 33 being on either side of the sonotrode 30 and in alignment with the groove 14,
    • rotating the rim 10 and vibrating the sonotrode 30 when the two ears 33 and the sonotrode 30 are in the annular groove 14,
    • to stop the sonotrode 30 as soon as an ear 33 leaves in the local opening 18,
    • stop the rotation of the rim 10 when the two ears 33 and the sonotrode 30 are in the local opening 18.
  • We will now refer simultaneously to Figures 10 and 11 . To blast the feet 23 of the blades 20, an enclosure 40 is used, the bottom 41 of which has an opening 42 through which a sonotrode 30 passes with a clearance E less than the diameter of the balls 1, the enclosure 40 being covered by a cover 45 of preferably thin, the cover 45 having a plurality of openings 46 of complementary shape to the feet 23 to be treated, the distance between the cover 45 and the sonotrode 30 being at least equal to the height of the feet 23 so that the bases 23a of the feet 23 do not touch the sonotrode 30.
    With such a device, the ultrasonic blasting process of the feet 23 of the blades 20 comprises the following operations:
    • introduce a dose of beads 1 in the chamber 40,
    • inserting the feet 23 into the openings 46 of the cover 45 and immobilizing the vanes 20 on the cover 45,
    • put the sonotrode 30 in vibration to perform shot blasting.
  • An advantage of the method is to avoid coating by a protective coating parts of the blade which are not to be blasted, namely the platform 22 and the blade 21, this protection being provided by the cover, the platform 22 and the blade 21 remaining behind the cover 45 outside the enclosure 40.
  • Advantageously, the feet 23 are positioned above the vibrating surface 31 of the sonotrode 30 to ensure uniform shot blasting of all the feet 23.
  • Advantageously, the blades 20 having a cooling cavity opening at the base 23a of the foot 23, this base 23a is positioned at a distance from the sonotrode 30 less than the diameter of the balls 1 in order to prevent the balls 1 from entering the cavity cooling.

Claims (8)

  1. For a rotor blade assembly comprising a rotor and a plurality of blades removably attached to said rotor, said rotor comprising a rim (10) having a periphery (12) to which each of said plurality of blades (20) is attached by attachments (26) comprising first and second components (14, 23), said first component (14) comprising a dovetail groove arranged in said periphery (12) of said rim (10), and said second component (23) comprising a root (23) formed on said blade, said root (23) being of a shape that complements said groove and being able to be fitted into said groove so as to attach said blade to said rim (10), a method for extending the life of said attachments by peening a surface of at least one of said first and second components (14, 23) so as to create compressive prestress at said surface, characterized by the fact that said method comprising the steps of:
    a) peening is effected by a ultrasonic method providing a sonotrode (30) which is adapted to be vibrated ultrasonically;
    forming a chamber (40) which is delimited at least partly by said sonotrode and the surface which is to be peened;
    providing a plurality of beads (1) in said chamber (40); and
    vibrating said sonotrode (30) whereby said beads (1) are mobilized in said chamber (40) by the percussion of said sonotrode and forming a mist so that said beads (1) are projected against the surface of said component (14, 23) to effect untrasonic peening of said surface,
    b) said peening being effected with an Almen intensity at least equal to F8A, during a duration T of 120% to 300% of the duration T1 needed for obtaining a normal coverage of 98%.
  2. A method according to claim 1, wherein said beads (1) have a diameter at least equal to 0.8 mm.
  3. A method according to claim 1 or 2, wherein said component is made of a material selected from the group consisting of steel, titanium alloy, chrome-based superalloy, or nickel-based superalloy, and wherein the prestressing is at least 500 MPa.
  4. A method according to any claims 1 to 3, wherein said dovetail grooves (14) are arranged axially in said periphery of said rim, said axial grooves (14) being approximately straight and open at each end (16), and wherein said sonotrode is capable of being introduced into said grooves and includes means for sealing said sonotrode in said grooves and two wings (33) capable of covering said open (16) ends of said grooves and of closing them off with a clearance E smaller than the diameter of said beads (1), said method further comprising the steps of:
    - arranging said rim (10) above said sonotrode (30) in an appropriate position for bringing each axial groove (14) over said sonotrode (30) by rotating said rim (10) about its geometric axis (11);
    - arranging said plurality of beads (1) on said sonotrode (30);
    - turning said rim (10) to bring each axial groove (14) in turn over said sonotrode (30), each axial groove (14) then being subjected to the steps of:
    - covering said open ends (16) with said wings (33) and bringing said sonotrode (30) into said axial groove (14), peening said axial groove by setting said sonotrode (30) in vibration,
    - withdrawing said sonotrode (30).
  5. A method according to any claims 1 to 3, wherein said dovetail grove is arranged annularly in said periphery of said rim, said annular groove including a mouth (15), and a local opening (18) for insertion or removal of said roots (23) of said blades (20), and wherein said sonotrode (30) is capable of being introduced into said mouth (15) of said annular groove (14) and includes means for sealing said sonotrode (30) in said mouth (15), and two wings (33) are capable of passing into said annular groove (14) with a clearance E smaller than the diameter of said beads (1), said method further comprising the steps of:
    - arranging said rim (10) over said sonotrode (30) in an appropriate position for causing said annular groove (14) to travel over said sonotrode (30) by rotating said rim (10) about its geometric axis (11);
    - arranging said plurality of beads (1) on said sonotrode (30);
    - presenting said local opening (18) over said sonotrode (30);
    - bringing said sonotrode (30) and said two wings (33) into said local opening (18), said sonotrode (30) being level with said mouth (15) and aligned with said mouth (15), said two wings (33) lying one on each side of said sonotrode (30) and aligned with said axial groove (14);
    - turning said rim (10) and setting said sonotrode (30) in vibration when said two wings (33) and said sonotrode (30) are in said annular groove (14);
    - stopping said sonotrode(33) as soon as a wing (33) comes out in said local opening (18);
    - stopping rotation when both wings (33) and said sonotrode (30) are in said local opening (18).
  6. A method according to any claims 1 to 3, when applied to the peening of blade roots, wherein use is made of a chamber (40) including a bottom (41), said bottom having an opening (42) through which said sonotrode passes with a clearance E smaller than the diameter of said beads, said chamber being covered by a thin lid (45), said lid having a number of openings (46) of a shape that complements said roots, the distance between said lid (45) and said sonotrode being at least equal to the height of said roots, said method further comprising the steps of:
    - introducing said plurality of beads (1) into said chamber (40);
    - introducing said roots (23) into said openings (46) of the lid (45) and immobilizing said blades (1);
    - setting said sonotrode (30) in vibration to carry out said peening.
  7. A method according to claim 6, wherein said sonotrode (30) has a vibrating surface and all of said blades (20) are positioned above said vibrating surface (31).
  8. A method according to claim 7, wherein said blade (20) roots each have a base, and a cooling cavity opening at said base (23a) of said root (23), and wherein said base (23a) is positioned at a distance from said sonotrode (30) that is smaller than the diameter of said beads (1).
EP20010402916 2000-11-16 2001-11-14 Method for increasing the service life of rotor blade locking means Active EP1207013B1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
FR0014767 2000-11-16
FR0014767A FR2816538B1 (en) 2000-11-16 2000-11-16 Process for increasing the lifetime of aub attaches on a rotor

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EP1207013A1 EP1207013A1 (en) 2002-05-22
EP1207013B1 true EP1207013B1 (en) 2012-01-11

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EP (1) EP1207013B1 (en)
JP (1) JP3974385B2 (en)
CA (1) CA2363306C (en)
FR (1) FR2816538B1 (en)
SG (1) SG114512A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102016100663A1 (en) * 2016-01-15 2017-07-20 Rolls-Royce Deutschland Ltd & Co Kg Apparatus and method for beam hardening of surface areas, in particular fir tree profiles

Families Citing this family (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7028378B2 (en) * 2000-10-12 2006-04-18 Sonats-Societe Des Nouvelles Applications Des Techniques De Surfaces Method of shot blasting and a machine for implementing such a method
JP3951905B2 (en) * 2002-04-25 2007-08-01 日産自動車株式会社 Magnetic steel sheet forming body for rotor core, rotor for built-in permanent magnet type rotating electric machine using the same, method for producing electromagnetic steel sheet forming body for rotor core, and permanent magnet built-in type rotating electric machine
JP4189201B2 (en) * 2002-10-30 2008-12-03 新日本製鐵株式会社 Method for improving toughness of heat-affected zone in steel welded joints
US7399371B2 (en) * 2004-04-16 2008-07-15 Nippon Steel Corporation Treatment method for improving fatigue life and long-life metal material treated by using same treatment
DE102004029546A1 (en) * 2004-06-19 2006-01-05 Mtu Aero Engines Gmbh Method and apparatus for surface blasting gas turbine blades in the area of their blade roots
FR2873609B1 (en) * 2004-07-30 2008-02-22 Sonats Soc Des Nouvelles Appli Projectiles, devices and ultrasonic scratching devices and parts thus processed
US20060021410A1 (en) * 2004-07-30 2006-02-02 Sonats-Societe Des Nouvelles Applications Des Techniques De Surfaces Shot, devices, and installations for ultrasonic peening, and parts treated thereby
DE102004037954A1 (en) * 2004-08-05 2006-03-16 Mtu Aero Engines Gmbh Device for surface blasting of components
DE102004059592B4 (en) * 2004-12-10 2014-09-04 MTU Aero Engines AG Method for surface blasting of cavities, in particular of cavities on gas turbines
US7147634B2 (en) 2005-05-12 2006-12-12 Orion Industries, Ltd. Electrosurgical electrode and method of manufacturing same
US7992416B2 (en) * 2005-05-12 2011-08-09 General Electric Company Ultrasonic peening treatment of assembled components
US8814861B2 (en) 2005-05-12 2014-08-26 Innovatech, Llc Electrosurgical electrode and method of manufacturing same
FR2889669B1 (en) * 2005-08-12 2007-11-02 Snecma Metal piece treated by compressing under coats. method for obtaining such a part
DE102005054866A1 (en) * 2005-11-17 2007-05-31 Mtu Aero Engines Gmbh Method for producing metallic components, in particular for turbomachinery, with small edge radii
US7516547B2 (en) * 2005-12-21 2009-04-14 General Electric Company Dovetail surface enhancement for durability
DE102006016949A1 (en) * 2006-04-11 2007-10-25 Mtu Aero Engines Gmbh Method for producing a component
WO2007137902A1 (en) * 2006-05-26 2007-12-06 Siemens Aktiengesellschaft Peening device
DE102007009470A1 (en) * 2007-02-27 2008-08-28 Daimler Ag Shot-peening mask for gas turbine gear wheel tooth defines limits of area for differential treatment
FR2930184B1 (en) * 2008-04-18 2010-12-31 Snecma Process for ultrasonic crushing of turbomachine parts.
JP5218228B2 (en) * 2008-04-23 2013-06-26 新東工業株式会社 Conveying device and blasting device
US8240042B2 (en) * 2008-05-12 2012-08-14 Wood Group Heavy Industrial Turbines Ag Methods of maintaining turbine discs to avert critical bucket attachment dovetail cracks
JP5567023B2 (en) * 2008-10-23 2014-08-06 ダブリュ・ダブリュ・テクノロジー・アクチェンゲゼルシャフトWw Technology Ag Augmentation device for fixing an object to hard tissue
DE102009021582A1 (en) * 2009-05-15 2010-12-02 Rolls-Royce Deutschland Ltd & Co Kg Process for surface hardening and smoothing of metallic components
DE102009040324B4 (en) * 2009-09-05 2016-11-17 MTU Aero Engines AG Process for heat treatment of gas turbine blades
US8794925B2 (en) * 2010-08-24 2014-08-05 United Technologies Corporation Root region of a blade for a gas turbine engine
US20130183157A1 (en) 2012-01-17 2013-07-18 Venkatarama K. Seetharaman Method of surface treatment for dovetail in gas turbine engine fan blade
US8959738B2 (en) * 2012-03-21 2015-02-24 General Electric Company Process of repairing a component, a repair tool for a component, and a component
US10633985B2 (en) * 2012-06-25 2020-04-28 General Electric Company System having blade segment with curved mounting geometry
US9200521B2 (en) * 2012-10-30 2015-12-01 General Electric Company Components with micro cooled coating layer and methods of manufacture
US20140255620A1 (en) * 2013-03-06 2014-09-11 Rolls-Royce Corporation Sonic grain refinement of laser deposits
US10018047B2 (en) * 2013-12-12 2018-07-10 United Technologies Corporation Methods of roughing and finishing engine hardware
CN107283119B (en) * 2017-05-19 2019-10-22 航天材料及工艺研究所 A kind of composite material variable cross-section dovetail blind slot processing method
DE102018203777A1 (en) * 2018-03-13 2019-09-19 MTU Aero Engines AG Aftertreatment process for blades of a turbomachine

Family Cites Families (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3482423A (en) * 1968-02-26 1969-12-09 Metal Improvement Co Blade peening masking apparatus
US3668913A (en) * 1970-10-05 1972-06-13 Metal Improvement Co Apparatus for shot-peening turbine blades
US4426867A (en) * 1981-09-10 1984-01-24 United Technologies Corporation Method of peening airfoils and thin edged workpieces
US4419875A (en) * 1981-09-10 1983-12-13 Progressive Blasting Systems, Inc. Article manipulator mechanism for accelerated shot treating apparatus
US4888863A (en) 1988-03-21 1989-12-26 Westinghouse Electric Corp. Method and apparatus for producing turbine blade roots
FR2689431B1 (en) 1992-04-06 1995-10-20 Teknoson Method and device, in particular for ultrasonic hardening of metal parts.
FR2713974B1 (en) * 1993-12-22 1996-01-19 Snecma Shot peening device for surfaces not accessible by a straight pipe.
FR2714629B1 (en) * 1993-12-30 1996-06-07 Teknoson Sa Method and device for deburring mechanical parts.
FR2715884B1 (en) * 1994-02-04 1996-04-12 Gec Alsthom Electromec Method and device for the surface treatment and the prestressing of the interior wall of a cavity.
US5620307A (en) * 1995-03-06 1997-04-15 General Electric Company Laser shock peened gas turbine engine blade tip
US5735044A (en) * 1995-12-12 1998-04-07 General Electric Company Laser shock peening for gas turbine engine weld repair
FR2743742B1 (en) 1996-01-24 1998-04-03 Seb Sa Process for treating a metal surface and manufacturing a culinary article
US5813265A (en) 1997-12-12 1998-09-29 General Electric Company Balanced electromagnetic peening
US5950470A (en) * 1998-09-09 1999-09-14 United Technologies Corporation Method and apparatus for peening the internal surface of a non-ferromagnetic hollow part
US6170308B1 (en) * 1999-07-20 2001-01-09 United Technologies Corporation Method for peening the internal surface of a hollow part
FR2801236B1 (en) 1999-11-18 2001-12-21 Snecma Method and machine for ultrasonic blasting of workpieces on a wheel
FR2801322B1 (en) * 1999-11-18 2002-02-08 Snecma Method for ultrasonic blasting of large dimensional annular surfaces on thin parts
US6340500B1 (en) * 2000-05-11 2002-01-22 General Electric Company Thermal barrier coating system with improved aluminide bond coat and method therefor

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102016100663A1 (en) * 2016-01-15 2017-07-20 Rolls-Royce Deutschland Ltd & Co Kg Apparatus and method for beam hardening of surface areas, in particular fir tree profiles

Also Published As

Publication number Publication date
EP1207013A1 (en) 2002-05-22
FR2816538A1 (en) 2002-05-17
CA2363306C (en) 2008-04-01
CA2363306A1 (en) 2002-05-16
SG114512A1 (en) 2005-09-28
JP3974385B2 (en) 2007-09-12
US20020124402A1 (en) 2002-09-12
FR2816538B1 (en) 2003-01-17
JP2002200562A (en) 2002-07-16
US6536109B2 (en) 2003-03-25

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