CN219084819U - Metal object surface defect detection device - Google Patents

Abstract

The application provides a metal object surface defect detection device, metal object surface defect detection device includes: the flexible array probe comprises a flexible circuit board, an exciting coil and at least one eddy current change sensing component; the exciting coil and the eddy current change induction component are electrically connected to the wiring of the flexible circuit board; the exciting coil is electrified with alternating current with preset frequency, and when the eddy current change induction component moves on the surface of the metal object, an induction signal is output based on eddy current generated by the metal object; the data acquisition circuit is connected with the flexible circuit board and used for acquiring the induction signals output by the eddy current change induction component; the signal transmission circuit is connected with the data acquisition circuit and used for transmitting the induction signals; the induction signal characterizes the defect condition of the surface of the metal object. The application provides a device for detecting surface defects of a metal object by adopting a flexible array eddy current testing probe.

Description

Metal object surface defect detection device

Technical Field

The application belongs to the technical field of defect detection, relates to a defect detection device, and particularly relates to a metal object surface defect detection device.

Background

In the production and life of people, metal products are common, for example, different metals can be manufactured into various containers. Aiming at the defects of cracks, corrosion and the like on the surface of a metal object, especially on the inner surface, the safety and the reliability of people in use are sometimes even affected. In order to detect defects on the surface of a metal object, possible detection methods are: visual inspection, magnetic particle inspection, ultrasonic inspection, and the like.

However, some existing detection methods are greatly affected by external environment, some detection methods have pollution, some detection methods only can detect partial defects, and large-area detection is difficult to realize.

Disclosure of Invention

The present utility model provides a device for detecting surface defects of a metal object, which is used for solving the problem of how to provide a simple and reliable method for detecting surface defects of a metal object.

A first aspect of the embodiments of the present application provides a metal object surface defect detection device, including: the flexible array probe comprises a flexible circuit board, an exciting coil and at least one eddy current change sensing component; the exciting coil and the eddy current change induction component are electrically connected to the wiring of the flexible circuit board; the exciting coil is electrified with alternating current with preset frequency, and when the eddy current change induction component moves on the surface of the metal object, an induction signal is output based on eddy current generated by the metal object; the data acquisition circuit is connected with the flexible circuit board and used for acquiring the induction signals output by the eddy current change induction component; the signal transmission circuit is connected with the data acquisition circuit and used for transmitting the induction signals; the induction signal characterizes the defect condition of the surface of the metal object.

In one embodiment of the first aspect, the metal object surface defect detection device further includes: the signal processing circuit is respectively connected with the data acquisition circuit and the signal transmission circuit, and is used for amplifying and filtering the induction signals acquired by the data acquisition circuit and then transmitting the processed induction signals through the signal transmission circuit.

In one embodiment of the first aspect, the metal object surface is a curved surface; the flexible circuit board is bent and attached to the surface of the metal object.

In one embodiment of the first aspect, the metal object surface defect detection device further includes: an elastic support structure;

the elastic supporting structure is movably connected with the flexible circuit board, and the flexible circuit board is pressed and attached to the surface of the metal object.

In one embodiment of the first aspect, the metal object surface defect detection device further includes: a rotation shaft;

the rotating shaft is fixedly connected with at least one elastic supporting structure and drives at least one elastic supporting structure to rotate.

In an implementation manner of the first aspect, the elastic supporting structure drives the flexible array probe to rotate, and a moving track of the flexible array probe includes: scanning a first preset angle, advancing a first preset distance along the axial direction of the surface of the metal object, then reversely scanning a second preset angle, and advancing a second preset distance along the axial direction of the surface of the metal object, so that the metal object moves circularly.

In one embodiment of the first aspect, the metal object surface is a cylindrical hollow curved surface; the elastic support structure comprises a first support structure, a second support structure and a third support structure; the first support structure, the second support structure and one end of the third support structure are all connected with the rotating shaft and distributed in a star shape, and the included angle between the first support structure and the second support structure is 120 degrees.

In one embodiment of the first aspect, the metal object surface defect detection device further includes: a multi-way gate circuit; the multi-path gate circuit is connected with at least one eddy current change sensing component, and sensing signals output by different eddy current change sensing components are communicated to the data acquisition circuit in a time-sharing mode.

In one embodiment of the first aspect, the metal object surface defect detection device further includes: a signal analysis circuit; the signal analysis circuit is connected with the signal transmission circuit, detects a fundamental frequency signal corresponding to the excitation frequency of the excitation coil from the induction signal, and analyzes the defect condition of the surface of the metal object according to the fundamental frequency signal.

In one embodiment of the first aspect, the flexible array probe and the data acquisition circuit are connected by a connector or a flexible integral connection.

As described above, the metal object surface defect detection device has the following beneficial effects:

the application provides a defect detection mode that adopts flexible array vortex detection probe, especially to the accurate detection problem of cylindricality container metal inside metal structure defect, under elastic support structure's effect, well laminating container curved surface inner wall detects the formation of image to the container internal surface.

The device can extensively be applicable to the pressure vessel of different diameters, can conveniently realize automated inspection, can quantitatively detect the defect according to the detected image, and this application detects fastly, and is low to container inner wall surface condition requirement.

If the device is adopted to replace the existing hydrostatic test pressure container detection method, potential safety hazards can be found in time in the early stage of defects, and the development of the defects is tracked in multiple detection, so that the service life of a container structure is estimated, the detection cost is saved, and the safety and reliability of equipment are improved.

Drawings

Fig. 1 is a schematic structural diagram of a device for detecting surface defects of a metal object according to an embodiment of the present application.

Fig. 2 is a schematic diagram illustrating movement detection of a metal object surface defect detection device according to an embodiment of the present application.

Fig. 3 is a schematic view illustrating an inner side detection of a metal curved surface of a metal object surface defect detection device according to an embodiment of the present application.

Fig. 4 is a schematic view showing the elastic support lamination of the device for detecting surface defects of a metal object according to an embodiment of the present application.

Fig. 5 is a schematic diagram of a scanning path of a device for detecting a surface defect of a metal object according to an embodiment of the present application.

Fig. 6 is a schematic structural connection diagram of a metal object surface defect detection device according to an embodiment of the present application.

Fig. 7 is a signal processing circuit diagram of a metal object surface defect detection device according to an embodiment of the present application.

Fig. 8 is a schematic diagram showing defect signals of a device for detecting defects on a surface of a metal object according to an embodiment of the present application.

Description of element reference numerals

1. Flexible array probe

11. Flexible circuit board

12. Exciting coil

13. Eddy current change sensing device

2. Data acquisition circuit

3. Signal transmission circuit

4. Elastic supporting structure

5. Rotary shaft

6. Signal processing circuit

7. Multi-way gate circuit

8. Signal analysis circuit

Detailed Description

Other advantages and effects of the present application will become apparent to those skilled in the art from the present disclosure, when the following description of the embodiments is taken in conjunction with the accompanying drawings. The present application may be embodied or carried out in other specific embodiments, and the details of the present application may be modified or changed from various points of view and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments may be combined with each other without conflict.

It should be noted that, the illustrations provided in the following embodiments merely illustrate the basic concepts of the application by way of illustration, and only the components related to the application are shown in the drawings and are not drawn according to the number, shape and size of the components in actual implementation, and the form, number and proportion of the components in actual implementation may be arbitrarily changed, and the layout of the components may be more complex.

The following embodiment of the application provides a metal object surface defect detection device, has solved a plurality of problems such as exist in the different detection modes receive external environment influence great, have pollute, can only detect partial defect, and be difficult to realize detection on a large scale.

The principle of the metal object surface defect detection device is described mainly by taking the surface of a metal object as a curved surface and taking the inner curved surface of a cylindrical pressure container as an example. In addition, other curved surface defect detection of various regular or irregular curved surface defects such as various columns, cones, spheres and the like or curved surface defect detection of various closed or non-closed geometric bodies are all within the protection scope of the application.

The safety of pressure vessels during application has been a concern. For example, hydrogen containers are carriers for hydrogen storage, transportation and applications, and the performance of which directly affects the safety of hydrogen energy usage. The most common hydrogen vessel is a cylindrical gas cylinder containing a metal liner. In order to ensure the safety of the pressure vessel, a hydrostatic test, an airtight test, a hydrostatic burst test, an accelerated stress rupture test, a crack tolerance test, an environmental test, a drop test, a durability test, and the like are often adopted. At present, the technical experience in the aspects of performance test, quality verification and the like of a metal gas cylinder is still in a gradual perfection process, and a mature detection method and device are not yet available.

In the long-term use process of the pressure container, defects such as corrosion, cracks, deformation and the like can be generated on the inner wall of the pressure container, so that the safety and the reliability of the container are jeopardized. Now, a hydrostatic test is used in daily tests to test whether the container is subjected to a certain water pressure exceeding the rated pressure. The method can ensure the safety of the container to a certain extent, but only can estimate whether the container can be used continuously or not, and can not quantitatively identify the hidden trouble of the defect in the container. In order to detect defects on the metal liner inside the container, possible detection methods are: visual inspection, magnetic particle inspection, ultrasonic inspection, and the like. The defects of various detection methods are as follows: visual detection results are visual, the detection speed is high, but video detection can only detect defects of surface openings, and surface stains and light sources have great influence on imaging effects. The magnetic powder detection can only be applied to ferromagnetic metal containers, and the magnetic powder is polluted, so that the automation degree is low. The ultrasonic detection has the advantages that the penetrating power is relatively strong, but the ultrasonic detection is insensitive to longitudinal cracks, and the ultrasonic detection equipment generally needs a coupling agent when working, so that the detection speed and the degree of automation are influenced.

The applicant has appreciated that the eddy current inspection is fast, low cost, low surface condition requirements, and is conducive to rapid inspection of defects. Applicants have also appreciated that spot probes have a narrow coverage area and are difficult to apply to large-area interior wall inspection of containers. The common array probe can be used for rapid imaging quantitative detection, but because the hydrogen container is of a cylindrical structure, the hydrogen container is difficult to be well attached to the curved surface of the inner surface of the hydrogen container. Thus, a metal object surface defect detection device of the present application is proposed.

Referring to fig. 1, a schematic structural diagram of a device for detecting surface defects of a metal object according to an embodiment of the disclosure is shown. The device can be applied to detection scenes of the inner defects of the metal gas cylinder and the surfaces of various metal objects suitable for being implemented by the device. The metal may be any metal material such as steel, aluminum alloy, titanium, copper, zirconium, etc. which can generate eddy current. As shown in fig. 1, the apparatus for detecting surface defects of a metal object according to the present embodiment includes: aflexible array probe 1, adata acquisition circuit 2 and a signal transmission circuit 3.

Theflexible array probe 1 comprises aflexible circuit board 11, anexcitation coil 12 and at least one eddy current variation sensing member 13. As shown in fig. 2, theexciting coil 12 and the eddy current variation sensing part 13 are electrically connected in the wiring of theflexible circuit board 11; theexciting coil 12 is supplied with alternating current of a preset frequency, and the eddy current change sensing part 13 outputs a sensing signal based on eddy current generated by the metal object when the surface of the metal object moves. Specifically, theflexible array probe 1 may be called an array sensor, which is formed by arranging a plurality of sensor units (exciting coils and sensing coils) according to a certain geometric shape, and the array sensor moves and scans on the surface of a metal sample to generate a detection image.

Thedata acquisition circuit 2 is connected with theflexible circuit board 11 and acquires the induction signals output by the eddy current change induction component 13.

The signal transmission circuit 3 is connected with thedata acquisition circuit 2 and transmits the induction signal; the induction signal characterizes the defect condition of the surface of the metal object.

Specifically, the flexible array probe detects defects based on the principle of electromagnetic induction, and in the detection process, alternating current with a certain frequency is introduced into a gated coil, and the alternating current generates an alternating magnetic field in space, so that eddy currents are induced in a conductor metal material. If there are defects in the metal conductor, etc. that cause the material to be discontinuous, the defects can affect the distribution of the induced current as the flexible array probe is scanned over the defects. Around the excitation coil, there are one or more receiving induction coils that sense changes in induced eddy currents caused by the presence of defects, thereby reflecting the presence of defects in the output signal of the flexible array probe.

In an embodiment, theflexible array probe 1 and thedata acquisition circuit 2 are connected by a connector or a flexible integrated connection. Specifically, the flexible probe and the signal processing circuit can be connected through a connector, and also can be directly made into an integrated structure by adopting a soft and hard combined plate. The flexible circuit board is arranged on the framework and plays a role of protecting a circuit in the detection process.

Fig. 3 is a schematic view illustrating an inner side detection of a metal curved surface of the device for detecting a surface defect of a metal object according to an embodiment of the present application. As shown in fig. 3, the surface of the metal object is a curved surface; for example, the detection is performed on a cylindrical sample curved surface, theflexible circuit board 11 connected with theexciting coil 12 and the eddy current change sensing component 13 is bent and attached to the surface of the metal object, namely theflexible array probe 1 is bent and attached to the surface of the metal object, and thedata acquisition circuit 2 is connected with theflexible circuit board 11.

Specifically, theflexible array probe 1 is composed of a plurality of regularly arranged coils processed on theflexible circuit board 11, and can flexibly bend and cling to the surface of an object to be detected according to the shape of the object to be detected in the detection process, so that the flexible array probe is suitable for detecting the surfaces of metal samples with different curved surfaces such as cambered surfaces and wavy surfaces and irregular planes. Wherein the plurality of regularly arranged coils comprises an excitation coil and an induction coil, in further embodiments the eddy current variation sensing part 13 may employ a magnetic field sensor in addition to the received induction coil.

Fig. 4 is a schematic diagram showing the elastic support lamination of the apparatus for detecting surface defects of a metal object according to an embodiment of the present application. As shown in fig. 4, the apparatus for detecting surface defects of a metal object further includes: and an elastic support structure 4.

The elastic supporting structure 4 is movably connected with theflexible circuit board 11, and theflexible circuit board 11 is pressed and attached to the surface of the metal object.

The metal object surface defect detection device further comprises: and arotation shaft 5.

Therotating shaft 5 is fixedly connected with at least one elastic supporting structure 4, and drives at least one elastic supporting structure 4 to rotate.

Fig. 5 is a schematic diagram showing a scanning path of a device for detecting a surface defect of a metal object according to an embodiment of the disclosure. As shown in fig. 5, the elastic support structure 4 drives theflexible array probe 1 to rotate, and the movement track of theflexible array probe 1 includes: scanning a first preset angle, advancing a first preset distance along the axial direction of the surface of the metal object, then reversely scanning a second preset angle, and advancing a second preset distance along the axial direction of the surface of the metal object, so that the metal object moves circularly.

In one embodiment, the surface of the metal object is a cylindrical hollow curved surface, such as a cylindrical pressure vessel. With continued reference to fig. 4, the resilient support structure 4 includes a first support structure, a second support structure, and a third support structure; the first support structure, the second support structure and one end of the third support structure are all connected with the rotating shaft and distributed in a star shape, and the included angle between the first support structure and the second support structure is 120 degrees.

Specifically, theflexible array probe 1 is tightly attached to the inner surface of the container under the pressure of the elastic supporting structure 4, and the probe is kept well attached to the surface of the container. The other end of the elastic support structure 4 is connected to arotation shaft 5 located at the center of the circle. For supporting therotation shaft 5, the device may comprise 2-4 elastic support structures, and correspondingly, each support structure may be provided with aflexible array probe 1, or only part of the support structures may be provided with theflexible array probe 1. Theflexible array probe 1 is driven by therotating shaft 5 to scan in the container, so as to generate a detection image.

The scanning mode can also be that a certain angle is scanned along the clockwise direction, namely a first preset angle, and then the scanning mode is advanced along the axial direction for a certain distance, namely a first preset distance; then reversely scanning a certain angle, namely a second preset angle, and then advancing a certain distance along the axial direction, namely a second preset distance. This is repeated continuously. For example, assuming a total of 3 support structures on the circumference, each 120 ° apart, the coverage length of a single probe is 10cm, the scanning pattern may be as follows: a. the three probes are driven by the rotating shaft to scan 120 degrees in the clockwise direction, and then advance by 10cm in the axial direction, c. the probes are scanned by 120 degrees in the reverse direction, d. the probes advance by 10cm in the axial direction, and the step a is repeated, so that the detection image is produced.

It should be noted that, in the present application, the first preset angle and the second preset angle preferably use the same value, and in different embodiments, different values may also be selected; in this application, the first preset distance and the second preset distance preferably have the same value, and in different embodiments, different values may also be selected.

Fig. 6 is a schematic structural connection diagram of a metal object surface defect detection device according to an embodiment of the disclosure. In various embodiments, the apparatus for detecting surface defects of a metal object further includes: a signal processing circuit 6, a multiplexer circuit 7 and a signal analysis circuit 8.

The signal processing circuit 6 is respectively connected with thedata acquisition circuit 2 and the signal transmission circuit 3, and the signal transmission circuit 3 transmits the processed induction signals after amplifying and filtering the induction signals acquired by thedata acquisition circuit 2.

The multi-path gate circuit 7 is connected with at least one eddy current change sensing component 13, and communicates sensing signals output by different eddy current change sensing components 13 to thedata acquisition circuit 2 in a time-sharing manner.

The signal analysis circuit 8 is connected to the signal transmission circuit 3, detects a fundamental frequency signal corresponding to an excitation frequency of theexcitation coil 12 from the induction signal, and analyzes a defect condition of the surface of the metal object based on the fundamental frequency signal. Specifically, after the induction signal is amplified and filtered, the signal is converted into a digital signal through an analog-to-digital converter, and then analyzed by the signal analysis circuit 8, a fundamental frequency signal corresponding to the excitation frequency is detected, and a detection image of the defect signal is generated.

In practical applications, the signal analysis circuit 8 may be disposed in an analysis device, where the analysis device includes a processor and a memory; the processor is connected with the memory, the memory is used for storing a computer program, and the processor is used for executing the computer program stored in the memory so as to analyze the digital signal of the induction signal, detect the fundamental frequency signal corresponding to the excitation frequency and further generate a detection image of the defect signal.

In addition, a motor is connected with the rotating shaft, the analysis equipment can be connected with the motor, and an operation instruction is sent when the detection starts to control the start and stop, the direction and the rotating speed of the motor so as to automatically complete the moving track of theflexible array probe 1.

Referring to fig. 7, a signal processing circuit diagram of a metal object surface defect detection device according to an embodiment of the present application is shown. As shown in fig. 7, the acquisition of signals of the flexible array probe, i.e. the array sensor, is generally based on a mode of single channel acquisition and time division multiplexing, i.e. different sensor channel unit signals OUT1 and OUT2 are input into a data acquisition circuit or data acquisition channel equipment in a time-sharing manner through a multi-channel gate circuit, weak induction signals are easily lost and interfered by noise in long-distance transmission, so that an amplifying circuit (a signal processing circuit 6) is adopted in the probe to amplify the signals before transmitting OUT signals.

Fig. 8 is a schematic diagram showing a defect signal of a device for detecting a surface defect of a metal object according to an embodiment of the disclosure. As shown in fig. 8, a final detected image formed from the induction signals output from the eddy current variation induction section 13 is shown, wherein the middle black area represents each defect signal.

The descriptions of the processes or structures corresponding to the drawings have emphasis, and the descriptions of other processes or structures may be referred to for the parts of a certain process or structure that are not described in detail.

The foregoing embodiments are merely illustrative of the principles of the present application and their effectiveness, and are not intended to limit the application. Modifications and variations may be made to the above-described embodiments by those of ordinary skill in the art without departing from the spirit and scope of the present application. Accordingly, it is intended that all equivalent modifications and variations which may be accomplished by persons skilled in the art without departing from the spirit and technical spirit of the disclosure be covered by the claims of this application.

Claims (10)

1. A metal object surface defect detection apparatus, characterized in that the metal object surface defect detection apparatus comprises:

the flexible array probe comprises a flexible circuit board, an exciting coil and at least one eddy current change sensing component; the exciting coil and the eddy current change induction component are electrically connected to the wiring of the flexible circuit board; the exciting coil is electrified with alternating current with preset frequency, and when the eddy current change induction component moves on the surface of the metal object, an induction signal is output based on eddy current generated by the metal object;

the data acquisition circuit is connected with the flexible circuit board and used for acquiring the induction signals output by the eddy current change induction component;

the signal transmission circuit is connected with the data acquisition circuit and used for transmitting the induction signals; the induction signal characterizes the defect condition of the surface of the metal object.

2. The metal object surface defect detection apparatus according to claim 1, wherein the metal object surface defect detection apparatus further comprises:

the signal processing circuit is respectively connected with the data acquisition circuit and the signal transmission circuit, and is used for amplifying and filtering the induction signals acquired by the data acquisition circuit and then transmitting the processed induction signals through the signal transmission circuit.

3. The apparatus according to claim 1, wherein the surface of the metal object is a curved surface; the flexible circuit board is bent and attached to the surface of the metal object.

4. The metal object surface defect detection apparatus according to claim 3, wherein the metal object surface defect detection apparatus further comprises: an elastic support structure;

the elastic supporting structure is movably connected with the flexible circuit board, and the flexible circuit board is pressed and attached to the surface of the metal object.

5. The apparatus for detecting a surface defect of a metal object according to claim 4, wherein the apparatus for detecting a surface defect of a metal object further comprises: a rotation shaft;

the rotating shaft is fixedly connected with at least one elastic supporting structure and drives at least one elastic supporting structure to rotate.

6. The metal object surface defect detection apparatus according to claim 5, wherein:

the elastic supporting structure drives the flexible array probe to rotate, and the moving track of the flexible array probe comprises: scanning a first preset angle, advancing a first preset distance along the axial direction of the surface of the metal object, then reversely scanning a second preset angle, and advancing a second preset distance along the axial direction of the surface of the metal object, so that the metal object moves circularly.

7. The apparatus according to claim 5, wherein the surface of the metal object is a cylindrical hollow curved surface;

the elastic support structure comprises a first support structure, a second support structure and a third support structure; the first support structure, the second support structure and one end of the third support structure are all connected with the rotating shaft and distributed in a star shape, and the included angle between the first support structure and the second support structure is 120 degrees.

8. The metal object surface defect detection apparatus according to claim 1, wherein the metal object surface defect detection apparatus further comprises: a multi-way gate circuit;

the multi-path gate circuit is connected with at least one eddy current change sensing component, and sensing signals output by different eddy current change sensing components are communicated to the data acquisition circuit in a time-sharing mode.

9. The metal object surface defect detection apparatus according to claim 1, wherein the metal object surface defect detection apparatus further comprises: a signal analysis circuit;

the signal analysis circuit is connected with the signal transmission circuit, detects a fundamental frequency signal corresponding to the excitation frequency of the excitation coil from the induction signal, and analyzes the defect condition of the surface of the metal object according to the fundamental frequency signal.

10. The metal object surface defect detection apparatus according to claim 1, wherein:

the flexible array probe is connected with the data acquisition circuit through a connector or a flexible integrated connection.

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