DE102011003471A1 - Method for performing non-destructive material testing of rotary component e.g. wheel for railway vehicle, involves detecting magnetic field induced from component by inducing eddy current into component - Google Patents

Abstract

The method involves implementing components (BT1,BT2) to be tested with a magnetic field generated by of induction coil (IS). The magnetic field induced from the component is detected by inducing eddy current into component. The detected magnetic field is evaluated in real time using evaluation unit (AE). An independent claim is included for device for performing non-destructive materials testing of rotary component.

Description

The present invention relates to a method and a device for non-destructive material testing of a rotating component in operation.

For machines and technical equipment, the provision of functionality often depends on individual components. However, these components may show cracks due to wear, fatigue, and external forces. Wear of the components can be caused by mechanical stress of the component during regular operation of the machine or the technical device. Material fatigue refers to a typically slowly progressing damage process of the material from which the device is molded and / or which comprises the device. A common cause of material fatigue of a component is z. B. a temperature fluctuation, which acts on the device.

Due to the occurrence of cracks, components may be inoperative or may no longer meet required safety standards. With regard to a safety assessment of components which have cracks, a crack analysis and a prediction of a crack behavior is necessary. Typical of crack growth is slow growth of the crack at the beginning of the crack and very rapid growth after exceeding a critical crack parameter or exceeding a critical crack parameter threshold, resulting in final breakage of the device.

Potentially affected components are identified during the design phase. In the operating phase, regular checks are carried out on these components. For this purpose, the technical systems or machines are disassembled and the affected parts exposed. These are then usually subjected to known non-destructive tests. These include ultrasonic testing, dye penetrant testing, radiation, magnetic particle inspection and eddy current testing. So z. In the European patent application EP 2 103 932 A1 discloses an ultrasonic system for non-destructive testing. These checks take place in a predetermined time grid and, if necessary, enable the timely replacement of a used component with new parts.

Most test methods have the disadvantage that they can not be made during the operation of the component. This means machine rest periods or even downtime for an entire system (eg production line). Downtimes for a machine or plant represent losses for the operator.

It is an object of the present invention to provide a method and a device for non-destructive material testing of a rotating component in operation.

• S1) Durchsetzen des zu prüfenden Bauteiles mit einem Magnetfeld, das von einer Induktionsspule erzeugt wird;
• S2) Erfassen von Magnetfeldern, die vom Bauteil durch darin induzierte Wirbelströme ausgehen, durch eine Sensorspule; und
• S3) Auswerten der erfassten Magnetfelder durch eine Auswerteeinheit. Das Bauteil wird während der Betriebsphase permanent überprüft, ohne dass der Betrieb unterbrochen oder eingeschränkt wird. Stillstandszeiten für eine Maschine oder eine Anlage werden vermieden. Der Wartungsaufwand technischer Systeme wird verringert. Bauteilversagen und -alterung können genauer und zuverlässiger prognostiziert werden, da die Datenerfassung und Datenauswertung permanent, systematisch und mit hoher zeitlicher Auflösung erfolgt. Bauteile können näher an ihre Alterungsgrenze heran genutzt werden und somit länger im Einsatz bleiben.

The object is achieved by a method for non-destructive material testing of a rotating component in operation, comprising the following steps:

• S1) passing through the component under test with a magnetic field generated by an induction coil;
• S2) detecting magnetic fields emanating from the component by eddy currents induced therein by a sensor coil; and
• S3) Evaluation of the detected magnetic fields by an evaluation unit. The component is permanently checked during the operating phase without interrupting or restricting operation. Downtimes for a machine or a system are avoided. The maintenance of technical systems is reduced. Component failure and aging can be more accurately and reliably predicted, as data acquisition and analysis is permanent, systematic and with high temporal resolution. Components can be used closer to their age limit and thus remain in use longer.

A first advantageous embodiment of the invention is that the magnetic fields detected by the sensor coil are stored by a transient recorder in digitized form. Thereby it is u. a. possible to carry out evaluations over a longer period of time (monitoring or observation period). Thus, z. B. also reliably define expected target signals.

A further advantageous embodiment of the invention is that the evaluation unit evaluates the detected magnetic fields in real time. As a result, it is possible to react immediately and situation-dependent to recognized or incipient cracks or material fatigue phenomena on a component. For example, by scheduling a maintenance interval or by changing the load on the machine concerned.

A further advantageous embodiment of the invention is that an alarm is triggered by the evaluation unit when an abnormality is detected in the detected magnetic fields. By informing the operating personnel (eg system operator), this can be immediately and situation-dependent on detected or incipient cracks or Material fatigue phenomena react on a component and initiate appropriate action. It can, for. B. a maintenance use for closer examination or replacement of the component to be made.

• c1) Erkennung von Umdrehungszyklen;
• c2) Auftragen der Sensorsignale über den Umdrehungszyklus und Abspeichern jeder einzelnen Umdrehung oder einer Auswahl davon zur Erzeugung von Umdrehungssignalen;
• c3) Vergleichen der Umdrehungssignale;
• c4) Erstellen und Aktualisieren von durchschnittlichen bzw. typischen Umdrehungssignalen. Durch einen computerunterstützten Merkmals- oder Mustervergleich (z. B. durch Methoden der statistischen und/oder strukturellen Mustererkennung) des erwarteten Sollsignals (Gutfall) mit dem erhaltenen Istsignal werden Veränderungen oder Abnormalitäten am Istsignal erkannt.

A further advantageous embodiment of the invention is that the step S3) "evaluation of the detected magnetic fields by an evaluation unit" comprises the following steps:

• c1) Recognition of revolution cycles;
• c2) applying the sensor signals over the revolution cycle and storing each revolution or a selection thereof to generate revolution signals;
• c3) comparing the revolution signals;
• c4) Create and update average or typical revolution signals. By means of a computer-assisted feature or pattern comparison (eg by methods of statistical and / or structural pattern recognition) of the expected desired signal (good case) with the actual signal obtained, changes or abnormalities in the actual signal are detected.

• c1) Fortlaufende Umwandlung des Zeitsignals in ein Frequenzspektrum, z. B. mittels eines FFT-Algorithmus (Fast Fourier Transformation),
• c2) Vergleichen der Signalspektren,
• c3) Erstellen und Aktualisieren von durchschnittlichen bzw. typischen Signalspektren. Durch einen computerunterstützten Merkmals- oder Mustervergleich (z. B. durch Methoden der statistischen und/oder strukturellen Mustererkennung) des erwarteten Sollspektrums (Gutfall) mit dem erhaltenen Istspektrum werden Veränderungen oder Abnormalitäten am Istspektrum erkannt.

A further advantageous embodiment of the invention is that the step S3) "evaluation of the detected magnetic fields by an evaluation unit" comprises the following steps:

• c1) Continuous conversion of the time signal into a frequency spectrum, e.g. B. by means of an FFT algorithm (Fast Fourier Transformation),
• c2) comparing the signal spectra,
• c3) Creating and updating average or typical signal spectra. By means of a computer-assisted feature or pattern comparison (eg by methods of statistical and / or structural pattern recognition) of the expected target spectrum (Gutfall) with the obtained actual spectrum, changes or abnormalities in the actual spectrum are recognized.

A further advantageous embodiment of the invention is the triggering of alarms via a data interface and / or an operator interface in the case of short-term deviations of the current revolution signal from a typical revolution signal or the current signal spectrum from a typical signal spectrum. Alarm messages can be recorded by machine and / or forwarded to z. For example, a corresponding message (eg text or picture message) can be displayed on a monitor for the operating personnel at a control station.

A further advantageous embodiment of the invention is the triggering of messages via the data interface and / or the user interface in the case of the approach of the current rotation signal to predetermined reference signals or signal spectra, which indicate a reaching the component life or on a critical component aging. As a result, it is possible to react even before the occurrence of a damage event (eg component breakage), for example B. by replacing the affected component before the break actually occurs.

A further advantageous embodiment of the invention is that a sensor coil is also used as an induction coil or an induction coil as a sensor coil. This allows greater flexibility, since several coils can be used both as an induction coil and as a sensor coil. In addition, so the number of coils used can be minimized. In extreme cases, the device contains only a single coil.

A further advantageous embodiment of the invention lies in a device for carrying out the method according to the invention for non-destructive material testing of a rotating component in operation. The device contains one or more coils which pass through the component with a magnetic field and an alternating current source for driving these coils. Furthermore, it contains one or more sensor coils for detecting the magnetic fields emanating from the component by eddy currents induced therein. A transient recorder stores the signals of the sensor coils in digitized form. Furthermore, an evaluation unit is provided which evaluates the signals stored in the memory using real-time algorithms. Optionally, the device includes a data interface to an external data network and / or an operator interface for operating personnel. The device is controlled by a computer (eg PC, laptop) with input (eg keyboard, mouse) and output means (eg printer, screen) and corresponding software for controlling the device and for evaluating the device signals.

A further advantageous embodiment of the invention is that the device comprises a signal splitter which separates the eddy currents induced in the component from an exciter signal and forwards them to the transient recorder. A variant of the device results from the simultaneous use of one or more coils both as an induction coil and as a sensor coil. For this purpose, the device includes a signal splitter which separates the eddy currents induced in the component from the exciter signal and forwards them to the transient recorder.

An embodiment of the invention is illustrated in the drawing and will be explained below.

Showing:

1 a first embodiment of the device according to the invention,

2 A second embodiment of the inventive device, and

3 an exemplary flowchart for carrying out the method according to the invention.

According to the invention, an apparatus and a method for in-use checking of rotating components are proposed.

1 shows a first embodiment of the device V1 according to the invention. The component BT1 is permanently checked during the operating phase without the operation being interrupted or restricted. The device V1 contains one or more induction coils IS which pass through the component BT1 with a magnetic field and one or more AC sources WSQ for driving these induction coils IS. Furthermore, the device V1 contains one or more sensor coils SS for detecting the magnetic fields emanating from the component BT1 by eddy currents induced therein. A transient recorder TR stores the signals of the sensor coils SS in digitized form. Furthermore, an evaluation unit AE is present, which evaluates the signals stored in the memory M1 (for detected revolution signals) using real-time algorithms (eg algorithms for pattern or feature recognition). The evaluation takes place by a comparison of the detected revolution signals with reference signals stored in the memory M2. Finally, the device V1 includes a data interface DS to an external data network (eg Internet, Intranet or LAN) and / or an operator interface BE (eg a control station) for operating personnel.

• 1. Erkennung von Umdrehungszyklen.
• 2. Auftragen der Sensorsignale über den Umdrehungszyklus und Abspeichern jeder einzelnen Umdrehung oder einer Auswahl davon (”Umdrehungssignal”).
• 3. Vergleich von Umdrehungssignalen.
• 4. Erstellung und Aktualisierung von durchschnittlichen bzw. typischen Umdrehungssignalen.
• 5. Auslösen von Alarmen über die Datenschnittstelle DS und/oder die Bedienschnittstelle BE im Falle kurzfristiger Abweichungen des aktuellen Umdrehungssignals vom typischen Signal (Referenzsignal).
• 6. Auslösen von Meldungen über die Datenschnittstelle DS und/oder die Bedienschnittstelle BE im Falle der Annäherung des aktuellen Umdrehungssignals an zuvor festgelegte Referenzsignale, die auf ein Erreichen der Bauteillebensdauer bzw. auf eine kritische Bauteilalterung hindeuten. Es kann dann ein Instandhaltungseinsatz zur näheren Untersuchung oder zum Austausch des Bauteils BT1 vorgenommen werden. Eine Variante der Vorrichtung V1 ergibt sich durch die gleichzeitige Nutzung einer oder mehrerer Spulen sowohl als Induktions- als auch als Sensorspule. Dazu enthält die Vorrichtung V1 eine Signalweiche, die die im Bauteil BT1 induzierten Wirbelströme vom Erregersignal trennt und an den Transientenrekorder TR weiterleitet.

The permanently running algorithm of the evaluation unit AE comprises the following functions:

• 1. Recognition of revolution cycles.
• 2. Apply the sensor signals over the revolution cycle and store each revolution or a selection thereof ("revolution signal").
• 3. Comparison of revolution signals.
• 4. Creation and update of average or typical revolution signals.
• 5. Triggering of alarms via the data interface DS and / or the operator interface BE in the case of short-term deviations of the current revolution signal from the typical signal (reference signal).
• 6. Triggering of messages via the data interface DS and / or the operating interface BE in the case of the approach of the current revolution signal to predetermined reference signals, which indicate the reaching of the component life or a critical component aging. It can then be made a maintenance operation for closer examination or replacement of the component BT1. A variant of the device V1 results from the simultaneous use of one or more coils both as an induction coil and as a sensor coil. For this purpose, the device V1 contains a signal switch, which separates the eddy currents induced in the component BT1 from the exciter signal and forwards them to the transient recorder TR.

The inventive device and the inventive method can, for. B. be used for gears in large gearboxes or wheels in railway vehicles.

• – Der Wartungsaufwand technischer Systeme wird verringert, da Wartungseinsätze und die damit verbundenen Stillstände vermieden werden.
• – Bauteilversagen und -alterung können genauer und zuverlässiger prognostiziert werden, da die Datenerfassung und Datenauswertung permanent, systematisch und mit hoher zeitlicher Auflösung erfolgt.
• – Bauteile können näher an ihre Alterungsgrenze heran genutzt werden und somit länger im Einsatz bleiben.

Advantages of the device or the method according to the invention:

• - The maintenance of technical systems is reduced, since maintenance operations and the associated shutdowns are avoided.
• - Component failure and aging can be predicted more accurately and reliably as data acquisition and analysis is permanent, systematic and with high temporal resolution.
• - Components can be used closer to their age limit and thus remain in use longer.

2 shows a second embodiment of the device according to the invention. In 2 It is shown that the device V2 according to the invention is advantageously used computer-assisted. The device V2 monitors a component BT2. In particular, the analysis and evaluation algorithms (algorithms for pattern and feature recognition) are executed on a computer C by appropriate software programs. The computer C can also serve as part of a control room and on the screen M alarm messages for the operator can be issued. The device V2 is z. B. via a data interface (wired or wireless (wireless)) connected to the control room. The computer C can z. As a personal computer (PC), a workstation, an industrial controller (PLC) or a laptop.

• – S1) Durchsetzen des zu prüfenden Bauteiles mit einem Magnetfeld, das von einer Induktionsspule erzeugt wird;
• – S2) Erfassen von Magnetfeldern, die vom Bauteil durch darin induzierte Wirbelströme ausgehen, durch eine Sensorspule; und
• – S3) Auswerten der erfassten Magnetfelder durch eine Auswerteeinheit. Der Schritt S3 umfasst folgende Unterschritte:
• – c1) Erkennung von Umdrehungszyklen;
• – c2) Auftragen der Sensorsignale über den Umdrehungszyklus und Abspeichern jeder einzelnen Umdrehung oder einer Auswahl davon zur Erzeugung von Umdrehungssignalen;
• – c3) Vergleichen der Umdrehungssignale;
• – c4) Erstellen und Aktualisieren von durchschnittlichen bzw. typischen Umdrehungssignalen.

3 shows an exemplary flowchart for carrying out the method according to the invention. The non-destructive material testing method of an in-service rotating component, comprising the following steps:

• - S1) passing through the component to be tested with a magnetic field generated by an induction coil;
• - S2) detecting magnetic fields emanating from the component by eddy currents induced therein by a sensor coil; and
• - S3) evaluating the detected magnetic fields by an evaluation unit. The step S3 comprises the following substeps:
• - c1) detection of revolution cycles;
• C2) applying the sensor signals over the revolution cycle and storing each revolution or a selection thereof to generate revolution signals;
• - c3) comparing the revolution signals;
• - c4) Create and update average or typical revolution signals.

• – c51) Auslösen von Alarmen über eine Datenschnittstelle und/oder eine Bedienschnittstelle im Falle kurzfristiger Abweichungen des aktuellen Umdrehungssignal von einem typischen Umdrehungssignal.
• – C52) Auslösen von Meldungen über die Datenschnittstelle und/oder die Bedienschnittstelle im Falle der Annäherung des aktuellen Umdrehungssignals an zuvor festgelegte Referenzsignale, die auf ein Erreichen der Bauteillebensdauer bzw. auf eine kritische Bauteilalterung hindeuten.

Optionally, the method according to the invention may comprise the following further steps:

• - c51) triggering alarms via a data interface and / or an operator interface in the event of short-term deviations of the current revolution signal from a typical revolution signal.
• - C52) Triggering of messages via the data interface and / or the operating interface in the case of the approach of the current revolution signal to predetermined reference signals, which point to the achievement of the component life or to a critical component aging.

These steps are advantageously carried out computer-assisted (eg on a PC or an industrial controller). The evaluation unit AE is advantageously implemented as a software program.

Device and method for non-destructive material testing of a rotating component in operation The device contains u. a. one or more coils which pass through the component with a magnetic field and an alternating current source for driving these coils. Furthermore, it contains one or more sensor coils for detecting the magnetic fields emanating from the component by eddy currents induced therein. A transient recorder stores the signals of the sensor coils in digitized form. Furthermore, an evaluation unit is provided which evaluates the signals stored in the memory using real-time algorithms. Optionally, the device includes a data interface to an external data network and / or an operator interface for operating personnel.

reference numeral

• BT1, BT2

  component

  SS

  sensor coil

  IS

  induction coil

  WSQ

  AC power source

  TR

  transient

  M1, M2

  Storage

  AE

  evaluation

  DS

  Data Interface

  BE

  operating unit

  V1, V2

  contraption

  M

  monitor

  C

  computer

  S1-S3

  step

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 2103932 A1 [0004]

Claims (11)

A nondestructive material testing method of an operating rotating component (BT1, BT2) comprising the following steps: S1) passing through the component under test (BT1, BT2) with a magnetic field generated by an induction coil (IS); S2) detecting magnetic fields emanating from the component (BT1, BT2) by eddy currents induced therein by a sensor coil; and S3) evaluating the detected magnetic fields by an evaluation unit (AE). Method according to Claim 1, characterized in that the magnetic fields detected by the sensor coil (SS) are stored in digitized form by a transient recorder (TR). A method according to claim 1 or 2, characterized in that the evaluation unit (AE) evaluates the detected magnetic fields in real time. Method according to one of the preceding claims, characterized in that an alarm is triggered by the evaluation unit (AE) if an abnormality is detected in the detected magnetic fields. Method according to one of the preceding claims, characterized in that the step S3) "evaluating the detected magnetic fields by an evaluation unit" comprises the following steps: c1) Recognition of revolution cycles; c2) applying the sensor signals over the revolution cycle and storing each revolution or a selection thereof to generate revolution signals; c3) comparing the revolution signals; c4) Create and update average or typical revolution signals. Method according to one of claims 1 to 4, characterized in that the step S3) "evaluating the detected magnetic fields by an evaluation unit" comprises the following steps: c1) continuous conversion of the time signal into a frequency spectrum, c2) comparing the signal spectra, c3) Creating and updating average or typical signal spectra. The method of claim 5 or 6, further comprising the following step: c51) triggering alerts via a data interface and / or an operator interface in the event of short-term deviations of the current revolution signal from a typical revolution signal or the current signal spectrum from a typical signal spectrum. The method of claim 5, 6 or 7, further comprising the following step: C52) triggering of messages via the data interface (DS) and / or the operator interface (BE) in the case of the approach of the current revolution signal to predetermined reference signals or signal spectra, which indicate the achievement of the component life or a critical component aging. Method according to one of the preceding claims, characterized in that a sensor coil (SS) is also used as an induction coil (IS) or an induction coil (IS) as a sensor coil (SS). Device (V1, V2) for carrying out the method according to one of the preceding claims 1 to 9. Apparatus according to claim 10, characterized in that the device (V1, V2) comprises a signal switch, which separates the induced eddy currents in the component (BT1, BT2) from an excitation signal and forwards to the transient recorder (TR).

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