JP7267108B2 - Weld inspection device - Google Patents

Description

The present invention relates to a weld inspection device. More specifically, the present invention relates to an inspection device for welded parts such as bottom plates of oil tanks.

The bottom of a large liquid storage tank, such as an oil tank, is formed by stacking a large number of plates on the ground and welding them from the side facing away from the ground. Patent Document 1 discloses an inspection apparatus and an inspection method for inspecting a welded part with a simple operation for an inspection object such as a bottom plate of an oil tank, in which plate materials are overlapped on the ground surface and fillet welded. is disclosed. The inspection device described in Patent Document 1 includes a vibrating body that applies an impact to the first plate material among the first and second plate materials that are fillet-welded, and a welded portion between the first plate material and the second plate material. and a sensor for measuring the vibration intensity of the shock wave propagated from the first plate to the second plate through the. Furthermore, the inspection device includes a computing unit that computes an inspection parameter (eg, throat thickness) of the weld using the vibration intensity measured by the sensor.

The inspection apparatus described in Patent Literature 1 includes a table and a shaft member that is inserted into a guide penetrating the table and movable in a direction orthogonal to the table surface. The shaft member is connected to the sensor through a universal joint, and a spring member is provided between the universal joint and the guide. The sensor is pressed against the second plate through the universal joint by the elastic force of the spring member.

JP 2015-184076 A

In the inspection device described in Patent Document 1, the sensor is connected via a universal joint to a spring member for pressing the sensor against the second plate. For this reason, the waveform indicating the vibration intensity measured by the sensor may be distorted.

Also, the diameter of the bottom plate of a cylindrical petroleum tank reaches, for example, 100 m. Such a bottom plate is formed by stacking a huge number of plate materials on the ground surface without gaps and fillet welding them from the side not facing the ground surface. For this reason, the total length of the welded portion between plate materials is enormous, and the number of inspection points is also enormous. The inspection apparatus of Patent Document 1 is not suitable for efficiently inspecting a huge number of inspection points.

SUMMARY OF THE INVENTION In view of the above-described problems, the present invention provides a weld inspecting apparatus that can efficiently inspect a huge number of inspected points with less disturbance in the waveform indicating the vibration intensity measured by the sensor. for the purpose.

A first aspect of the present invention is a welded portion inspection device for inspecting a welded portion in which a material to be welded on the far side and a material to be welded on the front side are welded in a stepped manner as viewed from the detection side,
an impact target member determination unit that determines one of the back side welding material and the front side welding material;
a vibrating body that applies an impact to the one welded material determined by the hit target member determination unit;
a first sensor for measuring a first vibration intensity of a shock wave propagated by the impact from one of the materials to be welded to the other material to be welded through the welded portion;
a second sensor for measuring a second vibration intensity of the shock wave propagated through the one workpiece due to the impact;
a storage device storing correlation data between the sample vibration intensity ratio and the throat thickness of the weld, which is obtained in advance using a plurality of test pieces having different throat thicknesses of the weld;
Substituting the ratio of the first vibration intensity measured by the first sensor and the second vibration intensity measured by the second sensor into the correlation data stored in the storage device and a computing unit that computes the throat thickness of the welded portion .

In the welded portion inspection device of the first aspect, the hit target member determination unit may detect a step of the welded portion and determine the running direction of the welded portion inspection device.

A weld inspection device of a first aspect comprises a first holder that supports the first sensor with an upper surface of the first sensor open ;
A second holder that supports the second sensor with an upper surface of the second sensor open may further be provided .

In the weld inspection device of the first aspect, the material to be welded on the back side and the material to be welded on the front side may be fillet welded.

The weld inspection apparatus of the first aspect may further include a vertical movement mechanism that vertically moves the first holder and the second holder.

A weld zone inspection apparatus according to a first aspect includes a traveling device capable of traveling the material to be welded on the back side and the material to be welded on the front side,
a lateral direction moving mechanism provided in the traveling device for moving the first holder and the second holder in a width direction perpendicular to the traveling direction of the traveling device;
a control device provided in the traveling device for controlling the lateral movement mechanism and the traveling device;
The control device may include the calculation unit.

A weld inspection device of a first aspect comprises a storage unit storing target position information,
a position sensor that detects the position of the traveling device,
The control device may move the traveling device to the target position based on the position of the traveling device detected by the position sensor and target position information stored in the storage unit.

In the weld inspection device of the first aspect, the traveling device
a wheel capable of traveling on the material to be welded on the back side and the material to be welded on the front side;
a housing supported by the wheels;
a battery that drives the wheels;
an independent suspension capable of independently adjusting the height of the wheels with respect to the housing,
The control device may control the independent suspension to maintain horizontality of the housing with respect to the material to be welded on the back side and the material to be welded on the front side.

The weld inspection device of the first aspect further includes a step detection sensor that detects a step between the material to be welded on the back side and the material to be welded on the front side to specify the position of the weld,
The control device controls the lateral movement mechanism so that the position of the weld identified by the step detection sensor is between the vibrating body and the first sensor that measures the first vibration intensity. The first holder may be moved in the width direction so as to be positioned at .

In the weld inspection device of the first aspect, the material to be welded on the far side and the material to be welded on the front side may constitute a part of a bottom plate of an oil tank.

In the weld inspection device of the first aspect, the traveling device may further include a headlight and an obstacle detection device.

According to the first and second aspects of the present invention, there is little disturbance in the waveform indicating the vibration intensity measured by the sensor, and a vast number of inspection points can be efficiently inspected. An apparatus is provided.

1 is a conceptual diagram showing an example of an inspection unit and a control unit of a weld inspection device according to Embodiment 1 of the present invention; FIG. 4 is a conceptual diagram showing an example of the positional relationship between the first vibrating body and the sensor section of the weld inspection device according to the first embodiment; FIG. 4 is a conceptual diagram showing an example of the positional relationship between the second vibrating body and the sensor section of the weld inspection device according to the first embodiment; FIG. 2 is a conceptual diagram showing an example of an internal configuration of a control circuit according to Embodiment 1; FIG. 4 is a flow chart showing a method for inspecting the throat thickness of a weld by the weld inspecting apparatus according to Embodiment 1. FIG. 1 is a conceptual diagram showing an example of a weld inspection device according to Embodiment 1. FIG. FIG. 2 is a conceptual diagram showing an example of an internal configuration of a control device mounted on the weld zone inspection apparatus according to Embodiment 1; 4 is a plan view showing an example of the bottom plate of the oil tank in Embodiment 1. FIG. FIG. 4 is a conceptual diagram showing an example of inspecting the throat thickness of a welded portion by applying an impact to the material to be welded on the far side with the first vibrating body according to Embodiment 1; FIG. 4 is a conceptual diagram showing an example of inspecting the throat thickness of a welded portion by applying an impact to the material to be welded on the far side with the second vibrating body according to Embodiment 1; 4 is a flow chart showing a method for inspecting the throat thickness of the welded portion of the oil tank with the welded portion inspection device according to the first embodiment. FIG. 7 is a conceptual diagram showing an example of a vibrating body and a sensor section of a weld inspection device according to Embodiment 2 of the present invention; (a) is a conceptual diagram showing an example of rotating the stage of the weld inspection device according to the second embodiment. (b) is a conceptual diagram showing an example of inspecting the throat thickness of the welded portion by applying an impact to the material to be welded on the far side with the first vibrating body according to the second embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. It should be noted that the embodiment described below is merely an example of the present invention, and it goes without saying that the embodiment of the present invention can be modified as appropriate without changing the gist of the present invention.

<Embodiment 1>
(Inspection unit)
A specific example of the weld zone inspection apparatus of the present invention will be described. As shown in FIG. 1 , the weld inspection apparatus 10 includes an inspection unit 20 that inspects the weld 15 of the weld plate material 12 and an inspection control unit 80 that controls the inspection unit 20 .
The plate material 12 to be welded is a plate material in which an end portion 13a of a first material to be welded 13 and an end portion 14a of a second material to be welded 14 are superimposed in a stepped manner and welded at a welding portion 15. .
The first material to be welded 13 is the "rear side to be welded" when viewed from the side where the welded portion 15 of the welded plate material 12 is detected. The second weld material 14 is the "front weld material" when viewed from the detection side. Hereinafter, the first material to be welded 13 may be referred to as "the material to be welded 13 on the back side", and the second material to be welded 14 may be described as the "material to be welded 14 on the front side".

The inspection section 20 includes a vibrating body 21 for applying an impact to the first weld material 13, a sensor section 24 for measuring the vibration intensity of the shock wave, a stage device 28 for supporting the sensor section 24, and a stage device 28. It mainly includes an electric slider (vertical movement mechanism) 30 that moves in the vertical direction.

The stage device 28 includes two first legs 32 , two second legs 33 , and a stage 34 attached above the first legs 32 and the second legs 33 . The stage device 28 is placed on the welding plate material 12 welded by the welding part 15 .

The stage 34 is a table that is rectangular in plan view. The two first legs 32 are fixed to one corner 34a of the four corners of the stage 34 via a first slider 32a so as to be able to expand and contract. A first magnet member 32 b is provided at the tip of the first leg portion 32 . The tip of the first leg portion 32 is fixed to the first material to be welded 13 by the magnetic force of the first magnet member 32b.
The two second legs 33 are fixed to the other corner 34b of the four corners of the stage 34 via a second slider 33a so as to be able to expand and contract. A second magnet member 33 b is provided at the tip of the second leg portion 33 . The tip of the second leg portion 33 is fixed to the second material to be welded 14 by the magnetic force of the second magnet member 33b.
The first leg portion 32 is configured to be extendable by the first slider 32a. The second leg portion 33 is configured to be extendable by the second slider 33a. The first leg 32 and the second leg 33 are configured to be movable in a direction perpendicular to the surface (table surface) of the stage 34 . The stage 34 is supported by the first leg 32 and the second leg 33 and adjusted to be parallel to the welding plate 12 . It should be noted that the stage device 28 may be made independent only by the electric slider 30 without providing the first leg portion 32 and the second leg portion 33 to the stage device 28 .

In a region of the stage 34 on the side where the first leg 32 is provided, a first opening 34c penetrates in a direction perpendicular to the surface of the stage 34 . A first guide 35 is attached to pass through the first opening 34c. A first shaft member 36 is supported by the first guide 35 so as to be movable in the vertical direction orthogonal to the surface of the stage 34 . A linear guide, for example, is used as the first guide 35 .

A second opening 34 d penetrates in a direction perpendicular to the surface of the stage 34 in a region of the stage 34 where the second leg 33 is provided. A second guide 38 is attached to pass through the second opening 34d. A second shaft member 39 is supported by the second guide 38 so as to be movable in the vertical direction orthogonal to the surface of the stage 34 . A linear guide, for example, is used as the second guide 38 .

In a region of the stage 34 on the side of the first guide 35 , a third opening 34 e penetrates in a direction perpendicular to the surface of the stage 34 . A third guide 42 is attached to pass through the third opening 34e. A third shaft member 43 is supported by the third guide 42 so as to be movable in the vertical direction orthogonal to the surface of the stage 34 . A linear guide, for example, is used as the third guide 42 .

In addition, in the area of the stage 34 on the side of the second guide 38 , a fourth opening 34 f penetrates in a direction orthogonal to the surface of the stage 34 . A fourth guide 44 is attached to pass through the fourth opening 34f. A fourth shaft member 46 is supported by the fourth guide 44 so as to be movable in the vertical direction perpendicular to the surface of the stage 34 . A linear guide, for example, is used as the fourth guide 44 .

Thereby, the first shaft member 36 , the second shaft member 39 , the third shaft member 43 , and the fourth shaft member 46 can be smoothly slid vertically with respect to the stage 34 . Alternatively, slide bearings or the like may be used as the first guide 35 , the second guide 38 , the third guide 42 and the fourth shaft member 46 . Alternatively, a configuration in which the first guide 35, the second guide 38, the third guide 42, and the fourth shaft member 46 are not provided is also possible. That is, the first shaft member 36, the second shaft member 39, the third shaft member 43, and the fourth shaft member 46 are arranged in the first opening 34c, the second opening 34d, and the third opening 34d formed in the stage 34. The opening 34e and the inner surface of the fourth opening 34f may be slidably moved.

A vibrating body 21 is attached to the first shaft member 36 and the fourth shaft member 46 . The vibrating body 21 includes a first vibrating body 22 connected to the first shaft member 36 and a second vibrating body 23 connected to the fourth shaft member 46 .
A first vibrating body 22 is connected to the first shaft member 36 . The first shaft member 36 has an upper first upper shaft 36a and a lower first lower shaft 36b extending on the same straight line. The first upper shaft 36 a is inserted through the first guide 35 . A first flange 36c is formed at the upper end of the first upper shaft 36a. The first flange 36 c prevents the first shaft member 36 from slipping out of the first guide 35 due to impact from the first vibrating body 22 or the like.

The first upper shaft 36 a and the first lower shaft 36 b are connected by a first movable member 45 . The first movable member 45 finely adjusts the angle of the first lower shaft 36b with respect to the first upper shaft 36a. For example, a universal joint can be used as the first movable member 45 . A first vibrating body 22 is connected to the lower end of the first lower shaft 36b. For example, a solenoid can be used as the first vibrating body 22 .
A first vibrating body magnet member 48 is arranged at the tip of the vibrating housing 47 of the first vibrating body 22 . The first vibrating body magnet member 48 is attracted to the welding plate material 12 (the material to be welded 13 ), and brings the vibrating housing 47 of the first vibrating body 22 into close contact with the welding plate material 12 . Note that the vibrating housing 47 may be brought into direct contact with the welding plate material 12 without providing the vibrating magnet member 48 at the tip of the vibrating housing 47 .

The first vibrating body 22 is connected to the first shaft member 36 on the surface side of the stage 34 by the first movable member 45 so that the joining angle can be freely changed. In the first shaft member 36, when the first leg portion 32 and the second leg portion 33 are fixed to the welding plate material 12, the first vibrating body 22 vibrates the welding plate material 12 (particularly, the material to be welded 13 on the far side). It has a length that touches the The first vibrating body 22 is a vibrating body that applies an impact to the material to be welded 13 on the far side (that is, the first material to be welded 13).

A second vibrating body 23 is connected to the fourth shaft member 46 . The fourth shaft member 46 has an upper fourth upper shaft 46a and a lower fourth lower shaft 46b extending on the same straight line. The fourth upper shaft 46 a is inserted through the fourth guide 44 . A fourth flange 46c is formed at the upper end of the fourth upper shaft 46a. The fourth flange 46 c prevents the fourth shaft member 46 from slipping out of the fourth guide 44 due to impact from the second vibrating body 23 or the like.

The fourth upper shaft 46 a and the fourth lower shaft 46 b are connected by a fourth movable member 49 . The fourth movable member 49 finely adjusts the angle of the fourth lower shaft 46b with respect to the fourth upper shaft 46a. For example, a universal joint can be used as the fourth movable member 49 . A second vibrating body 23 is connected to the lower end of the fourth lower shaft 46b. For example, a solenoid can be used as the second vibrating body 23 .
A second vibrating body magnet member 56 is arranged at the tip of the vibrating housing 53 of the second vibrating body 23 . The second vibrating body magnet member 56 is attracted to the welding plate material 12 (the material to be welded 14 ), and brings the vibrating housing 53 of the second vibrating body 23 into close contact with the welding plate material 12 . Note that the vibrating housing 53 may be brought into direct contact with the welding plate material 12 without providing the vibrating magnet member 56 at the tip of the vibrating housing 53 .

The second vibrating body 23 is joined to a fourth shaft member 46 on the surface side of the stage 34 by a fourth movable member 49 so that the joint angle can be freely changed. In the fourth shaft member 46, when the first leg portion 32 and the second leg portion 33 are fixed to the welding plate material 12, the second vibrating body 23 is attached to the welding plate material 12 (particularly, the material to be welded 13 on the far side). (state shown in FIG. 3). The second vibrating body 23 is a vibrating body that applies an impact to the material to be welded 13 on the far side (that is, the first material to be welded 13).

A sensor section 24 is attached to the second shaft member 39 and the third shaft member 43 . The sensor section 24 includes a first sensor section 25 attached to the second shaft member 39 and a second sensor section 26 attached to the third shaft member 43 .
The first sensor unit 25 includes a first sensor holder (first holder) 51 connected to the second shaft member 39 and a first vibration sensor (first sensor) 54 attached to the first sensor holder 51. I have. The second sensor unit 26 includes a second sensor holder (second holder) 52 connected to the third shaft member 43 and a second vibration sensor (second sensor) 55 attached to the second sensor holder 52. I have.

The second shaft member 39 has an upper second upper shaft 39a and a lower second lower shaft 39b that extend on the same straight line. The second upper shaft 39 a is inserted through the second guide 38 . A second flange 39c is formed at the upper end of the second upper shaft 39a. The second flange 39 c prevents the second shaft member 39 from slipping out of the second guide 38 due to an impact or the like from the first vibrating body 22 or the second vibrating body 23 .
The second upper shaft 39 a and the second lower shaft 39 b are connected by a second movable member 57 . The second movable member 57 finely adjusts the angle of the second lower shaft 39b with respect to the second upper shaft 39a. For example, a universal joint can be used as the second movable member 57 . A first sensor holder 51 is connected to the lower end of the second lower shaft 39b.
A first holder magnet member 61 is attached to the lower end of the first sensor holder 51 . The second shaft member 39 is positioned at the first position of the first sensor holder 51 when the first leg portion 32 and the second leg portion 33 are fixed to the welding plate material 12 (specifically, the second material to be welded 14). The holder magnet member 61 has a length that contacts the welding plate material 12 .

The first sensor holder 51 is formed, for example, in a cylindrical shape. The first sensor holder 51 includes a first top plate 62 connected to the lower end of the second lower shaft 39b, a first bottom plate 63 facing the first top plate 62, a peripheral portion of the first top plate 62 and the first A first side wall 64 is provided to connect the peripheral edge of the bottom plate 63 .
The first bottom plate 63 is fixed by the first top plate 62 and the first side walls 64 . The first vibration sensor 54 is mounted on the upper surface of the first bottom plate 63 in the space formed by the first top plate 62 , the first bottom plate 63 and the first side walls 64 . That is, the first bottom plate 63 is provided at the bottom of the first vibration sensor 54 . The first side wall 64 has a height such that the first top plate 62 does not contact the upper surface of the first vibration sensor 54 . The first sensor holder 51 supports the first vibration sensor 54 with the upper surface of the first vibration sensor 54 released.
Therefore, the pressing force of the first vibration sensor 54 can be managed to move up and down. Thereby, the measurement accuracy of the first vibration sensor 54 can be satisfactorily ensured.

The first vibration sensor 54 detects the vibration from the first material to be welded 13 to the second material to be welded in a state where the impact is applied from the first vibrating body 22 to the material to be welded 13 (first material to be welded 13) on the far side. A first vibration intensity of the shock wave propagated through the welded portion 15 to the welded material 14 is measured. In addition, the first vibration sensor 54 transmits the impact to the first material to be welded 13 in a state where the impact is applied from the second vibrating body 23 to the material to be welded 13 on the far side (first material to be welded 13). A second vibration intensity of the shock wave is measured (see FIG. 3).
The first vibration sensor 54 has a frequency band capable of measuring the impact from the first vibrating body 22 or the second vibrating body 23, and has a measurement frequency of 10 Hz to 15 kHz, for example. Also, the first vibration sensor 54 preferably has a measurement range of about 1000 mV.
The first vibration sensor 54 (first sensor holder 51) is connected to the second shaft member 39 on the surface side of the stage 34 by a second movable member 57 so that the joint angle can be freely changed.

A first holder magnet member 61 is provided on the lower surface of the first bottom plate 63 of the first sensor holder 51 . The first holder magnet member 61 is attracted to the welding plate material 12 (the material to be welded 14 ), and brings the first sensor holder 51 into close contact with the welding plate material 12 . Note that the first sensor holder 51 may directly contact the welding plate material 12 without providing the first holder magnet member 61 on the lower surface of the first bottom plate 63 .
The first sensor holder 51 is brought into close contact with the welding plate material 12 by the magnetic force of the first holder magnet member 61 .

The third shaft member 43 has an upper third upper shaft 43a and a lower third lower shaft 43b extending on the same straight line. The third upper shaft 43 a is inserted through the third guide 42 . A third flange 43c is formed at the upper end of the third upper shaft 43a. The third flange 43 c prevents the third shaft member 43 from slipping out of the third guide 42 due to an impact or the like from the first vibrating body 22 or the second vibrating body 23 .
The third upper shaft 43 a and the third lower shaft 43 b are connected by a third movable member 66 .
The third movable member 66 finely adjusts the angle of the third lower shaft 43b with respect to the third upper shaft 43a. A universal joint, for example, can be used as the third movable member 66 . A second sensor holder 52 is connected to the lower end of the third lower shaft 43b.
A second holder magnet member 67 is attached to the lower end of the second sensor holder 52 . The third shaft member 43 is positioned at the second position of the second sensor holder 52 when the first leg portion 32 and the second leg portion 33 are fixed to the welding plate material 12 (specifically, the first material to be welded 13). The holder magnet member 67 has a length that contacts the welding plate material 12 .

Like the first sensor holder 51, the second sensor holder 52 is, for example, cylindrical. The second sensor holder 52 includes a second top plate 71 connected to the lower end of the third lower shaft 43b, a second bottom plate 72 facing the second top plate 71, a peripheral portion of the second top plate 71 and the second bottom plate 72. A second side wall 73 is provided to connect the peripheral edge of the bottom plate 72 .
The second bottom plate 72 is fixed by the second top plate 71 and the second side walls 73 . A second vibration sensor 55 is mounted on the upper surface of the second bottom plate 72 in the space formed by the second top plate 71 , the second bottom plate 72 , and the second side walls 73 . That is, a second bottom plate 72 is provided at the bottom of the second vibration sensor 55 . The second side wall 73 has a height such that the second top plate 71 does not contact the upper surface of the second vibration sensor 55 . That is, the second sensor holder 52 supports the second vibration sensor 55 with the upper surface of the second vibration sensor 55 released.
Therefore, the pressing force of the second vibration sensor 55 can be managed to move up and down. Thereby, the measurement accuracy of the second vibration sensor 55 can be favorably secured.

The second vibration sensor 55 measures the vibration of the shock wave propagated to the first material to be welded 13 in a state where the first material to be welded 13 (the first material to be welded 13) on the far side is subjected to an impact from the first vibrating body 22. A second vibration intensity is measured. Further, the second vibration sensor 55 detects the vibration from the first material to be welded 13 to the second material to be welded in a state in which the impact is applied from the second vibrating body 23 to the material to be welded 13 (first material to be welded 13) on the far side. The first vibration intensity of the shock wave propagated through the welded portion 15 to the material 14 to be welded is measured (see FIG. 3).
Like the first vibration sensor 54, the second vibration sensor 55 has a frequency band capable of measuring the impact from the first vibrating body 22 or the second vibrating body 23. For example, the measurement frequency is 10 Hz to 15 kHz. have Also, the second vibration sensor 55 preferably has a measurement range of about 1000 mV.
The second vibration sensor 55 (second sensor holder 52) is connected to the third shaft member 43 on the surface side of the stage 34 by a third movable member 66 so that the joint angle can be freely changed.

A second holder magnet member 67 is provided on the lower surface of the second bottom plate 72 of the second sensor holder 52 . The second holder magnet member 67 adheres to the welding plate material 12 (the material to be welded 13 ) and brings the second sensor holder 52 into close contact with the welding plate material 12 . The second sensor holder 52 may directly contact the welding plate material 12 without providing the second holder magnet member 67 on the lower surface of the second bottom plate 72 .
The second vibration sensor 55 and the second holder magnet member 67 are mounted on the second holder magnet member 67 by bolts (not shown) that are inserted from the lower surface side of the second holder magnet member 67 and pass through the second holder magnet member 67 and the second bottom plate 72 . It is fixed to the bottom plate 72 .
Further, a metal such as aluminum is provided as a resin sheet or a flexible second sheet member 69 on the lower surface of the second holder magnet member 67 . In other words, the second sheet member 69 is arranged at the tip of the second vibration sensor 55 .
As a result, even when the welding plate material 12 (specifically, the first material to be welded 13) has an uneven surface, the contact area of the second sheet member 69 with respect to the first material to be welded 13 is can be ensured. Thereby, the measurement accuracy of the second vibration sensor 55 can be favorably secured.
Also, the center-to-center distance between the second vibrating body 23 and the second vibration sensor 55 may be longer than the leg length of the welded portion 15 . Furthermore, the center-to-center distance between the first vibration sensor 54 and the second vibration sensor 55 should be longer than the leg length of the welded portion 15 .

An electric slider 30 and a slider support shaft 75 are provided above the stage 34 . The electric slider 30 is fixed at a position in the height direction of the welding plate material 12 by a fixing member (not shown). The electric slider 30 has a slider shaft 30 a that can be extended and contracted in the vertical direction. The slider movable member 76 finely adjusts the angle of the slider support shaft 75 with respect to the slider shaft 30a. As the slider movable member 76, for example, a universal joint can be used. A lower end of the slider support shaft 75 is connected to the upper surface of the stage 34 .
That is, the slider support shaft 75 supports the stage 34 so as to be vertically movable with respect to the first material to be welded 13 and the second material to be welded 14 . The first sensor holder 51 and the second sensor holder 52 are moved vertically by extending and retracting the slider shaft 30a by the electric slider 30 to move the stage 34 vertically.

Here, the positional relationship among the first vibration sensor 54, the second vibration sensor 55, the first vibrating body 22, and the second vibrating body 23 will be described with reference to FIGS. 2 and 3. FIG.
As shown in FIG. 2 , the first vibrating body 22 and the second vibration sensor 55 are arranged so as to be mountable on the first material to be welded (the material to be welded on the far side) 13 . The second vibrating body 23 and the first vibration sensor 54 are arranged so as to be mountable on the second material to be welded (material to be welded on the front side) 14 .
A straight line L1 connecting the first vibrating body 22 and the first vibration sensor 54 and a straight line L2 connecting the first vibrating body 22 and the second vibration sensor 55 preferably extend so as to intersect each other. Moreover, it is preferable that the distance from the first vibrating body 22 to the first vibration sensor 54 and the distance from the first vibrating body 22 to the second vibration sensor 55 are set to be the same.

In this state, the first vibration sensor 54 detects vibration from the first material to be welded 13 in a state in which an impact is applied from the first vibrating body 22 to the material to be welded 13 (first material to be welded 13) on the far side. A first vibration intensity of the shock wave propagated through the welded portion 15 to the second material 14 to be welded is measured.
In addition, the second vibration sensor 55 propagates to the first material to be welded 13 in a state where the impact is applied from the first vibrating body 22 to the material to be welded 13 (first material to be welded 13) on the far side. A second vibration intensity of the shock wave is measured.

As shown in FIG. 3 , the first vibrating body 22 and the second vibration sensor 55 are arranged so as to be mountable on the second material to be welded (material to be welded on the front side) 14 . The second vibrating body 23 and the first vibration sensor 54 are arranged so as to be mountable on the first material to be welded 13 .
A straight line L3 connecting the second vibrating body 23 and the second vibration sensor 55 and a straight line L4 connecting the second vibrating body 23 and the first vibration sensor 54 preferably extend so as to intersect each other. Moreover, it is preferable that the distance from the second vibrating body 23 to the second vibration sensor 55 and the distance from the second vibrating body 23 to the first vibration sensor 54 are set to be the same.

In this state, the second vibration sensor 55 detects vibration from the first material to be welded 13 in a state in which the impact is applied from the second vibrating body 23 to the material to be welded 13 (first material to be welded 13) on the far side. A first vibration intensity of the shock wave propagated through the welded portion 15 to the second material 14 to be welded is measured.
In addition, the first vibration sensor 54 transmits the impact to the first material to be welded 13 in a state where the impact is applied from the second vibrating body 23 to the material to be welded 13 on the far side (first material to be welded 13). A second vibration intensity of the shock wave is measured.

Returning to FIG. 1 , the first vibrating body 22 , the first magnet member 32 b of the first leg 32 , and the second holder magnet member 67 of the second sensor holder 52 come into contact with the first material 13 to be welded. Also, the second vibrating body 23 , the second magnet member 33 b of the second leg portion 33 , and the first holder magnet member 61 of the first sensor holder 51 come into contact with the second material to be welded 14 .
In this state, the electric slider 30 contracts the slider shaft 30a, so that the stage 34 slides upward, and the first magnet member 32b of the first leg 32 and the second magnet member 33b of the second leg 33 move. separates from the welding plate material 12. The electric slider 30 further contracts the slider shaft 30 a to slide the stage 34 further upward, so that the first flange 36 c of the first shaft member 36 contacts the upper end of the first guide 35 . Also, the second flange 39 c of the second shaft member 39 contacts the upper end of the second guide 38 . Furthermore, the third flange 43 c of the third shaft member 43 contacts the upper end of the third guide 42 . Additionally, the fourth flange 46 c of the fourth shaft member 46 contacts the upper end of the fourth guide 44 .

From this state, the electric slider 30 further contracts the slider shaft 30a to slide the stage 34 further upward. Thereby, the first vibrating body 22 is separated from the first material to be welded 13 . Also, the first holder magnet member 61 of the first sensor holder 51 is separated from the second material to be welded 14 . Further, the second holder magnet member 67 of the second sensor holder 52 is separated from the first material 13 to be welded. In addition, the second vibrating body 23 separates from the second material to be welded 14 .

When the first vibrating body 22, the first magnet member 32b, the second magnet member 33b, the first holder magnet member 61, the second holder magnet member 67, and the second vibrating body 23 are separated from the welding plate material 12, the electric slider 30 extends the slider shaft 30a. As a result, the stage 34 slides downward, and the first vibrating body 22, the first holder magnet member 61, the second holder magnet member 67, and the second vibrating body 23 move toward the first magnet member 32b and the second magnet member 32b. It contacts the welding plate material 12 before 33b.
The first shaft member 36 , the second shaft member 39 , the third shaft member 43 , and the fourth shaft member 46 are vertically attached to the first guide 35 , the second guide 38 , the third guide 42 , and the fourth guide 44 . It is inserted so as to be slidable in the direction. As a result, the stage 34 can be slid further downward while the first vibrating body 22 , the first holder magnet member 61 , the second holder magnet member 67 , and the second vibrating body 23 are in contact with the welding plate material 12 . .
As a result, it is possible to reduce the disturbance of the waveforms indicating the first and second vibration intensities measured by the first vibration sensor 54 and the second vibration sensor 55, and to efficiently inspect a huge number of inspection points. can.

The first material to be welded 13 and the second material to be welded 14 are fillet welded at the welded portion 15 at the ends 13 a and 14 a to form the welded plate material 12 . The welded plate material 12 is used, for example, as a bottom plate of an oil tank.
The first material to be welded 13 and the second material to be welded 14 are carbon steel plate materials, but are not limited to this, and may be other weldable metal materials. In addition, although the size of the first material to be welded 13 and the second material to be welded 14 is, for example, 1.2 m long x 1 m wide x 9 mm thick, it is not limited to this. Other sizes are also possible.

In inspecting the throat thickness of the welded portion 15 of the first weld material 13 and the second weld material 14, welding is performed on the first weld material 13 and the second weld material 14 to be inspected. The inspection unit 20 of the unit inspection device 10 is arranged. First, the first vibrating body 22 and the second vibration sensor 55 are arranged on the surface of the first material 13 to be welded, and the second vibrating body 23 and the first vibration sensor 54 are arranged on the surface of the second material 14 to be welded. do.
Next, the first leg portion 32 is placed on the surface of the first material to be welded 13 so as to match the positions of the first vibrating body 22 , the first vibration sensor 54 , the second vibration sensor 55 and the second vibrating body 23 . , the second leg 33 is placed on the surface of the second material 14 to be welded. The second material to be welded 14 is arranged at a position higher than the first material to be welded 13 by being superimposed on the first material to be welded 13 . By adjusting the height of the second leg portion 33 with the second slider 33a, the stage 34 is arranged as horizontally as possible.

First vibrating body 22, first vibration sensor 54, second vibration sensor 55, and second vibrating body 23
are arranged in a direction perpendicular to the weld line of the welded portion 15 . It is more preferable to dispose the first vibration sensor 54 and the second vibration sensor 55 at substantially line-symmetrical positions with respect to the weld line of the welded portion 15 . Also, it is preferable to dispose the second vibrating body 23 in the vicinity of the first vibration sensor 54 . Furthermore, it is preferable to arrange the first vibrating body 22 in the vicinity of the second vibration sensor 55 .

In Embodiment 1, the first upper shaft 36 a and the first lower shaft 36 b are connected by the first movable member 45 . Therefore, even if the stage 34 through which the first upper shaft 36a is inserted is displaced from the horizontal state, the first workpiece can be welded by finely adjusting the angle of the first lower shaft 36b with respect to the first upper shaft 36a. The first vibrating body 22 can be installed so that the contact area with 13 is widened. In other words, the first vibrating body 22 can be installed horizontally. Therefore, the unevenness (error) of the applied impact value can be suppressed.

Also, the second upper shaft 39 a and the second lower shaft 39 b are connected by a second movable member 57 . Therefore, even if the stage 34 through which the second upper shaft 39a is inserted deviates from the horizontal state, the second workpiece 14 can be welded by finely adjusting the angle of the second lower shaft 39b with respect to the second upper shaft 39a. The first vibration sensor 54 can be installed so that the contact area with is widened. Therefore, the detection error of the detected vibration intensity can be reduced.

Furthermore, the third upper shaft 43 a and the third lower shaft 43 b are connected by a third movable member 66 . Therefore, even if the stage 34 through which the third upper shaft 43a is inserted deviates from the horizontal state, the first workpiece 13 can be welded by finely adjusting the angle of the third lower shaft 43b with respect to the third upper shaft 43a. The second vibration sensor 55 can be installed so that the contact area with is widened. Therefore, the detection error of the detected vibration intensity can be reduced.

In addition, the fourth upper shaft 46 a and the fourth lower shaft 46 b are connected by a fourth movable member 49 . Therefore, even if the stage 34 through which the fourth upper shaft 46a is inserted is displaced from the horizontal state, the second workpiece can be welded by finely adjusting the angle of the fourth lower shaft 46b with respect to the fourth upper shaft 46a. The second vibrating body 23 can be installed so that the contact area with 14 is widened. In other words, the second vibrating body 23 can be installed horizontally. Therefore, the unevenness (error) of the applied impact value can be suppressed.

A power cable for driving the first vibrating body 22, the second vibrating body 23, and the electric slider 30, and a measuring cable for the first vibration sensor 54 and the second vibration sensor 55 are provided on the stage 34, not shown, for example. The connector may be connected to the inspection control section 80 . By removing the cable, the inspection unit 20 and the inspection control unit 80 can be separately carried.

1 and 2, the first vibrating body 22 and the second vibration sensor 55 are arranged on the first material 13 to be welded, and the second vibrating body 23 and the first vibration sensor 55 are arranged on the second material 14 to be welded. Although the vibration sensor 54 is arranged, it is not limited to this. As another example, as described with reference to FIG. A first vibration sensor 54 may be arranged. Alternatively, the first and second legs 32, 33 may be removed.

As shown in FIG. 1, the inspection control unit 80 mainly has a control computer 81, a memory 82, an interface (I/F) circuit 83, a control circuit 84, and a storage device 85 such as a magnetic disk. The control computer 81, memory 82, I/F circuit 83, control circuit 84, and storage device (an example of storage unit) 85 are connected to each other via a bus (not shown).

A measurement unit 87 and a calculation unit 88 are arranged in the control computer 81 . The measurement unit 87 and the calculation unit 88 may be configured by software, or may be configured by hardware such as an electronic circuit. Alternatively, it may be a combination of these. Input data necessary for the control computer 81 or results of calculation are stored in the memory 82 each time. Moreover, when at least one of the measurement unit 87 and the calculation unit 88 is configured by software, a processing device such as a CPU or GPU is arranged.

As shown in FIG. 4, the control circuit 84 includes a calculator unit 91, a first DC component remover 92, a first amplifier 93, a second DC component remover 94, a second amplifier 95, and a first vibrator drive circuit 96. , and a second vibrator drive circuit 97 .
Calculator unit 91 includes acquisition section 101 , T0 calculation section 102 , V0 calculation section 103 , memory 104 and control section 105 . The acquisition unit 101, the T0 calculation unit 102, the V0 calculation unit 103, and the control unit 105 may be configured by software, or may be configured by hardware such as an electronic circuit. Alternatively, it may be a combination of these. The input data required for the calculator unit 91 or the calculated results are stored in the memory 104 each time. Further, when at least one of the acquisition unit 101, the T0 calculation unit 102, the V0 calculation unit 103, and the control unit 105 is configured by software, a processing device such as a CPU or GPU is arranged.

Note that the weld inspection apparatus 10 may include not only the specific configurations shown in FIGS. 1 to 4, but also other normally required configurations.

(Weld part inspection method)
Next, a weld inspection method for inspecting the throat thickness of the weld 15 of the first workpiece 13 and the second workpiece 14 by the weld inspection apparatus 10 will be described.
First, a first weld zone inspection method for inspecting the throat thickness of the weld zone 15 by applying an impact with the first vibrator 22 of the weld zone inspection apparatus 10 is shown in the flow charts of FIGS. 1, 2, 4 and 5. will be explained based on
As shown in FIGS. 1, 2, 4, and 5, the weld inspection apparatus 10 includes a command transmission step (S1), an impact application step (S2), a vibration strength measurement step (S3), and a DC component removal step. (S4) is executed. Further, the weld inspection apparatus 10 executes a shock wave profile acquisition step (S5), a peak time calculation step (S6), a peak voltage calculation step (S7), and a vibration strength ratio calculation step (S8).

In the command transmission step ( S<b>1 ), the measurement section 87 transmits a measurement start command to the control circuit 84 . Within the control circuit 84, a calculator unit 91 inputs a measurement start command. Then, the control section 105 in the calculator unit 91 outputs to the first vibrator driving circuit 96 a signal instructing the application of the impact.

In the impact applying step ( S<b>2 ), the first vibrating body drive circuit 96 drives the first vibrating body 22 to apply impact to the first weld material 13 . The first vibrating body drive circuit 96 sets 0 V during the measurement start time 0 to T1, and applies a voltage to the first vibrating body 22 for driving the first vibrating body 22 during the subsequent time T1 to T2.
The impact should be applied once. If the sound velocity of the iron plate is 5950 m/s, for example, the wavelength of 15 kHz is about 40 cm. long enough. This makes it possible to detect waves that have propagated through the entire weld. Therefore, one shock wave is enough to detect the wave that has propagated through the entire welded portion.

However, it is not limited to this, and multiple impacts may be applied. When multiple impacts are applied, it is preferable to apply them after the previous shock wave has attenuated. Moreover, the impact load applied by the first vibrating body 22 is preferably such that the first vibration sensor 54 and the second vibration sensor 55 can obtain a vibration strength of about several 100 mV. However, it is not limited to this, and may be appropriately set according to the performance of the first vibration sensor 54 and the second vibration sensor 55 .

In the vibration intensity measurement step (S3), the first vibration sensor 54 propagates from the first weld material 13 to the second weld material 14 via the welded portion 15 due to the impact on the first weld material 13. A first vibration intensity of the shock wave is detected (measured). The first vibration sensor 54 detects the first vibration intensity of the shock wave between times T1 and T2 described above. As a result, measurement errors due to time lag can be prevented. The detection result of the first vibration sensor 54 is output to the first amplifier 93 and amplified.
At the same time, second vibration sensor 55 detects (measures) the second vibration intensity of the shock wave propagated to first weld material 13 due to the impact on first weld material 13 . The second vibration sensor 55 detects the second vibration intensity of the shock wave between times T1 and T2 described above. As a result, measurement errors due to time lag can be prevented. The detection result of the second vibration sensor 55 is output to the second amplifier 95 and amplified.

In the DC component removing step ( S<b>4 ), the first DC component removing unit 92 removes the DC component from the detection result of the first vibration sensor 54 output from the first amplifier 93 .
Also, the second DC component removing section 94 removes the DC component from the detection result of the second vibration sensor 55 output from the second amplifier 95 .

In the shock wave profile acquisition step ( S<b>5 ), the acquisition unit 101 acquires the shock wave profile of the first vibration sensor 54 from the first DC component removal unit 92 .
The acquisition unit 101 also acquires the shock wave profile of the second vibration sensor 55 from the second DC component removal unit 94 .

In the peak time calculation step (S6), the T0 calculation unit 102 calculates the time T0 from the measurement start (T1) time to the peak (maximum value) A time of the measured vibration intensity. Alternatively, the time from a certain reference time may be calculated.
Here, from the time-series data of the vibration intensity (voltage) of the detection result of the first vibration sensor 54 obtained in the sampling period, the time of the maximum voltage of the first vibration sensor 54 (or the time from the start of measurement (T1)) time).
Also, from the time-series data of the vibration intensity (voltage) of the detection result of the second vibration sensor 55 obtained in the sampling period, the time of the maximum voltage of the second vibration sensor 55 (or the time from the start of measurement (T1)) ).

In the peak voltage calculation step (S7), the V0 calculation unit 103 calculates the peak voltage V0 (maximum voltage) of the measured vibration intensity corresponding to the time T0 in the detection result of the first vibration sensor 54. The calculated peak voltage V0 is output to the control computer 81 as the first peak voltage V0 of the first vibration sensor 54. FIG.
In addition, the V0 calculation unit 103 calculates the peak voltage V0 (maximum voltage) of the measured vibration intensity corresponding to the time T0 in the detection result of the second vibration sensor 55 . The calculated peak voltage V0 is output to the control computer 81 as the second peak voltage V0 of the second vibration sensor 55. FIG.

In the vibration intensity ratio calculation step (S8), the calculation unit 88 calculates the [vibration intensity ratio] between the [second peak voltage V0 of the second vibration sensor 55] and the [first peak voltage V0 of the first vibration sensor 54]. Calculate. i.e.
[Vibration intensity ratio]=[first peak voltage V0]/[second peak voltage V0]
to calculate
Here, for example, prior to the inspection, experiments are performed in advance using a plurality of test pieces having different throat thicknesses of the welds, and as correlation data, correlation data (for example, approximate (or the coefficients of the approximation formula) is stored in the storage device 85 as a calibration curve.
The throat thickness of the welded portion 15 is calculated (inspected) by substituting the [vibration intensity ratio] for the correlation data stored in the storage device 85 . The throat thickness of weld 15 is an example of an inspection parameter. A calculation result is output to a display device (for example, a monitor) (not shown) via the I/F circuit 83 . The output throat thickness is used to determine whether the welded portion 15 can be used (safety).

Next, a second weld inspection method for inspecting the throat thickness of the weld 15 by applying an impact with the second vibrator 23 of the weld inspection apparatus 10 will be described with reference to the flow charts of FIGS. will be explained based on
As shown in FIGS. 1 and 3 to 5, the measurement section 87 transmits a measurement start command to the control circuit 84 in the command transmission step (S1). Within the control circuit 84, a calculator unit 91 inputs a measurement start command. Then, the control section 105 in the calculator unit 91 outputs to the second vibrator driving circuit 97 a signal instructing the application of the impact.

In the impact applying step ( S<b>2 ), the second vibrating body drive circuit 97 drives the second vibrating body 23 to apply impact to the first weld material 13 . The second vibrating body drive circuit 97 sets 0 V from time 0 to T1 when the measurement is started, and applies a voltage to the second vibrating body 23 for driving the second vibrating body 23 from time T1 to T2 thereafter.
The impact should be applied once. If the sound velocity of the iron plate is 5950 m/s, for example, the wavelength of 15 kHz is about 40 cm. long enough. This makes it possible to detect waves that have propagated through the entire weld. Therefore, one shock wave is enough to detect the wave that has propagated through the entire welded portion.

However, it is not limited to this, and multiple impacts may be applied. When multiple impacts are applied, it is preferable to apply them after the previous shock wave has attenuated. Moreover, the impact load applied by the second vibrating body 23 is preferably such that the first vibration sensor 54 and the second vibration sensor 55 can obtain a vibration strength of about several 100 mV. However, it is not limited to this, and may be appropriately set according to the performance of the first vibration sensor 54 and the second vibration sensor 55 .

In the vibration intensity measurement step (S3), the second vibration sensor 55 propagates from the first weld material 13 to the second weld material 14 via the welded portion 15 due to the impact on the first weld material 13. A first vibration intensity of the shock wave is detected (measured). The second vibration sensor 55 detects the first vibration intensity of the shock wave between times T1 and T2 described above. As a result, measurement errors due to time lag can be prevented. The detection result of the second vibration sensor 55 is output to the first amplifier 93 and amplified.
At the same time, first vibration sensor 54 detects (measures) the second vibration intensity of the shock wave propagated to first weld material 13 due to the impact on first weld material 13 . The first vibration sensor 54 detects the second vibration intensity of the shock wave between times T1 and T2 described above. As a result, measurement errors due to time lag can be prevented. The detection result of the first vibration sensor 54 is output to the second amplifier 95 and amplified.

In the DC component removing step ( S<b>4 ), the first DC component removing section 92 removes the DC component from the detection result of the second vibration sensor 55 output from the first amplifier 93 .
Also, the second DC component removing section 94 removes the DC component from the detection result of the first vibration sensor 54 output from the second amplifier 95 .

In the shock wave profile acquisition step ( S<b>5 ), the acquisition unit 101 acquires the shock wave profile of the second vibration sensor 55 from the first DC component removal unit 92 .
The acquisition unit 101 also acquires the shock wave profile of the first vibration sensor 54 from the second DC component removal unit 94 .

In the peak time calculation step (S6), the T0 calculation unit 102 calculates the time T0 from the measurement start (T1) time to the peak (maximum value) A time of the measured vibration intensity. Alternatively, the time from a certain reference time may be calculated.
Here, from the time-series data of the vibration intensity (voltage) of the detection result of the second vibration sensor 55 obtained in the sampling period, the time of the maximum voltage of the second vibration sensor 55 (or the time from the start of measurement (T1)) time).
Also, from the time-series data of the vibration intensity (voltage) of the detection result of the first vibration sensor 54 obtained in the sampling period, the time of the maximum voltage of the first vibration sensor 54 (or the time from the start of measurement (T1)) ).

In the peak voltage calculation step (S7), the V0 calculation unit 103 calculates the peak voltage V0 (maximum voltage) of the measured vibration intensity corresponding to the time T0 in the detection result of the second vibration sensor 55. The calculated peak voltage V0 is output to the control computer 81 as the first peak voltage V0 of the second vibration sensor 55. FIG.
In addition, the V0 calculation unit 103 calculates the peak voltage V0 (maximum voltage) of the measured vibration intensity corresponding to the time T0 in the detection result of the first vibration sensor 54 . The calculated peak voltage V0 is output to the control computer 81 as the second peak voltage V0 of the first vibration sensor 54. FIG.

In the vibration intensity ratio calculation step (S8), the calculation unit 88 calculates the [vibration intensity ratio] between the [second peak voltage V0 of the first vibration sensor 54] and the [first peak voltage V0 of the second vibration sensor 55]. Calculate. i.e.
[Vibration intensity ratio]=[first peak voltage V0]/[second peak voltage V0]
to calculate
Here, for example, prior to the inspection, experiments are performed in advance using a plurality of test pieces having different throat thicknesses of the welds, and as correlation data, correlation data (for example, approximate (or the coefficients of the approximation formula) is stored in the storage device 85 as a calibration curve.
The throat thickness (an example of an inspection parameter) of the welded portion 15 is calculated by substituting the [vibration intensity ratio] for the correlation data stored in the storage device 85 . A calculation result is output to a display device (for example, a monitor) (not shown) via the I/F circuit 83 . The output throat thickness is used to determine whether the welded portion 15 can be used (safety).

As described above, according to the weld inspection apparatus 10, the first weld inspection method of applying an impact to the first vibrating body 22 and the second method of applying an impact to the second vibrating body 23 of the weld inspection apparatus 10 The throat thickness of the welded portion 15 can be inspected in the two methods of inspecting the welded portion.

As described above, according to the weld inspection apparatus 10 of the first embodiment, it is possible to reduce the disturbance of the waveforms indicating the first and second vibration intensities measured by the first vibration sensor 54 and the second vibration sensor 55. In addition, a huge number of inspection points can be efficiently inspected.

(running device)
As shown in FIGS. 6 and 7, the weld inspection apparatus 10 of Embodiment 1 further includes a travel device 200. As shown in FIGS. The weld inspection apparatus 10 is used, for example, in a cylindrical oil tank 300 (see FIG. 8) to automatically inspect many welds 15 of the bottom plate 301 of the oil tank 300 . That is, the welded portion inspection apparatus 10 of the first embodiment moves to a predetermined inspection area of the welded portion 15 of the bottom plate 301 in the oil tank 300 by the travel device 200, and inspects the welded portion 15 by the inspection portion 20. is.

As shown in FIG. 8, a bottom plate 301 of a petroleum tank 300 is welded at a welded portion 15 in a state in which a plurality of welded materials 303 to 308 are stacked outward from the center of the bottom plate in a stepped manner. A part of the bottom plate 301 is configured by, for example, the welding plate material 12 shown in FIG. The plurality of welded materials 303 to 308 are partially composed of, for example, the first welded material 13 and the second welded material 14 shown in FIG. 6 and 7, the bottom plate 301 of the oil tank 300 will be referred to as the welding plate material 12, the first material to be welded 13, and the second material to be welded. 14 may be described.

6 and 7, the traveling device 200 includes a traveling housing (housing) 212 that is rectangular in plan view, four wheels 214 that support the traveling housing 212 from below, and a battery 216. ing.
The four wheels 214 are composed of a first wheel 214a on one side and a second wheel 214b on the other side.
The traveling device 200 is configured to be able to travel (drivable) on the bottom plate 301 of the oil tank 300 in the longitudinal direction of the traveling housing 212 by means of the battery 216 at a speed of, for example, about 4 to 5 km/h. The bottom plate (for example, the welded plate material 12) of the oil tank is formed by, for example, welding the first welded material 13 and the second welded material 14 in a superimposed state at the welded portion 15. . Therefore, the surface of the second weld material 14 stacked on the upper side is arranged at a higher position than the surface of the first weld material 13 stacked on the lower side. In other words, the first material to be welded 13 is arranged at a position on the farther side than the second material to be welded 14 when viewed from the side where the welded portion 15 is detected. The second material to be welded 14 is arranged on the front side of the first material to be welded 13 when viewed from the side where the welded portion 15 is detected.

In a state in which the travel device 200 straddles the welded portions 15 of the first material to be welded 13 and the second material to be welded 14, the first wheel 214a on one side is arranged on the surface of the first material to be welded 13, The second wheel 214b on the other side is arranged on the surface of the two workpieces 14 to be welded. Therefore, it is conceivable that the first wheel 214a and the second wheel 214b are different in height, and the travel housing 212 is tilted. Therefore, the four wheels 214 (that is, the first wheel 214a and the second wheel 214b) are provided with independent suspensions (not shown) whose height can be adjusted independently with respect to the traveling housing 212. The independent suspension is controlled by a control device 230 (to be described later) to maintain horizontality of the travel housing 212 with respect to the surfaces of the first material 13 and the second material 14 to be welded. That is, the travel device 200 has a mechanism for keeping the stage 34 horizontal.

In addition, the weld inspection apparatus 10 of the first embodiment includes a lateral movement mechanism 218, a position detection sensor (position sensor) 219, a step detection sensor 221, an obstacle detection sensor (obstacle detection device) 222, a horizontal It includes a sensor 224, a headlight 226, a controller 230, and the like.
A lateral movement mechanism 218 , a position detection sensor 219 , a step detection sensor 221 , an obstacle detection sensor 222 , a horizontal sensor 224 , a headlight 226 and a control device 230 are mounted on the travel device 200 . The weld inspection device 10 has a size that allows it to pass through a manhole having a diameter of about 500 mm provided in, for example, an oil tank.

The lateral movement mechanism 218 is a mechanism for moving the inspection section 20 along the width direction of the traveling housing 212, that is, the lateral direction (width direction) orthogonal to the traveling direction. The lateral movement mechanism 218 is, for example, a slider member connected to a shaft 231 extending in the width direction of the traveling housing 212 and the electric slider 30 of the inspection unit 20 and configured to be movable along the shaft 231. 232 and a drive mechanism (not shown) that moves the slider member 232 along the shaft 231 . Both ends of the shaft 231 are supported on both side walls of the traveling housing 212 at the same height position.
However, the configuration of the lateral movement mechanism 218 is not limited to this. For example, it may be an electric slider provided on one side wall of the traveling housing 212 and configured to be expandable and contractable in the width direction of the traveling housing 212. . In this case, the electric slider of the inspection unit 20 may be connected to the tip of the slider shaft of the electric slider.

The position detection sensor 219 detects the position of the travel device 200 on the circular bottom plate 301 (two-dimensional) of the oil tank 300 (see FIG. 8). The step detection sensor 221 detects the step of the welded portion 15 of the first welded material 13 and the second welded material 14 to identify the position of the welded portion 15 . Further, the step detection sensor 221 detects the position of the welded material located on the far side when viewed from the side where the welded portion 15 is detected, among the first welded material 13 and the second welded material 14 that are stacked in a stepped manner. to detect.
As the step detection sensor 221, for example, a laser beam is scanned in the width direction of the travel housing 212 to measure the distance to the first material to be welded 13 and the distance to the second material to be welded 14. can be used.

The object-to-be-welded member determination unit 220 determines the material to be welded on the far side detected by the step detection sensor 221 . The hit target member determination section 220 is included in the control section 105 (see FIG. 4) in the calculator unit 91 . The control unit 105 instructs the first vibrating body driving circuit 96 or the second vibrating body driving circuit 97 (see FIG. 4) to apply an impact to the material to be welded on the far side determined by the impact target member determination unit 220. Outputs a signal that instructs to apply an impact. As a result, the throat thickness of the welded portion 15 can be inspected in the first welded portion inspecting method in which the impact is applied to the material to be welded on the far side with the first vibrating body 22 . Further, the throat thickness of the welded portion 15 can be inspected in the second welded portion inspection method in which the second vibration body 23 applies an impact to the material to be welded on the far side.

In this way, the hit target member determination unit 220 determines the back welding material (one welding material) of the back welding material and the front welding material. In addition, in the embodiment, an example in which the hitting target member determination unit 220 determines the material to be welded on the far side will be described, but the present invention is not limited to this. As another example, the hit target member determination unit 220 may determine the front side to-be-welded material (the other to-be-welded material). In this case, the throat thickness of the welded portion 15 is inspected by applying an impact to the material to be welded on the front side with the first vibrating body 22 or the second vibrating body 23 .
Further, the hit target member determination unit 220 detects the step of the welded portion 15 of the first welded material 13 and the second welded material 14 to determine the traveling direction of the welded portion inspection device 10 . Information for determining the travel direction of the weld inspection device 10 is input to the travel device control unit 260 .

The obstacle detection sensor 222 detects a structure or a person existing in the traveling direction of the travel device 200 . The bottom plate (welded plate material 12) of the oil tank is usually provided with a large number of struts for supporting the roof of the oil tank. When inspecting the bottom plate with the weld inspection device 10, the operator may be working on the bottom plate. An obstacle detection sensor 222 is mounted in order to avoid such pillars and workers existing in the traveling direction of the travel device 200 .

Horizontal sensor 224 is a sensor for detecting horizontality of traveling device 200 (shaft 231). Since the inside of the oil tank is usually dark, the travel housing 212 of the travel device 200 is provided with a headlight 226 for illuminating the direction of travel.
The control device 230 is provided in the travel device 200 and is a device for controlling the inspection section 20 , the lateral movement mechanism 218 , and the travel device 200 . The control device 230 includes a control circuit 84 , a lateral movement mechanism control section 250 , a traveling device control section 260 and a storage device 85 . The control circuit 84, the lateral movement mechanism control section 250, and the traveling device control section 260 may be configured by software, or may be configured by hardware such as an electronic circuit. Alternatively, it may be a combination of these.

As described above, the control circuit 84 controls the inspection unit 20 (see FIG. 1), specifically, the vibrating body 21, the sensor unit 24, and the electric slider 30, respectively.

The lateral movement mechanism control section 250 controls the lateral movement mechanism 218 based on the input from the step detection sensor 221 . The traveling device control unit 260 stores information about the target position on the bottom plate 301 stored in advance in the storage device 85 , the position of the traveling device 200 on the bottom plate 301 detected by the position detection sensor 219 , and the information from the obstacle detection sensor 222 . The traveling device 200 is controlled based on the input information. In addition, the traveling device control unit 260 controls the traveling device 200 based on information about the traveling direction of the weld zone inspection device 10 determined by the hitting target member determination unit 220 . As a result, the travel device 200 is moved to the target position.
Further, the traveling gear control unit 260 controls the independent suspension of the four wheels 214 based on the input from the horizontal sensor 224 so that the shaft 231 attached to the traveling gear 200 is horizontal.
The storage device 85 stores information on target positions (inspection target positions) on the bottom plate 301 as well as inspection results (parameter calculation results) for each inspection target position. There are approximately 50,000 target positions on the bottom plate 301 when inspecting a bottom plate with a diameter of 100 m at intervals of about 10 cm.

Further, the control device 230 includes a computing section 88 (see FIG. 1). When the lateral movement mechanism control section 250 controls the lateral movement mechanism 218 or when the traveling apparatus control section 260 controls the traveling device 200, the computing section 88 uses information stored in advance in the storage device 85, Based on the input information, necessary calculations are performed.

(bottom plate of oil tank)
As shown in FIG. 8, a bottom plate 301 of a petroleum tank 300 is welded at a welded portion 15 in a state in which a plurality of welded materials 303 to 308 are stacked outward from the center of the bottom plate in a stepped manner. Specifically, the inner portions 304a of the second material to be welded 304 are superimposed on the outer portions 303a on both sides of the first material to be welded 303 at the center of the bottom plate in a stepped manner from above, and are welded at the welded portion 15. . The inner part 305a of the third material to be welded 305 is welded to the outer part 304b of the second material to be welded 304 at the welding part 15 in a state of being superimposed from above in a stepped manner. The inner part 306a of the fourth material to be welded 306 is welded to the outer part 305b of the third material to be welded 305 at the welding part 15 in a state of being superimposed from above in a stepped manner.

In addition, the inner portion 307a of the fifth material to be welded 307 is superimposed on the outer ends 303b and 304c of the first material to be welded 303 and the second material to be welded 304 from above in a stepped manner, and the welding portion 15 is welded. ing.
The inner part 308a of the sixth material to be welded 308 is welded to the outer ends 305c and 306b of the third material to be welded 305 and the fourth material to be welded 306 at the welding part 15 in a stepped state from above. . Further, the inner end portions 308b of the sixth material to be welded 308 are superposed on the outer end portions 307b on both sides of the fifth material to be welded 307 from above in a stepped manner and are welded at the welding portion 15 .

(Method for inspecting welded portion of bottom plate)
Next, an automatic weld inspection method for automatically inspecting the weld 15 of the bottom plate 301 of the oil tank 300 by the weld inspection device 10 will be described with reference to the flow charts of FIGS. 6, 8 to 10 and 11. .
Specifically, as shown in FIG. 8, a method of automatically inspecting the welded portion 15 of the bottom plate 301 of the oil tank 300 in the order of arrow A, arrow B, and arrow C; A method for automatically inspecting in order will be described.
Hereinafter, among the welded materials stacked in a stepped manner, the welded material located on the back side as seen from the side where the welded portion 15 is detected is referred to as the "back side welded material", and the welded material located on the front side. is sometimes described as "the material to be welded on the front side".

As shown in FIGS. 6, 7 and 11, in the origin setting step (S20), for example, information about the origin on the bottom plate 301 of the oil tank 300 is set. Here, the origin is the position where the traveling device 200 starts traveling, and for example, the position where the charger for the battery 216 of the traveling device 200 is installed can be the origin.

In the target position movement step ( S<b>21 ), the traveling device 200 is caused to travel to the target position based on the previously obtained target position information and the position information of the traveling device 200 detected by the position detection sensor 219 . That is, the weld inspection device 10 moves in the direction of arrow A (see FIG. 8) along the weld line of the weld 15 and stops at inspection positions at regular intervals.
When the obstacle detection sensor 222 detects an obstacle while the traveling device 200 is traveling, the traveling device 200 is stopped or is caused to travel so as to avoid the obstacle. Once the target position is reached, the horizontal sensor 224 controls the independent suspension of the wheel 214 so that the shaft 231 attached to the traveling device 200 is horizontal.

In the inspection device installation step ( S<b>22 ), the control device 230 controls the driving mechanism of the lateral movement mechanism 218 based on the position information of the welded portion 15 input from the level difference detection sensor 221 . The slider member 232 of the lateral movement mechanism 218 is moved along the width direction of the travel housing 212 to above the welded portion 15 . This positions the inspection unit 20 connected to the lateral movement mechanism 218 at an appropriate position above the weld 15 .
That is, the first sensor holder 51 and the second sensor are positioned so that the position of the welded portion 15 specified by the step detection sensor 221 is positioned between the first vibrating body 22 and the first vibration sensor 54 (see FIG. 1). The holder 52 (see FIG. 1) is moved in the width direction.

As shown in FIGS. 8 and 9, the inspection unit 20 has a first vibrating body 22 and a second vibration sensor 55 arranged on a third material to be welded 305 on the back side, and a vibration sensor on a fourth material to be welded 306 on the front side. A second vibrating body 23 and a first vibration sensor 54 are arranged. Therefore, the first vibrating body 22 and the first vibration sensor 54 are arranged across the welded portion 15 . Also, the second vibrating body 23 and the second vibration sensor 55 are arranged across the welded portion 15 .
Next, by controlling the electric slider 30 to lower the stage 34, the first vibrating body 22 and the second vibration sensor 55 are installed on the surface of the third material to be welded 305 on the far side, and the second vibrating body 23 And the first vibration sensor 54 is installed on the front surface of the fourth material to be welded 306 . By controlling the electric slider 30 to further lower the stage 34 , the first leg 32 and the second leg 33 of the stage 34 are placed on the surface of the bottom plate 301 of the oil tank 300 .

Here, as shown in FIG. 1, the first vibration sensor 54 is supported by the first sensor holder 51 with the upper surface of the first vibration sensor 54 opened. Further, the second vibration sensor 55 is supported by the second sensor holder 52 with the upper surface of the second vibration sensor 55 opened. As a result, it is possible to control the pressing force of the first vibration sensor 54 and the second vibration sensor 55 and move up and down. As a result, the first vibration sensor 54 can be installed on the front surface of the fourth material to be welded 306 in a state in which the measurement accuracy of the first vibration sensor 54 and the second vibration sensor 55 is satisfactorily ensured. 55 can be installed on the surface of the third material to be welded 305 on the far side.

As shown in FIGS. 9 and 11, in the welded portion inspection step (S23), the hitting target member determination unit 220 (FIG. 7). The first vibrating body 22 is installed on the surface of the third material to be welded 305 on the far side. In this state, the weld zone inspection process shown in FIG. 5, that is, a series of processes from the command transmission process (S1) to the vibration intensity ratio calculation process (S8) are executed.
Here, the first vibrating body 22 is installed on the surface of the third material to be welded 305 on the far side. Therefore, in the command transmission step (S1) to the vibration strength ratio calculation step (S8), the first weld portion inspection method in which the first vibrating body 22 applies an impact to the third material to be welded 305 on the far side is applied to the weld portion 15. Check throat thickness.
Then, when the vibration intensity ratio calculation step (S8) is finished, the calculation result of the throat thickness (an example of the inspection parameter) of the welded portion 15 is stored together with the target position (inspection target position) information.

As shown in FIGS. 6, 9, and 11, in the inspection apparatus retracting step (S24), the electric slider 30 is controlled to raise the stage 34, so that the first leg 32 and the second leg of the stage 34 are 33 is pulled away from the surface of the bottom plate 301 of the oil tank 300 . After that, by controlling the electric slider 30 to further raise the stage 34 , the first vibrating body 22 , the second vibrating body 23 , the first vibration sensor 54 , and the second vibration sensor 55 are separated from the surface of the bottom plate 301 .
Next, the drive mechanism of the lateral movement mechanism 218 is controlled to move the slider member 232 of the lateral movement mechanism 218 along the width direction of the travel housing 212 . As a result, the inspection unit 20 is retracted to a position within the travel housing 212 that does not interfere with the travel of the travel device 200 .

Next, in the remaining battery level detection step (S25), the remaining amount of the battery 216 of the traveling device 200 is detected to determine whether charging is necessary. When it is determined that charging is necessary, the traveling device 200 is controlled to travel to the origin set in (S20), and the battery 216 is charged by the charger installed at the origin. On the other hand, if it is determined that charging is not necessary, control device 230 refers to a built-in timer (not shown) in (S26) to determine whether travel time of travel device 200 has passed a predetermined time. When determining that the predetermined time has elapsed, the traveling device control unit 260 controls the traveling device 200 to travel to the starting point set in (S20), and replaces the battery 216 at the starting point.

On the other hand, if it is determined that the predetermined time has not elapsed, the process proceeds to the inspection end determination step (S27). In the inspection end determination step (S27), the control device 230 refers to the storage device 85 to check whether the calculation results of the inspection parameters (throat thickness of the welded portion 15) are stored for all target positions. It is determined whether or not the inspection regarding the target position of is completed.
If it is determined that the inspection for all target positions has been completed, the process proceeds to the inspection result display step (S28). In the inspection result display step (S28), the control device 230 displays the inspection results for each target position on a display device (for example, a monitor) (not shown) via the I/F circuit 83 (see FIG. 1) of the inspection control unit 80, for example. Map the results.

In (S27), if it is determined that the inspection for all target positions has not been completed, the flow returns to the target position movement step (S21). In the target position movement step (S21), new target position information is acquired, and subsequent steps are sequentially executed for the new target position.
Specifically, the step of the welded portion 15 is detected by the hit target member determination unit 220 to determine the running direction of the welded portion inspection device 10 . Based on the information from the hitting target member determination unit 220 , the welded portion inspection device 10 is caused to travel in the direction of arrow A along the welded portion 15 by the travel device 200 to continuously inspect the welded portion 15 . After the inspection of the welded portion 15 in the direction of the arrow A is completed by the welded portion inspection device 10, the step of the welded portion 15 is detected by the hitting target member determination unit 220, and the welded portion inspection device 10 detects an arrow B (see also FIG. 8). determine the direction of travel. Based on the information from the hitting target member determination unit 220, the welded portion inspection device 10 is caused to travel in the direction of arrow B along the welded portion 15 by the travel device 200, and the welded portion 15 is continuously inspected.

When the weld inspection apparatus 10 is moved in the direction of the arrow B along the weld 15, the first vibrating body 22 and the second vibration sensor 55 are installed on the surface of the third material to be welded 305 on the far side. The second vibrating body 23 and the first vibration sensor 54 are installed on the surface of the sixth weld material 308 on the side. Therefore, similarly to the first weld inspection method in which the weld inspection apparatus 10 is moved in the direction of the arrow A along the weld 15 by the travel device 200, the first vibrator is applied to the third weld material 305 on the far side. The throat thickness of the weld 15 is checked by applying an impact at 22 .
After the inspection of the welded portion 15 in the direction of the arrow B is completed by the welded portion inspection device 10, the step of the welded portion 15 is detected by the hitting target member determination unit 220, and the welded portion inspection device 10 detects an arrow C (see also FIG. 8). determine the direction of travel.

As shown in FIGS. 6, 10, and 11, based on the information of the target member determination unit 220, the weld inspection device 10 is caused to travel in the direction of arrow C along the weld 15 by the travel device 200, thereby performing welding. Section 15 continues to be inspected.
When the weld inspection apparatus 10 is moved in the direction of arrow C along the weld 15, the second vibrating body 23 and the first vibration sensor 54 are installed on the surface of the second material to be welded 304 on the far side. The first vibrating body 22 and the second vibration sensor 55 are installed on the surface of the third weld material 305 on the side. Therefore, the throat thickness of the welded portion 15 is inspected by applying an impact to the second welded material 304 on the far side with the second vibrating body 23 in the same manner as in the second welded portion inspection method.
6 and 8, the welded portion 15 of the bottom plate 301 of the oil tank 300 can be automatically inspected by the welded portion inspection device 10 in the order of arrow A, arrow B, and arrow C. FIG.

Here, after inspecting the throat thickness of the welded portion 15 by traveling the welded portion inspection device 10 in the direction of the arrow B, the welded portion inspection device 10 is caused to travel in the direction of the arrow D along the welded portion 15 by the travel device 200. It is also possible to inspect the weld 15 continuously. That is, the weld inspection apparatus 10 is moved along the weld 15 in the direction of the arrow D and in the direction of the arrow B in the same manner as the first weld inspection method. The throat thickness of the welded portion 15 is inspected by applying an impact with the first vibrating body 22 .
As a result, the welded portion 15 of the bottom plate 301 of the oil tank 300 can be automatically inspected by the welded portion inspection device 10 in the order of arrow A, arrow B, and arrow D. FIG.

As described above, according to the weld inspection apparatus 10 of Embodiment 1, the weld inspection apparatus 10 automatically travels on the bottom plate 301 of the oil tank 300 by the travel device 200, for example, while the weld inspection apparatus 10 inspects the weld line of the weld 15. and stop at regular intervals. The throat thickness of the welded portion 15 can be inspected by moving up and down the sensor portion 24 (the first vibration sensor 54 and the second vibration sensor 55) (see FIG. 1) at the stopped position. As a result, a huge number of inspection points can be efficiently inspected.

As described above, according to the weld inspection apparatus 10 of the first embodiment, it is possible to reduce the disturbance of the waveforms indicating the first and second vibration intensities measured by the first vibration sensor 54 and the second vibration sensor 55. In addition, a huge number of inspection points can be efficiently inspected.

The first embodiment of the present invention has been described above. However, the invention is not limited to the above embodiments. On the bottom plate 301 of the oil tank 300, rust from the plate material forming the bottom plate 301, rust falling from the roof of the oil tank 300, and the like exist, which may affect the inspection result. Therefore, the travel device 200 may be further provided with an air blower for removing rust, dust, etc. present on the bottom plate 301 .

In the first embodiment, in the inspection device retracting step (S24), after the inspection unit 20 is separated from the bottom plate 301 of the oil tank 300, the lateral movement mechanism 218 is driven to move the inspection unit 20 away from the traveling device 200. I moved it to a position where it wouldn't get in the way. However, the present invention is not limited to this, and after separating the inspection unit 20 from the bottom plate 301 of the oil tank 300, the inspection unit 20 does not have to be moved in the width direction as long as the traveling of the traveling device 200 is not hindered.

In the first embodiment, when the control device 230 determines in (S26) that the predetermined time has elapsed, the traveling device control unit 260 controls the traveling device 200 to move the traveling device 200 to the starting point set in (S20). was run, and the battery 216 was replaced at the starting point. However, the present invention is not limited to this, and if the control device 230 determines in (S26) that the predetermined time has elapsed, a message indicating that the battery 216 needs to be replaced is displayed on a display device (not shown) via the I/F circuit 83, for example. You may By displaying on the display device that the battery 216 needs to be replaced, the worker is notified and the battery 216 is replaced on the spot without returning to the starting point.

In the first embodiment, in the target position movement step (S21), the traveling device 200 is moved to the target position based on the target position information acquired from the storage device 85 and the position information of the traveling device 200 detected by the position detection sensor 219. made it run. However, the present invention is not limited to this, and a weld line that is a continuation of the welded portion 15 of the bottom plate 301 of the oil tank 300 is detected by, for example, the step detection sensor 221, and along the weld line detected by the step detection sensor 221, the travel device 200 may be run.

<Embodiment 2>
Next, a weld inspection apparatus 400 of Embodiment 2 will be described with reference to FIGS. 12 and 13. FIG. In the weld inspection apparatus 400 of the second embodiment, the same or similar members as those of the weld inspection apparatus 10 of the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.
As shown in FIG. 12, the weld inspection apparatus 400 of the second embodiment is configured such that the second vibrating body 23 is removed from the weld inspection apparatus 10 of the first embodiment, and the stage 34 is rotatable. The configuration is the same as that of the weld inspection device 10 of the first embodiment.
The stage 34 is rotatably supported, for example, in the arrow E direction (clockwise direction) and the arrow F direction (counterclockwise direction) about the rotation shaft 402 . The stage 34 supports the first vibrating body 22 , the second vibration sensor 55 and the first vibration sensor 54 . Note that the stage 34 may be configured to rotate in either the arrow E direction or the arrow F direction.

According to the weld zone inspection apparatus 400 of the second embodiment, the first vibrating body 22 and the second vibration sensor 55 are installed on the first material to be welded 13 on the back side, and the first vibration sensor 54 is installed on the second front side. is installed on the material 14 to be welded. Welding is performed based on the first vibration intensity and the second vibration intensity measured by the first vibration sensor 54 and the second vibration sensor 55 by applying an impact to the first material to be welded 13 on the far side with the first vibrating body 22 . The throat thickness of the portion 15 is inspected.

As shown in FIG. 13( a ), according to the weld zone inspection apparatus 400 , the first vibrating body 22 and the second vibration sensor 55 are installed on the second material to be welded 14 on the front side, and the first vibration sensor 54 is installed on the first material to be welded 13 on the far side. In this case, the stage 34 is rotated in the direction of arrow E around the rotation shaft 402 .

As shown in FIG. 13B, by rotating the stage 34, the first vibrating body 22 and the second vibration sensor 55 are installed on the first material to be welded 13 on the far side, and the first vibration sensor 54 is It is installed on the second material to be welded 14 on the front side. Welding is performed based on the first vibration intensity and the second vibration intensity measured by the first vibration sensor 54 and the second vibration sensor 55 by applying an impact to the first material to be welded 13 on the far side with the first vibrating body 22 . The throat thickness of the portion 15 is inspected.

As described above, according to the weld inspection apparatus 400, by rotating the stage 34, the second vibrating body 23 is not supported by the stage 34, and, similarly to the weld inspection apparatus 10 of the first embodiment, for example, petroleum is detected. The weld 15 of the bottom plate 301 (see FIG. 8) of the tank 300 can be inspected. In other words, the welded portion 15 can be inspected while automatically running the welded portion inspection apparatus 400 of the second embodiment on the bottom plate 301 of the oil tank 300, for example. As a result, according to the weld inspection apparatus 400 of the second embodiment, similarly to the first embodiment, a huge number of inspection points can be efficiently inspected.
As described above, according to the weld zone inspection apparatus 400 of the second embodiment, it is possible to reduce the disturbance of the waveforms indicating the first and second vibration intensities measured by the first vibration sensor 54 and the second vibration sensor 55. In addition, a huge number of inspection points can be efficiently inspected.

The technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.
In Embodiments 1 and 2, one of the material to be welded on the back side and the material to be welded on the front side is used as the material to be welded on the back side, and an impact is applied to the material to be welded on the back side. Although an example of inspecting the throat thickness of the weld has been described, the present invention is not limited to this. As another example, one of the material to be welded on the far side and the material to be welded on the front side is used as the material to be welded on the front side. Thickness may be checked.

Reference numerals 10, 400 Weld zone inspection device 12 Welding plate material 13 First welded material (back side welded material, one welded material)
14... Second welded material (welded material on the front side, one welded material)
Reference Signs List 15 Welding portion 21 Vibrating bodies 22, 23 First and second vibrating bodies 24 Sensor portion 30 Electric slider (vertical movement mechanism)
34... Stage 51... First sensor holder (first holder)
52... Second sensor holder (second holder)
54... First vibration sensor (first sensor)
55... Second vibration sensor (second sensor)
85 ... storage device (storage unit)
88... Arithmetic unit 200... Travel device 212... Travel housing (housing)
214...Four wheels 214a...First wheel 214b on one side...Second wheel on the other side 216...Battery 218...Lateral movement mechanism 219...Position detection sensor (position sensor)
220 ... Strike target member determination unit 221 ... Level difference detection sensor 222 ... Obstacle detection sensor (obstacle detection device)
224...Horizontal sensor 226...Headlight 230...Control device 300...Oil tank 301...Bottom plate

Claims (11)

A welded portion inspection device for inspecting a welded portion in which a material to be welded on the back side and a material to be welded on the front side are welded in a stepped manner when viewed from the detection side,
an impact target member determination unit that determines one of the back side welding material and the front side welding material;
a vibrating body that applies an impact to the one welded material determined by the hit target member determination unit;
a first sensor for measuring a first vibration intensity of a shock wave propagated by the impact from one of the materials to be welded to the other material to be welded through the welded portion;
a second sensor for measuring a second vibration intensity of the shock wave propagated through the one workpiece due to the impact;
a storage device storing correlation data between the sample vibration intensity ratio and the throat thickness of the weld, which is obtained in advance using a plurality of test pieces having different throat thicknesses of the weld;
Substituting the ratio of the first vibration intensity measured by the first sensor and the second vibration intensity measured by the second sensor into the correlation data stored in the storage device and a calculator for calculating the throat thickness of the weld . 2. The weld zone inspection device according to claim 1, wherein the hit target member determination unit detects a step of the weld zone and determines a running direction of the weld zone inspection device. a first holder that supports the first sensor with the upper surface of the first sensor open ;
3. The weld inspection apparatus according to claim 1 , further comprising a second holder that supports the second sensor with an upper surface of the second sensor opened. . 4. The weld zone inspection apparatus according to claim 1, wherein the material to be welded on the far side and the material to be welded on the front side are fillet welded. 4. The weld inspection apparatus according to claim 3, further comprising a vertical movement mechanism for vertically moving the first holder and the second holder. a traveling device capable of traveling the material to be welded on the back side and the material to be welded on the front side;
a lateral direction moving mechanism provided in the traveling device for moving the first holder and the second holder in a width direction perpendicular to the traveling direction of the traveling device;
a control device provided in the traveling device for controlling the lateral movement mechanism and the traveling device;
6. The weld inspection apparatus according to claim 3, wherein the control device includes the arithmetic unit. a storage unit storing target position information;
a position sensor that detects the position of the traveling device,
The control device moves the traveling device to the target position based on the position of the traveling device detected by the position sensor and the target position information stored in the storage unit. 7. The weld inspection device according to 6. The running device
a wheel capable of traveling on the material to be welded on the back side and the material to be welded on the front side;
a housing supported by the wheels;
a battery that drives the wheels;
an independent suspension capable of independently adjusting the height of the wheels with respect to the housing,
6. The control device controls the independent suspension to maintain horizontality of the housing with respect to the material to be welded on the far side and the material to be welded on the front side. 8. The weld inspection device according to 7. a step detection sensor that detects a step between the material to be welded on the back side and the material to be welded on the front side to identify the position of the welded portion;
The control device controls the lateral movement mechanism so that the position of the weld specified by the step detection sensor is between the vibrating body and the first sensor that measures the first vibration intensity. The weld inspection apparatus according to any one of claims 6 to 8, wherein the first holder is moved in the width direction so that the first holder is positioned at . 10. The weld zone inspection apparatus according to claim 6, wherein the material to be welded on the far side and the material to be welded on the front side constitute a part of a bottom plate of an oil tank. The weld inspection apparatus according to any one of claims 6 to 10, wherein the travel device further includes a headlight and an obstacle detection device.

Images