KR101867056B1 - Defect inspection device and method for tube - Google Patents

Abstract

The present invention relates to a defect inspection device and a method for a tube, which can inspect various metal defects that may be generated in an environment using high pressure gas and high temperature with non-destructive inspection. The defect inspection device for a tube comprises: a body formed in the shape of surrounding at least a portion of a tube; an ultrasonic sensor module installed in the body by sensing the tube with ultrasonic waves to detect a metal defect; and a moving distance measurement device installed at one side of the body, and coming in contact with a circumferential surface of the tube to measure a moving distance of the body on the tube.

Description

Technical Field [0001] The present invention relates to a tube defect inspection apparatus and a tube defect inspection method,

The present invention relates to a tube defect inspection apparatus and a tube defect inspection method, and more particularly, to a tube defect inspection apparatus and a tube defect inspection apparatus which can measure various metal defects that can be generated in a tube in a high- To a tube defect inspection method.

In general, a conventional tube defect inspection apparatus which is applied to the defect detection of a metal tube is applied to a large diameter diameter thick plate tube having a diameter of 2 cm and a thickness of 8 mm or more. Recently, the hydrogen fuel cell has become an automobile and hydrogen town electric energy source, and the necessity of defect inspection of the thin plate tube connected to the hydrogen gas main pipe by using the tube defect inspection apparatus is emerged.

Hydrogen energy is classified as a clean energy that does not cause carbon dioxide and environmental pollution. It is regarded as a future energy source. Hydrogen as atomic number 1 is known as a factor causing fatal defects in general materials including metals because of its small size. In order to dissipate hydrogen energy, it is necessary to use metal thin plate tubes. Therefore, it is necessary to provide a measuring instrument capable of detecting hydrogen defects and inspecting the defects.

However, such a conventional tube defect inspection apparatus has a problem that it can not be applied to defect inspection of a thin plate tube connected to a hydrogen gas main pipe. This includes the reason for the inadequate detection technology of hydrogen induced defects. Hydrogen induced defects classified as blisters, cracks, dents, etc. are still defects that are not measured by ultrasonic nondestructive testing It is dangerous. This is because the metal-defect generating mechanism and the form of the hydrogen-induced metal defect are very unique, and the conventional tube defect inspection apparatus has a problem that it is difficult to distinguish it from general metal defects.

The present invention has been made to solve the above problems and it is an object of the present invention to facilitate the detection of metal defects in hydrogen containers, pipes and parts related to hydrogen energy using a thin plate tube, The remaining life of the tube can be evaluated, and the inspection cycle can be set. It is also an object of the present invention to provide a tube defect inspection apparatus and a tube defect inspection method which can detect the danger of hydrogen explosion in advance by using hydrogen and ensure the stability of hydrogen use and the soundness of use of pipes, containers and parts. However, these problems are exemplary and do not limit the scope of the present invention.

According to one aspect of the present invention, a tube defect inspection apparatus is provided. The tube defect inspection apparatus includes: a body formed to surround at least a portion of a tube; An ultrasonic sensor module installed on the body for detecting metal defects by ultrasonic sensing the tube; And a movement distance measuring device installed at one side of the body and measuring a distance that the body moves on the tube in contact with the circumferential surface of the tube.

In the tube defect inspection apparatus, the ultrasonic sensor module may be disposed at an angle of 90 degrees with respect to the central axis of the body.

In the tube defect inspection apparatus, the ultrasonic sensor module may include: a longitudinal ultrasonic sensor for detecting a longitudinal metal defect of the tube; And a circumferential directional ultrasonic sensor that is spaced apart from the longitudinal ultrasonic sensor by a predetermined distance in a forward or backward direction of the body and detects a circumferential metal defect of the tube.

The apparatus for inspecting a tube defect may further include a mounting portion provided on the body and adapted to adjust a contact position between the ultrasonic sensor module and a circumferential surface of the tube.

In the tube defect inspection apparatus, the mounting portion may include: a movable table on which the ultrasonic sensor module is installed; A first position adjuster installed to penetrate the body and elastically supporting one side of the movable table so that the movable table can be vertically moved or tilted; A second position adjuster installed to penetrate the body and elastically supporting the other side of the movable table so that the movable table can be vertically moved or tilted; And an elastic member inserted in the first position adjuster and the second position adjuster to generate a restoring force to press the movable table in the tube direction.

In the tube defect inspection apparatus, the movement distance measuring device may include: a wheel rotating in contact with a circumferential surface of the tube; And an encoder for sensing the rotational speed of the wheel and measuring the moving position of the body on the tube.

In the tube defect inspection apparatus, the body may include: a first portion formed to surround one side of the tube; And a second portion formed in a shape surrounding the other side of the tube and fixed to the first portion by a fixture.

In the tube defect inspection apparatus, the body may include a handle provided on one side of the body so that the body can be easily moved back and forth in the longitudinal direction of the tube.

The tube defect inspection apparatus may further include a sealing member installed between the circumferential surface of the tube and the inner surface of the body so that the body surrounding the tube is not shaken.

The ultrasonic sensor module may further include a controller for receiving a sensing signal obtained by ultrasonic sensing the ultrasonic sensor module to determine whether the tube is metal defective.

In the tube defect inspection apparatus, the control unit may include: a standard signal storage unit for storing the standard signal by measuring a standard sample for setting a standard signal for each representative metal defect in the tube with the ultrasonic sensor module; And a metal defect discrimination unit for discriminating the type of metal defect in the tube by comparing the standard signal with a sensing signal obtained by ultrasonic sensing the tube by the ultrasonic sensor module.

According to one aspect of the present invention, a method for inspecting a tube defect is provided. A standard signal storage step of storing the standard signal by measuring a standard sample for setting a standard signal for each representative metal defect of the tube with an ultrasonic sensor module; An ultrasonic sensing step of ultrasonic sensing the tube by the ultrasonic sensor module installed on the body while moving the body forward or backward in the longitudinal direction of the tube to generate a sensing signal; And a metal defect discrimination step of discriminating a metal defect type of the tube by comparing the sensing signal and the standard signal.

According to an embodiment of the present invention as described above, it is possible to facilitate detection of metal defects in a hydrogen container, piping, and parts related to hydrogen energy using a thin plate tube, Life evaluation is possible, and the inspection cycle can be set.

In addition, it is possible to implement a tube defect inspection apparatus and a tube defect inspection method which can ensure the stability of hydrogen use and ensure soundness of piping, containers, and parts by sensing the danger of hydrogen explosion in advance when using hydrogen. Of course, the scope of the present invention is not limited by these effects.

1 is a cross-sectional view showing a tube defect inspection apparatus according to an embodiment of the present invention.
2 is a sectional view showing an ultrasonic sensor module of the tube defect inspection apparatus of FIG.
3 is a cross-sectional view showing a moving distance measuring apparatus of the tube defect inspection apparatus of FIG.
4 is a flowchart illustrating a method of inspecting a tube defect according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The embodiments of the present invention are described in order to more fully explain the present invention to those skilled in the art, and the following embodiments may be modified into various other forms, It is not limited to the embodiment. Rather, these embodiments are provided so that this disclosure will be more thorough and complete, and will fully convey the concept of the invention to those skilled in the art. In the drawings, the thickness and size of each layer are exaggerated for convenience and clarity of explanation.

It is to be understood that throughout the specification, when an element such as a film, region or substrate is referred to as being "on", "connected to", "laminated" or "coupled to" another element, It will be appreciated that elements may be directly "on", "connected", "laminated" or "coupled" to another element, or there may be other elements intervening therebetween. On the other hand, when one element is referred to as being "directly on", "directly connected", or "directly coupled" to another element, it is interpreted that there are no other components intervening therebetween do. Like numbers refer to like elements. As used herein, the term "and / or" includes any and all combinations of one or more of the listed items.

Although the terms first, second, etc. are used herein to describe various elements, components, regions, layers and / or portions, these members, components, regions, layers and / It is obvious that no. These terms are only used to distinguish one member, component, region, layer or section from another region, layer or section. Thus, a first member, component, region, layer or section described below may refer to a second member, component, region, layer or section without departing from the teachings of the present invention.

Also, relative terms such as "top" or "above" and "under" or "below" can be used herein to describe the relationship of certain elements to other elements as illustrated in the Figures. Relative terms are intended to include different orientations of the device in addition to those depicted in the Figures. For example, in the figures, when the element is turned over, the elements depicted as being on the upper surface of the other elements are oriented on the lower surface of the other elements. Thus, the example "top" may include both "under" and "top" directions depending on the particular orientation of the figure. If the elements are oriented in different directions (rotated 90 degrees with respect to the other direction), the relative descriptions used herein can be interpreted accordingly.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a," "an," and "the" include singular forms unless the context clearly dictates otherwise. Also, " comprise "and / or" comprising "when used herein should be interpreted as specifying the presence of stated shapes, numbers, steps, operations, elements, elements, and / And does not preclude the presence or addition of one or more other features, integers, operations, elements, elements, and / or groups.

Hereinafter, embodiments of the present invention will be described with reference to the drawings schematically showing ideal embodiments of the present invention. In the figures, for example, variations in the shape shown may be expected, depending on manufacturing techniques and / or tolerances. Accordingly, the embodiments of the present invention should not be construed as limited to the particular shapes of the regions shown herein, but should include, for example, changes in shape resulting from manufacturing.

1 is a sectional view showing a tube defect inspection apparatus 100 according to an embodiment of the present invention. 2 is a sectional view showing the ultrasonic sensor module 20 of the tube defect inspection apparatus 100 of FIG. 1 and FIG. 3 is a sectional view of the ultrasonic sensor module 20 of the tube defect inspection apparatus 100 of FIG. Sectional view.

1 to 3, a tube defect inspection apparatus 100 according to an embodiment of the present invention includes a body 10, an ultrasonic sensor module 20, a movement distance measuring device 30 ), A mounting portion 40, and a sealing member 50.

As shown in FIG. 1, the body 10 may be formed in a shape that surrounds at least a part of the tube T. For example, the body 10 may be a structure having adequate strength and durability capable of receiving and supporting the ultrasonic sensor module 20, the moving distance measuring device 30, the mount portion 40, and the sealing member 50 have. For example, the body 10 may be a structure selected from a material selected from the group consisting of steel, stainless steel, aluminum, magnesium, and zinc. However, the body 10 is not necessarily limited to Fig. 1, but may be provided with an ultrasonic sensor module 20, a movement distance measuring device 30, a mount portion 40 and a sealing member 50, Members of various materials can be applied.

More specifically, the body 10 has a first portion 11 formed to surround one side of the tube T and a second portion 11 formed to surround the other side of the tube T, 1 portion 11 and a second portion 12 which is fixed.

For example, the body 10 may include a first portion 11 and a second portion 12 (not shown) so as to allow the tube T to pass through the body 10, And can be coupled to each other around the tube T. [ At this time, the first portion 11 and the second portion 12 can be engaged and fixed using a fixture B such as a bolt member. Also, the combination of the first portion 11 and the second portion 12 is not limited to the engagement using the fastener B, and a very wide variety of engagement methods such as hook engagement can be applied.

The first part 11 and the second part 12 are joined to each other so that the tube 10 can pass through and pass through the body 10 so that the body 10 can move forward or backward in the longitudinal direction of the tube T. [ can do. At this time, a handle (H) may be provided on one side of the body (10) so that the body (10) can be easily moved forward or backward in the longitudinal direction of the tube (T). Between the circumferential surface of the tube T and the inner circumferential surface of the body 10 so that the body 10 surrounding the tube T does not shake when the body 10 moves forward or backward in the longitudinal direction of the tube T, A sealing member 50 may be provided.

2, the ultrasonic sensor module 20 may be installed on the body 10 so that the tube T can be ultrasonically sensed to detect metal defects. More specifically, the ultrasonic sensor module 20 can be equally spaced at an angle of 90 degrees with respect to the central axis of the body 10. For example, the ultrasonic sensor module 20 may be installed so that at least a portion of the ultrasonic sensor module 20 protrudes toward the inner diameter side of the body 10 so that the ultrasonic sensor module 20 can contact the circumferential surface of the tube T at predetermined predetermined intervals. Accordingly, the ultrasonic sensor module 20 provided on the body 10 is arranged at an angle of 90 degrees with respect to the tube T, and the ultrasonic sensor module 20, along with the body 10, is advanced or retracted in the longitudinal direction of the tube T And the entire circumferential surface of the tube T is ultrasonically sensed to detect metal defects.

The ultrasonic sensor module 20 includes a longitudinal ultrasonic sensor 21 and a longitudinal ultrasonic sensor 21 for detecting a metal defect in the longitudinal direction of the tube T and a predetermined And a circumferential ultrasonic sensor 22 installed at a distance from the circumference of the tube T and detecting a circumferential metal defect of the tube T. [

For example, four longitudinal ultrasonic sensors 21 are disposed in the body 10 so as to surround the tube T at an angle of 90 degrees, and the circumferential ultrasonic sensor 22 is connected to the longitudinal ultrasonic sensor 21 Four pieces may be arranged at an angle of 90 degrees to surround the tube T at a position spaced apart from the body 10 by a predetermined distance in the forward or backward direction of the body 10,

Therefore, the longitudinal ultrasonic sensor 21 and the circumferential ultrasonic sensor 22 are installed in the body 10 in eight channels in total, and move forward or backward in the longitudinal direction of the tube T together with the body 10, It is possible to precisely ultrasonically sense the entire circumferential surface of the substrate T to detect metal defects.

2, the mounting portion 40 may be provided on the body 10 to adjust the contact position of the ultrasonic sensor module 20 with the circumferential surface of the tube T. [ More specifically, the mount portion 40 includes a movable base 41 on which the ultrasonic sensor module 20 is installed, and a movable base 41 on which the movable base 41 can be vertically moved or tilted A first position adjuster 42 for elastically supporting one side of the movable base 41 so that the movable base 41 can be vertically moved or tilted so that the movable base 41 can be vertically moved or tilted, The second position adjusting member 43 and the first position adjusting member 42 and the second position adjusting member 43 elastically supporting the other side of the movable table 41 in the direction of the tube T And an elastic member 44 for generating a restoring force so that the elastic member 44 can be rotated.

For example, the movable table 41 can be coupled with the ultrasonic sensor module 20 to support the ultrasonic sensor module 20 in the space between the inner diameter surface of the body 10 and the circumferential surface of the tube T. [ One side of the movable base 41 is elastically supported such that the first position adjuster 42 is capable of forward and backward flow and the other side of the movable base 41 is moved forward and backward by the second position adjuster 43. [ The first position adjusting member 42 and the second position adjusting member 43 are vertically moved in accordance with the diameter and the shape of the tube T so that the movable table 41 is rotated in the vertical direction It can be moved up or down or tilted according to the shape.

A female screw portion may be formed on the outer surface of the first position adjuster 42 and the second position adjuster 43 and a female screw may be formed on the body 10 that accommodates the position adjusters 42 and 43 . Accordingly, the user can manually adjust the up and down movement and tilt of the movable base 41 on which the ultrasonic sensor module 20 is installed by rotating the first position adjuster 42 and the second position adjuster 43, The contact interval and the contact angle between the tube T and the ultrasonic sensor module 20 can be arbitrarily set by the user.

At this time, the elastic member 44 is coaxially inserted into the first position adjuster 42 and the second position adjuster 43 so that a restoring force is applied between the body 10 and the movable table 41 in the direction of the tube T So that the longitudinal ultrasonic sensor 21 or the circumferential ultrasonic sensor 22 can generate a force to contact the circumferential surface of the tube T. [

Therefore, the mounting portion 40 adjusts the position of the ultrasonic sensor module 20, so that the contact distance and the contact angle with the circumferential surface of the tube T can be easily adjusted. The ultrasonic sensor module 20 can detect a metal defect optimized for a thin plate tube having a diameter of 2 cm or less and a thickness of 8 mm or less by adjusting the contact distance and contact angle between the ultrasonic sensor module 20 and the circumferential surface of the tube T. [ (20). ≪ / RTI >

3, the moving distance measuring device 30 is installed on one side of the body 10 and contacts the circumferential surface of the tube T so that the body 10 moves on the tube T A distance can be measured.

More specifically, the moving distance measuring apparatus 30 detects the number of revolutions of the wheel 31 and the wheel 31 rotating in contact with the circumferential surface of the tube T, And an encoder 32 for measuring the movement position. At this time, the wheel 31 and the encoder 32 are in direct contact with each other to transmit the rotational motion of the wheel 31 to the encoder 32, or to the rotational motion of the wheel 31 by a power transmitting member such as a belt, 32).

The wheel 31 rotates in contact with the circumferential surface of the tube T in addition to the function of transmitting the rotational motion to the encoder 32 so that the body 10 surrounding the tube T is rotated by the tube T, So as to smoothly move forward or backward in the longitudinal direction of the vehicle.

The moving distance measuring device 30 detects the number of rotations of the wheel 31 rotating in contact with the circumferential surface of the tube T by the encoder 32 and detects the number of rotations of the wheel 31 The position of the metal defect generated on the tube T can be easily grasped by calculating the moving distance of the body 10 moving forward or backward in the longitudinal direction of the tube T by using the diameter of the tube T. [

Although not shown, a tube defect inspection apparatus 100 according to an embodiment of the present invention includes a controller (not shown), and receives a sensing signal obtained by ultrasonic sensing the tube T by the ultrasonic sensor module 20 It is possible to determine whether or not the tube T has a metal defect.

More specifically, the control unit includes a standard signal storage unit for storing a standard signal for measuring a standard sample for setting a standard signal for each representative metal defect of the tube T with the ultrasonic sensor module 20, and an ultrasonic sensor module And a metal defect discrimination unit for discriminating a metal defect type of the tube T by comparing the sensing signal obtained by ultrasonic sensing the tube T with a standard signal.

For example, the standard sample is a standard defect of the inner surface or the outer surface of the tube T measured by the ultrasonic sensor module 20, and the standard of the sensor signal for each representative defect is set by ultrasonic sensing with the ultrasonic sensor module 20 . Thus, the defect type of the tube T can be precisely classified through comparison of the sensor signals set as the standard. At this time, the standard sample is a sample having at least one of a surface layer defect, a blister, a hydrogen induced void, a hydrogen induced crack, a crack and a dent Lt; / RTI >

The apparatus for inspecting a tube defect 100 according to an embodiment of the present invention includes a tubular defect inspection apparatus 100 including a body 10 in which a longitudinal direction ultrasonic sensor 21 and a circumferential direction ultrasonic sensor 22 are movable forward or backward in the longitudinal direction of the tube T 10 so as to move forward or backward along the length of the tube T together with the body 10 to precisely sense the entire circumferential surface of the tube T to ultrasonically detect the metal defect .

The mounting portion 40 adjusts the positions of the longitudinal ultrasonic sensor 21 and the circumferential ultrasonic sensor 22 so as to adjust the contact distance and the contact angle with the circumferential surface of the tube T, And the arrangement of the ultrasonic sensor module 20 capable of detecting metal defects optimized for the thin plate tube having a thickness of 8 mm or less can be realized.

The encoder 32 of the moving distance measuring device 30 senses the number of revolutions of the wheel 31 rotating in contact with the circumferential surface of the tube T and detects the number of revolutions of the wheel 31 and the number of revolutions of the wheel 31 The position of the metal defect generated on the tube T can be easily grasped by calculating the moving distance of the body 10 moving forward or backward in the longitudinal direction of the tube T by using the diameter of the tube T. [

Therefore, the tube defect inspection apparatus 100 according to an embodiment of the present invention can facilitate detection of metal defects in hydrogen containers, pipes, and components related to hydrogen energy using a thin plate tube, It is possible to evaluate the remaining life of the tube T with respect to the tube T, and the inspection cycle can be set. In addition, when hydrogen is used, it is possible to detect the danger of hydrogen explosion in advance to ensure the stability of hydrogen use and to secure the usability of pipes, containers and parts.

4 is a flowchart illustrating a method of inspecting a tube defect according to an embodiment of the present invention.

4, a method of inspecting a tube defect according to an exemplary embodiment of the present invention includes measuring a standard sample for setting a standard signal for each representative metal defect in the tube T with the ultrasonic sensor module 20 A standard signal storing step S10 for storing the standard signal and an ultrasonic sensor module 20 installed on the body 10 for moving the tube 10 forward or backward in the longitudinal direction of the tube T, (S20) for sensing the ultrasonic wave to generate a sensing signal, and a metal defect discriminating step (S30) for discriminating a metallic defect type of the tube (T) by comparing the sensing signal and the standard signal .

More specifically, in the standard signal storage step S10, a standard sample for setting a standard signal for each representative metal defect of the tube T in the standard signal storage unit of the control unit is measured by the ultrasonic sensor module 20, . ≪ / RTI >

In the ultrasonic sensing step S20, the ultrasonic sensor module 20 installed on the body 10 is equally arranged at an angle of 90 degrees to surround the tube T, and the tube T, together with the body 10, The entire circumferential surface of the tube T is ultrasonically sensed to generate a sensing signal.

In the metal defect determination step S30, the metal defect determination unit of the control unit compares the sensing signal obtained by ultrasonic sensor sensing the tube T with the standard signal stored in the standard signal storage unit, It is possible to determine the type of metal defect in the metal layer T.

Therefore, the method for inspecting a tube defect according to an embodiment of the present invention can facilitate detection of metal defects in a hydrogen container, piping, and parts related to hydrogen energy using a thin plate tube, (T) can be evaluated and the inspection period can be set. In addition, when hydrogen is used, it is possible to detect the danger of hydrogen explosion in advance to ensure the stability of hydrogen use and to secure the usability of pipes, containers and parts.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

10: Body
20: Ultrasonic sensor module
30: Moving distance measuring device
40: Mount portion
50: Sealing member
T: Tube
H: Handle portion
100: Tube defect inspection system

Claims (12)

A body formed in a shape surrounding at least a portion of the tube;
An ultrasonic sensor module installed on the body for detecting metal defects by ultrasonic sensing the tube;
A moving distance measuring device installed at one side of the body and measuring a distance that the body moves on the tube in contact with the circumferential surface of the tube; And
And a mounting part installed on the body and adjusting a contact position of the ultrasonic sensor module with a circumferential surface of the tube,
The ultrasonic sensor module includes:
A longitudinal direction ultrasonic sensor installed on the body so as to surround the tube with respect to a center axis of the body so as to be equally spaced at an angle of 90 degrees and to detect metal defects in the longitudinal direction of the tube; And
Four longitudinally arranged ultrasonic sensors are disposed on the body at a position spaced apart from the longitudinal direction ultrasonic sensor by a predetermined distance in the forward or backward direction of the body so as to surround the tube with respect to the central axis of the body, And a circumferential ultrasonic sensor for detecting circumferential metal defects of the tube,
The mounting portion includes:
A movable table on which the ultrasonic sensor module is installed;
A first position adjuster installed to penetrate the body and elastically supporting one side of the movable table so that the movable table can be vertically moved or tilted;
A second position adjuster installed to penetrate the body and elastically supporting the other side of the movable table so that the movable table can be vertically moved or tilted; And
An elastic member inserted in the first position adjuster and the second position adjuster to generate a restoring force so as to press the movable table in the tube direction;
And the tube defect inspection device. delete delete delete delete The method according to claim 1,
Wherein the moving distance measuring device comprises:
A wheel rotating in contact with the circumferential surface of the tube; And
An encoder that senses the number of revolutions of the wheel and measures a moving position of the body on the tube;
And the tube defect inspection device. The method according to claim 1,
The body,
A first portion formed in a shape surrounding one side of the tube; And
A second portion formed to surround the other side of the tube and fixed to the first portion by a fastener;
And the tube defect inspection device. The method according to claim 1,
The body,
A handle provided on one side of the body so that the body can be easily moved back and forth in the longitudinal direction of the tube;
And the tube defect inspection device. The method according to claim 1,
A sealing member installed between the circumferential surface of the tube and the inner diameter surface of the body so that the body surrounding the tube is not shaken;
The tube defect inspection apparatus further comprising: The method according to claim 1,
A controller receiving ultrasonic sensing signals from the ultrasonic sensor module to determine whether the tube is metal defective;
The tube defect inspection apparatus further comprising: 11. The method of claim 10,
Wherein,
A standard signal storage unit for storing the standard signal by measuring a standard sample for setting a standard signal for each representative metal defect in the tube with the ultrasonic sensor module; And
A metal defect discrimination unit for discriminating a metal defect type of the tube by comparing the sensing signal obtained by ultrasonic sensing the tube with the standard signal;
And the tube defect inspection device. delete

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