EP0666142B1 - Procédé et dispositif pour le traitement de surface et la mise en précontrainte de la paroi intérieure d'une cavité - Google Patents

Procédé et dispositif pour le traitement de surface et la mise en précontrainte de la paroi intérieure d'une cavité Download PDF

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Publication number
EP0666142B1
EP0666142B1 EP95400207A EP95400207A EP0666142B1 EP 0666142 B1 EP0666142 B1 EP 0666142B1 EP 95400207 A EP95400207 A EP 95400207A EP 95400207 A EP95400207 A EP 95400207A EP 0666142 B1 EP0666142 B1 EP 0666142B1
Authority
EP
European Patent Office
Prior art keywords
vibrator
cavity
orifice
tubular portion
balls
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP95400207A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0666142A1 (fr
Inventor
André Coulon
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.)
Alstom SA
Original Assignee
GEC Alsthom Electromecanique SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by GEC Alsthom Electromecanique SA filed Critical GEC Alsthom Electromecanique SA
Publication of EP0666142A1 publication Critical patent/EP0666142A1/fr
Application granted granted Critical
Publication of EP0666142B1 publication Critical patent/EP0666142B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24C—ABRASIVE OR RELATED BLASTING WITH PARTICULATE MATERIAL
    • B24C5/00—Devices or accessories for generating abrasive blasts
    • B24C5/005—Vibratory devices, e.g. for generating abrasive blasts by ultrasonic vibrations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24C—ABRASIVE OR RELATED BLASTING WITH PARTICULATE MATERIAL
    • B24C1/00—Methods for use of abrasive blasting for producing particular effects; Use of auxiliary equipment in connection with such methods
    • B24C1/10—Methods 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24C—ABRASIVE OR RELATED BLASTING WITH PARTICULATE MATERIAL
    • B24C3/00—Abrasive blasting machines or devices; Plants
    • B24C3/32—Abrasive blasting machines or devices; Plants designed for abrasive blasting of particular work, e.g. the internal surfaces of cylinder blocks
    • B24C3/325—Abrasive blasting machines or devices; Plants designed for abrasive blasting of particular work, e.g. the internal surfaces of cylinder blocks for internal surfaces, e.g. of tubes
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D7/00—Modifying the physical properties of iron or steel by deformation
    • C21D7/02—Modifying the physical properties of iron or steel by deformation by cold working
    • C21D7/04—Modifying the physical properties of iron or steel by deformation by cold working of the surface
    • C21D7/06—Modifying the physical properties of iron or steel by deformation by cold working of the surface by shot-peening or the like
    • Y—GENERAL 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
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S451/00—Abrading
    • Y10S451/91—Ultrasonic
    • Y—GENERAL 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
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S72/00—Metal deforming
    • Y10S72/71—Vibrating

Definitions

  • the present invention relates to a method for processing surface and compression preload of the inner wall of a cavity comprising at least one hole, tube, bore or hole machined in a mechanical part.
  • Shot blasting usual by projection of balls through nozzles oriented towards the part to be treated gives no results on the walls of a cavity as defined above, since the only possible movement of the balls in the cavity takes place in a direction substantially parallel to the walls to be treated.
  • This assembly consists in broaching two nested combs, the comb of dawn and the comb of the disc by two or three fixing pins passing through the nested combs in part.
  • the usual assembly of the blades consists in making independently on dawn and on disk a pre-hole of diameter smaller than that of the final hole, before installation place of dawn on the disc.
  • the dimensioning of the hole is made by means of a tool such as for example a reamer.
  • the surface condition of the hole is poor quality, and the tool, tangentially hardening the metal, induces residual tensile stresses, which causes great sensitivity to cracking under stress and increased sensitivity if corrosions are possible. For these reasons, an improvement in the state of surface is particularly needed in this area where a high reliability of assembly is required.
  • the method according to the invention proposes to overcome the disadvantages of the prior art and improves the surface finish in a sufficient way to satisfy to the highest requirements in areas where the quality is synonymous with safety.
  • the vibrator sometimes called a sonotrode is a shaped device pot, made of a low capacity material vibration damping (for example titanium), intended to amplify or maintain a vibratory movement disposed near said orifice of said cavity and excited by an exciter-vibrator.
  • a pot-shaped vibrator having a swollen part and a tubular part and one energizes said vibrator at its or one of its frequencies clean.
  • a plate is used as reflector made of a metal or metal alloy identical to that of the vibrator.
  • the dimensions of the vibrator in such a way that we get a knot of vibration in the swollen part and a vibration belly at the free end of the tubular part.
  • the device according to claim 8 includes a vibrator, a exciter-vibrator arranged to excite the vibrator, and the shot made up of balls of predetermined diameter, these balls being intended to resonate vibratory inside said cavity, when the vibrator is mounted near the orifice of this cavity and excited by said exciter-vibrator.
  • the vibrator-exciter is arranged to excite the vibrator to its or one of its natural frequencies.
  • said vibrator comprises a swollen part and a tubular part and in that its dimensions are chosen so that a vibration node is forms in its swollen part and that a vibrating belly form at the free end of its tubular part.
  • said tubular part has a free end whose transverse dimension is slightly less than that of the orifice of said cavity.
  • said tubular part has a support flange at its free end.
  • the device comprises a reflector arranged to be pressed against a second orifice of said cavity, opposite said orifice near which is disposed the vibrator.
  • turbine blades 10 are mounted on a disc 11 by means of two combs nested 12 and are made integral with the disc, by example by three pins 13 which are driven into suitable bores made through the disc 11 and the nested combs 12.
  • the bore must be very precise and that the surface condition is critical, it is necessary to perform a surfacing and a stressing of compression of the internal wall of the cavity defined by said bore.
  • the device used is represented in two variants of realization by figures 3 and 4.
  • This device essentially comprises a vibrator 20 in pot shape, one end of which 21 is defined by a tubular element 22 of determined length.
  • a vibrator-exciter 23 high frequency is associated with this vibrator for ensure his excitement.
  • the tubular element 22 of the vibrator 20 has a diameter slightly smaller than that of cavity 24 and its end is engaged a few millimeters in this cavity.
  • the tubular element 22 of the vibrator 20 is provided with a flange 26 of annular shape surrounding the free end of this item. This variant allows the use of the vibrator for different diameters of cavities.
  • the flange is plated against the wall surrounding orifice 25.
  • the cavity 24 is through and a reflector 27 is used to close the orifice 28 opposite the orifice 25.
  • This reflector consists of a flat plate which is preferably made in the same metal as the vibrator, for example titanium or alloy titanium.
  • the reflector can be replaced by a jet of compressed air sent inside of the tube to limit the field of movement of the balls.
  • the actual surface treatment is done by balls 29 preferably in steel which are previously placed in the cavity and which are vibrated by the vibrator 20 which produces a vibrational resonance under excitation of exciter-vibrator 23.
  • the length and diameter of the vibrator, and in particular of the tubular element 22, are chosen in such a way that one of its frequencies is well determined and is between 10 and 30 MHz and preferably about 20 MHz.
  • the selected material for the manufacture of the vibrator is a metal or an alloy metallic with low damping coefficient vibratory such as for example titanium.
  • the reflector 27 is used to return the balls 29 in the field to treat.
  • FIG. 5 represents the vibrator 20 seen in axial section and helps to understand how it works.
  • This vibrator is excited at its natural frequency or at one of its frequencies clean.
  • the node or one of the vibration nodes 30 is product in its swollen part 31.
  • the belly or one of the vibration bellies 32 is located at the end of the element tubular 22. The length of this tubular element is determined so that a vibration belly corresponds to its end from where the balls are injected in the cavity.
  • the balls Under the effect of the excitation of the vibrator, the balls are set in motion very violent and strike the walls to blast in all directions and a large number of times, which causes significant matting of said walls and, therefore, a leveling of the traces of the reamer while inducing residual compression stresses over a thickness which may be greater than that of a classic shot blasting.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Apparatuses For Generation Of Mechanical Vibrations (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
EP95400207A 1994-02-04 1995-02-01 Procédé et dispositif pour le traitement de surface et la mise en précontrainte de la paroi intérieure d'une cavité Expired - Lifetime EP0666142B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9401275A FR2715884B1 (fr) 1994-02-04 1994-02-04 Procédé et dispositif pour le traitement de surface et la mise en précontrainte de la paroi intérieure d'une cavité.
FR9401275 1994-02-04

Publications (2)

Publication Number Publication Date
EP0666142A1 EP0666142A1 (fr) 1995-08-09
EP0666142B1 true EP0666142B1 (fr) 1998-11-18

Family

ID=9459791

Family Applications (1)

Application Number Title Priority Date Filing Date
EP95400207A Expired - Lifetime EP0666142B1 (fr) 1994-02-04 1995-02-01 Procédé et dispositif pour le traitement de surface et la mise en précontrainte de la paroi intérieure d'une cavité

Country Status (5)

Country Link
US (1) US5509286A (ja)
EP (1) EP0666142B1 (ja)
JP (1) JPH07224606A (ja)
DE (1) DE69506010D1 (ja)
FR (1) FR2715884B1 (ja)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102004059592B4 (de) * 2004-12-10 2014-09-04 MTU Aero Engines AG Verfahren zum Oberflächenstrahlen von Hohlräumen, insbesondere von Hohlräumen an Gasturbinen

Families Citing this family (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2743742B1 (fr) * 1996-01-24 1998-04-03 Seb Sa Procede de traitement d'une surface metallique et de fabrication d'un article culinaire
FR2753406B1 (fr) * 1996-09-16 1998-10-30 Armines Dispositif de traitement de pieces par grenaillage, plus particulierement au moyen de billes d'acier mises en mouvement par un champ ultrasonore
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
FR2791293B1 (fr) * 1999-03-23 2001-05-18 Sonats Soc Des Nouvelles Appli Dispositifs de traitement de surface par impacts
US6170308B1 (en) 1999-07-20 2001-01-09 United Technologies Corporation Method for peening the internal surface of a hollow part
US6446013B1 (en) 1999-07-20 2002-09-03 United Technologies Corporation Method for determining a peening element speed limit ratio when peening the internal surface of a hollow part
FR2801322B1 (fr) * 1999-11-18 2002-02-08 Snecma Procede de grenaillage par ultrasons de surfaces annulaires de grandes dimensions sur des pieces minces
FR2812284B1 (fr) * 2000-07-28 2003-03-07 Univ Troyes Technologie Procede de mecanique de generation de nanostructures et dispositif mecanique de generation de nanostructures
AU2001284087A1 (en) * 2000-07-28 2002-02-13 The Institue Of Metal Research (I.M.R.) Mechanical method for generating nanostructures and mechanical device for generating nanostructures
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
FR2816537B1 (fr) * 2000-11-16 2003-01-17 Snecma Moteurs Procede et installation de grenaillage par ultrasons des alveoles annulaires d'attache d'aubes sur un rotor
FR2816538B1 (fr) * 2000-11-16 2003-01-17 Snecma Moteurs Procede pour augmenter la duree de vie des attaches d'aubes sur un rotor
FR2816536B1 (fr) * 2000-11-16 2003-01-17 Snecma Moteurs Procede et dispositif de grenaillage par ultrasons des alveoles "axiales" d'attache des aubes sur un rotor
DE102004029546A1 (de) * 2004-06-19 2006-01-05 Mtu Aero Engines Gmbh Verfahren und Vorrichtung zum Oberflächenstrahlen von Gasturbinenschaufeln im Bereich ihrer Schaufelfüße
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
JP4892722B2 (ja) * 2006-01-26 2012-03-07 国立大学法人東北大学 コーティング装置とその処理方法
DE102006008210A1 (de) * 2006-02-22 2007-08-23 Mtu Aero Engines Gmbh Strahlkammer zum Oberflächenstrahlen, insbesondere zum Ultraschall-Kugelstrahlen von Gasturbinen-Bauteilen
FR2908678B1 (fr) * 2007-11-27 2010-03-12 Sonats Soc Des Nouvelles Appli Procede de grenaillage d'un percage
RU2451591C2 (ru) * 2010-08-09 2012-05-27 Государственное образовательное учреждение высшего профессионального образования "Санкт-Петербургский государственный горный институт имени Г.В. Плеханова (технический университет)" Способ поверхностного упрочнения стальных футеровок шаровых мельниц
RU2547068C2 (ru) * 2013-08-27 2015-04-10 Открытое акционерное общество "Михайловский ГОК" Способ упрочнения поверхностей стальных футеровочных плит шаровых барабанных мельниц
US9670561B2 (en) * 2014-04-11 2017-06-06 City University Of Hong Kong Apparatus and a method for surface processing a metallic structure
CN104002247A (zh) * 2014-05-14 2014-08-27 含山县众力铸造有限公司 一种抛丸清理机用打磨球喷射腔体
JP6592355B2 (ja) * 2015-01-30 2019-10-16 株式会社荏原製作所 連結機構および基板研磨装置
US9889539B1 (en) 2017-08-18 2018-02-13 General Electric Company Converting residual surface stress in internal opening of additively manufactured component
CN110629012B (zh) * 2018-06-25 2021-05-07 南京理工大学 一种在金属中实现超高应变速率塑性变形强化的方法
CN111112395B (zh) * 2020-01-03 2022-03-04 中国航空制造技术研究院 用于获取双曲率壁板的预弯工装及喷丸成形工艺

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU456704A1 (ru) * 1971-11-29 1975-01-15 Предприятие П/Я Г-4561 Способ поверхностного упрочнени
SU608564A1 (ru) * 1974-08-19 1978-05-30 Stebelkov Igor A Ультразвуковое устройство дл упрочнени деталей
SU1521564A1 (ru) * 1986-12-26 1989-11-15 Производственное объединение "Ленинградский завод турбинных лопаток" им.50-летия СССР Способ упрочнени поверхности
SU1435627A1 (ru) * 1987-04-06 1988-11-07 Кузнецкий металлургический комбинат им.В.И.Ленина Способ упрочнени стальных изделий
DE3917380A1 (de) * 1988-06-23 1989-12-28 Asea Brown Boveri Verfahren zum kaltverformen der oberflaechenzone eines werkstuecks und zum einbringen von druckeigenspannungen
US5085747A (en) * 1989-05-19 1992-02-04 Akio Nikano Ultrasonic machining method
SU1765207A1 (ru) * 1991-01-10 1992-09-30 Центральный научно-исследовательский технологический институт Способ упрочнени поверхности металлических изделий
CA2035702C (en) * 1991-02-05 1996-10-01 Mohan Vijay Ultrasonically generated cavitating or interrupted jet
FR2689431B1 (fr) * 1992-04-06 1995-10-20 Teknoson Procede et dispositif notamment de durcissement par ultrasons de pieces metalliques.

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102004059592B4 (de) * 2004-12-10 2014-09-04 MTU Aero Engines AG Verfahren zum Oberflächenstrahlen von Hohlräumen, insbesondere von Hohlräumen an Gasturbinen

Also Published As

Publication number Publication date
US5509286A (en) 1996-04-23
DE69506010D1 (de) 1998-12-24
EP0666142A1 (fr) 1995-08-09
FR2715884B1 (fr) 1996-04-12
JPH07224606A (ja) 1995-08-22
FR2715884A1 (fr) 1995-08-11

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