JP2001330592A - Steel edge automatic flaw detector - Google Patents

Abstract

(57) [Problem] To provide a steel material end automatic flaw detection device capable of performing high-speed and reliable automatic flaw detection by leakage magnetic flaw detection on an end surface. SOLUTION: After one rotation of the test material or the sensor, the test material or the sensor is moved in the axial direction of the test material by a width that can be detected by the sensor, and then rotated once again to guarantee the flaw of the entire length. An automatic flaw detection device for steel ends, which is made possible. In addition, two rows of sensors are arranged side by side, which are shifted by the detectable width of the sensor, and the inspection material or the sensor is rotated once to guarantee the entire length of the flaw. Automatic steel flaw detector. In addition, using a sensor that faces the sensor shifted by the width that can be detected by the sensor, and by making one rotation of the test material or the sensor, it is possible to guarantee the flaw of the entire length of the steel material. Flaw detector.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic flaw detector for steel ends.

[0002]

2. Description of the Related Art Conventionally, flaw detection other than the end portion of a steel material is performed by magnetic flux leakage detection and eddy current detection. Automatic flaw detection is performed by ultrasonic flaw detection or the like, but a pseudo signal is generated at the end of any flaw detection method. If there is a flaw in the area (edge) where the pseudo signal is generated, the amplitude of the fake signal chart is large. It is difficult to identify flaws. On the other hand, if the pseudo signal is generated, the pseudo signal is determined as a flaw, so that automatic flaw detection is not performed. This is what is called an end dead zone. In order to guarantee this end dead zone, a visual inspection or a manual magnetic inspection is generally applied as a flaw detection of the end surface. In the case of the visual inspection and the manual inspection, there are problems that productivity is impaired and that there is a high possibility of oversight.

[0003]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present inventors have made intensive developments. As a result, high-speed and reliable flaw detection at the end and full-length flaw detection at the lowest possible cost are possible. An object of the present invention is to provide an automatic flaw detection device for an end portion of a steel material, which enables the inspection.

[0004]

The gist of the invention is as follows. (1) After the test material or the sensor makes one rotation, the test material or the sensor can be flaw-detected in the axial direction of the test material. An automatic flaw detection device for a steel material end, wherein a flaw of the entire length can be assured by moving by a width and making another rotation. (2) Using two rows of sensors, which are arranged side by side with sensors shifted by the width that can be detected by the sensors, making it possible to guarantee the entire length of the flaw by rotating the test material or sensor once. Automatic flaw detection equipment. (3) The end of a steel material characterized by using a sensor facing the sensor shifted by the detectable width of the sensor and making a full rotation of the inspection material or the sensor by rotating the sensor one time. In automatic flaw detection equipment.

Hereinafter, the present invention will be described in detail with reference to the drawings. First, a two-rotation type steel end automatic flaw detector will be described. As described above, except for the end portion, automatic flaw detection is performed by leakage magnetic flux inspection, eddy current inspection, ultrasonic inspection, and the like.However, it is extremely difficult to reduce the dead zone at the end as much as possible. An automatic flaw detection device dedicated to flaw detection was introduced to make the configuration line as shown in FIG. That is, the steel material unbundled from the unwinding table 1 is subjected to flaw detection in the flaw detection device 2 other than the end portion, and subsequently, in the end flaw detection device 3, the front and rear end flaw detection of the steel material is performed to detect flaws and determine the quality. It is transferred to the binding unit 5.

[0006] In the end flaw detection device 3 in such a configuration line, as described above, when the test material is sent in the longitudinal direction, a pseudo signal of the end is generated. Therefore, the test material is not sent in the longitudinal direction. In addition, only the rotation of the end flaw detection transfer table 4 is performed. On the other hand, the method of moving the sensor by the detectable width of the sensor in the second rotation includes a method of moving the sensor and a method of moving the material. When moving the material, the moving distance is moved with the accuracy required for this method. It is a sensor-moving type because it is difficult to do so and the moving mechanism becomes large.

There are two types of rotary type: a rotary type of material and a rotary type of probe (sensor). In the case of the rotary type of material, it is only necessary to rotate with a contact roller. Are required, and the mechanism is more complicated in the case of the probe rotating type. further,
As described above, since the sensor is of the moving type, in the case of the probe rotating type, it is moved while rotating, so that the structure is further complicated. For these reasons, the material rotation type was used in consideration of the space and cost of equipment installation.

FIG. 2 is an explanatory view showing a state in which the test material is rotated in the end flaw detection according to the present invention. FIG. 2A shows a state where the test material is rotated once. The sensor has an effective width that can be detected, and as shown in this figure,
Even if the sensor 7 is arranged in the flaw detection device 3 with respect to the test material 6, a flaw detection portion 8 and a non-flaw detection portion 9 are generated. FIG. 2B shows the state of the test material in the second rotation. This figure 2
As shown in (b), the flaw detection part 8 and the non-flaw detection part 9 of the test material 6 after sliding the flaw detection device 3 in the direction of the arrow are shown. As a result, the undetected portion in FIG. 2A is detected.

FIG. 3 is a diagram showing the structure of the sensor.
As shown in FIG. 3, as a method for solving the above-mentioned occurrence of the flaw detection portion and the undetected portion, as shown in FIG. 3A, a very large sensor 7 having the same size as the flaw detection device 3 is used. Either one is provided, or conversely, as shown in FIG. 3B, many small sensors are arranged. However, the former is not feasible because the flaw detection capability is reduced because the flaw detection capability is reduced when the sensor is large. On the other hand, the latter increases the flaw detection capability due to the smaller sensor, but increases the cost due to the increased number of sensors. Further, since the effective portions of the sensors are close to each other and interfere with each other, flaw detection is difficult and difficult to realize.

From the above, the present invention will be described with reference to FIG. FIG. 4 is a diagram showing a two-rotation type flaw detection according to the present invention. As shown in FIG. 4, the first rotation of the test material 6 is performed. When the flaw detection device 3 is slid in the axial direction of the test material 6 at the stage where the flaw detection in the first rotation is completed, a flaw-detected portion and an unflaw-detected portion are generated in a portion different from the first rotation in the second rotation. In consideration of this, the size of the sensor is selected so that the flaw-detected portion and the unflaw-detected portion are equalized, and the slide amount is set to the effective width of the sensor, so that the entire surface of the end portion can be flaw-detected.
In combination with the automatic flaw detection other than the end, the flaw of the entire length can be guaranteed by the automatic flaw detection device.

Next, the one-rotation type will be described. FIG.
FIG. 2 is a view showing a one-turn type flaw detection according to the present invention. As shown in this figure, two sensors which are displaced by the detectable width of a flaw detection device I of a certain sensor 7 and a flaw detection device II of the sensor 7 are provided, and since these two sensor rows are provided, the sensors are provided. Since a mechanism for moving the material is not required, the space for installing the equipment and the cost are excellent.
By arranging such two sensors, the flaw detection shown in FIG. 2 or FIG. 3 is simultaneously performed at the stage of one rotation, and the entire surface of the end can be guaranteed by one rotation. FIG. 6 is a diagram showing another one-turn type flaw detection according to the present invention. As shown in this figure, by using a sensor in which the sensor shifted by the detectable width of the sensor is opposed to each other, and by rotating the test material or the sensor once, the entire length of the flaw is guaranteed as in FIG. It is something that can be made possible.

[0012]

The present invention will be specifically described below with reference to examples. In the embodiment of the present invention, a two-turn type flaw detector is employed. That is, the number of rotations of the probe is 400 to 600r.
pm, the material feeding speed is 80 to 100 m / s, and the two-rotation type magnetic flux leakage flaw detection device has a dead zone of about 150 mm at the end and allows flaws with a depth of 0.2 mm to be detected. The flaw detection width is 6.5 as a flaw detection device dedicated to the part
Sixteen mm sensors were arranged, and the end 208 mm was exclusively flaw-detected. In addition, the flaw detection apparatus is a leakage magnetic flux method in consideration of the flaw detection on the end surface and the condition of the surface skin of the test material. Theoretically, flaw detection can be performed on the entire end portion by two rotations. However, in consideration of some margin, the flaw detection device slides at 1.25 rotations, and is completed at 2.5 rotations. As a result of performing sensitivity calibration on the flaws of the comparative test piece and evaluating by the deflection width of the chart, the flaw signal at the end can be inspected clearly without any false signal.

[0013]

As described above, according to the present invention, it is possible to perform high-speed and reliable automatic flaw detection at the end surface by leakage magnetic flaw detection without any oversight of flaws as in the case of the visual inspection as in the prior art. This is extremely advantageous industrially.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration line of the present invention;

FIG. 2 is an explanatory view showing a state where a test material is rotated in the end flaw detection according to the present invention;

FIG. 3 is a diagram showing a structure of a sensor.

FIG. 4 is a view showing a two-rotation type flaw detection according to the present invention;

FIG. 5 is a diagram showing one-turn type flaw detection according to the present invention;

FIG. 6 is a view showing another one-turn type flaw detection according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Unwinding table 2 Flaw detector other than the end 3 End flaw detector 4 End flaw transfer table 5 Binding table 6 Material to be inspected 7 Sensor 8 Flaw detector 9 Non-flaw detector

Claims (3)

[Claims] After the test material or the sensor makes one rotation, the test material or the sensor is moved in the axial direction of the test material by the width that can be detected by the sensor, and the test material or the sensor is rotated once again to guarantee the flaw of the entire length. An automatic flaw detection device for steel ends, characterized in that: 2. The use of two rows of sensors in which sensors displaced by the width that can be detected by the sensors are arranged side by side, and the inspection material or the sensor is rotated once to make it possible to guarantee the entire length of the flaw. A special feature for automatic detection of steel edges. 3. A steel material characterized by using a sensor facing a sensor displaced by a width that can be detected by the sensor and making a full rotation of the test material or the sensor by making one revolution of the sensor. Edge automatic flaw detector.