JPH063341A - Self-traveling flaw detecting device - Google Patents

Abstract

PURPOSE:To enable a self-traveling flaw detecting device to perform highly accurate flaw detection when the device is actuated after the device is carried onto a plate to be inspected and moved to a starting position by providing ultrasonic transmitters-receivers which transmit and receive surface waves for measuring the distances to the edges of the plate to be measured. CONSTITUTION:Ultrasonic transmitters-receivers 16A and 16A' which are mounted on the front face of a self-traveling truck 12 and transmit and receive surface waves in the advancing direction of the truck 12 perform position measurement in the advancing direction and meandering control when the truck 12 advances in the direction shown by the arrow A. In addition, ultrasonic transmitters-receivers 14A and 14A' which are mounted on one side face of the truck 12 and transmit and receive surface waves in the direction perpendicular to the advancing direction of the truck 12 perform position measurement and meandering control in the direction perpendicular to the advancing direction of the truck 12 from the distance to the edge 10A of a plate 10 to be inspected. Since the meandering of the truck 12 is prevented by the actions of the transmitters-receivers 14a and 14A' and 16A and 16A' mounted on the truck 12 in the advancing direction and the direction perpendicular to the advancing direction two sets by two sets, the plate 10 can be inspected for flaw with high accuracy by means of a flaw detecting sensor 18A mounted on the front section of the truck 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-propelled flaw detector for nondestructively inspecting the surface quality and the internal quality of a metal plate made of a flat steel plate of a short or square shape, and in particular, an eddy current flaw detector,
Self-propelled flaw detection requiring magnetic flaw detection, ultrasonic flaw detection, etc. Regarding the device.

[0002]

2. Description of the Related Art An ultrasonic flaw detector is conventionally known as a device for nondestructively inspecting the surface quality and internal quality of a metal plate. Such ultrasonic flaw detectors include, for example, a fixed type as disclosed in JP-A-51-10882 and JP-A-59-133457, and one disclosed in JP-A-62-30952. Some are portable as disclosed.

[0003]

However, in the case of the fixed type ultrasonic flaw detector, it is necessary to carry a flat steel plate or the like to be inspected to the ultrasonic flaw detector, and in addition to the equipment of the ultrasonic flaw detector, The drive was subject to certain conditions. For this reason, there are severe restrictions on the thickness of the steel sheet that can be inspected.

On the other hand, in the case of a portable ultrasonic flaw detector, since a device guide and the like must be installed, it lacks versatility, and it takes time to detect flaws, and further, post-processing requires manpower. Was becoming.

Further, in the ultrasonic flaw detectors such as the above-mentioned conventional examples, when performing ultrasonic flaw detection on a wide range of steel plates without a track, it is possible to fix the probe as a flaw detection sensor to a hand or a trolley and perform the flaw detection manually. It was being appreciated. Therefore, it is difficult to obtain the linearity of the flaw detection inspection line and the accuracy of the probe position, and there is a problem that a manual operation requires a manual load.

On the other hand, although guide type unmanned flaw detectors and rail type unmanned flaw detectors are also known, in these cases, auxiliary equipment such as guides and rails must be prepared and installed, which requires manpower. Therefore, there is a problem that it is not practical.

Under these circumstances, the advent of a self-propelled flaw detector capable of achieving labor saving and high flaw detection accuracy has been strongly desired. Further, such a self-propelled flaw detector has also been required to be a portable device that can be carried to a required place at any time.

In view of the above situation, the present invention has been made to solve the above-mentioned problems of the conventional example. It is simply carried on a plate to be inspected, moved to a start position and activated. It is therefore an object of the present invention to provide a self-propelled flaw detection apparatus capable of performing flaw detection on the entire surface of the plate to be inspected or pitch detection with high accuracy.

[0009]

DISCLOSURE OF THE INVENTION The present invention is a flaw detector for moving and scanning a plate surface of a plate to be inspected by transmitting and receiving surface waves for measuring the distance to the edge of the plate to be inspected. The above problem is solved by providing a sound wave transmitter / receiver.

Further, according to the present invention, in a flaw detector for moving and scanning a plate surface of a plate to be inspected, a traveling device that moves forward or backward parallel to one side edge of the plate to be inspected, and the traveling of the traveling device. By providing a device for measuring a distance and an ultrasonic wave transmitter / receiver for transmitting and receiving a surface wave for measuring the distance in the left-right direction or the left-right front-back direction from the side edge of the plate to be inspected, the above-mentioned problems are solved. is there.

[0011]

In the present invention, the ultrasonic wave transmitter / receiver (hereinafter referred to as a surface wave sensor) for measuring the distance to the edge of the plate to be inspected, which is mounted on the self-propelled carriage, is used in the orthogonal 4 directions or the orthogonal 2 directions. The coordinate position of the traveling vehicle on the plate to be inspected is controlled by obtaining the distance from the plate edge in the direction. By such position control, it is possible to perform the straight-ahead control and the position control necessary for the full-face flaw detection or the pitch flaw detection for the self-propelled carriage equipped with the flaw detection sensor, the surface wave sensor, and the flaw detection device.

In this case, the higher the frequency of the surface wave transmitted from the surface wave sensor and the shorter the pulse length, the higher the distance resolution, but on the other hand, the unevenness of the plate surface of the plate to be inspected or stains such as adhered substances. The attenuation amount of the surface wave due to is also increased, and the arrival distance of the surface wave is shortened. Therefore, when the self-propelled flaw detector according to the present invention is used for flaw detection of a wide inspection plate or when it is necessary to improve the distance resolution, the plate surface of the inspection plate is smoothed and the plate surface is cleaned. It is desirable to carry out sufficiently.

The surface wave sensor is, for example, 4
One or a plurality of them are attached to one end face or two end faces orthogonal to each other, and the distance from each plate end of the plate to be inspected is measured.
In this case, surface wave sensors are attached to the four corners of the self-propelled carriage in the widthwise corners and the lengthwise both corners to prevent the meandering of the self-propelled carriage by compensating the mutual distances. The straightness accuracy of can be improved.

It should be noted that the distances from the four plate ends of the plate to be inspected are calculated as required, but normally, the distances from the two plate ends orthogonal to each other are calculated to control the position of the self-propelled carriage or to move straight. Take control. The position of the surface traveling wave sensor to be mounted on the self-propelled carriage can be arbitrarily selected according to the plate surface condition of the plate to be inspected, the state of the self-propelled carriage, etc., for example, one of the following first to third mounting methods. Is selected.

That is, the first mounting method is, as shown in FIG. 1, the X direction of the plate 10 to be inspected (the straight traveling direction of the self-propelled carriage 12).
Is detected by the traveling wheels of the self-propelled carriage 12, and the surface wave sensor travels so that one surface wave sensor 14 detects only one direction (downward in the figure) of the Y direction orthogonal to the X direction. This is a method of mounting on a dolly.

As shown in FIG. 2, the second mounting method is a method in which two surface wave sensors 14A and 14B are mounted in opposite directions on both ends of the traveling carriage in the Y direction orthogonal to the X direction. . This method is suitable when the plate 10 to be inspected has a large width and the end face echo of the surface wave is largely attenuated.

In the third mounting method, as shown in FIG. 3, for example, two surface wave sensors 16A and 16B are mounted not only in the Y direction but also in the X direction, and the position in the X direction also depends on the surface wave. A way to know. In this case, the surface wave sensor 1 in the Y direction
The number 4 may be one as shown in FIG. 1 or two as shown in FIG.

By the way, the self-propelled carriage is equipped with a flaw detection sensor necessary for flaw detection of the plate to be inspected. In order to perform flaw detection on the entire surface or pitch, for example, two flaw detection sensors are provided at both ends in the straight traveling direction of the traveling carriage. The two flaw detection sensors are mounted on the plate edge of the plate to be inspected at the same time, and cover the undetected area caused by the mechanical portion of the self-propelled carriage.

Further, in the width direction of the self-propelled carriage, a plurality of flaw detection sensors are mounted so as to have a width equal to or larger than the width of the carriage, or the flaw detection sensors are moved laterally in the vicinity of the lateral plate edge of the plate to be inspected. While performing flaw detection, it covers the undetected area.

When the self-propelled carriage reaches the plate edge in the straight direction, it is moved laterally by a required amount, for example, by laterally moving wheels, or by a scale insect mechanism for lifting the self-propelled carriage and moving it laterally. The self-propelled carriage can be moved laterally.

Further, it is also optional whether or not all the equipment and power source necessary for flaw detection are mounted on the self-propelled carriage. For example, the power source voltage, the detection signal and the like may be transmitted and received by wire through each cable. Alternatively, only the detection signal may be wirelessly transmitted and received.

The self-propelled flaw detector according to the present invention performs a predetermined whole-face flaw detection or pitch flaw detection unmanned and without orbit, and these flaw detection operations are completed by repeating the flaw detection conditions of the plate to be inspected.

[0023]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 4 is a distance measurement schematic diagram showing the principle of measuring the distance to the plate edge 10A of the plate 10 to be inspected by the surface wave sensor 14 according to this embodiment.
(A) is a vertical cross-sectional view, (b) is a plan view, and (c) shows ultrasonic signals transmitted and received by the surface wave generating and receiving ultrasonic wave transmitter / receiver constituting the surface wave sensor 14.

In FIG. 4, the surface wave emitted from the surface wave sensor 14 located on the inspection plate 10, that is, FIG.
The transmission echo T in (c) goes straight on the plate 10 to be inspected. When this surface wave reaches the plate edge 10A of the plate 10 to be inspected, a part of the surface wave detours in the direction perpendicular to the plate edge, but most of it returns to the direction orthogonal to the plate edge, that is, the direction straight ahead, and the surface wave again. The sensor 14 receives the end surface echo W. Therefore, if the surface wave sensor 14 is mounted so as to be orthogonal to the plate edge 10A of the plate 10 to be inspected, that is, the shortest distance, the distance x to the plate edge 10A of the plate 10 to be inspected is, for example, as shown in FIG. It can be obtained from the ultrasonic signals T and W in (c) according to the following equation (1).

X = (1/2) .T.C (1) where T: time (sec) C: sound velocity of surface wave (m / sec)

The frequency of ultrasonic waves is 0.5 to 5 MHz.
Is appropriate and is selected according to the surface condition of the plate 10 to be inspected and the measurement distance. In addition, the sound velocity C of the surface wave is
In case of steel, it is about 2950 (m 2 / sec).

FIG. 5 is a perspective view of the structure when a plate to be inspected is inspected by using this embodiment. In the figure, the same symbols as those in FIG. Is omitted. Further, 16A and 16A 'are mounted on the front surface side of the self-propelled carriage 12, ultrasonic transducers 14A and 14A' for transmitting and receiving surface waves in the straight traveling direction of the self-propelled carriage 12, and 14A and 14A 'on the side surface side of the self-propelled carriage 12. An ultrasonic wave transmitter / receiver 18A that is mounted and transmits / receives a surface wave in a direction orthogonal to the straight traveling direction of the carriage 12, 18A is a flaw detection sensor that is mounted on the front portion of the self-propelled carriage 12, and inspects the plate 10 to be inspected. The flaw detection equipment is a flaw detection recorder and a drive control panel.

A flaw detection sensor 18B (not shown in FIG. 5) identical to the flaw detection sensor 18A is also mounted on the rear portion of the self-propelled carriage 12, and these flaw detection sensors 18A, 1
8B scans the undetected area of the plate edge 10B in the traveling direction. In this case, first, the flaw detection sensors 18A and 18B
Scans the inspected plate 10 by the length of the self-propelled carriage 12,
After that, only the inspection sensor 18A in the traveling direction is used to inspect the plate 1
By scanning 0, an undetected area is prevented from being generated within the length of the self-propelled carriage 12 in the traveling direction. Usually, one or a plurality of these flaw detection sensors 18A and 18B are mounted on the traveling carriage 12, but when there is only one, that is, for example, only with the flaw detection sensor 18A, the direction of travel of the self-propelled carriage 12 is It is possible to move in the straight traveling direction at the plate ends 10A which are orthogonal to each other, so that no undetected flaw region remains at the end portion of the straight traveling direction.

In FIG. 5, the self-propelled carriage 12 travels straight in the direction A of the bold line arrow, and the surface wave sensors 16A and 16A 'measure the position in the straight travel direction and perform meandering control. Further, position measurement and meandering control in a direction orthogonal to the traveling direction of the self-propelled carriage 12 are performed from the distance to the edge 10A of the plate to be inspected 10 measured by the surface wave sensors 14A and 14A '. As described above, the surface acoustic wave sensors 14A and 14A mounted on the self-propelled carriage 12 two in each of the straight traveling direction and the orthogonal direction thereof.
The self-propelled carriage 12 is prevented from meandering by the operation of A, ', 16A, 16A'.

6 to 8 are explanatory views of the structure of this embodiment, FIG. 6 is a plan view, FIG. 7 is a side view, and FIG. 8 is a front view. Further, in FIGS. 6 to 8, the same symbols as those in FIGS. 4 and 5 are used with the same meanings, and the duplicated description is omitted here. Reference numerals 16B and 16B 'are attached to both ends of the rear portion of the self-propelled carriage 12, surface wave sensors for transmitting and receiving surface waves to the rear of the self-propelled carriage 12, and 14B and 14B' are attached to both side ends of the self-propelled carriage 12. , Surface acoustic wave sensors 22A, 22 for transmitting and receiving surface acoustic waves in a direction orthogonal to the straight traveling direction of the carriage 12.
B is a lateral movement mechanism that is mounted on the traveling carriage 12 and that includes wheels that move the carriage 12 in the width direction.

The lateral movement mechanisms 22A and 22B are mounted on the self-propelled carriage 12, and when the self-propelled carriage 12 reaches the plate edge 10B in the straight traveling direction, the self-propelled carriage 12 is lifted up to a necessary amount in a worm-like shape. Move it laterally. Note that such lateral movement may be performed only by the laterally moving wheels.

The surface wave sensors 14A, 14A ', 14B, 14B', 16 mounted on the four corners of the self-propelled carriage 12 are also provided.
Whether all A, 16A ', 16B, 16B' are activated depends on the required scanning accuracy.

When the grinder finish surface and a thick steel plate having a Ra of about 40 were inspected using the above-mentioned embodiment, when the frequency of the ultrasonic wave of the surface wave sensor was 2 MHz, the edges of the thick steel plate to be inspected were detected. A sufficient S / N ratio was obtained up to a distance of 5 m. Further, when the distance was measured using the end surface echo, the distance resolution was 8 mm. In order to compensate for this, it was possible to prevent the flaw leakage by setting an overlap of 10 mm with respect to the scanning width of the flaw detection in the XY directions.

[0035]

According to the present invention as described in detail above, in a non-destructive inspection for flaw detection of a plate to be inspected off-line, it is carried on the plate to be inspected, moved to a start position, and activated. A self-propelled flaw detection device capable of performing flawless and high-precision flaw detection on the plate to be inspected over the entire surface or pitch is realized.

Further, since the position control of the self-propelled carriage can be carried out by a relatively simple mechanism, there is an advantage that the handling is easy and the control accuracy is high.

Therefore, the man-hours required for assembling the device and the resolution, which are required in the above-mentioned conventional example, become unnecessary, and the plate surface of the plate to be inspected or Eddy current flaw detection, magnetic flaw detection, ultrasonic flaw detection, etc. in the plate can be performed unmanned and without orbit, and as a result, advantages such as labor saving can be achieved.

[Brief description of drawings]

FIG. 1 is a plan view showing an arrangement example of a surface acoustic wave sensor according to the present invention.

FIG. 2 is a plan view showing another example of arrangement.

FIG. 3 is a plan view showing still another arrangement example.

FIG. 4 is a distance measurement schematic diagram schematically showing the principle of measuring the distance to the plate edge of the plate to be inspected by a surface wave according to the present invention.

FIG. 5 is a perspective view of a configuration when a plate to be inspected is inspected by using the embodiment of the present invention.

FIG. 6 is a plan view showing the configuration of an embodiment of the present invention.

FIG. 7 is a side view of the same.

FIG. 8 is a front view of the same.

[Explanation of symbols]

10 ... Inspected plate 10A, 10B ... Plate edge 12 ... Self-propelled carriage 14, 14A, 14A ', 14B, 14B', 16A,
16A ', 16B, 16B' ... Ultrasonic wave transmitter / receiver (surface wave sensor) 18A, 18B ... Flaw detection sensor 20 ... Flaw detection equipment

Claims (2)

[Claims] 1. A flaw detection device for self-propelled scanning of a plate surface of a plate to be inspected, comprising an ultrasonic wave transceiver for transmitting and receiving a surface wave for measuring a distance to an edge of the plate to be inspected. A self-propelled flaw detector characterized by: 2. A flaw detection device for self-propagating and scanning a plate surface of a plate to be inspected, the traveling device moving forward or backward in parallel to one side edge of the plate to be inspected, and a traveling distance of the traveling device. A self-propelled flaw detector, comprising: a device for measuring a surface wave; and an ultrasonic wave transmitter / receiver for transmitting and receiving a surface wave for measuring a distance in a left-right direction or a left-right front-back direction from a side edge of a plate to be inspected. .