KR102084194B1 - Apparatus for flaw detection for nondestructive inspection - Google Patents

Abstract

Non-destructive inspection device according to an embodiment of the present invention is a flexible (Flexible) substrate; A sensor unit provided on the substrate and having a plurality of sensors arranged thereon; A plurality of pressing members separated from each other, one end of which is in contact with the sensor and bent according to the shape of the substrate; And a fixing member having the other ends of the pressing members coupled to the lower surface.

Description

Non-destructive testing device {APPARATUS FOR FLAW DETECTION FOR NONDESTRUCTIVE INSPECTION}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flaw detector for nondestructive inspection, and more particularly, to a flaw detector for nondestructive inspection in which magnetic sensors are held in close contact with beads.

The joint surface on which welding is made is likely to be a starting point of a defect. Good and bad welding results are affected by the substrate, the electrode and all of the working conditions.

1 is a view showing an example of the bead shape and defects of the weld joint. Referring to FIG. 1, welding cracks, porosity, undercut, overlap, slag inclusion, spatter, incomplete penetration, lack of fusion, etc. Incomplete Fusion, welding defects such as fittings, craters, and underfill must be minimized during manufacturing.

However, these defects are difficult to detect with the naked eye, so they must be inspected by nondestructive examination. In particular, non-destructive inspection using electromagnetic phenomena such as leakage magnetic flux inspection and eddy current inspection has the advantage of being able to inspect at high speed.

The leak magnetic flux inspection method is a method of measuring the change of magnetic flux density occurring around a defect by a magnetic sensor after energizing or magnetizing a test piece having a welded joint. The magnetic sensor has sensitivity anisotropy on the sensor surface and has a maximum sensitivity to magnetic flux density incident vertically or horizontally. That is, even if the magnitude of the magnetic flux density is the same, the signal output value is different when the sensor surface is inclined inclinedly.

Eddy current inspection is the variation of the time-varying flux density caused by the induction current (eddy current) caused by Faraday-Lenz's law and the distortion of the induced current flow due to the presence of a defect. Is measured by magnetic sensor. Like the leaky magnetic flux inspection method, the magnetic sensor has sensitivity anisotropy on the sensor surface and has a maximum sensitivity to the magnetic flux density incident vertically or horizontally.

Both the leak magnetic flux inspection method and the eddy current inspection method require an array of magnetic sensors with higher spatial resolution to inspect smaller defects or to estimate the shape and size of the defects.

2 is a view showing an embodiment of a conventional electromagnetic non-destructive inspection device. Specifically, FIG. 2A is a product photograph of a conventional electromagnetic non-destructive testing device, and FIG. 2B is a view showing an example when the conventional electromagnetic non-destructive testing device passes through a bead. (Non-Patent Document 1)

Referring to FIG. 2, after storing sensors in individual sensor mechanisms having a spring structure, several individual sensor mechanisms are arranged adjacently, and the magnetic flux density distribution in the vicinity of the weld joint is measured while scanning along the longitudinal direction of the weld joint. do. In this structure, the sensor surface by the individual sensor mechanism located in the center of the bead of the welded joint is parallel to the contact plane of the bead, but in the inclined portion where the bead and the base material meet, the angle of the sensor plane and the contact plane of the beads is not parallel Do not. Therefore, there is a problem that the magnetic flux density is not vertically incident on the sensor surface.

In addition, there is a limit to increase the spatial resolution by narrowing the distance between the sensor and the sensor due to the volume of the individual sensor mechanism and the spring.

 http://qualitechplc.com/service-category.php?id=1cc641954099c249e0e4ef0402da3fd0364d95f0

The present invention has been invented to solve the above problems, the object is to adhere the substrate to the bead by using the pressing member having an elastic force, so that the contact surface of the bead and the contact surface of the magnetic sensor arranged on the substrate to be parallel It relates to a flaw detection apparatus for nondestructive testing.

Non-destructive inspection device according to an embodiment of the present invention is a flexible (Flexible) substrate; A sensor unit provided on the substrate and having a plurality of sensors separated from each other; Pressure members having one end contacting the sensor unit and bent in accordance with the shape of the substrate; And it may include a fixing member coupled to the other end of the pressing member on the lower surface.

The pressing member may include an elastic body having an elastic force.

The substrate may be bent to correspond to the shape of the object to be measured.

When the pressing member is bent according to the shape of the substrate, the pressing member may apply a force such that the substrate is in close contact with the surface of the object to be measured.

Non-destructive testing flaw detection apparatus according to another embodiment of the present invention may include a fixture coupled to the central portion of the lower surface of the fixing member one end in the width direction of the fixing member.

The pressing members may be coupled to the fixing member symmetrically about the fixing body.

The pressing members may be bent in the longitudinal direction of the substrate by the fixing member when the pressing members are bent in accordance with the shape of the substrate.

According to the non-destructive testing flaw detection apparatus according to an embodiment of the present invention, the flexible substrate is bent to correspond to the shape of the bead, the elastic member is in close contact with the substrate and the beads, thereby reducing the lift-off (Lift-off) Can be.

In addition, since the sensor plane of the magnetic sensors arranged on the substrate and the contact plane of the beads are parallel, there is an advantage that the magnetic flux density is perpendicular to the sensor plane of the magnetic sensors.

In addition, since the pressing member having an elastic force exerts a force to return the substrate to its original shape, there is an advantage that the substrate easily returns to the original shape without any further action, thereby increasing the life of the flaw detector.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included as part of the detailed description in order to provide a thorough understanding of the present invention, provide examples of the present invention and together with the description, describe the technical features of the present invention.
1 is a view showing an example of the bead shape and defects of the weld joint.
2 is a view showing an embodiment of a conventional electromagnetic non-destructive inspection device.
3 is a block diagram schematically illustrating a flaw detector for non-destructive testing according to an embodiment of the present invention.
4 is a view briefly illustrating a flaw detector for non-destructive testing according to an embodiment of the present invention.
5 is a view showing an embodiment of a conventional electromagnetic non-destructive inspection device.
6 is a view showing a comparative embodiment using one second pressing member.
7 is a view briefly illustrating a flaw detector for non-destructive testing according to another embodiment of the present invention.

In this specification, terms such as first and / or second are used only for the purpose of distinguishing one component from another component. That is, it is not intended to limit the components by the above terms.

Components, features, and steps that are referred to herein as "comprising" mean that such components, features, and steps exist and are intended to exclude one or more other components, features, steps, and equivalents. This is not it.

Unless otherwise specified and stated in the singular, the plural forms are included. That is, the components mentioned herein may mean the presence or addition of one or more other components.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. to be.

In other words, terms such as those defined in the commonly used dictionaries should be construed as meanings consistent with the meanings in the context of the related art, and, unless expressly defined herein, are construed in ideal or excessively formal meanings. It doesn't work.

Hereinafter, with reference to the accompanying drawings, a non-destructive inspection flaw detection apparatus according to an embodiment of the present invention will be described in detail.

3 is a block diagram schematically illustrating a flaw detector for non-destructive testing according to an embodiment of the present invention.

Referring to FIG. 3, the flaw detector for a non-destructive inspection according to an exemplary embodiment of the present invention may include a substrate 101, a sensor unit 103, a pressing member 105, and a fixing member 107.

The substrate 101 is a flexible substrate and may include, for example, a flexible printed circuit board.

When the substrate 101 contacts the beads, the substrate 101 may be bent to correspond to the shape of the beads.

The sensor unit 103 is arranged with a plurality of sensors, and may be attached to the substrate 101.

For example, the sensor unit 103 may be arranged with magnetic sensors for measuring the magnitude and direction of the magnetic field or magnetic field lines. The magnetic sensor is characterized by having sensitivity anisotropy on the sensor surface and maximum sensitivity to magnetic flux density incident vertically or horizontally.

Since the non-destructive inspection flaw detection apparatus according to an embodiment of the present invention uses densely arranged sensors, the defects can be inspected by estimating the shape and size of the small defects, which are difficult to measure by the prior art as shown in FIG. 2. It has the advantage of high spatial resolution.

One end of the pressing member 105 may be in contact with the sensor unit 103, and the other end thereof may be coupled to the fixing member 107. For example, in the non-destructive inspection apparatus according to an embodiment of the present invention, the pressing members 105 may be attached to the sensor unit 103, or the pressing members 105 may be placed on the sensor unit 103 to be in contact with each other. have.

The pressing members 105 may include an elastic body having an elastic force, and when the substrate 101 is bent to correspond to the shape of the bead, the pressing members 105 may be bent together according to the shape of the bent substrate 101.

When the pressing member 105 is bent according to the shape of the substrate 101, the pressing member 105 may apply a force such that the substrate 101 is in close contact with the surface of the object to be measured by the elastic force.

For example, the pressing member 105 is made of the same material as the shoe brush, the pressure member 105 in contact with the bent portion of the substrate 101 is also bent together, the substrate 101 by the elastic force of the shoe brush to bead and the base material Force may be applied to closely contact the surface of the measured object.

That is, the non-destructive inspection apparatus according to an embodiment of the present invention not only bends the substrate 101 according to the shape of the bead, but also the inclined portion (the portion where the beads meet the base material) of the substrate 101. By using the elastic force of the pressing member 105 to be in close contact with the surface of the object to be measured, there is an advantage of minimizing lift-off.

In addition, by minimizing lift-off, the contact plane of the bead and the sensor surface of the sensor unit 103 may be parallel to each other even in an inclined portion of the bead. In this case, since the magnetic flux density at the inclined portion of the bead is perpendicular to the sensor surface, there is an advantage that the maximum sensitivity can be obtained not only at the central portion of the bead but also at the magnetic flux density incident at the inclined portion.

The fixing member 107 is made of a material such as steel (Steel) is not bent, the pressing member 105 may be coupled to the lower surface.

Non-destructive testing flaw detection apparatus according to another embodiment of the present invention may further include a fixture (109).

The stationary body 109 may have one end coupled to a central portion of the bottom surface of the stationary member 107 in the width direction of the stationary member 107.

The pressing members 105 are coupled to the fixing member 107 symmetrically about the fixing body 109, and may be bent in the longitudinal direction of the fixing member 107 by the fixing body 109.

That is, the fixing member 109 may prevent the pressing members 105 from bending in the width direction of the fixing member 107, thereby increasing the force applied to the substrate 101 by the elastic force of the pressing members 105. have. As the applied force is increased, the substrate 101 may be in close contact with the surface of the object under test.

4 is a view briefly illustrating a flaw detector for non-destructive testing according to an embodiment of the present invention. Specifically, Figure 4a is a view showing an embodiment of a non-destructive inspection apparatus according to an embodiment of the present invention, Figure 4b is a view showing an example of the sensor unit 103, Figures 4c and 4d is a substrate 101 is a diagram illustrating an example in which the pressing members 105 are bent.

Referring to FIG. 4, the sensor unit 103 is a plurality of sensors densely arranged and may be attached on the substrate 101.

Since the sensor unit 103 is made of a flexible material that can be bent, it may be bent together with the substrate 101 to correspond to the shape of the bead.

Since one end of the pressing member 105 is in contact with the sensor unit 103 and the other end is coupled to the fixing member 107, the pressing member 105 may be bent in the x-axis and y-axis directions according to the bent shape of the substrate 101.

Since the pressing member 105 exerts a force in the z-axis direction on the substrate 101 by the elastic force, the substrate 101 may be in close contact with the surface of the object to be measured.

Non-destructive inspection flaw detection apparatus according to an embodiment of the present invention includes a plurality of pressing members 105, because the substrate 101 is forced by the elastic force of each of the pressing members 105, the lift off is uniform There is an advantage that is maintained.

On the contrary, with reference to FIG. 5, the result of analyzing the lift-off in the inclined part of the bead when the prior art pressing member consists of one is demonstrated.

5 is a view showing an embodiment of a conventional electromagnetic non-destructive inspection device. In detail, FIG. 5A is a view schematically illustrating a comparative embodiment, and FIG. 5B is a view illustrating an example in which the substrate and the second pressing member 201 are bent.

Referring to FIG. 5A, the second pressing member 201 is an elastic body having elastic force similarly to the pressing member 105. For example, the second pressing member 201 is a sponge having the same elastic force as the pressing member 105.

Referring to FIG. 5B, since the second pressing member 201 also has an elastic force, a force may be applied to the bent substrate. However, since the second pressing member 201 constitutes one member, the substrate cannot be applied to the surface of the inclined portion of the bead so that the lift-off is not uniform.

If the second pressing member 201 is manufactured using an elastic body having an excessively high elastic force, the substrate may be in close contact with the surface of the bead, but the friction force between the substrate and the object to be measured increases based on the elastic force. The problem of reduced lifespan occurs.

On the other hand, the pressing member 105 according to an embodiment of the present invention consists of a plurality of pressing members 105 separated from each other, by applying a force such that the substrate 101 is in close contact with the surface of the object to be measured, even with a small elastic force, The liftoff can be kept uniform.

6 is a view showing a non-destructive inspection flaw detection apparatus according to another embodiment of the present invention. Specifically, Figure 6a is a view showing an embodiment of a non-destructive inspection flaw detection apparatus according to another embodiment of the present invention, Figure 6b is a view showing an example in which the substrate 101 and the pressing member 105 is bent.

Referring to FIG. 6, the non-destructive testing flaw detection apparatus may further include a fixture 109.

The fixing body 109 may be coupled to a central portion of the lower surface of the fixing member 107 in one end thereof in the width direction (x-axis direction) of the fixing member 107.

The fixing member 109 prevents the pressing members 105 from bending in the width direction (x-axis direction) of the fixing member 107, so that the pressing members 105 are in the longitudinal direction (y-axis direction) of the fixing member 107. It can be induced to bend only with).

When the pressing members 105 are bent only in the y-axis direction by the fixing member 109, the elastic force of the pressing members 105 is further applied to the position of the substrate 101 corresponding to the inclined portion of the bead, thereby fixing the fixing body ( The substrate 101 may be in close contact with the inclined portion of the bead than when the 109 is not provided.

That is, since the pressing members 105 are not bent in the x-axis direction but bent in the y-axis direction, the elastic force of the pressing members 105 may be further applied to the position of the substrate 101 corresponding to the inclined portion of the bead. .

The embodiments of the present invention shown in Figures 4 and 6 by using the pressing member 105 having an elastic force to adhere the substrate 101 to the surface of the object to be measured, thereby maintaining the lift-off uniformly, bead and the sensor surface The magnetic flux density distribution can be measured more accurately by keeping the tangent plane of the parallel to ensure the maximum sensitivity of the magnetic flux density. In addition, there is an advantage that the defect can be measured more precisely and accurately through the plurality of sensors uniformly arranged in the sensor unit 103.

Although the description herein has been shown in several illustrative aspects, various modifications or changes may be made from the scope defined by the claims that follow, and the technical protection scope of the invention is set forth in the following claims. It must be decided by.

101: substrate
103: sensor unit
105: pressure member
107: fixing member
109: stationary
201: second pressing member

Claims (7)

Flexible substrates;
A sensor unit provided on the substrate and having a plurality of sensors arranged thereon;
A plurality of pressing members separated from each other, one end of which is in contact with the sensor and bent according to the shape of the substrate;
A fixing member having the other end of the pressing members coupled to a bottom surface thereof; And
One end includes a fixture coupled to the central portion of the lower surface of the fixing member in the width direction of the fixing member,
Nondestructive testing device. The method of claim 1,
The pressing member,
Including an elastic body having an elastic force (Elastic Force),
Nondestructive testing device. The method of claim 1,
The substrate,
Bent corresponding to the shape to the object to be measured,
Nondestructive testing device. The method of claim 3,
The pressing member,
When bent in accordance with the shape of the substrate, a force is applied so that the substrate is in close contact with the surface of the object to be measured,
Nondestructive testing device. delete The method of claim 1,
The pressing member,
Coupled to the fixing member symmetrically about the fixing body,
Nondestructive testing device. The method of claim 1,
The pressing member,
When bent in accordance with the shape of the substrate, bent in the longitudinal direction of the substrate by the fixture,
Nondestructive testing device.

Images