JP7299388B2 - Defect judgment device for the outer surface of iron pipes - Google Patents

Description

The present invention relates to a defect determination device for determining defects occurring on the outer surface of an iron pipe.

Detecting devices for detecting pipe cracks and the like are known. As such a detection device, for example, Patent Literature 1 discloses a crack detection device that detects cracks in a raw pipe of a pipe by image processing.

The crack detection device of Patent Document 1 includes an imaging device, a crack detection control device, and an image display device. The imaging device includes a magnetizing device, a test agent applicator, a rotation driving section, an illumination light source, an imaging section, and an imaging control section.

The magnetizing device energizes the pipe to magnetize the pipe. If there is a crack on the surface of the pipe, the magnetic force leaks from the crack, and the test agent adheres to it. The test drug applicator applies the test drug to the surface of the pipe. The rotation drive unit rotates the pipe while holding the pipe. The illumination light source is a linear light source capable of emitting uniform illumination light in the axial direction of the pipe. The imaging unit is composed of a one-dimensional CCD camera, and faces the pipe with a field of view in the axial direction of the pipe. The image pickup control section controls the image pickup operation of the image pickup section and the rotation operation of the rotation drive section to pick up a surface image of the entire circumference of the pipe.

If the surface of the pipe is damaged, the reflection angle of the reflected light changes, so the amount of light received by the imaging unit changes. As a result, a change in gradation occurs in the captured image. The crack detection device can detect a flaw based on a change in gradation of the captured image.

JP-A-2002-324233

The crack detection device disclosed in Patent Document 1 can detect cracks in a pipe. However, defects other than cracks may develop on the outer surface of the tube. For example, tube defects include linear defects, depressions or protrusions having a predetermined area, point defects, and the like. Defects other than these cracks cannot be clearly displayed in the captured image even if the linear light source is arranged in the axial direction of the tube as in the crack detection device disclosed in Patent Document 1 above. Therefore, defects other than cracks cannot be detected with high accuracy.

SUMMARY OF THE INVENTION An object of the present invention is to obtain a configuration capable of determining various types of defects on the outer surface of an iron pipe in a defect determination device for determining defects on the outer surface of the iron pipe.

An apparatus for determining defects on the outer surface of an iron pipe according to one embodiment of the present invention includes: a light source unit that irradiates the outer surface of an iron pipe with planar light; An image acquisition unit that acquires an image of a portion irradiated with light, and a defect determination unit that determines defects on the outer surface of the iron pipe using the image acquired by the image acquisition unit. The light source unit is positioned side by side with the image acquisition unit in the axial direction of the iron pipe when viewing the iron pipe in the radial direction, and intersects the outer surface of the iron pipe in the radial direction of the iron pipe. It is arranged at a position where the planar light is emitted in the direction of the light (first configuration).

The outer surface of the iron pipe is irradiated with planar light in a direction that intersects the radial direction of the iron pipe from the image acquisition unit and the light source unit positioned side by side in the axial direction of the iron pipe when the iron pipe is viewed in the radial direction. By doing so, shadows can be created around the defects in the outer surface. Thereby, a clear image of the defect can be obtained by the image obtaining unit. Therefore, the image acquired by the image acquisition unit can be used to accurately determine defects on the outer surface of the iron pipe.

The said 1st structure WHEREIN: The said light source part is arrange|positioned in the position adjacent to the said image acquisition part in the axial direction of the said iron pipe (2nd structure).

By irradiating the outer surface of the iron pipe with planar light in a direction intersecting the radial direction of the iron pipe from a light source unit positioned adjacent to the image acquisition unit in the axial direction of the iron pipe, Shadows can be more reliably cast around surface imperfections. Therefore, the image acquired by the image acquisition unit can be used to more accurately determine defects on the outer surface of the iron pipe.

In the first configuration, the light source section is arranged on one side of the iron pipe in the axial direction with respect to the image acquisition section (third configuration).

By arranging the light source unit on one side of the iron pipe in the axial direction with respect to the image acquisition unit, the light source unit can prevent defects on the outer surface of the iron pipe from the one side in the axial direction. of light can be emitted. Therefore, shadows are more likely to occur around the defect. Therefore, the image acquisition unit can acquire an image in which the defect is displayed more clearly.

In the first configuration, the light source unit is arranged so as to irradiate the outer surface of the iron pipe with the planar light in a tangential direction of the outer surface when the iron pipe is viewed in an axial direction. (Fourth configuration).

By irradiating the outer surface of the iron pipe with planar light in the tangential direction of the outer surface from the light source unit when the iron pipe is viewed in the axial direction, shadows are more reliably cast around the defects on the outer surface. can be made. Accordingly, an image in which the outline of the defect is displayed more clearly can be acquired by the image acquisition unit. Therefore, using the image acquired by the image acquisition unit, defects on the outer surface of the iron pipe can be determined with higher accuracy.

In any one of the first to fourth configurations, the iron pipe has, on its outer surface, a plurality of protrusions radially protruding beyond the defect. The image acquisition unit acquires an image of the outer surface of the iron pipe from a direction perpendicular to the axis of the iron pipe (fifth configuration).

As a result, a clearer image including the defect can be acquired without the defect being hidden by the convex portion (peening) formed on the outer surface of the iron pipe.

Moreover, as described above, the image acquiring section acquires the image from the direction orthogonal to the axis of the iron pipe, so that the image acquiring section can acquire the widest possible image of the iron pipe. Therefore, it is possible to efficiently acquire an image of the outer surface of the iron pipe.

In the fifth configuration, the image acquisition unit is positioned above or laterally to the iron pipe (sixth configuration). This can prevent dust from accumulating on the image acquisition unit. Therefore, a clearer image of the outer surface of the iron pipe can be obtained by the image obtaining section.

In the first configuration, the defect determination section has a determination reference data acquisition section that acquires determination reference data for determining defects on the outer surface of the iron pipe. The criterion data acquisition unit acquires the criterion data from the image data of the outer surface of the iron pipe having the defect using a plurality of image acquisition regions corresponding to the defect pattern (seventh configuration).

As a result, it is possible to acquire the optimum criterion data according to the pattern of defects peculiar to iron pipes. Therefore, since the accuracy of the determination reference data used in the defect determination section can be improved, the defect determination section can accurately determine defects on the outer surface of the iron pipe.

In the seventh configuration, the plurality of image acquisition areas include a first image acquisition area used to acquire the determination reference data when the defect on the outer surface of the iron pipe is a linear defect that is long in one direction; A second image acquisition area used to acquire the determination reference data when the defect on the outer surface of the iron pipe is a recess or protrusion having a predetermined area, and the defects on the outer surface of the iron pipe are scattered within a predetermined range. and a third image acquisition area used to acquire the determination reference data in the case of a point-like defect (eighth configuration).

As a result, three types of image acquisition can be performed according to the three types of defects unique to iron pipes (linear defects that are long in one direction, concave or convex portions that have a predetermined area, and point defects that are scattered within a predetermined range). Regions can be used to obtain criteria data. That is, for example, if the defect is a linear defect that is long in one direction, the determination criterion data is acquired using the elongated frame-shaped first image acquisition area, and if the defect is a recess or protrusion having a predetermined area , the determination reference data is acquired using the rectangular second image acquisition area, and in the case of a point defect in which the defect is scattered within a predetermined range, the determination is made using the rectangular third image acquisition area Get reference data.

Therefore, since the accuracy of the determination reference data used in the defect determination section can be improved, the defect determination section can accurately determine defects on the outer surface of the iron pipe.

The first configuration further includes a moving unit capable of moving the light source and the image acquisition unit in the axial direction of the iron pipe (ninth configuration).

By acquiring an image of the outer surface of the iron pipe while moving the light source and the image acquisition unit in the axial direction with respect to the iron pipe, the image of the outer surface of the iron pipe can be obtained in the axial direction without increasing the size of the defect determination device. can be obtained efficiently and easily. Moreover, since the moving unit for moving the light source and the image acquisition unit in the axial direction is more compact than the configuration for moving the iron pipe in the axial direction, the entire defect determination apparatus can be made compact.

In the ninth configuration, the moving section is configured to be able to move the light source section and the image acquisition section in the axial direction of the iron pipe from the insertion side of the iron pipe toward the socket side. The light source is positioned closer to the receptacle side in the axial direction than the image acquisition unit, and the optical axis of the light source extends obliquely from the receptacle side toward the receptacle side with respect to the axis of the iron pipe. are arranged as follows (tenth configuration).

The image acquisition unit and the light source unit located closer to the insertion port side in the axial direction than the image acquisition unit are moved in the axial direction of the iron pipe from the insertion port side toward the socket side, and the light source unit is moved along the optical axis. By arranging the iron pipe so as to obliquely extend from the insertion port side toward the socket side with respect to the axis of the iron pipe, the inclined portion between the socket and the straight pipe portion of the iron pipe and the vicinity thereof are the light sources. A clear image of the defect in the slanted portion can be captured by the image capture portion while being illuminated by the portion. Therefore, it is possible to accurately determine the defect of the inclined portion using the image.

The first configuration further includes an iron pipe rotating portion that rotates the iron pipe around its axis (eleventh configuration). By acquiring an image of the outer surface of the iron pipe while rotating the iron pipe, it is possible to easily acquire an image of the iron pipe in the circumferential direction.

In the apparatus for determining defects on the outer surface of an iron pipe according to one embodiment of the present invention, the light source unit that irradiates the outer surface of the iron pipe with planar light is an image acquisition unit that irradiates the iron pipe in the axial direction of the iron pipe. They are positioned adjacent to each other and are arranged at positions that irradiate planar light onto the outer surface of the iron pipe in a direction crossing the radial direction of the iron pipe.

This allows shadows to be created around defects in the outer surface of the iron pipe. Therefore, a clear image of the defect can be acquired by the image acquisition section positioned adjacent to the light source section in the axial direction of the iron pipe. Therefore, the image acquired by the image acquisition unit can be used to accurately determine defects on the outer surface of the iron pipe.

FIG. 1 is a diagram showing a schematic configuration of a defect determination device according to Embodiment 1. FIG. FIG. 2 is a block diagram schematically showing the configuration of the defect determination section. FIG. 3 is a diagram showing an example of criterion image data including defects on the outer surface of an iron pipe. FIG. 4 is a diagram showing a schematic configuration of a defect determination device according to the second embodiment. FIG. 5 is a diagram showing the relationship between the moving direction of the moving unit of the defect determination device according to the second embodiment and the iron pipe. FIG. 6 is a diagram showing a schematic configuration of a defect determination device according to another embodiment. FIG. 7 is a diagram showing a schematic configuration of a defect determination device according to another embodiment. FIG. 8 is a diagram showing a schematic configuration of a defect determination device according to another embodiment.

Each embodiment will be described below with reference to the drawings. In each figure, the same parts are denoted by the same reference numerals, and the description of the same parts will not be repeated. Note that the dimensions of the constituent members in each drawing do not faithfully represent the actual dimensions of the constituent members, the dimensional ratios of the respective constituent members, and the like.

In the following description, the vertical direction means the vertical direction with respect to the iron pipe W in which the iron pipe W to be subjected to defect judgment by the defect judging devices 1, 100, 200, 300, and 400 is arranged so that the axis P extends in the horizontal direction. do. The axial direction means the direction in which the axis P of the iron pipe W extends. The radial direction means a direction perpendicular to the axis P of the iron pipe W, that is, the radial direction of the iron pipe W.

In addition, in the following description, expressions such as “fixed”, “connected” and “attached” (hereinafter referred to as “fixed”) are used not only when members are directly fixed to each other, but also when they are fixed via other members. It also includes cases where it is fixed. That is, in the following description, expressions such as fixing include meanings such as direct and indirect fixing between members.

[Embodiment 1]
(overall structure)
FIG. 1 is a diagram showing a schematic configuration of a defect determination device 1 according to Embodiment 1 of the present invention. The defect determination device 1 determines whether or not there is a defect on the outer surface Wa of the iron pipe W, and also determines the type of the defect. The defect determination device 1 may determine only the presence or absence of defects on the outer surface Wa of the iron pipe W, or may determine only the types of the defects.

As shown in FIG. 3, the iron pipe W has a plurality of protrusions X (peening) on the outer surface Wa. The plurality of protrusions X form peening on the outer surface Wa of the iron pipe W. As shown in FIG. FIG. 3 is an example of an image of the outer surface Wa of the iron pipe W acquired by the image acquisition unit 11, which will be described later. In addition, in FIG. 3, the convex portion X is shown only on a part of the outer surface Wa of the iron pipe W, but the convex portion X is provided on the entire outer surface Wa of the iron pipe W. As shown in FIG.

The convex portion X is a fine convex shape having a curvature smaller than the curvature of the outer surface Wa of the iron pipe W. As shown in FIG. The amount of radial projection of the iron pipe W at the convex portion X is, for example, greater than the amount of radial projection of the iron pipe W at the defect on the outer surface Wa. The iron pipe W is, for example, a ductile iron pipe. Note that the iron pipe W may be an iron pipe other than the ductile iron pipe.

As shown in FIG. 1 , the defect determination device 1 has an image acquisition section 11 , a light source section 12 and a defect determination section 30 .

The image acquisition unit 11 acquires an image of the outer surface Wa of the iron pipe W. As shown in FIG. The image acquisition unit 11 includes, for example, an imaging device such as a CCD camera. The image acquired by the image acquisition unit 11 is output to the defect determination unit 30 as image data. Note that the image acquisition unit 11 may be an imaging device other than a CCD camera.

The image acquisition unit 11 is positioned in a direction perpendicular to the axis P of the iron pipe W with respect to the outer surface Wa of the iron pipe W. As shown in FIG. In this embodiment, the image acquisition unit 11 is positioned above the iron pipe W. As shown in FIG. The image acquisition unit 11 acquires an image of the outer surface Wa of the iron pipe W from a direction perpendicular to the axis P of the iron pipe W (radial direction of the iron pipe W).

The light source unit 12 irradiates planar light onto a portion of the outer surface Wa of the iron pipe W where the image acquisition unit 11 acquires an image. The light source unit 12 includes, for example, an LED lighting device. The light source unit 12 may be a surface light source or a point light source as long as it emits planar light. The light source unit 12 may have one light source, or may have a plurality of light sources.

The light source unit 12 is positioned with respect to the outer surface Wa of the iron pipe W in a direction perpendicular to the axis P of the iron pipe W (radial direction of the iron pipe W). The light source unit 12 is arranged on one side of the iron pipe W in the axial direction with respect to the image acquisition unit 11 . The light source unit 12 is positioned side by side in the axial direction of the iron pipe W with respect to the image acquiring unit 11 when the iron pipe W is viewed in the radial direction. In this embodiment, the light source unit 12 is positioned above the iron pipe W. As shown in FIG. The light source unit 12 is arranged to irradiate planar light onto a portion of the outer surface Wa of the iron pipe W where the image acquisition unit 11 acquires an image. The light source unit 12 is arranged so that the optical axis L extends in a direction intersecting the radial direction of the iron pipe W. As shown in FIG.

In the present embodiment, the light source unit 12 is positioned adjacent to the image acquisition unit 11 in the axial direction of the iron pipe W, and intersects the outer surface Wa of the iron pipe W in the radial direction of the iron pipe W. It is arranged at a position to irradiate planar light in the direction of the light. The optical axis L of the light source unit 12 also intersects the axis P of the iron pipe W. As shown in FIG.

In general, the dimension (depth) in the radial direction of the iron pipe W is smaller than that of defects, such as flaws and stains formed on the outer surface Wa of the iron pipe W on a non-defective product. Therefore, as described above, by irradiating planar light from the light source unit 12 in a direction crossing the radial direction of the iron pipe W, shadows are less likely to occur on flaws, stains, and the like of the non-defective product. Thereby, the defect determination apparatus 1 can create a shadow only around the defect on the outer surface Wa of the iron pipe W. FIG. Therefore, the image acquisition unit 11 can acquire an image in which the outline of the defect is clearly displayed. The flaws on the non-defective product include scratches and NO. , etc., and does not affect the function of the iron pipe W.

In addition, when the outer surface Wa of the iron pipe W is irradiated with light in the radial direction of the iron pipe W, the light enters the defect of the outer surface Wa of the iron pipe W. As shown in FIG. Therefore, from the image of the outer surface Wa of the iron pipe W acquired by the image acquisition unit 11 in a state where the outer surface Wa of the iron pipe W is irradiated with light in the radial direction of the iron pipe W, the defect can be clearly identified. is difficult.

The defect determination unit 30 determines defects on the outer surface Wa of the iron pipe W using the image of the outer surface Wa of the iron pipe W acquired by the image acquisition unit 11 . The defect determination unit 30 detects defects on the outer surface Wa of the iron pipe W and also determines the types of the defects. The defect determination unit 30 has a learning function of performing machine learning of defects on the outer surface Wa of the iron pipe W, for example, by acquiring data on defects on the outer surface Wa of the iron pipe W as determination reference data.

FIG. 2 is a block diagram showing a schematic configuration of the defect determination section 30. As shown in FIG. As shown in FIG. 2 , the defect determination section 30 has a determination reference data acquisition section 31 , a determination execution section 32 and a determination result output section 33 .

The determination reference data acquisition unit 31 acquires determination reference data including image data regarding defects on the outer surface Wa of the iron pipe W. As shown in FIG. Specifically, the determination reference data acquisition unit 31 associates the reference image data DR of the defect of the outer surface Wa of the iron pipe W obtained from the determination reference image data with the information on the type of the defect, thereby obtaining the above-described Get the criteria data. That is, the criterion data includes defect reference image data DR and information on the type of the defect.

The determination reference data acquisition unit 31 uses a plurality of image acquisition regions R1 to R3 corresponding to the defect pattern to obtain reference image data DR of the defect from the determination reference image data including the defect of the outer surface Wa of the iron pipe W. get. The determination reference image data including defects on the outer surface Wa of the iron pipe W may be acquired by the image acquisition unit 11, may be acquired by another image acquisition device, or may be stored in a storage device, network, or the like. image data.

The defect reference image data DR is image data in which an image includes a characteristic defect shape corresponding to the type of defect on the outer surface Wa of the iron pipe W. FIG.

The plurality of image acquisition regions R1 to R3 differ according to defects on the outer surface Wa of the iron pipe W. As shown in FIG. In general, the defects on the outer surface Wa of the iron pipe W are linear defects (hereinafter referred to as linear defects) long in one direction such as a hot water boundary or a crack, and a predetermined area such as a melt spill. It includes defects that are recesses or protrusions having a surface, and point-like defects that are scattered within a predetermined range, such as rough skin or pinholes. Therefore, the shapes of the plurality of image acquisition regions R1 to R3 differ according to the shape and characteristics of the defect on the outer surface Wa of the iron pipe W. The predetermined area means an area larger than the area of the point-like defect.

FIG. 3 is a diagram showing an example of the criterion image data D including defects on the outer surface Wa of the iron pipe W. As shown in FIG. For the sake of explanation, the reference image data D shown in FIG. 3 includes images of a plurality of types of defects. An image of the defect is included. The judgment reference image data D may include images of a plurality of types or a plurality of defects.

As indicated by the dashed lines in FIG. 3, the plurality of image acquisition regions R1 to R3 are composed of a first image acquisition region R1 elongated in one direction used in the case of a linear defect, and a concave or convex defect having a predetermined area. It includes a rectangular second image acquisition region R2 used in the case of a defect and a relatively large third image acquisition region R3 used in the case of a point defect.

The first image acquisition region R1, the second image acquisition region R2, and the third image acquisition region R3 are each set on the judgment reference image data D so as to surround part or all of the defect. At least one of the first image acquisition area R1, the second image acquisition area R2 and the third image acquisition area R3 may surround the defect with a plurality of areas depending on the size of the defect.

The determination reference data acquisition unit 31 uses the image acquisition regions R1 to R3 of each type described above to obtain the reference image data DR of the defect (indicated by the broken line in FIG. 3) from the determination reference image data D of the outer surface Wa of the iron pipe W. image data of the enclosed part). That is, the determination reference data acquisition unit 31 acquires an image of a region surrounded by the plurality of image acquisition regions R1 to R3 in the determination reference image data D as the reference image data DR. As described above, since the plurality of image acquisition regions R1 to R3 include a plurality of types of image acquisition regions R1 to R3 corresponding to the types of defects, the determination reference data acquisition unit 31 obtains reference image data of defects. DR can be obtained with high accuracy.

The information about the defect type may be input to the determination reference data acquisition unit 31 separately from the defect reference image data DR, or the determination reference data acquisition unit 31 may acquire the defect reference image data DR. It may be acquired from a storage device, database, or the like (not shown) at the time of processing.

The determination execution unit 32 uses the determination reference data acquired by the determination reference data acquisition unit 31 and the image data of the outer surface Wa of the iron pipe W acquired by the image acquisition unit 11 to determine the outer surface Wa of the iron pipe W. , and if there is a defect, determine the type of the defect. Specifically, the determination execution unit 32 determines whether or not the image data of the outer surface Wa of the iron pipe W acquired by the image acquisition unit 11 includes a portion whose characteristics match the image of the defect in the determination reference data. judge. A determination result of the determination execution unit 32 is output to the determination result output unit 33 .

Note that the determination execution unit 32 uses, for example, the brightness, chromaticity, and saturation of pixels in the image data and their position information to match the image data with the image of the defect in the determination reference data. Determine if a part exists. The determination execution unit 32 may determine whether or not the image data includes a portion whose characteristics match those of the image of the defect in the determination reference data, using another method.

The determination execution unit 32 may extract data of a predetermined image acquisition area from the image data, and obtain a matching rate between the extracted data and the determination reference data. The predetermined image acquisition area may be different depending on the defect pattern, for example, like the image acquisition areas R1 to R3 used in the criterion data acquisition unit 31, or may be the same regardless of the defect pattern. may The determination execution unit 32 may determine that the image data includes a portion whose features match the image of the defect in the determination reference data when the matching rate is equal to or greater than a threshold. The determination execution unit 32 may combine a plurality of data obtained from the image acquisition areas and obtain a match rate with the determination reference data.

The determination result output unit 33 outputs the determination result of the determination execution unit 32 to a display or the like as output data including at least one of character information and image information, for example. The determination result output unit 33 may output the reliability of determination by the determination execution unit 32 . The determination result output unit 33 may output the output data to another device, or may output the determination result of the determination execution unit 32 by printing it on paper or the like.

As described above, the iron pipe outer surface defect determination apparatus 1 according to the present embodiment includes the light source unit 12 that irradiates the outer surface Wa of the iron pipe W with planar light, and the light source unit 12 of the outer surface Wa of the iron pipe W. Using the image acquisition unit 11 for acquiring the image of the portion irradiated with the planar light by and the image acquired by the image acquisition unit 11, the defect determination unit 30 for determining defects on the outer surface Wa of the iron pipe W And prepare. The light source unit 12 is positioned side by side with the image acquiring unit 11 in the axial direction of the iron pipe W when the iron pipe W is viewed in the radial direction, and intersects the outer surface of the iron pipe W in the radial direction of the iron pipe W. It is arranged at a position where the planar light is emitted in the direction of the light.

With respect to the outer surface Wa of the iron pipe W, from the image acquisition unit 11 and the light source unit 12 positioned side by side in the axial direction of the iron pipe W when viewed in the radial direction of the iron pipe W, a planar image in a direction intersecting the radial direction of the iron pipe W , a shadow can be formed around the defect on the outer surface Wa. Accordingly, the image acquisition unit 11 can acquire a clear image of the defect. Further, by irradiating the outer surface Wa of the iron pipe W with planar light as described above, the brightness of the outer surface Wa of the iron pipe W can be made more uniform. As a result, defects on the outer surface Wa of the iron pipe W can be determined more efficiently than when the outer surface Wa of the iron pipe W is dark. Therefore, by using the image acquired by the image acquisition unit 11, the defect of the outer surface Wa of the iron pipe W can be accurately and efficiently determined.

The flaws, stains, and the like formed on the outer surface Wa of the iron pipe W are smaller in the radial direction (depth) of the iron pipe W than the defects. Therefore, as described above, by irradiating planar light from the light source unit 12 in a direction crossing the radial direction of the iron pipe W, shadows are less likely to occur on flaws, stains, and the like of the non-defective product. As a result, the defect determination apparatus 1 shades only the defect on the outer surface Wa of the iron pipe W, and can obtain a clear image of the defect.

In addition, when the outer surface Wa of the iron pipe W is irradiated with light in the radial direction of the iron pipe W, the defect does not cast a shadow as well as the scratches and stains of the non-defective product, so that only the defect is clearly projected. It is difficult.

In this embodiment, the light source unit 12 is arranged at a position adjacent to the image acquisition unit 11 in the axial direction of the iron pipe W. As shown in FIG.

The outer surface Wa of the iron pipe W is irradiated with planar light in a direction crossing the radial direction of the iron pipe W from the light source unit 12 positioned adjacent to the image acquisition unit 11 in the axial direction of the iron pipe W. Thus, shadows can be reliably formed around defects on the outer surface Wa. Accordingly, the image acquisition unit 11 can acquire a clear image of the defect. Therefore, the image acquired by the image acquisition unit 11 can be used to determine defects on the outer surface Wa of the iron pipe W with higher accuracy.

In this embodiment, the light source unit 12 is arranged on one side of the iron pipe W in the axial direction with respect to the image acquisition unit 11 .

Since the light source unit 12 is arranged on one side of the iron pipe W in the axial direction with respect to the image acquisition unit 11, the light source unit 12 can detect defects on the outer surface Wa of the iron pipe W in the axial direction. Light can be emitted from one side. Therefore, shadows are more likely to occur around the defect. Therefore, the image acquisition unit 11 can acquire an image in which the defects are displayed more clearly.

In this embodiment, the iron pipe W has a plurality of projections X on the outer surface Wa, which protrude in the radial direction of the iron pipe W to a greater extent than the defects. The image acquisition unit 11 acquires an image of the outer surface Wa of the iron pipe W from a direction perpendicular to the axis P of the iron pipe W. As shown in FIG. It should be noted that the protrusion X may protrude from the defect to any extent as long as it protrudes in the radial direction beyond the defect.

As a result, the defects are not hidden by the protrusions X (peening) formed on the outer surface Wa of the iron pipe W, and a clearer image including the defects can be obtained.

Moreover, the image acquisition unit 11 acquires images of the iron pipe W in the direction orthogonal to the axis P of the iron pipe W as described above, so that the image acquisition unit 11 can acquire an image of the iron pipe W as wide as possible. Therefore, the image of the outer surface Wa of the iron pipe W can be acquired efficiently.

In this embodiment, the image acquisition unit 11 is positioned above the iron pipe W. As shown in FIG. This can prevent dust from accumulating on the image acquisition unit 11 . Therefore, a clearer image of the outer surface Wa of the iron pipe W can be acquired by the image acquisition unit 11 .

In this embodiment, the defect determination unit 30 has a determination reference data acquisition unit 31 that acquires determination reference data for determining defects on the outer surface Wa of the iron pipe W. As shown in FIG. The determination reference data acquisition unit 31 acquires the determination reference data from the image data of the outer surface Wa of the iron pipe W having the defect using a plurality of image acquisition regions R1 to R3 corresponding to the defect pattern.

This makes it possible to acquire the optimum determination reference data according to the pattern of defects peculiar to the iron pipe W. Therefore, since the accuracy of the determination reference data used in the defect determination unit 30 can be improved, the defect determination unit 30 can determine defects on the outer surface Wa of the iron pipe W with high accuracy.

In the present embodiment, the plurality of image acquisition regions R1 to R3 are a first image acquisition region R1 used for acquiring determination reference data when the defect on the outer surface Wa of the iron pipe W is a linear defect that is long in one direction, A second image acquisition region R2 used to acquire the determination reference data when the defect on the outer surface Wa of the iron pipe W is a concave portion or a convex portion having a predetermined area, and a defect on the outer surface Wa of the iron pipe W within a predetermined range. and a third image acquisition region R3 used to acquire the determination reference data in the case of a point-like defect scattered within.

As a result, three types of images are generated according to three types of defects peculiar to the iron pipe W (linear defects long in one direction, concave or convex portions having a predetermined area, and point defects scattered within a predetermined range). The determination reference data can be acquired using the acquisition regions R1 to R3. That is, for example, when the defect is a linear defect that is long in one direction, the determination reference data is acquired using the elongated frame-shaped first image acquisition region R1, and the defect is a concave or convex portion having a predetermined area. In this case, the determination reference data is acquired using the rectangular second image acquisition region R2. Determination reference data is acquired using the third image acquisition region R3.

Therefore, since the accuracy of the determination reference data used in the defect determination unit 30 can be improved, the defect determination unit 30 can determine defects on the outer surface Wa of the iron pipe W with high accuracy.

(Modification 1 of Embodiment 1)
In the first embodiment described above, the light source unit 12 is positioned adjacent to the image acquisition unit 11 in the axial direction of the iron pipe W, and is positioned adjacent to the image acquisition unit 11 with respect to the iron pipe W in the radial direction of the iron pipe W with respect to the outer surface Wa of the iron pipe W. It is arranged in a position to irradiate light in a direction intersecting with the

However, as shown in FIG. 7, the light source unit 312 is positioned side by side with the image acquisition unit 11 in the axial direction of the iron pipe W when the iron pipe W is viewed in the radial direction, and is positioned relative to the outer surface Wa of the iron pipe W. It may be arranged at a position that irradiates light in a direction intersecting with the radial direction of W. The light source unit 312 may be arranged so that the angle of incidence (the angle formed by the optical axis L and the radial direction of the iron pipe W) with respect to the outer peripheral surface of the iron pipe W is an acute angle, or may be arranged at an obtuse angle as shown in FIG. may be arranged so as to be Further, the light source unit 312 may be positioned at the same position in the radial direction of the iron pipe W with respect to the image acquisition unit 11, or may be positioned at a different position as shown in FIG.

Even when the light source unit 312 is arranged as described above, the planar light emitted from the light source unit 312 onto the outer surface Wa of the iron pipe W can cast a shadow on the defects on the outer surface Wa of the iron pipe W. As a result, the defect determination device 300 can obtain a clear image of defects on the outer surface Wa of the iron pipe W. FIG.

(Modification 2 of Embodiment 1)
As shown in FIG. 8 , the light source unit 412 is positioned side by side with the image acquisition unit 11 in the axial direction of the iron pipe W when the iron pipe W is viewed in the radial direction, and is positioned closer to the outer surface Wa of the iron pipe W than the image acquisition unit 11 is. and the optical axis L is parallel to the axis P of the iron pipe W. Thereby, the outer surface Wa of the iron pipe W is irradiated with the light emitted from the light source unit 412 . The light source unit 412 may be positioned at the same position in the radial direction of the iron pipe W with respect to the image acquisition unit 11, or may be positioned at a different position as shown in FIG.

Even when the light source unit 412 is arranged as described above, the planar light irradiated to the outer surface Wa of the iron pipe W by the light source unit 412 can cast a shadow on the defects on the outer surface Wa of the iron pipe W. Thereby, the defect determination device 400 can obtain a clear image of the defect on the outer surface Wa of the iron pipe W. FIG.

The optical axis L is parallel to the axis P of the iron pipe W not only when the optical axis L and the axis P are completely parallel, but also when the extension of the optical axis L intersects the axis P. A case where the optical axis L or the axis P is tilted is also included.

[Embodiment 2]
FIG. 4 shows a schematic configuration of a defect determination device 100 according to the second embodiment. A defect determination device 100 of the present embodiment differs from the defect determination device 1 of the first embodiment in that it has a moving section 110 and an iron pipe rotating section 120 . In the following description, the same reference numerals are assigned to the same configurations as in the first embodiment, and the description thereof is omitted, and only the portions different from the configuration of the first embodiment will be described.

The defect determination device 100 has a moving section 110 and an iron pipe rotating section 120 . The moving unit 110 moves the image acquisition unit 11 and the light source unit 12 in the axial direction of the iron pipe W. As shown in FIG. The moving part 110 has a rail 111 extending in the axial direction of the iron pipe W, and a slider 112 moving on the rail 111 in the axial direction.

The rail 111 is arranged so as to extend along the axis P of the iron pipe W. As shown in FIG. That is, the extending direction of the rail 111 matches the axial direction of the iron pipe W. As shown in FIG.

In this embodiment, the slider 112 is provided below the rail 111 so as to be movable in the axial direction. The slider 112 is movable in the axial direction along the rail 111 by a driving device (not shown). The driving device may be a device with a conveyor belt, a device with a cylinder, or a device with wheels provided on the slider 112 . The drive device may have any configuration as long as it has a configuration that allows the slider 112 to move along the rail 111 in the axial direction.

The image acquisition section 11 and the light source section 12 are attached to the slider 112 . Thereby, the image acquisition unit 11 and the light source unit 12 can move in the axial direction along the rails 111 . Therefore, the image acquisition unit 11 and the light source unit 12 can be moved with respect to the iron pipe W in the axial direction.

In this embodiment, the defect determination apparatus 100 has the moving unit 110, so that the image of the outer surface Wa of the iron pipe W can be acquired while moving the light source unit 12 and the image acquisition unit 11 with respect to the iron pipe W in the axial direction. can be done. Therefore, the defect determination apparatus 100 can efficiently and easily acquire an image of the outer surface Wa of the iron pipe W over the axial direction without increasing the size. Moreover, since the movement unit 110 that moves the light source unit 12 and the image acquisition unit 11 in the axial direction is more compact than a configuration that moves the iron pipe W in the axial direction, the entire defect determination apparatus 100 can be miniaturized.

It is preferable that the moving unit 110 can move the light source unit 12 and the image acquisition unit 11 at least in the axial direction of the iron pipe W from the insertion opening W1 side of the iron pipe W toward the socket W2 side. The light source unit 12 is positioned adjacent to the image acquisition unit 11 in the axial direction of the iron pipe W, and emits light to the outer surface Wa of the iron pipe W in a direction intersecting the radial direction of the iron pipe W. placed in the position to be irradiated. In the example shown in FIG. 5, the light source unit 12 is positioned closer to the insertion port W1 in the axial direction of the iron pipe W than the image acquisition unit 11, and the optical axis L of the light source unit 12 is inserted with respect to the axis P of the iron pipe W. It is arranged so as to obliquely extend from the mouth W1 side toward the socket W2 side. The optical axis L of the light source unit 12 intersects the axis P of the iron pipe W so as to fall toward the insertion opening W1 with respect to the vertical line. The light source unit 12 is arranged such that the incident angle of light with respect to the axis P is greater than 0 degree.

By moving the light source unit 12 arranged in this manner in the axial direction of the iron pipe W from the insertion port W1 side of the iron pipe W toward the socket W2 side, the light source unit 12 is moved to the socket W2. It is possible to irradiate light at an angle closer to the normal to the slope Wb located on the pipe body side. Therefore, the defect determination apparatus 100 can acquire a clear image of the slope Wb and its vicinity by the image acquisition unit 11, and can accurately detect defects on the slope Wb and its vicinity.

Note that the moving unit 110 may move the light source unit 12 and the image acquisition unit 11 in the axial direction of the iron pipe W from the socket W2 side of the iron pipe W toward the insertion opening W1 side. In this case, the light source unit 12 may be positioned on the socket W2 side of the iron pipe W in the axial direction of the iron pipe W with respect to the image acquisition unit 11 .

The iron pipe rotating part 120 rotates the iron pipe W around the axis P while supporting the iron pipe W. The iron pipe rotating portion 120 has a rotation support portion 121 . The rotation support part 121 has a roller (not shown) that rotates the iron pipe W, and a rotation drive part that rotates the roller. The configuration of the rotation support portion 121 may be a configuration other than the roller as long as it is configured to rotate the iron pipe W around the axis P.

In the present embodiment, the defect determination apparatus 100 includes the iron pipe rotating unit 120, so that the image acquisition unit 11 can acquire an image of the outer surface Wa of the iron pipe W while rotating the iron pipe W. Therefore, the defect determination apparatus 100 can easily acquire an image of the iron pipe W in the circumferential direction.

(Other embodiments)
Although the embodiments of the present invention have been described above, the above-described embodiments are merely examples for carrying out the present invention. Therefore, without being limited to the above-described embodiment, it is possible to modify the above-described embodiment as appropriate without departing from the spirit thereof.

In each of the embodiments described above, the image acquisition unit 11 and the light source unit 12 are positioned above the iron pipe W. As shown in FIG. However, the image acquisition section and the light source section may be positioned on the side of the iron pipe. Also, in the case of a defect determination device used in a work environment with little dust, or in the case of a defect determination device equipped with a device capable of removing dust accumulated on the image acquisition unit, the image acquisition unit and the light source unit It may be located below the iron pipe. Further, the image acquisition section and the light source section may be arranged in an oblique direction with respect to the iron pipe when the iron pipe is viewed in the axial direction.

In each of the embodiments described above, the defect determination devices 1 , 100 , 200 have the light source units 12 , 212 . However, the defect determination device may have a plurality of light source units. The plurality of light source units may be arranged so as to emit planar light in a plurality of directions with respect to the iron pipe.

In each of the above-described embodiments, the light source unit 12 is arranged on one side of the iron pipe W in the axial direction with respect to the image acquisition unit 11 . However, the light source section may be arranged on the other side of the iron pipe in the axial direction with respect to the image acquisition section. That is, the light source section may be arranged on the socket side of the iron pipe with respect to the image acquisition section.

In each of the above-described embodiments, the image acquisition unit 11 and the light source unit 12 are arranged in the axial direction of the iron pipe W. As shown in FIG. However, the position of the image acquisition section and the position of the light source section may be shifted in the circumferential direction of the iron pipe W.

In each of the above-described embodiments, the iron pipe W whose defect is judged by the defect judging apparatus 1, 100 has a plurality of projections X on the outer surface Wa which have a larger amount of protrusion than the defect when viewed in the axial direction of the outer surface Wa of the iron pipe W. have However, the iron pipe may have protrusions only on a part of its outer surface, or may have no protrusions. The iron pipe may have recesses on its outer surface. The iron pipe may have a convex portion with the same amount of protrusion as the defect, or may have a convex portion with a smaller amount of protrusion than the defect when the outer surface of the iron pipe is viewed in the axial direction.

In each of the embodiments described above, the defect determination unit 30 has the determination reference data acquisition unit 31 . However, the defect determination section may not have the determination reference data acquisition section. In this case, the defect determination section may determine whether or not a defect exists in the image acquired by the image acquisition section, based on preset determination criteria.

In each of the above-described embodiments, the criterion data acquisition unit 31 acquires criterion data from the image data of the outer surface Wa of the iron pipe W having the defect using a plurality of image acquisition regions R1 to R3 corresponding to the defect. However, the criterion data acquisition unit may acquire the criterion data from the image data using four or more or two or less image acquisition regions depending on the defect. Further, the determination reference data acquisition unit may acquire the determination reference data from the image data using one or a plurality of image acquisition regions regardless of the type and size of the defect.

In each of the above-described embodiments, the light source unit 12 emits light above the iron pipe W and in a direction crossing the radial direction of the iron pipe W to a portion of the outer surface Wa of the iron pipe W where the image acquisition unit 11 acquires an image. are doing. However, the light source unit may irradiate light in a tangential direction to the outer peripheral surface of the iron pipe when the iron pipe is viewed in the axial direction.

For example, as shown in FIG. 6, the defect determination apparatus 200 has a light source unit 212 arranged in the tangential direction of the outer surface Wa of the iron pipe W and below the iron pipe W when the iron pipe W is viewed in the axial direction. As a result, the outer surface Wa of the iron pipe W can be irradiated with light in the tangential direction of the outer surface Wa of the iron pipe W when the iron pipe W is viewed in the axial direction. Therefore, shadows can be more reliably formed around defects on the outer surface Wa of the iron pipe W.

The image acquisition unit 11 is preferably arranged in a direction orthogonal to the axis P of the iron pipe W with respect to the portion irradiated with light from the light source unit 212 . As a result, the image acquisition unit 11 can acquire an image including a defect whose outline has been made clearer by the light source unit 212 .

Therefore, with the arrangement of the light source unit 212 and the image acquisition unit 11 as shown in FIG. can judge well.

In the second embodiment, the defect determination device 100 has the moving section 110 and the iron pipe rotating section 120 . However, the defect determination device does not have to have a moving part. The defect determination unit may not have the iron pipe rotation unit. The defect determination device does not have to have both the moving part and the iron pipe rotating part.

In the second embodiment, the moving section 110 moves the light source section 12 and the image acquiring section 11 in the axial direction of the iron pipe W. As shown in FIG. However, the moving unit may move only the image acquiring unit in the axial direction of the iron pipe.

INDUSTRIAL APPLICABILITY The present invention can be used for a defect determination device that determines defects on the outer surface of iron pipes.

1, 100, 200, 300, 400 defect determination device 11 image acquisition unit 12, 212, 312, 412 light source unit 30 defect determination unit 31 determination reference data acquisition unit 32 determination execution unit 33 determination result output unit 110 moving unit 111 rail 112 Slider 120 Iron pipe rotating part 121 Rotation support part W Iron pipe W1 Insertion opening W2 Receptacle Wa Outer surface Wb Slope P Axis line L Optical axis D Image data DR Reference image data R1 First image acquisition area R2 Second image acquisition area R3 Third image Acquisition area X Convex part

Claims (12)

one light source unit that irradiates planar light onto the outer surface of the iron pipe;
An image obtained by obtaining an image of a portion of the outer surface of the iron pipe irradiated with the planar light by the light source unit from a direction perpendicular to the axis of the iron pipe, obtained from a direction perpendicular to the axis of the iron pipe. an acquisition unit;
A defect determination unit that determines defects on the outer surface of the iron pipe using the image acquired by the image acquisition unit;
with
The light source unit is positioned side by side with the image acquisition unit in the axial direction of the iron pipe when viewing the iron pipe in the radial direction, and intersects the outer surface of the iron pipe in the radial direction of the iron pipe. is arranged at a position to irradiate the planar light in the direction of
Equipment for determining defects on the outer surface of iron pipes. In the defect determination device for the outer surface of the iron pipe according to claim 1,
The light source unit is arranged at a position adjacent to the image acquisition unit in the axial direction of the iron pipe,
Defect determination device for the outer surface of iron pipes. In the defect determination device for the outer surface of the iron pipe according to claim 1,
The light source unit is arranged on one side of the iron pipe in the axial direction with respect to the image acquisition unit,
Defect determination device for the outer surface of iron pipes. In the defect determination device for the outer surface of the iron pipe according to claim 1,
The light source unit is arranged so as to irradiate the surface of the iron pipe with the planar light in the tangential direction of the outer surface when the iron pipe is viewed in the axial direction.
Defect determination device for the outer surface of iron pipes. In the defect determination device for the outer surface of the iron pipe according to any one of claims 1 to 4,
The iron pipe has a plurality of protrusions on the outer surface that protrude radially beyond the defect,
The image acquisition unit acquires an image of the outer surface of the iron pipe from a direction perpendicular to the axis of the iron pipe,
Defect determination device for the outer surface of iron pipes. In the defect determination device for the outer surface of the iron pipe according to claim 5,
The image acquisition unit is positioned above or laterally with respect to the iron pipe,
Defect determination device for the outer surface of iron pipes. In the defect determination device for the outer surface of the iron pipe according to claim 1,
The defect determination unit
a determination reference data acquisition unit that acquires determination reference data for determining defects on the outer surface of the iron pipe using the image of the outer surface of the iron pipe acquired by the image acquisition unit;
The determination reference data acquisition unit obtains from the image data of the outer surface of the iron pipe that has a defect and is used when generating the determination reference data, the defect is an image having a different shape or size depending on the type of defect Acquiring reference image data that is included in an acquisition area, and acquiring the determination reference data by associating the reference image data with information about the type of the defect;
Defect determination device for the outer surface of iron pipes. In the defect determination device for the outer surface of the iron pipe according to claim 7,
The image acquisition area is
a first image acquisition area used to acquire the criterion data when the defect on the outer surface of the iron pipe is a linear defect that is long in one direction;
a third image acquisition area used to acquire the determination reference data when defects on the outer surface of the iron pipe are point-like defects scattered within a predetermined range;
When the defect on the outer surface of the iron pipe is a concave or convex portion having a predetermined area larger than the area of the point defect and a width larger than the linear defect, it is used to acquire the determination reference data a second image acquisition region,
including,
Defect determination device for the outer surface of iron pipes. In the defect determination device for the outer surface of the iron pipe according to claim 8,
The linear defect includes a weld boundary or a crack,
The concave or convex portion having the predetermined area includes a hot water spill,
The point-like defects include rough skin or pinholes,
Defect determination device for the outer surface of iron pipes. In the defect determination device for the outer surface of the iron pipe according to claim 1,
Further comprising a moving unit capable of moving the light source unit and the image acquisition unit in the axial direction of the iron pipe,
Defect determination device for the outer surface of iron pipes. In the defect determination device for the outer surface of the iron pipe according to claim 10,
The moving unit can move the light source unit and the image acquisition unit in the axial direction of the iron pipe from the insertion opening side of the iron pipe toward the socket side having an outer diameter larger than that of the insertion opening side. configured,
The light source unit is located closer to the insertion port side in the axial direction than the image acquisition unit, and the optical axis of the light source unit is oblique from the insertion port side toward the socket side with respect to the axis of the iron pipe. are arranged so as to extend to
Defect determination device for the outer surface of iron pipes. In the defect determination device for the outer surface of the iron pipe according to claim 1,
Further comprising an iron pipe rotating part that rotates the iron pipe about its axis,
Equipment for determining defects on the outer surface of iron pipes.

Images