KR100550289B1 - Light source mechanism for DWTT test between ductility and brittleness - Google Patents

Abstract

The present invention relates to a lighting device for detecting a ductile and brittle fracture surface,

In the illumination device for detecting the ductile and brittle fracture surface of the DWTT specimen (1) fixed to the specimen holder (6), the A-channel illumination (2) installed on the upper support vertically installed at both ends of the specimen holder (6) And B channel illumination 3; A CCD camera (4) installed on the specimen (1) to photograph the fracture surface of the specimen (1); A rotation driving unit 16 installed on the support to rotate the respective lights 2 and 3; A linear driving unit (17) installed on the support for linearly moving the respective lights (2, 3) up and down; A laser sensor 5 installed to move up and down along a guide surface installed between the specimen 1 and the support to detect a fracture surface of the specimen 1; A linear driving unit 18 installed on the guide surface to linearly move the laser sensor 5 up and down; It characterized in that it comprises a control unit for controlling the adjustment of the irradiation angle and the vertical position of the A, B channel illumination (2, 3) and the vertical position of the laser sensor (5),

It provides a lighting device that can obtain better image results than the automated DWTT test and evaluation system of the image processing method, and solves the problems caused by the error of the lighting angle and illumination setting process to make the test method more reliable. In particular, since it has the advantage of minimizing the test error caused in a variety of testing process, it provides an effect that can be used for the general purpose of the developed device.

DWTT test, light source, laser sensor, lighting equipment

Description

Light source mechanism for DWTT test between ductility and brittleness}

1 is a configuration diagram schematically showing the configuration of the lighting device for detecting DWTT ductile and brittle fracture surface according to an embodiment of the present invention.

Figure 2 is a flow chart showing the operation of the lighting device for detecting DWTT ductile and brittle fracture surface according to an embodiment of the present invention.

Figure 3 is a perspective view schematically showing a lighting device for detecting DWTT ductile and brittle fracture surface according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

1: DWTT Specimen 2: A channel lighting

3: B channel lighting 4: CCD camera

5: laser sensor 6: specimen holder

7: vision process unit 8: light control unit

9: light source irradiation angle servo controller 10: light source shanghai song servo controller

11: laser sensor Shanghai Song servo controller

12: laser measuring unit and driver

13: A / D input / output unit 14: Transfer device control unit

15: control computer 16: rotary drive unit

17: linear drive unit 18: linear drive unit

19: illuminometer 20: angle of illumination

The present invention relates to a lighting device for detecting DWTT ductility and brittle fracture surface, and more specifically to automatically inspect the fracture surface of the specimen for the DWTT (Drop Weight Tear Test) test used for the quality test of the steel sheet produced by the hot rolling process In order to maximize the effect of the image processing device, the DWTT which automatically obtains the best image acquisition and separation for the specimens put into the test by automatically changing the illumination angle of the lighting device in consideration of the shape and height of the fracture surface. The present invention relates to a lighting device for detecting a ductile and brittle fracture surface.

Recently, the use of pipelines for transferring crude oil, natural gas, etc. is increasing, and steel materials used at this time have very high quality control standards compared to existing steels.

The steel used for this purpose is the American Petroleum Institute steel (API steel), which is attracting attention as a future core field of the steel industry.

In the case of commonly used steels, breakdowns due to continuity defects in the inclusion and composition contained in the steel are frequently generated, which causes serious problems such as pipe leakage in the transport pipeline. In fact, the transport of gas and crude oil is carried out using high pressure, so the generation of minute pinholes or cracks can cause large accidents and environmental pollution.

The above-mentioned high clean steel deals mainly with two characteristics of ductile fracture and brittle fracture. The DWTT test mentioned above is used as a basic data to determine how resistant the steel products manufactured by identifying the ductile fracture and brittle fracture phenomena to external impact factors. Will be displayed.

The basic method of the DWTT test is from fracture or flat to brittle fracture (Shear or Oblique) for carbon or low alloy steel pipes of YP84.4kgf / mm2 (12000㎰i) or less. It is intended to measure the fracture propagation shape at temperatures exceeding the varying temperature range and should be capable of breaking the specimen completely at one time by impact during the test. At this time, the speed of the impact hammer for breaking should be at least 4.88 m / s based on ASTM (E436).

API high-clean steels have a speed within 5-9 m / s. In addition, the notch processing, which is the starting point of the breaking process used to achieve the breaking effect, should be located within 1.59 mm from the center line of the hammer, and the test height is set to about 1000 Joules per 1 mm of specimen thickness.

In the case of the DWTT test, the fracture surface is generated by the impact, and the fracture surface that appears at this time has a broken shape in the case of ductile fracture, so that the fracture surface increases and breaks like a mountain, and in the case of brittle fracture, such tensile Since it shows a broken shape without a process, it creates a flat and uniform fracture surface, not an elongated mountain fracture surface.

The results of the above-described DWTT test and inspection process are divided into manual inspection technique by an operator and an automated apparatus using an image processing apparatus using a CCD camera. Among them, a method of securing quantification and reliability is used as an automatic apparatus using an image processing technique. If the ductile fracture surface and brittle fracture surface are separated correctly, more accurate results can be obtained.

Such an image separation device uses a diagonal light, and the imaging condition may vary greatly depending on the result of the adjustment of the angle of the diagonal light used, which directly affects the inspection result. That is, in order to obtain more improved image processing results, optimization of illuminance and illumination angle of the diagonal illumination light source is required, but there is a problem in that there is no appropriate lighting device.

Therefore, there was a problem that an error occurs in the setting process by manually setting the illumination angle and illuminance.

The present invention has been made to solve the above-mentioned conventional problems, the object of the present invention is to add a driving mechanism to the laser sensor (laser sensor) and the illumination for determining the shape of the fracture surface of the specimen specimen of the fracture surface It is to provide a DWTT ductile and brittle fracture detection device capable of automatically adjusting the illumination angle according to the shape and automatic adjustment of illuminance.

The present invention for achieving the above object, in the illumination device for detecting the ductile and brittle fracture surface of the DWTT specimen (1) fixed to the specimen holder (6), perpendicular to both ends of the specimen holder (6) A channel light (2) and B channel light (3) installed on the upper support is installed; A CCD camera (4) installed on the specimen (1) to photograph the fracture surface of the specimen (1); A rotation driving unit 16 installed on the support to rotate the respective lights 2 and 3; A linear driving unit (17) installed on the support for linearly moving the respective lights (2, 3) up and down; A laser sensor 5 installed to move up and down along a guide surface installed between the specimen 1 and the support to detect a fracture surface of the specimen 1; A linear driving unit 18 installed on the guide surface to linearly move the laser sensor 5 up and down; And a control unit for controlling adjustment of the irradiation angles and the vertical position of the A and B channel lights 2 and 3 and the vertical position of the laser sensor 5.

More preferably, it further comprises an illuminometer 19 installed on the side of the CCD camera 4 to measure the illuminance of the reflected light, wherein the control unit according to the measurement results of the illuminometer 19, the A, B channel The illuminance of the lights 2 and 3 is controlled.

More preferably, the control unit includes a light control unit (8) for controlling the illuminance of the A, B channel illumination (2, 3); A light source irradiation angle servo controller (9) for controlling the rotation driving unit (16) for adjusting the irradiation angles of the A and B channel illuminations (2, 3); A light source shanghai servo controller (10) for controlling the linear driving unit (17) for moving the positions of the A and B channel lights (2, 3); A laser sensor shanghai song servo controller (11) for controlling the linear driving unit (18) for moving the position of the laser sensor (5); A laser measuring unit and driver 12 for controlling the detection of the laser sensor 5; A transfer device control unit 14 for transmitting control signals to the servo controllers 9, 10, 11 is provided.

More preferably, the A, B channel illuminations 2, 3 have an illumination angle 20 adjusted in the range of substantially 30 to 40 ° with respect to the center of the peak of the specimen 1.

More preferably, the rotary drive unit 16 is a stamping motor.

More preferably, the linear driving units 17 and 18 are linear motors.

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

1 is a schematic view showing the configuration of a lighting apparatus for detecting a DWTT ductile and brittle fracture surface according to an embodiment of the present invention, Figure 2 is a DWTT ductile and brittle fracture detection surface according to an embodiment of the present invention 3 is a flow chart showing the operation of the lighting device, Figure 3 is a perspective view schematically showing a lighting device for detecting DWTT ductile and brittle fracture surface according to an embodiment of the present invention.

As shown in Fig. 1 and Fig. 3, in the lighting apparatus according to the present embodiment, the specimen 1 is fixed to the specimen holder 6 on the bottom surface. For example, it is preferable that the specimen holder 6 is fixed by using a magnet or clamping means so that the specimen 1 does not move during imaging. The CCD camera 4 for photographing the fracture surface image of the specimen 1 is provided in the upper surface of the central part of the specimen 1. An illuminometer 19 for measuring illuminance of reflected light is provided on the side of the CCD camera 4.

 A channel light 2 and B channel light 3 are installed on both support upper portions perpendicular to both ends of both sides while being inclined with the center of the specimen 1. The A and B channel lights 2 and 3 are provided with a rotary drive part 16 for adjusting the irradiation angle and a linear drive part 17 for conveying the A and B channel lights 2 and 3 up and down on the support. It is. For example, it is preferable that the rotation driving unit 16 uses a stepping motor capable of rotating by a predetermined angle, and the linear driving unit 17 uses a linear motor. Accordingly, the A and B channel lights 2 and 3 can change the irradiation angle and the irradiation position.

In addition, between the specimen 1 and the A-channel illumination 2, a laser sensor 5 for detecting the position of the specimen 1 is provided on the feed shaft, and is conveyed up and down by the linear drive 18 along the feed shaft. do. The linear drive unit 18 preferably uses a linear motor.

The control unit of the lighting apparatus includes a vision process unit 7, an optical control unit 8, a light source irradiation angle servo controller 9, a light source shanghai servo controller 10, a laser sensor shanghai servo controller 11, and a laser measuring unit. And a driver 12, an A / D (Analog / Digital) input / output unit 13, a transfer device control unit 14, and a control computer 15.

The vision process unit 7 converts an image signal received from the CCD camera 4 into a signal that can be recognized by a computer.

The light control unit 8 performs illuminance control of the A channel illumination 2 and the B channel illumination 3 according to the result of measuring the illuminance of the reflected light in the illuminometer 19 and controls the power supply.

The light source irradiation angle servo controller 9 controls the rotation driving unit 16 to adjust the irradiation angles 20 of the A and B channel lights 2 and 3. The light source shanghai servo controller 10 controls the linear driving unit 17 to be vertically conveyed in order to adjust the irradiation positions of the respective A and B channel lights 2 and 3.

The laser sensor Shanghai feed servo controller 11 controls the linear drive unit 18 for vertically conveying the laser sensor 5 to detect the position of the specimen 1.

The laser measuring unit and driver 12 includes an oscillation part for driving the laser, a driving driver, and the like for controlling the laser measurement of the laser sensor 5 to detect the position of the specimen 1.

The A / D input / output unit 13 is a board that connects the external input / output of the control computer 15, a synchronization signal, a control signal of each transfer device, an illumination control signal, a defect control signal, and the vision process unit ( It serves to interface external I / O such as video signal by 7).

The conveying device control unit 14 controls the irradiation angle of each of the A and B channel lights 2 and 3, the shanghai song of each of the A and B channel lights 2 and 3, and the shank of the laser sensor 5. It controls the servo controllers 9, 10 and 11, and serves to supply power to each drive unit.

The control computer 24 is provided with image processing software as a basic system of the lighting processing apparatus. The control computer 24 controls the software and collectively controls the entire system such as the control of the A / D input / output unit 23. At this time, general PC and industrial PC can be selectively used according to the working environment and operating conditions, and it is desirable to use an appropriate control computer because it may affect the processing speed depending on the performance of the system.

Generally, ductility and brittle fracture are mixed in case of specimens obtained from DWTT test equipment, but the height and shape of fracture surface appear very different due to these causes.

In the case of ductile dominance, the height of the mountain part indicated by the oblique line is increased, which is a result of the ductility being strong during the destruction process, and the degree of swelling is large. As a result, the height of the fracture surface is increased.

On the other hand, if brittle fracture appears predominantly, brittleness prevails in the process of destruction, so the height of the mountain part is lowered because brittle fracture does not increase much and brittle fracture occurs. As a result, the height of fracture surface is lowered. .

As described above, the fracture surface varies depending on the ratio of ductility and brittle fracture. In order to obtain the best image for the various shapes, the angle and illuminance of the illumination irradiated to the fracture surface must be adjusted.

As shown in FIG. 1, when the specimen 1 of which the DWTT test is completed is fixed in position and the apparatus is operated, the laser sensor 5 located on the side of the specimen 1 moves from the bottom to the top. In this process, when the laser sensor 5 detects the fracture surface of the specimen which is essentially generated in the DWTT test process, a notch inwardly generated due to the characteristics of the fracture surface is generated, and thus, the distance between the laser sensor 5 and the specimen. It recognizes the change and judges it as a notch, and scans from here as a starting point for the point where the change in distance of the shape of the notch of the specimen is recognized.

The laser sensor 5 is continuously raised from the notch in the same manner as described above, and the distance scanned is calculated to determine where the highest point of the tension surface generated on the specimen 1 is obtained. In this process, the shape of the fracture surface is measured by measuring the distance from the notch portion of the specimen 1 to the highest point, and the illumination angle 20 is changed based on the result. The illumination angle 20 used in the DWTT automatic tester is preferably in the range of 30 to 40 ° based on the center of the highest point of the specimen (1). If the illumination angle 20 is smaller than 30 °, the bright part of the fracture surface of the test piece 1 increases, making it difficult to distinguish between the soft surface and the brittle surface as in general lighting, and an error occurs, and the illumination angle 20 is 40 If it is larger than °, when the fracture surface of the specimen 1 is in the shape of a mountain, the dark portion is increased so that the error increases sharply, so that image analysis is not properly performed.

Therefore, the calculation process is made so that the irradiation angle of 30 ~ 40 ° based on the highest point of the measured specimen (1) to drive the servo device for moving and moving the angle of the lighting device to achieve the optimum irradiation angle.

In this process, the illuminance of the reflected light is measured using an illuminometer 19 installed in the lighting apparatus, and the illuminance of the diagonal illumination light source is set by comparing the illuminance of the reflected light appearing at this time with a set value. Up to this process, the lighting devices of A and B channels are turned on at the same time to complete the setting of the lighting devices, and then the standby process is performed for the video measurement process through independent driving of A and B channels. It is fixed without any change of lighting device.

Once one test procedure is completed and the next specimen is loaded, the above procedure is repeated to set the optimum angle and roughness.

Hereinafter, the operation of the lighting apparatus according to the present embodiment will be described with reference to FIG. 2.

When the laser sensor 5 detects the test piece 1, transfer starts up and down (S11). Next, it is determined whether the notch of the specimen 1 is detected (S12). If the notch is detected, the process proceeds to the next step. If the notch is not detected, it returns to the initial state and starts detection again. Next, measure the height of the specimen (1) and transmit the measurement results (S13). The lighting angle and the position of the illumination are calculated according to the position of the specimen 1 (S14). Data about the position of the illumination and the illumination angle is transmitted to the servo control device (S15). Drive the servo controller to adjust the lighting angle and position (S16). Next, it is determined whether or not the position shift completion signal is detected (S17). When the position shift complete signal is detected, the measurement ends (S18).

Therefore, the lighting device of the present embodiment solves the problems caused by the error in the setting process of the angle and illuminance of the illumination, thereby making the DWTT test more reliable.

The present invention described above can be embodied in many other forms without departing from the spirit or main features thereof. Therefore, the above embodiments are merely examples in all respects and should not be interpreted limitedly.

As described above, the present invention provides a lighting device that can obtain a better image results in the automated DWTT test evaluation apparatus of the image processing method and solves the problem caused by the error of the setting angle of the illumination angle and illumination In order to make the test method more reliable, in particular, it has the advantage of minimizing the test error caused in various kinds of test processes, thus providing the effect of generalization of the developed device.

Claims (6)

In the illumination device for detecting the ductile and brittle fracture surface of the DWTT specimen (1) fixed to the specimen holder (6), An A channel light (2) and a B channel light (3) installed on an upper portion of the support vertically installed at both ends of the specimen holder (6); A CCD camera (4) installed on the specimen (1) to photograph the fracture surface of the specimen (1); A rotation driving unit 16 installed on the support to rotate the respective lights 2 and 3; A linear driving unit (17) installed on the support for linearly moving the respective lights (2, 3) up and down; A laser sensor 5 installed to move up and down along a guide surface installed between the specimen 1 and the support to detect a fracture surface of the specimen 1; A linear driving unit 18 installed on the guide surface to linearly move the laser sensor 5 up and down; Lighting device for detecting a DWTT ductile and brittle fracture surface comprising a control unit for controlling the adjustment of the irradiation angle and the vertical position of the A, B channel illumination (2, 3) and the vertical position of the laser sensor (5) . The method of claim 1, And an illuminometer 19 installed on the side of the CCD camera 4 to measure illuminance of the reflected light, wherein the controller is configured to control the A, B channel illumination 2, according to the measurement result of the illuminometer 19. 3) DWTT ductile and brittle fracture detection apparatus for illumination, characterized in that to control the illuminance. The method according to claim 1 or 2, The control unit A light control unit 8 for controlling illuminance of the A and B channel lights 2 and 3; A light source irradiation angle servo controller (9) for controlling the rotation driving unit (16) for adjusting the irradiation angles of the A and B channel illuminations (2, 3); A light source shanghai servo controller (10) for controlling the linear driving unit (17) for moving the positions of the A and B channel lights (2, 3); A laser sensor shanghai song servo controller (11) for controlling the linear driving unit (18) for moving the position of the laser sensor (5); A laser measuring unit and driver 12 for controlling the detection of the laser sensor 5; And a transfer device control unit (14) for transmitting a control signal to said servo controller (9, 10, 11). The method according to claim 1 or 2, The A, B channel illumination (2, 3) is DWTT ductile and brittle fracture detection, characterized in that the illumination angle 20 is adjusted in the range of about 30 to 40 ° with respect to the center of the peak of the specimen (1) Lighting equipment. The method according to claim 1 or 2, The rotating drive unit 16 is a DWTT flexible and brittle fracture detection device for illumination, characterized in that the stepping motor. The method according to claim 1 or 2, DWTT flexible and brittle fracture surface detection apparatus, characterized in that the linear drive (17, 18) is a linear motor.

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