[go: up one dir, main page]

WO1998005948A1 - Procede et dispositif pour verifier la structure de refroidissement interne d'une pale de turbine, notamment de turbines a gaz stationnaires - Google Patents

Procede et dispositif pour verifier la structure de refroidissement interne d'une pale de turbine, notamment de turbines a gaz stationnaires Download PDF

Info

Publication number
WO1998005948A1
WO1998005948A1 PCT/DE1997/001614 DE9701614W WO9805948A1 WO 1998005948 A1 WO1998005948 A1 WO 1998005948A1 DE 9701614 W DE9701614 W DE 9701614W WO 9805948 A1 WO9805948 A1 WO 9805948A1
Authority
WO
WIPO (PCT)
Prior art keywords
turbine blade
hot air
thermographic image
image
cooling structure
Prior art date
Application number
PCT/DE1997/001614
Other languages
German (de)
English (en)
Inventor
Erich Becker
Annett Sperling
Original Assignee
Siemens Aktiengesellschaft
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
Priority claimed from DE19720461A external-priority patent/DE19720461A1/de
Application filed by Siemens Aktiengesellschaft filed Critical Siemens Aktiengesellschaft
Publication of WO1998005948A1 publication Critical patent/WO1998005948A1/fr

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N25/00—Investigating or analyzing materials by the use of thermal means
    • G01N25/72—Investigating presence of flaws
    • 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
    • F05B2200/00—Mathematical features
    • F05B2200/10—Basic functions
    • F05B2200/12—Subtraction

Definitions

  • the invention relates to a method for checking the internal cooling structure of turbine blades, in particular of stationary gas turbines.
  • DE 35 33 186 AI describes a method for cooling hole testing, in particular for testing cooling channels in turbine blades of gas turbine engines.
  • a heated gas is continuously pressed into the cooling channels of a gas turbine blade.
  • thermal images of the cooling channel openings on the surfaces of the turbine blades are recorded in a time-resolved manner.
  • the cooling channels are checked in particular by recording thermal images of the cooling channel openings that change over time and thermal images of different ones
  • Cooling channel openings are compared.
  • the method is based on the fact that the channels are heated by the continuously flowing gas and act as black body cavity radiators.
  • US Pat. No. 3,566,669 describes how wall thicknesses of cooling ducts in a turbine blade can be determined by means of a thermography measurement.
  • the turbine blade to be tested and a reference body which has different, known wall thicknesses, are connected in parallel to a switchable fluid source.
  • the turbine blade and reference body are initially kept at the same, defined temperature.
  • a fluid which has a temperature deviating from the temperature of the turbine blade or of the reference body is then passed in a pulse-like manner both into the cooling duct of the turbine blade to be tested and into the reference body.
  • the thermal radiation emitted by the turbine blade and the thermal radiation emitted by the reference body are recorded by means of an infrared scanner.
  • a comparison of the temperature profile on the turbine blade with the temperature profile of the reference body can be used to determine the known
  • Wall thicknesses of the reference body can be concluded on the wall thicknesses of the cooling channels of the turbine blade to be tested.
  • the cooling structure of a turbine blade to be tested is gas feedable. In a warm-up cycle, hot gas is injected into the
  • Headed cooling structure In a subsequent cooling cycle, cold gas is led into the cooling structure of the turbine blade. With the help of an infrared radiometer, the warm-up and cool-down cycle and the associated changes in the radiation of heat radiation from the turbine blade are recorded. Defects in the cooling structure can be found by comparing this picture with a picture of a reference blade.
  • the invention has for its object to provide a method for checking the internal cooling structure of turbine blades, which is based on a thermography measurement and enables a particularly good evaluation of such a thermography measurement. Another object of the invention is to provide a corresponding device.
  • this object is achieved by specifying a method for checking the internal cooling structure of a turbine blade, in particular a turbine blade for a stationary gas turbine, in which a) an output thermographic image of the turbine blade to be tested is recorded by means of a first infrared camera, b) the turbine blade to be tested briefly heated by blowing hot air into its cooling structure, c) at least one thermal image of the turbine blade thus heated is recorded by a second infrared camera, and d) a difference image is created from this at least one thermographic image and the initial thermographic image. Difference images can be used to quickly and reliably identify deviations and errors in the cooling system.
  • Such a difference image can be created, for example, by storing the output thermographic image and the thermographic image or the thermographic images of the heated turbine blade in the same way in the form of a raster having a plurality of raster units, and then subtracting them from one another by forming the difference from two equivalent raster units.
  • the intensities occurring there in each case can be one in the raster units
  • Thermographic image e.g. stored as a number so that the subtraction can be a simple mathematical subtraction of two numbers.
  • the difference image the temperature difference on the turbine blade surface produced by the heating is worked out in relation to the heat radiation base, which is always present, so that the thermography measurement can be better evaluated by emphasizing the heated cooling structure.
  • the first and second infrared cameras do not necessarily have to be different infrared cameras, that is to say that the first and second infrared cameras can also be one and the same infrared camera.
  • the turbine blade is preferably blackened before the starting thermographic image is taken.
  • Blackening produces an essentially uniform thermal radiation image of the turbine blade surface. Changes in the thermal radiation image due to a brief heating of the turbine blade by blowing hot air into its cooling structure, as can be seen in a thermographic image, can thus be observed more clearly. This has a further improvement of the evaluability of the thermography measurement. Blackening is preferably achieved by spraying black paint onto the turbine blade surface. This black color is preferably removed again, preferably by ultrasonic cleaning, after the test has taken place.
  • Hot air is preferably blown in at a temperature of up to 280.degree. Hot air is more preferably blown in over a period of 0.5 to 5 seconds, preferably 0.5 seconds. More preferably, the at least one thermographic image is recorded in a minimum temperature range from 0 ° C. to 200 ° C. with a temperature resolution of at least 0.05 ° C. The at least one thermographic image is preferably recorded with a local resolution of at least 0.4 mm, preferably at least 0.3 mm. A plurality of thermographic images with a recording frequency of at least 25 Hz are preferably recorded in succession.
  • another object is to provide a method for checking the internal cooling structure of a turbine blade, in particular a turbine blade for a stationary gas turbine, in which a) the turbine blade to be tested is blackened, b) the turbine blade to be tested by blowing hot air into it
  • the cooling structure is briefly heated and c) at least one thermographic image of the turbine blade heated in this way is recorded by an infrared camera.
  • the object directed to a device is achieved by a device for performing the method described above, the following being provided:
  • a computer-aided control unit for controlling the device components and the measurement sequence
  • a hot air reservoir which can be briefly connected to the turbine blade to be tested via a supply line
  • thermography camera for recording a thermographic image of the heated turbine blade
  • thermographic image A computer-aided evaluation and display unit for creating a differential image from an output thermographic image and the thermographic image of the heated turbine blade.
  • the hot air reservoir is preferably a hot air tank of preferably about 100 liters volume with a hot air temperature of up to 280 ° C.
  • the hot air reservoir more preferably has a pressure of approximately 6 bar.
  • thermography test stand 1 is a schematic perspective view of a thermography test stand
  • 2 shows a flow diagram to illustrate the functional flow during the functional check of a turbine blade and the linking of the functional units used
  • Fig. 3 is a sectional view of a turbine blade of a stationary gas turbine
  • FIG. 4 shows a section along the section line IV-IV according to FIG. 3.
  • thermography test stand shown in FIG. 1 has a flash lamp unit 1, an infrared thermography camera 2, a test part holder 3 and a control unit 4.
  • the entire test bench is housed in a chamber 5, which is air-conditioned via fans 6.
  • test stand components roughly outlined above are used to carry out a pulse video thermography process.
  • test stand In order to make the test stand suitable for a transmission thermographic measurement method, as is used in the case of the present invention, it also has a hot air tank 7 and a cold air tank 8, which can be briefly connected to the test part receptacle 3 via a feed line 9 are.
  • Capacitor blocks 10 are provided for the energy supply of the flash lamp unit.
  • a temperature control device 11 for the test bench is also indicated schematically.
  • the flash lamp unit 1 has four flash lamps 13 arranged in a square and suspended from a frame 12, each of which emits a light energy of up to 6.4 kJ per light flash emitted.
  • the pulse duration of the flashes is 5 milliseconds.
  • the frame 12 of the flash lamp unit 1 can be displaced transversely to the shooting direction A of the camera 2 on a guide 14 in order to be able to carry out the transmission test.
  • the infrared thermography camera 2 operates in a temperature range from 0 ° C. to 200 ° C. with a resolution of 0.05 ° C. It is mounted on a cross slide-like manipulator 16 with which the camera 2 along the three spatial axes x, y and z in FIG. 1 can be maneuvered via the control unit 4. Together with the arrangement of the test part receptacle 3 on a turntable 17, the camera 2 and the turbine blade 15 to be tested can be automatically positioned relative to one another via the control unit 4.
  • This control unit 4 is a first one
  • Computer of the overall system which also carries out the temperature and voltage regulation and controls the triggering of the camera 2 and the flash lamp unit 1.
  • the personal computer of the control unit 4 is therefore the actual control computer for the system components.
  • thermography camera 2 has an infrared detector with a resolution of 768 x 600 lines, which has a local resolution of approximately 0.3 mm when the thermographic image of the test part is recorded leads.
  • the recording frequency frequency is 25 Hz, so it can be every 40 milliseconds
  • Thermographic image of the test part 15 are recorded. In total, for example, 30 pictures are taken at the specified time interval, which leads to a measuring time of 1.2 seconds.
  • the camera 2 can also operate in a line scan mode, that is, scan an object line by line, which is particularly advantageous for the detection of fast processes.
  • thermographic camera 2 is then used to create an initial thermographic image of the turbine blade 15, which has not yet been heated, and is stored by means of a personal computer 19 (see FIG. 2B).
  • the cooling structure 27 of the turbine blade 15 is then briefly subjected to hot air from the hot air tank 7, after which the time course of the cooling of the turbine blade 15 is recorded with the infrared thermography camera 2 by creating thermographic images.
  • thermographic image is subtracted from the thermographic images thus created by means of the personal computer 19. From the difference images obtained in this way, the cooling structure 27 and an error that may occur in it can be recognized particularly well.
  • a coupling adapter 18 is provided for coupling the turbine blade 15 to the hot air supply line 9. It can also be seen from FIG. 2B that the control unit 4
  • Personal computer 19 with color monitor 20, color printer 21 and external data storage 22 belongs.
  • the personal computer 19 also serves to enter the test and control parameters which are transferred to the control computer 4 by the system link between the personal computer 19 and the control computer 4.
  • the control unit 4 With these input values, the control unit 4 then - as discussed - carries out the actual control, with corresponding drivers for the drives of the manipulator 16 and the turntable 17 for automatically positioning the camera 2 and the turbine blade 15 being addressed via respective control lines 23.
  • an ultrasonic bath 26 is provided in which the blackening is removed again (see FIG. 2C).
  • the turbine blade 15 is on the coupling adapter ter 18 set on the turntable 17.
  • Different coupling adapters 18 are provided for introducing the hot air into the turbine blade root for different turbine blade types.
  • the adapters are to be designed in such a way that a uniform hot air flow through the cooling channels 27 of the turbine blade 15 is achieved over the entire inlet cross section.
  • An output thermographic image of the assembled turbine blade 15 is created and stored.
  • the adapter 18 is connected via a feed line to the hot air tank 7, which holds a hot air supply of 100 liters at a temperature of up to 280 ° C. and a pressure of up to 6 bar.
  • a short-term hot air blast with a duration of up to 5 seconds is conducted through the properly positioned turbine blade 15.
  • the subsequent time profile of the temperature distribution on the surface of the turbine blade 15 to be tested, which surface is recorded by the camera 2, is recorded by the camera and by the personal computer 19 by means of a corresponding evaluation and

Landscapes

  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analyzing Materials Using Thermal Means (AREA)
  • Radiation Pyrometers (AREA)

Abstract

Ce procédé pour vérifier la structure de refroidissement interne (27) d'une pale de turbine (15), notamment d'une turbine à gaz stationnaire, consiste à réaliser une image thermographique initiale de la pale de turbine (15), puis à chauffer pendant un bref laps de temps la pale de turbine (15) par injection d'air chaud dans la structure de refroidissement (27). Ensuite, l'image thermographique initiale est soustraite de chacune des images thermographiques de la pale de turbine (15) réalisées pendant la période de chauffage.
PCT/DE1997/001614 1996-07-31 1997-07-30 Procede et dispositif pour verifier la structure de refroidissement interne d'une pale de turbine, notamment de turbines a gaz stationnaires WO1998005948A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
DE19630987 1996-07-31
DE19630987.5 1996-07-31
DE19720461A DE19720461A1 (de) 1996-07-31 1997-05-15 Verfahren und Vorrichtung zur Überprüfung der inneren Kühlstruktur von Turbinenschaufeln, insbesondere von stationären Gasturbinen
DE19720461.9 1997-05-15

Publications (1)

Publication Number Publication Date
WO1998005948A1 true WO1998005948A1 (fr) 1998-02-12

Family

ID=26027991

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/DE1997/001614 WO1998005948A1 (fr) 1996-07-31 1997-07-30 Procede et dispositif pour verifier la structure de refroidissement interne d'une pale de turbine, notamment de turbines a gaz stationnaires

Country Status (1)

Country Link
WO (1) WO1998005948A1 (fr)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3566669A (en) * 1968-09-04 1971-03-02 Harry Parker Method and apparatus for thermally examining fluid passages in a body
EP0026673A1 (fr) * 1979-10-02 1981-04-08 VLSI Technology Research Association Procédé pour mesurer la distribution de la température sur la surface d'un spécimen et dispositif pour mettre en oeuvre ledit procédé
EP0084374A2 (fr) * 1982-01-18 1983-07-27 UTI Instruments Company Traitement numérique d'image et techniques d'affichage utilisant des déterminations d'intensités différentielles d'image
DE3616220A1 (de) * 1986-05-14 1987-11-19 Willibald Luber Verfahren zur zerstoerungsfreien auffindung von hohlstellen und feuchtigkeit in den hohlstellen in und unter belaegen und abdichtungen auf bruecken
US5444241A (en) * 1993-10-01 1995-08-22 The Regents Of The University Of California Emissivity corrected infrared method for imaging anomalous structural heat flows

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3566669A (en) * 1968-09-04 1971-03-02 Harry Parker Method and apparatus for thermally examining fluid passages in a body
EP0026673A1 (fr) * 1979-10-02 1981-04-08 VLSI Technology Research Association Procédé pour mesurer la distribution de la température sur la surface d'un spécimen et dispositif pour mettre en oeuvre ledit procédé
EP0084374A2 (fr) * 1982-01-18 1983-07-27 UTI Instruments Company Traitement numérique d'image et techniques d'affichage utilisant des déterminations d'intensités différentielles d'image
DE3616220A1 (de) * 1986-05-14 1987-11-19 Willibald Luber Verfahren zur zerstoerungsfreien auffindung von hohlstellen und feuchtigkeit in den hohlstellen in und unter belaegen und abdichtungen auf bruecken
US5444241A (en) * 1993-10-01 1995-08-22 The Regents Of The University Of California Emissivity corrected infrared method for imaging anomalous structural heat flows

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
K. DING: "TEST OF JET ENGINE TURBINE BLADES BY THERMOGRAPHY", OPTICAL ENGINEERING, vol. 24, no. 6, 1985, BELLINGHAM, US, pages 1055 - 1059, XP002045762 *

Similar Documents

Publication Publication Date Title
DE19720461A1 (de) Verfahren und Vorrichtung zur Überprüfung der inneren Kühlstruktur von Turbinenschaufeln, insbesondere von stationären Gasturbinen
DE69804870T2 (de) Verfahren zum Bohren mittels Energiestrahlen sowie zur Kontrolle von Kühlmittelöffnungen
EP0632259B1 (fr) Dispositif de détection de fuite
DE102019100820A1 (de) Verfahren und Vorrichtung zur Inspektion schwer erreichbarer Komponenten
EP1176388B1 (fr) Procédé et système de contrôle pour contrôler la qualité des couches sur un objet
WO2006131568A1 (fr) Procede et dispositif pour controler la qualite d'une surface
DE19902525A1 (de) Verfahren zur automatischen Fehlererkennung bei der Rißprüfung nach dem Farbeindringverfahren
DE102007058566B4 (de) Vorrichtung und Verfahren zur berührungslosen und zerstörungsfreien Prüfung von Bauteilen mittels Wärmeflussthermografie
WO1998005921A1 (fr) Procede pour determiner l'epaisseur de paroi d'une pale de turbine et dispositif pour mettre en oeuvre ledit procede
EP1416266A1 (fr) Procédé d' inspection de la structure de trous de passage d'un matériau
DE102018222765A1 (de) System und Verfahren zur Reinigung von Wärmetauscherrohren
DE102009039224B4 (de) Verfahren und Vorrichtung zur Erkennung von verstopften Bohrungen in einem Bauteil
DE102016203666A1 (de) Vorrichtung und verfahren zur analyse des kontaminationszustandes einer oberfläche
DE19727484A1 (de) Verfahren und Vorrichtung zum Vermessen eines aus einer Sprühdüse austretenden Sprühstrahls
WO1998005948A1 (fr) Procede et dispositif pour verifier la structure de refroidissement interne d'une pale de turbine, notamment de turbines a gaz stationnaires
DE102014003912B4 (de) Lackieranlage zum Lackieren von Fahrzeugkarosserien
DE19754129C1 (de) Vorrichtung zur Erfassung der Konturänderung von Zugproben bei verschiedenen Temperaturen
DE102004041671A1 (de) Überwachung von Spritzprozessen
DE3835981C2 (fr)
EP1666863B1 (fr) Procédé d'essai de l'étanchéité de récipients
DE102012018020B4 (de) Verfahren und Anlage zum zerstörungsfreien Prüfen von mit Abstand aufeinanderfolgenden langgestreckten linienförmigen Fügeverbindungen
DE10051169B4 (de) Handgeführte Bestrahlungseinrichtung und thermisches Bearbeitungsverfahren
EP1391691B1 (fr) Procédé de mesure du diamètre d'un trou dans une pièce à usiner.
DE102022203056A1 (de) Vorrichtung zum selektiven Materialabtrag an Strukturelementen oder Schichten, die auf Oberflächen von Substraten ausgebildet sind
DE102021115111A1 (de) Verfahren zum Detektieren eines Lecks in einem fluidführenden Element einer Wärmetauschvorrichtung

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP KR RU US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: JP

Ref document number: 1998507470

Format of ref document f/p: F

122 Ep: pct application non-entry in european phase