JPH05816Y2 - - Google Patents

Description

[Detailed Description of the Invention] A. Field of Industrial Application The present invention relates to an X-ray fluoroscopic corrosion inspection device for inspecting the distribution of the degree of corrosion on the surface of a steel plate or the like.

B. Prior Art Conventionally, to inspect the degree of corrosion on a surface such as a steel plate surface, a thickness gauge using X-rays or a commonly used surface roughness tester has been used.

However, although this type of thickness gauge can measure the thickness of a local area, it cannot measure the thickness of a large area at once. Therefore, it is extremely inconvenient to investigate the distribution of the degree of corrosion over the entire surface of the steel material.

In addition, the thickness gauge using X-rays simply converts the X-rays transmitted through the steel plate into a luminance distribution via an image intensifier in relation to the thickness of the steel plate surface. For example, for a 1 mm steel plate, the detection of thickness changes of about 0.02 to 0.03 mm is the limit, and even an experienced person could not detect a slight change in thickness clearly enough. However, it has the disadvantage that it cannot be used, for example, to inspect the surface of a steel plate in the quality control process of products using steel plates.

C. Purpose The present invention provides an X-ray fluoroscopic corrosion inspection device that can easily inspect the distribution of the degree of corrosion on the surface of a steel plate over a wide area without the need for specially trained inspectors. It is intended to.

D. Configuration The X-ray fluoroscopic corrosion inspection device according to the present invention uses a video signal obtained by transmitting X-rays through a sample, and a plurality of threshold levels preset according to the degree of corrosion. By comparing the values, the video signal is converted into a color pulse corresponding to the threshold level, and based on this, the distribution of the corrosion degree of the sample is displayed on a color CRT screen.

E. Embodiment FIG. 1 is a block diagram of an X-ray fluoroscopic corrosion inspection apparatus according to the present invention.

In the figure, 1 is an X-ray tube that irradiates X-rays onto the surface of a sample 22, such as a steel plate, by a high-voltage generator 11 controlled by a controller 12;
- Y table, installed in front of X-ray tube 1,
A sample 22 is placed on top of the sample. Reference numeral 3 denotes an X-ray image intensifier, which is installed in front of the X-Y table 2 and converts an X-ray image obtained by passing through a sample into a visible light image consisting of a luminance signal.

A television camera 4 is installed on the image output side of the X-ray image intensifier 3, and captures an image of visible light output from the X-ray image intensifier 3, converting it into a video signal consisting only of luminance signals. Convert to

A monitor television 5 is connected to the output end of the television camera 4 and displays the waveform of the video signal.

Reference numeral 6 denotes a frame memory, which is connected to the image signal output terminal of the monitor television 5. This frame memory was connected because X-ray video signals are very noisy, and if only one frame of video signal is used, the image will flicker, so a memory is provided for each pixel on the image plane. For example, it is configured to store video signals for 10 frames and output the integrated value as the video signal.

Furthermore, 7 is a conversion unit connected to the frame memory 6, which compares the monochrome video signal with, for example, seven threshold levels set in advance corresponding to the degree of corrosion. This is for converting the video signal into color pulses corresponding to each threshold level. It is also a part that adds a signal to the video signal for displaying the area ratio of the color level and other necessary information on the color CRT screen.

Reference numeral 8 denotes a color monitor, which is connected to the conversion section 7 and displays the degree of corrosion on the surface of the sample 2 and necessary related information as a color screen on a color CRT screen.

FIG. 2 is a block diagram of the conversion section 7.

711 is a video signal input terminal to which a video signal from the frame memory 6 is input.

721 is a synchronization signal separation and amplification circuit that separates and amplifies horizontal and vertical synchronization signals from the video signal, and is connected to the video signal input terminal 711.

722 is a horizontal and vertical driver connected to the synchronization signal separation and amplification circuit.

731 is a masking section, and the video signal input terminal 7
11, and allows only video signals related to pixels in a predetermined area to pass through in order to output only the necessary portions of the sample on a color CRT screen.

A comparison circuit 741 is connected to the output terminal of the masking section 731, and a setting device 751 is connected to the comparison circuit 741.

732 is an A/D converter, and a comparison circuit 741
Based on the output of the input video signal, the input video signal is converted into a 3-bit color pulse corresponding to the threshold level.

733 is an attenuator that changes the "H" voltage of the color pulse from 5V to 0.7V in order to convert the output of the A/D converter 732 to a level suitable for color CRT.
attenuates to

742 is the character display section, A/D
It is connected to the output end of the converter 732, and converts various data such as sample name and measurement conditions inputted from the key input section 752 into character signals for output on a color CRT screen.

A counter 743 is connected to the output terminal of the A/D converter 732. This counter 743 counts the color pulses for each color, calculates and outputs the ratio to the total number of pulses, that is, the ratio of each color in the sample image on the CRT screen.

744 is a counting display section, and the counter 7
Connected to the output terminal of 43 and colorizes the calculation results.
Performs signal conversion for output on CRT screen.

734 is a mixer, which includes an attenuator 733, a character display section 742, and a counting display section 74.
4, in order to output the signals from each section to a predetermined location on the color CRT screen.
Combine into a predetermined pulse signal.

A driver 735 is connected to the output end of the mixer 734 and converts the pulse signal into a video signal.

A video signal output terminal 713 is connected to the output terminal of the mixer 734 and outputs the video signal to each of the R, G, and B terminals of the color monitor 8.

FIG. 3 is an explanatory diagram for explaining the operating principle of the comparison circuit 741.

In the figure, it is assumed that S is a video signal input to the comparison circuit 741. Further, L1 to L7 are threshold levels, which are arbitrarily set in advance by the setting device 751. As shown in the figure, between each threshold level, black is below L1, blue is between L1 and L2, red is between L2 and L3, purple is between L3 and L4, and green is between L4 and L5.
Blue-green is assigned to L5-L6, yellow is assigned to L6-L7, and white is assigned to L7 and above.

Next, the operation of this embodiment will be explained.

An X-ray image obtained by irradiating a desired portion of the test sample 22 on the X-Y table 2 with X-rays using the X-ray tube 1 is converted into an image using visible light by the X-ray image intensifier 3. be done. The image is converted into a monochrome video signal by the television camera 4.

The waveform of the video signal is monitored by a monitor television 5 and is also applied to a frame memory 6, where image flickering is removed by the signal integration effect described above.

Next, the video signal is input to the video signal input terminal 711 of the converter 7.

The video signal input to the video signal input terminal 711 is provided to a synchronizing signal separation and amplification circuit 721 and a masking section 731.

From the video signal given to the synchronization signal separation and amplification circuit 721, only the synchronization signal is extracted, and the driver 7
22 generates synchronization signals necessary for the color CRT.

Further, among the video signals given to the masking section 731, only the video signals related to pixels in a predetermined area pass through this. The video signal output from the masking section 731 is sent to an A/D converter 732 and a comparison circuit 74.
1 is given.

The video signal applied to the comparison circuit 741 is compared with the threshold level described above, and when the value of the input video signal is between any of the threshold levels, a comparison output corresponding to each level is generated. Output.

The comparison output is then input to an A/D converter 732. As a result, the A/D converter 73
2 converts the video signal into a color pulse composed of 3 bits and outputs it.

The color pulse input to the attenuator 733 has its "H" voltage attenuated from 5V to 0.7V. The character display section 742 converts other data inputted from the key input section 752 into character signals in order to display various data such as the sample name and measurement conditions on the color CRT screen.

Further, the counter 743 counts the color pulses for each color, calculates the ratio to the total number of pulses, and outputs the result. Counting display section 74
In step 4, signal conversion is performed in order to display the calculation results.

The signals output from the attenuator 733, the counting display section 744, and the character display section 742 are combined into a predetermined pulse signal by a mixer 734.

The pulse signal is converted into a predetermined video signal by the driver 735, and the video signal output terminal 71
Output from 3.

In this way, an image displaying the distribution of the degree of corrosion of the sample in color is displayed on the color monitor 8.

FIG. 4 is an example of an image displayed on the color CRT screen of the color monitor 8.

In the same figure, 81 is an X-ray fluoroscopic image displayed in color, with black, blue, red, purple, green, and
Colored in blue-green, yellow, and white.

Reference numeral 82 indicates the area ratio occupied by each color in the image of the sample, which is displayed as a percentage below each color of the color code 83.

Reference numeral 84 is a character display on which the various data described above are displayed.

F. Effect The X-ray fluoroscopic corrosion inspection device according to the present invention performs X-ray fluoroscopy on a sample whose thickness differs in each part depending on the degree of corrosion progress, and uses the video signal obtained from this X-ray image and the corrosion A device that compares the video signal with a plurality of predetermined threshold levels corresponding to the thickness of the sample (sample thickness), converts the video signal into a color pulse corresponding to the threshold level, and provides this to a color monitor. Therefore, the distribution of the degree of corrosion progress of the sample can be displayed in color.

Therefore, according to this invention, the distribution of the degree of corrosion on the sample surface can be inspected very accurately and easily. In other words, it has been confirmed through experiments that the device of the present invention can detect changes in thickness of up to 0.01 mm in a 1 mm thick steel plate.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the X-ray fluoroscopic corrosion inspection apparatus according to the present invention, and FIG. 2 is a block diagram of the converting section 7.
FIG. 3 is an explanatory diagram for explaining the operating principle of the comparator circuit 741, and FIG. 4 is a diagram showing the color of the color monitor 8.
This is an example of video display on a CRT screen. 1...X-ray tube, 2...X-Y table, 3...
Image intensifier, 4... TV camera, 6... Frame memory, 7... Conversion unit, 8...
...Color monitor.

Claims (1)

[Scope of utility model registration request] An X-ray tube that irradiates the surface of a sample such as a steel plate with X-rays, an X-Y table on which the sample is placed, an X-ray image intensifier and a television camera that amplify the image of the X-rays that pass through the sample. means, a monitor television that receives the output of the television camera and monitors the waveform of the video signal, a frame memory that stores a plurality of frames and outputs an integral value thereof, a converter connected to the frame memory, and a plurality of converters. An X-ray fluoroscopic corrosion monitor equipped with a color monitor in which a threshold level is set in advance and a video signal is converted into color pulses corresponding to the threshold level to display the corrosion degree distribution of the sample in color. In the inspection device, the conversion unit includes at least a masking unit that receives the output of the frame memory and passes only video signals related to pixels in a predetermined area, and a comparison circuit that compares the output of the masking unit and the output of the setter. There is an A/D converter that converts the output of the comparison circuit into A/D, a character display section that converts various data such as the sample name and measurement conditions entered through the key input section into character signals, and a color pulse that counts color pulses for each color. An X-ray fluoroscopic corrosion inspection device characterized by having a counter that calculates and outputs a ratio to the total number of pulses.