JP6326939B2 - Flaw detector - Google Patents

Description

  The present invention relates to a flaw detection apparatus, and more particularly to a flaw detection apparatus that detects a tube defect.

  The tube is made of, for example, a synthetic resin or metal containing carbon fiber. In order to guarantee the quality of the tube, for example, it is conceivable to detect a tube defect by ultrasonic flaw detection and evaluate the tube quality based on the result.

  An example of the pipe is a seamless metal pipe. As a method for detecting a defect in the seamless metal pipe, for example, the following method can be considered.

  First, the defect of the seamless metal pipe moving on the transfer line is detected using the first flaw detector. When a defect is detected, the position where the defect is detected is marked. This identifies the approximate location of the defect. Subsequently, in order to perform detailed defect evaluation, the vicinity of the marking may be flawed by the second flaw detector. Thereby, the detailed position and size of the defect are specified.

  Japanese Unexamined Patent Publication No. 2013-174551 discloses an ultrasonic flaw detector. This ultrasonic flaw detector is used for inspecting a thinning situation occurring on the inner surface of the base of a nozzle connected to a header of a boiler. The ultrasonic flaw detector includes a main body block, a moving block, a probe, a coil spring, and a roller. The lower surface of the main body block has a curved surface similar to the arc-shaped surface to be inspected on the surface of the nozzle. The main body block is provided with a roller. The moving block is provided so as to be movable in the vertical direction with respect to the main body block. A probe is attached to the lower part of the moving block. The moving block is attached to the main body block via a coil spring.

  In the above publication, the thickness reduction state of the nozzle is inspected as follows. First, an operator places the ultrasonic flaw detector on the base of the nozzle. At this time, the roller is in contact with the outer surface of the nozzle. The axial direction of the roller coincides with the axial direction of the nozzle. Subsequently, an operator inspects the thinning state of the nozzle pedestal by oscillating ultrasonic waves from the probe while moving the ultrasonic flaw detector in the circumferential direction of the nozzle pedestal.

JP 2013-174551 A

  For example, it is assumed that the ultrasonic flaw detector described in the above publication is used as the second flaw detector for detecting a defect in a seamless metal tube. In this case, the ultrasonic flaw detector is placed on a seamless metal tube. At this time, the roller is in contact with the outer surface of the seamless metal tube. The axial direction of the roller coincides with the axial direction of the seamless metal pipe. The ultrasonic flaw detector identifies defects in the seamless metal tube while moving in the circumferential direction of the seamless metal tube.

  When the ultrasonic flaw detector is placed on the seamless metal tube, the ultrasonic flaw detector can move only in the circumferential direction of the seamless metal tube. Therefore, to move the ultrasonic flaw detector in the axial direction of the seamless metal tube, after separating the ultrasonic flaw detector from the seamless metal tube, the ultrasonic flaw detector is moved in the axial direction of the seamless metal tube, Again, it is necessary to place the ultrasonic flaw detector on a seamless metal tube. Therefore, it is difficult to easily perform an operation for identifying a defect in a seamless metal pipe.

  An object of the present invention is to provide a flaw detection apparatus that can easily perform an operation of identifying a defect of a tube.

  A flaw detection apparatus according to an embodiment of the present invention includes an apparatus main body, a detection element, a first rolling mechanism, a second rolling mechanism, and a switching mechanism. The device body can be placed on the surface of the tube. The detection element is provided in the apparatus main body and detects a defect of the tube. The first rolling mechanism is provided in the apparatus main body. The first rolling mechanism includes at least one sphere. The sphere is disposed in contact with the surface of the tube. The first rolling mechanism allows the sphere to roll in the axial and circumferential direction of the tube on the surface of the tube. The second rolling mechanism is provided in the apparatus main body. The second rolling mechanism includes at least one wheel. The wheel is disposed so as to be in contact with the surface of the pipe. The second rolling mechanism allows the wheel to roll in the axial direction of the tube on the surface of the tube. The switching mechanism is provided in the apparatus main body. The switching mechanism switches the operation mode by displacing one of the first rolling mechanism and the second rolling mechanism with respect to the apparatus main body. The operation mode includes a first operation mode and a second operation mode. In the first operation mode, the apparatus main body moves on the surface of the tube based on the first rolling mechanism. In the second operation mode, the apparatus main body moves on the surface of the tube based on the second rolling mechanism.

  The flaw detection apparatus according to the embodiment of the present invention can easily perform an operation of identifying a tube defect.

It is a top view which shows the flaw detection apparatus by embodiment of this invention. It is a flaw detection apparatus shown in FIG. 1, Comprising: It is a top view which shows the state which removed the cover. It is a bottom view of the flaw detection apparatus shown in FIG. It is sectional drawing in the front-back direction of the flaw detection apparatus shown in FIG. It is sectional drawing in the width direction of the flaw detection apparatus shown in FIG. It is sectional drawing in the width direction of the flaw detection apparatus shown in FIG. 1, Comprising: It is sectional drawing which shows the state by which the flaw detection apparatus is arrange | positioned on the surface of a seamless metal pipe. It is a top view which shows the state by which the detection element is attached to the support unit by the 1st attachment mechanism. It is a top view which shows the state by which the detection element is not attached to the support unit by the 1st attachment mechanism. It is a top view which shows the state by which the detection element is attached to the support unit by the 2nd attachment mechanism. It is a top view which shows the state by which the detection element is not attached to the support unit by the 2nd attachment mechanism. It is sectional drawing which shows the state which the magnet provided in the support shaft has left | separated from the surface of the seamless metal pipe. It is sectional drawing which shows the state in which the magnet provided in the support shaft is contacting the surface of a seamless metal pipe. It is sectional drawing which shows the relationship between the rotating shaft of a wheel, and the output shaft which a drive unit rotates. It is sectional drawing which shows the relationship between the transmission shaft of a ball bearing, and the worm gear provided in the transmission shaft which a drive unit rotates. It is explanatory drawing which shows the state in which the ball bearing is not in contact with the surface of the seamless metal pipe, and the wheel is in contact with the surface of the seamless metal pipe. It is explanatory drawing which shows the state in which the ball bearing is in contact with the surface of the seamless metal pipe, and the wheel is not in contact with the surface of the seamless metal pipe.

  A flaw detection apparatus according to an embodiment of the present invention includes an apparatus main body, a detection element, a first rolling mechanism, a second rolling mechanism, and a switching mechanism. The device body can be placed on the surface of the tube. The detection element is provided in the apparatus main body and detects a defect of the tube. The first rolling mechanism is provided in the apparatus main body. The first rolling mechanism includes at least one sphere. The sphere is disposed so as to be in contact with the surface of the tube. The first rolling mechanism allows the sphere to roll in the axial and circumferential direction of the tube on the surface of the tube. The second rolling mechanism is provided in the apparatus main body. The second rolling mechanism includes at least one wheel. The wheel is disposed so as to be in contact with the surface of the pipe. The second rolling mechanism allows the wheel to roll in the axial direction of the tube on the surface of the tube. The switching mechanism is provided in the apparatus main body. The switching mechanism switches the operation mode by displacing one of the first rolling mechanism and the second rolling mechanism with respect to the apparatus main body. The operation mode includes a first operation mode and a second operation mode. In the first operation mode, the apparatus main body moves on the surface of the tube based on the first rolling mechanism. In the second operation mode, the apparatus main body moves on the surface of the tube based on the second rolling mechanism.

  When the flaw detection apparatus is in the first operation mode, it can move on the surface of the tube in the axial direction and the circumferential direction of the tube. For this reason, for example, it becomes easy to detect the vicinity of the marking attached to the pipe and specify the position of the pipe defect.

  When the flaw detection apparatus is in the second operation mode, the flaw detection apparatus can move only on the surface of the tube in the axial direction of the tube. Therefore, for example, it becomes easy to specify the size of the defect.

  Therefore, in the flaw detection apparatus, an operation for identifying a defect can be easily performed.

  The tube may be made of, for example, a synthetic resin containing carbon fiber, or may be made of metal. When the pipe is a metal pipe, the metal pipe may have, for example, a seam resulting from welding or a seam resulting from welding.

  Preferably, the second rolling mechanism further includes a drive mechanism that rotates the wheel. In this case, the flaw detection apparatus can detect a defect while moving at a substantially constant speed. This facilitates the work of specifying the size of the defect.

  Preferably, the flaw detection apparatus further includes an encoder that detects rotation of the wheel. In this case, the accuracy in specifying the size of the defect, specifically, the length in the axial direction of the tube is improved.

  Preferably, the flaw detection apparatus further includes a spring. The spring presses the detection element against the surface of the tube when the apparatus main body is disposed on the surface of the tube. Even when the diameters of the tubes are different, the detection element can be stably brought into contact with the surface of the tube.

  Preferably, the detection element includes an element body and an attachment. The attachment is detachably attached to the element body. The attachment contacts the surface of the tube when the device body is disposed on the surface of the tube. Even when the diameters of the tubes are different, the detection element can be stably brought into contact with the surface of the tube by changing the attachment.

  Preferably, the flaw detection apparatus further includes a magnet and an operation mechanism. The operation mechanism displaces the magnet with respect to the apparatus main body. The operation mechanism brings the magnet into contact with the surface of the tube when the apparatus main body is disposed on the surface of the tube. If the tube is made of a magnetic material, the flaw detector can be fixed on the surface of the tube.

  Preferably, the apparatus main body includes a bottom surface. The bottom surface faces the surface of the tube when the apparatus main body is disposed on the surface of the tube. The bottom surface includes a central bottom surface and a pair of inclined bottom surfaces. The pair of inclined bottom surfaces are positioned on both sides of the central bottom surface in the circumferential direction of the tube and are inclined with respect to the central bottom surface. The first rolling mechanism includes a plurality of spheres. The second rolling mechanism includes a plurality of wheels. At least one sphere is disposed on each of the pair of inclined bottom surfaces. At least one wheel is disposed on each of the pair of inclined bottom surfaces. In this case, it is possible to stabilize the state in which the flaw detection apparatus is disposed on the surface of the tube.

  Even if the diameter of the tube is different, the sphere and the wheel can be in contact with the surface of the tube. Therefore, the flaw detector can be moved on the surface of the tube even when the tube diameters are different.

  Preferably, the apparatus main body includes a bottom surface. The bottom surface faces the surface of the tube when the apparatus main body is disposed on the surface of the tube. The sphere and the wheel are arranged on the bottom surface. The flaw detection apparatus further includes a magnet. The magnet is disposed on the bottom surface. When the apparatus main body is disposed on the surface of the tube, a gap is formed between the magnet and the tube. When the tube is made of a magnetic material, the flaw detector can be stably placed on the surface of the tube.

[Embodiment]
Hereinafter, a flaw detection apparatus 10 according to an embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and the description thereof will not be repeated. In this embodiment, a case where the pipe is a seamless steel pipe will be described as an example, but the pipe is not limited to a seamless metal pipe.

  FIG. 1 is a plan view of the flaw detection apparatus 10. FIG. 2 is a plan view showing the flaw detection apparatus 10 with the cover 26 removed. FIG. 3 is a bottom view of the flaw detector 10. FIG. 4 is a cross-sectional view of the flaw detection apparatus 10 in the front-rear direction. FIG. 5 is a cross-sectional view of the flaw detection apparatus 10 in the width direction (direction perpendicular to the front-rear direction in plan view). FIG. 6 is a cross-sectional view in the width direction of the flaw detection apparatus 10 and shows a state in which the flaw detection apparatus 10 is disposed on the surface of a small-diameter seamless metal tube. In FIG. 4, the right half shows a state in which the flaw detection device 10 is arranged on the surface of the large-diameter seamless metal tube, and the left half shows the surface on the surface of the small-diameter seamless metal tube. Shows the state of being arranged. Hereinafter, the flaw detection apparatus 10 will be described with reference to FIGS.

  As shown in FIGS. 1, 2, 3, 5, and 6, the flaw detection apparatus 10 includes an apparatus main body 12, a detection element 14, a first rolling mechanism 16, a second rolling mechanism 18, And a switching mechanism 20.

  As shown in FIGS. 1, 2, 5, and 6, the apparatus main body 12 includes a base member 22, covers 24 </ b> A and 24 </ b> B, a cover 26, covers 28 </ b> A and 28 </ b> B, and a grip portion 30.

  As shown in FIGS. 3, 5, and 6, the base member 22 includes a bottom surface 23. As shown in FIGS. 5 and 6, the bottom surface 23 faces the surface SF when the flaw detector 10 is disposed on the surface SF of the seamless metal pipe SP. The bottom surface 23 includes a central bottom surface 23A and a pair of inclined bottom surfaces 23B and 23C.

  As shown in FIG. 3, the central bottom surface 23A has a substantially constant width dimension and extends in the front-rear direction (vertical direction in FIG. 3). That is, the center bottom surface 23A extends with a substantially constant width dimension in the axial direction of the seamless metal pipe SP in a state where the flaw detection apparatus 10 is disposed on the surface SF of the seamless metal pipe SP (see FIGS. 5 and 6). ing. As is clear from this, the front-rear direction of the flaw detection apparatus 10 coincides with the axial direction of the seamless metal pipe SP.

  As shown in FIGS. 5 and 6, the pair of inclined bottom surfaces 23 </ b> B and 23 </ b> C are located on both sides of the central bottom surface 23 </ b> A in the circumferential direction of the seamless metal pipe SP. Each inclined bottom surface 23B, 23C is inclined with respect to the central bottom surface 23A. As shown in FIG. 3, each inclined bottom surface 23B, 23C has a substantially constant width dimension and extends in the front-rear direction (vertical direction in FIG. 3).

  As shown in FIG. 4, the base member 22 has two recesses 22 </ b> A and 22 </ b> B. The two recesses 22A are separated in the front-rear direction (left-right direction in FIG. 4).

  As shown in FIG. 4, a drive unit 32A is disposed in the recess 22A. A drive unit 32B is disposed in the recess 22B. Each drive unit 32A, 32B includes, for example, an electric motor and a speed reduction means. The reduction means is, for example, a reduction gear train.

  As shown in FIG. 2, each drive unit 32A, 32B includes two output shafts 34A, 34B. An output gear 36A is disposed on the output shaft 34A. An output gear 36B is disposed on the output shaft 34B.

  As shown in FIGS. 2 and 4, the cover 24A covers the drive unit 32A. The cover 24B covers the drive unit 32B.

  As shown in FIGS. 2 and 4 to 6, a support unit 38 is disposed on the base member 22. That is, the apparatus main body 12 includes the support unit 38. The support unit 38 is movable in the vertical direction (the vertical direction in FIGS. 4 to 6) with respect to the base member 22.

  As shown in FIGS. 2 and 4, the support unit 38 includes a main body 38A and a convex portion 38B. The convex portion 38B protrudes downward from the lower surface of the main body 38A. As shown in FIGS. 2 and 3, the cross-sectional shape of the convex portion 38 </ b> B (the cross-sectional shape in the direction perpendicular to the protruding direction) is slightly smaller than the opening shape of the hole 40 formed in the base member 22. As the convex portion 38B moves in the hole 40, the support unit 38 moves in the vertical direction with respect to the base member 22 (see FIGS. 4 to 6).

  As shown in FIGS. 3 and 4, the support unit 38 includes two ball bearings 42A and 42B. The two ball bearings 42A and 42B are disposed at the tip of the convex portion 38B. The two ball bearings 42A and 42B are arranged at the same position in the protruding direction of the convex portion 38B. The two ball bearings 42A and 42B are separated in the front-rear direction.

  As shown in FIGS. 3 and 4, each ball bearing 42 </ b> A, 42 </ b> B includes a sphere 44 and a housing 46. The housing 46 rotatably supports the sphere 44.

  As shown in FIGS. 2 to 6, the detection element 14 is arranged in the support unit 38. That is, the detection element 14 is provided in the apparatus main body 12. If the detection element 14 can detect the defect of the seamless metal pipe SP in a state where the flaw detection apparatus 10 is disposed on the surface SF of the seamless metal pipe SP (see FIGS. 5 and 6), It is not limited. The detection element 14 may be, for example, an ultrasonic probe or an eddy current sensor array. Incidentally, in the present embodiment, the detection element 14 is an ultrasonic probe.

  As shown in FIGS. 2 to 6, the detection element 14 includes an element body 14 </ b> A and an attachment 14 </ b> B.

  As shown in FIG. 4, one end of a cord 15 is connected to the element body 14A. The other end of the cord 15 is connected to a measuring device provided separately from the flaw detection device 10. The signal detected by the element body 14A is sent to the measuring device via the code 15. The measuring device includes a display unit. The measuring device processes the signal sent from the element main body 14A and displays the result on the display unit.

  The attachment 14B is a so-called wedge. The attachment 14B is detachably provided on the element body 14A. As shown in FIGS. 5 and 6, the attachment 14 </ b> B is in contact with the surface SF of the seamless metal pipe SP when the flaw detection apparatus 10 is disposed on the surface SF of the seamless metal pipe SP.

  As shown in FIGS. 3 and 4, the detection element 14 is disposed between the two ball bearings 42 </ b> A and 42 </ b> B. The detection element 14 is disposed in a hole 48 formed in the support unit 38. In this state, the detection element 14 is attached to the support unit 38 by a pair of attachment mechanisms 50 and 50 and a pair of attachment mechanisms 52 and 52 as shown in FIGS.

  The pair of attachment mechanisms 50 and 50 and the pair of attachment mechanisms 52 and 52 will be described with reference to FIGS. 4 and 7 to 10. FIG. 7 is a plan view showing a state in which the detection element 14 is attached to the support unit 38 by the pair of attachment mechanisms 50, 50. FIG. 8 is a plan view showing a state in which the detection element 14 is not attached to the support unit 38 by the pair of attachment mechanisms 50, 50. FIG. 9 is a plan view showing a state in which the detection element 14 is attached to the support unit 38 by the pair of attachment mechanisms 52, 52. FIG. 10 is a plan view showing a state in which the detection element 14 is not attached to the support unit 38 by the pair of attachment mechanisms 52, 52.

  As shown in FIGS. 2, 7, and 8, each of the pair of attachment mechanisms 50, 50 includes a rotating body 50A, an attachment member 50B, and a screw 50C.

  The rotating body 50A is disposed on the upper surface of the support unit 38. The rotating body 50A is rotatable around the central axis of the support pin 54. A part of the outer peripheral surface of the rotating body 50 </ b> A is a plane parallel to the central axis of the support pin 54.

  The attachment member 50 </ b> B includes a cylinder 56 and a shaft 58. The shaft 58 protrudes from the outer peripheral surface of the cylinder 56. The shaft 58 is inserted into one of the two holes 60 </ b> A and 60 </ b> B that open on the upper surface of the support unit 38.

  The screw 50C is inserted into the cylinder 56 and attached to the rotating body 50A.

  As shown in FIGS. 4, 9, and 10, each of the pair of attachment mechanisms 52, 52 includes a holding member 62 and two screws 64.

  The holding member 62 is disposed at the tip of the convex portion 38B. The holding member 62 can slide in the front-rear direction. Two holes 62 </ b> A (see FIG. 4) are formed in the holding member 62. Each hole 62A is a long hole extending in the front-rear direction. A screw 64 is inserted into each hole 62A. The screw 64 is attached to the convex portion 38.

  The detection element 14 is attached to the support unit 38 by a pair of attachment mechanisms 50 and 50 and a pair of attachment mechanisms 52 and 52 as follows.

  First, the detection element 14 is disposed in the hole 40. At this time, the detection element 14 (specifically, the attachment 14B) is positioned between the pair of holding members 62 and 62. Each holding member 62 is moved toward the detection element 14, and the detection element 14 is sandwiched between the pair of holding members 62 and 62 as shown in FIG. In this state, the screw 64 is tightened. At this time, the step 141 formed on the attachment 14 </ b> B contacts each holding member 62. Thereby, it is possible to prevent the detection element 14 from coming out of the hole 40 (specifically, coming out below the support unit 38).

  Subsequently, the rotating body 50A is rotated around the support pin 54, and a part of the rotating body 50A is detected by the detection element 14 (specifically, the element main body 14A) when viewed from the opening direction of the hole 40, that is, from the vertical direction. ). Subsequently, the shaft 58 of the attachment member 50B is inserted into the hole 60A. Subsequently, the screw 50C is inserted into the cylinder 56 of the attachment member 50B, and the screw 50C is attached to the rotating body 50A. Accordingly, as shown in FIG. 7, the pair of attachment mechanisms 50, 50 can prevent the detection element 14 from coming out of the hole 40 (specifically, coming out above the support unit 38).

  As described above, the detection element 14 is prevented from coming out of the hole 40. As a result, the detection element 14 is attached to the support unit 38.

  The detection element 14 can be removed from the support unit 38 as follows.

  First, the screw 50C is removed from the rotating body 50A and extracted from the tube 56 of the mounting member 50B. Subsequently, the rotating body 50A is rotated around the support pin 54 so that the rotating body 50A overlaps the detection element 14 (specifically, the element main body 14A) when viewed from the direction in which the hole 40 opens, that is, the vertical direction. Do not become. Thereby, the detection element 14 can be extracted from the hole 40. When the rotating body 50A is in the above position, after the shaft 58 of the mounting member 50B is inserted into the hole 60B, the screw 50C is inserted into the tube 56 of the mounting member 50B, and the screw 50C is attached to the rotating body 50A. Also good. In this case, as shown in FIG. 8, the rotating body 50A can be fixed at the above position.

  Alternatively, the screw 64 is loosened and each holding member 62 is moved away from the detection element 14 as shown in FIG. Thereby, the detection element 14 can be extracted from the hole 40.

  As shown in FIGS. 2 and 4, the support unit 38 includes two support shafts 66. The two support shafts 66 are separated in the front-rear direction. One end of the support shaft 66 is located in a recess 68 formed in the support unit 38. The other end of the support shaft 66 is inserted into a hole 70 formed in the base member 22. The support shaft 66 can move in the vertical direction by the guide action of the recess 68 and the hole 70. An operation lever 72 is provided on the support shaft 66. A magnet 74 is attached to the other end of the support shaft 66.

  A case where the support shaft 66 is moved up and down will be described with reference to FIGS. 11A and 11B. FIG. 11A is a cross-sectional view showing a state where the magnet 74 provided on the support shaft 66 is separated from the surface SF of the seamless metal pipe SP. FIG. 11B is a cross-sectional view showing a state where the magnet 74 provided on the support shaft 66 is in contact with the surface SF of the seamless metal pipe SP.

  The support shaft 66 is moved in the vertical direction by rotating the operation lever 72. In a state where the flaw detection apparatus 10 is disposed on the surface SF of the seamless metal pipe SP, the operation lever 72 is rotated. As shown in FIG. 11A, when the magnet 74 is away from the surface SF, the magnet 74 comes into contact with the surface SF as shown in FIG. 11B by rotating the operation lever 72. When the seamless metal pipe SP is made of a magnetic material, the flaw detector 10 can be fixed on the seamless metal pipe SP by the action of the magnetic force of the magnet 74. On the other hand, as shown in FIG. 11B, when the magnet 74 is in contact with the surface SF, by rotating the operation lever 72, the magnet 74 is separated from the surface SF as shown in FIG. 11A. Thereby, the fixed state to the seamless metal pipe SP of the flaw detector 10 using the action of the magnetic force of the magnet 74 can be released. That is, in this embodiment, the operation mechanism is realized including the operation lever 72 and the support shaft 66.

  As shown in FIGS. 1 and 4 to 6, a cover 26 is disposed on the base member 22. The cover 26 covers the support unit 38.

  As shown in FIGS. 1 and 4 to 6, a grip portion 30 is disposed on the cover 26. The operator moves the flaw detection apparatus 10 on the surface SF of the seamless metal pipe SP while holding the grip portion 30.

  As shown in FIG. 4, the grip portion 30 has a recess 30 </ b> A. A cutout 26 </ b> A is formed in the side wall of the cover 26. An opening 26 </ b> B is formed in the top plate of the cover 26. The cord 15 connected to the detection element 14 extends to the outside of the flaw detection apparatus 10 through the recess 30A, the opening 26B, and the notch 26A.

  As shown in FIGS. 2, 3, 5, and 6, the flaw detection apparatus 10 further includes two coil springs 102. One end of the coil spring 102 is located in a hole 104 formed in the base member 22. One end of the coil spring 102 is fixed to the base member 22. The other end of the coil spring 102 is located in a cylinder 106 provided in the support unit 38. The other end of the coil spring 102 is fixed to the cylinder 106. One end of the tube 106 (the end to which the coil spring 102 is fixed) is located in the recess 30 </ b> B formed in the grip portion 30.

  The urging force of the coil spring 102 is constantly applied to the support unit 38 in the direction in which the support unit 38 is brought closer to the base member 22. As a result, as shown in FIGS. 5 and 6, even when the flaw detection apparatus 10 is disposed on the surface SF of the seamless metal pipe SP having different diameters, the detection element 14 contacts the surface SF. .

  As shown in FIGS. 2, 3, 5, and 6, the flaw detection apparatus 10 further includes two rods 108. The rod 108 is inserted into a cylinder 110 provided in the support unit 38. One end of the rod 108 is fixed to the base member 22. The other end of the rod 108 is fixed to the grip portion 30.

  As shown in FIGS. 2 and 3, the first rolling mechanism 16 is disposed on the base member 22. The first rolling mechanism 16 includes a plurality (eight in the present embodiment) of ball bearings 16A to 16H.

  Of the eight ball bearings 16A to 16H, the four ball bearings 16A to 16D are disposed on the inclined bottom surface 23B. These ball bearings 16A to 16D are arranged in the front-rear direction. The two ball bearings 16A and 16B are located in front of the detection element 14. The two ball bearings 16 </ b> C and 16 </ b> D are located behind the detection element 14.

  Of the eight ball bearings 16A to 16H, the four ball bearings 16E to 16H are disposed on the inclined bottom surface 23C. These ball bearings 16E to 16H are arranged in the front-rear direction. The two ball bearings 16E and 16F are located in front of the detection element 14. The two ball bearings 16G and 16H are located behind the detection element 14.

  Each of the ball bearings 16 </ b> A to 16 </ b> H includes a sphere 76, a housing 78, and a transmission shaft 80. The housing 78 supports the sphere 76 in a rotatable manner. The transmission shaft 80 is provided in the housing 78.

  As shown in FIG. 3, a plurality (eight in this embodiment) of magnets 17 </ b> A to 17 </ b> H are arranged on the bottom surface 23 of the base member 22.

  Of the eight magnets 17A to 17H, the four magnets 17A to 17D are disposed on the inclined bottom surface 23B. The magnet 17A is located between the ball bearing 16A and the ball bearing 16B. The magnet 17B and the magnet 17C are located between the ball bearing 16B and the ball bearing 16C. Magnet 17D is located between ball bearing 16C and ball bearing 16D.

  As shown in FIG. 4, the end surfaces of the four magnets 17A to 17D are at the same position as the inclined bottom surface 23B in the direction perpendicular to the inclined bottom surface 23B. That is, the four magnets 17A to 17D are separated from the surface SF in a state where the flaw detection apparatus 10 is disposed on the surface SF of the seamless metal pipe SP (see FIGS. 5 and 6).

  As shown in FIG. 3, among the eight magnets 17A to 17H, the four magnets 17E to 17H are arranged on the inclined bottom surface 23C. The magnet 17E is located between the ball bearing 16E and the ball bearing 16F. Magnet 17F and magnet 17G are located between ball bearing 16F and ball bearing 16G. The magnet 17H is located between the ball bearing 16G and the ball bearing 16H.

  The end surfaces of the four magnets 17E to 17H are at the same position as the inclined bottom surface 23C in the direction perpendicular to the inclined bottom surface 23C, as in the case of the four magnets 17A to 17D. That is, the four magnets 17E to 17H are separated from the surface SF in a state where the flaw detection apparatus 10 is disposed on the surface SF of the seamless metal pipe SP (see FIGS. 5 and 6).

  As shown in FIG. 2, the second rolling mechanism 18 is disposed on the base member 22. The second rolling mechanism 18 includes a plurality of (four in this embodiment) wheels 18A to 18D. Wheel 18A-18D is arrange | positioned in the recessed part formed in the base member 22, for example. The concave portion is covered with, for example, covers 28A and 28B.

  As shown in FIG. 3, the wheel 18A is located in an opening 25A formed in the inclined bottom surface 23B. As shown in FIG. 2, the wheel 18A is disposed near the output shaft 34A provided in the drive unit 32A. The wheel 18A includes a rotating shaft 96A. The rotation of the output shaft 34A included in the drive unit 32A is transmitted to the rotation shaft 96A, whereby the wheel 18A rotates.

  As shown in FIG. 3, the wheel 18B is located in an opening 25B formed in the inclined bottom surface 23B. As shown in FIG. 2, the wheel 18B is disposed near the output shaft 34A provided in the drive unit 32B. The wheel 18B includes a rotation shaft 96B. When the rotation of the output shaft 34A included in the drive unit 32B is transmitted to the rotation shaft 96B, the wheel 18B rotates.

  As shown in FIG. 3, the wheel 18C is located in an opening 25C formed in the inclined bottom surface 23C. As shown in FIG. 2, the wheel 18C is disposed near the output shaft 34B provided in the drive unit 32A. The wheel 18C includes a rotation shaft 96C. The rotation of the output shaft 34B included in the drive unit 32A is transmitted to the rotation shaft 96C, whereby the wheel 18C rotates.

  As shown in FIG. 3, the wheel 18D is located in an opening 25D formed in the inclined bottom surface 23C. As shown in FIG. 2, the wheel 18D is disposed near the output shaft 34B included in the drive unit 32B. The wheel 18D includes a rotation shaft 96D. When the rotation of the output shaft 34B included in the drive unit 32B is transmitted to the rotation shaft 96D, the wheel 18D rotates.

  The relationship between the output shaft 34A and the rotation shaft 96A provided in the drive unit 32A will be described with reference to FIG. FIG. 12 is a cross-sectional view showing the relationship between the output shaft 34A and the rotation shaft 96A provided in the drive unit 32A. The relationship between the output shaft 34B and the rotation shaft 96B included in the drive unit 32A, the relationship between the output shaft 34A and the rotation shaft 96C included in the drive unit 32B, and the relationship between the output shaft 34B and the rotation shaft 96D included in the drive unit 32B. The relationship is the same as that shown in FIG.

  The output gear 36A included in the output shaft 34A of the drive unit 32A meshes with the gear 98A included in the rotating shaft 96A. Therefore, when the output shaft 34A included in the drive unit 32A rotates, the rotation shaft 96A rotates. As a result, the wheel 18A rotates.

  As is clear from the above description, in this embodiment, the drive mechanism is realized including the drive units 32A and 32B and the rotation shafts 96A to 96D. The operation of the drive units 32A and 32B is controlled by a switch 112 (see FIG. 1) provided in the grip portion 30.

  As shown in FIG. 2, an encoder 100A is arranged near the output shaft 34A provided in the drive unit 32A. The encoder 100A is coupled to the output shaft 34A included in the drive unit 32A in order to detect the rotation of the output shaft 34A included in the drive unit 32A.

  As shown in FIG. 2, an encoder 100B is disposed near the output shaft 34A provided in the drive unit 32B. The encoder 100B is coupled to the output shaft 34A included in the drive unit 32B in order to detect the rotation of the output shaft 34A included in the drive unit 32B.

  As shown in FIG. 2, a transmission shaft 82A and a drive unit 84A are arranged near the four ball bearings 16A to 16D. The drive unit 84A includes, for example, an electric motor and a speed reduction unit. The reduction means is, for example, a reduction gear train. The drive unit 84A rotates the transmission shaft 82A. The transmission shaft 82A extends in the front-rear direction. The transmission shaft 82A includes four worm gears 83A to 83D. The four worm gears 83A to 83D are arranged away from each other in the front-rear direction. The transmission shaft 82A and the drive unit 84A are disposed in a recess formed in the base member 22, for example. The concave portion is covered with, for example, a cover 28A.

  The relationship between the four worm gears 83A to 83D included in the transmission shaft 82A and the transmission shaft 80 included in each of the four ball bearings 16A to 16D will be described with reference to FIGS. FIG. 13 is a cross-sectional view showing the relationship between the transmission shaft 80 and the worm gear 83A of the ball bearing 16A. The relationship between the transmission shaft 80 and the worm gear 83B included in the ball bearing 16B, the relationship between the transmission shaft 80 and the worm gear 83C included in the ball bearing 16C, and the relationship between the transmission shaft 80 and the worm gear 83D included in the ball bearing 16D. The relationship is also the same as that shown in FIG.

  As shown in FIG. 13, the transmission shaft 80 includes a shaft 80A and a gear 80B. The shaft 80 </ b> A is provided in the housing 78. The shaft 80A protrudes from the end surface of the housing 78 opposite to the end surface from which the sphere 76 is exposed. The gear 80B is attached to the shaft 80A. The gear 80B rotates integrally with the shaft 80A. The housing 78 is disposed in the recess 86. The shaft 80A is inserted into the hole 88. A part of the shaft 80 </ b> A is located in the recess 90. The recess 90 is connected to the recess 86 via the hole 88. The gear 80 </ b> B is located in the recess 90. The distal end of the shaft 80A is rotatably supported by a support member 92. The support member 92 is attached to the base member 22. The recess 90 is covered by the cover 28A.

  As shown in FIG. 13, the worm gear 83A meshes with the gear 80B of the ball bearing 16A. As the worm gear 83A rotates, the gear 80B rotates. As the gear 80B rotates, the ball bearing 16A moves in the axial direction of the transmission shaft 80. That is, when the worm gear 83 </ b> A rotates, the transmission shaft 80 rotates and the ball bearing 16 </ b> A moves in the axial direction of the transmission shaft 80.

  Similarly, the rotation of the worm gear 83B is transmitted to the transmission shaft 80 of the ball bearing 16B. As a result, the ball bearing 16B moves in the axial direction of the transmission shaft 80.

  Similarly, the rotation of the worm gear 83C is transmitted to the transmission shaft 80 of the ball bearing 16C. As a result, the ball bearing 16C moves in the axial direction of the transmission shaft 80.

  Similarly, the rotation of the worm gear 83D is transmitted to the transmission shaft 80 of the ball bearing 16D. As a result, the ball bearing 16D moves in the axial direction of the transmission shaft 80.

  The four worm gears 83A to 83D are provided on the transmission shaft 82A. Therefore, the rotations of the four worm gears 83A to 83D are synchronized. Accordingly, the movements of the four ball bearings 16A to 16D are also synchronized.

  As shown in FIG. 2, a transmission shaft 82B and a drive unit 84B are arranged near the four ball bearings 16E to 16H. The drive unit 84B includes, for example, an electric motor and a speed reduction unit. The reduction means is, for example, a reduction gear train. The drive unit 84B rotates the transmission shaft 82B. The transmission shaft 82B extends in the front-rear direction. Four worm gears 83E to 83H are arranged on the transmission shaft 82B. The transmission shaft 82 </ b> B and the drive unit 84 </ b> B are disposed in a recess formed in the base member 22, for example. The concave portion is covered with, for example, a cover 28B.

  Here, the relationship between the four worm gears 83E to 83H that the transmission shaft 82B has and the transmission shaft 80 that each of the four ball bearings 16E to 16H has is the four worm gears 83A to 83D that the transmission shaft 82A has, The relationship with the transmission shaft 80 of each of the four ball bearings 16A to 16D is the same. That is, the rotation of the worm gear 83E is transmitted to the transmission shaft 80 of the ball bearing 16E. As a result, the ball bearing 16E moves in the axial direction of the transmission shaft 80.

  Similarly, the rotation of the worm gear 83F is transmitted to the transmission shaft 80 of the ball bearing 16F. As a result, the ball bearing 16F moves in the axial direction of the transmission shaft 80.

  Similarly, the rotation of the worm gear 83G is transmitted to the transmission shaft 80 of the ball bearing 16G. As a result, the ball bearing 16G moves in the axial direction of the transmission shaft 80.

  Similarly, the rotation of the worm gear 83H is transmitted to the transmission shaft 80 of the ball bearing 16H. As a result, the ball bearing 16H moves in the axial direction of the transmission shaft 80.

  The four worm gears 83E to 83H are provided on the transmission shaft 82B. Therefore, the rotations of the four worm gears 83E to 83H are synchronized. Accordingly, the movements of the four ball bearings 16E to 16H are also synchronized.

  As described above, the ball bearings 16A to 16H move. On the other hand, the wheels 18A to 18D do not move. That is, the ball bearings 16A to 16H move with respect to the wheels 18A to 18D.

  With reference to FIG. 14A and FIG. 14B, the relationship between the ball bearing 16A and the wheel 18A and the surface SF in a state where the flaw detection apparatus 10 is disposed on the surface SF of the seamless metal pipe SP will be described. FIG. 14A is an explanatory diagram showing a state in which the ball bearing 16A is not in contact with the surface SF and the wheel 18A is in contact with the surface SF. FIG. 14B is an explanatory diagram illustrating a state in which the ball bearing 16A is in contact with the surface SF and the wheel 18A is not in contact with the surface SF. 14A and 14B show the ball bearing 16A and the wheel 18A and the surface SF as an example, but the relationship between the other ball bearing and wheel and the surface SF is also shown in FIGS. 14A and 14B. The same.

  The ball bearing 16A is moved in a direction protruding from the inclined bottom surface 23B, that is, in a direction of exiting from the recess 86 (see FIG. 13). In this case, as shown in FIG. 14A, the sphere 76 included in the ball bearing 16A is in contact with the surface SF. On the other hand, wheel 18A is separated from surface SF. That is, the first operation mode in which the spheres 76 of the ball bearings 16A to 16H roll on the surface SF is realized.

  The ball bearing 16A is moved in a direction that does not protrude from the inclined bottom surface 23B, that is, in a direction in which it is accommodated in the recess 86 (see FIG. 13). In this case, as shown in FIG. 14B, the sphere 76 included in the ball bearing 16A is separated from the surface SF. On the other hand, wheel 18A is in contact with surface SF. That is, the second operation mode in which the wheels 18A to 18D roll on the surface SF is realized.

  As described above, in order to move the ball bearings 16A to 16D, the transmission shaft 82A is rotated by the drive unit 84A, and the rotation of the transmission shaft 82A is transmitted to the transmission shaft 80 of the ball bearings 16A to 16D. In order to move the ball bearings 16E to 16H, the transmission shaft 82B is rotated by the drive unit 84B, and the rotation of the transmission shaft 82B is transmitted to the transmission shaft 80 of the ball bearings 16E to 16H. That is, in this embodiment, the switching mechanism 20 is realized including the drive units 84A and 84B, the transmission shafts 82A and 82B, and the transmission shafts 80 of the ball bearings 16A to 16H. The operations of the drive units 84A and 84B are controlled by a switch 114 (see FIG. 1) provided in the grip portion 30.

  Subsequently, a flaw detection method using the flaw detection apparatus 10 will be described. It is a defect of the seamless metal pipe SP that is subject to flaw detection. Specifically, lamination.

  First, a seamless metal pipe SP in which markings are provided at approximate positions of defects is prepared. The marking is given, for example, when a defect of the seamless metal pipe SP moving on the transport line is detected by an ultrasonic flaw detector.

  Subsequently, the flaw detection apparatus 10 detects the vicinity of the marking attached to the seamless metal pipe SP, and specifies the position where the defect is formed and the size (area) of the defect. Specifically, it is as follows.

  First, the flaw detection apparatus 10 is disposed on the surface SF of the seamless metal pipe SP. Subsequently, the switch 114 is operated to move each of the ball bearings 16A to 16H. Thereby, each sphere 76 of ball bearings 16A-16H contacts surface SF, and wheels 18A-18D separate from surface SF (refer to Drawing 14A). That is, the first operation mode in which the sphere 76 rolls on the surface SF is realized. In this case, the flaw detection apparatus 10 can move in the axial direction and the circumferential direction of the seamless metal pipe SP.

  In a state where the flaw detection apparatus 10 is disposed on the surface SF, the detection element 14 (specifically, the attachment 14B) is in contact with the surface SF, and the spheres 44 of the ball bearings 42A and 42B are in contact with the surface SF. (See FIG. 4). That is, the sphere 44 rolls on the surface SF.

  The detection element 14 and the ball bearings 42A and 42B are pressed against the surface SF by the biasing force of the coil spring 102. Therefore, even when the size (specifically, the diameter) of the seamless metal pipe SP is different, the detection element 14 and the ball bearings 42A and 42B are stably brought into contact with the surface SF of the seamless metal pipe SP. Can do.

  As described above, in the state where the first operation mode is set, the flaw detection apparatus 10 can move in the axial direction and the circumferential direction of the seamless metal pipe SP. Therefore, it is easy to detect the vicinity of the marking and specify the specific position of the defect.

  After the specific position of the defect is specified by the flaw detection apparatus 10, the switch 114 is operated to move each of the ball bearings 16A to 16H. Thereby, each sphere 76 of ball bearings 16A-16H does not contact surface SF, and wheels 18A-18D contact surface SF (refer to Drawing 14B). That is, the second operation mode in which the wheels 18A to 18D roll on the surface SF is realized. In this case, the flaw detection apparatus 10 can move only in the axial direction of the seamless metal pipe SP.

  Subsequently, the switch 112 is operated to drive the drive units 32A and 32B. Thereby, output shaft 34A, 34B with which each drive unit 32A, 32B is provided rotates. As a result, the rotation shafts 96A to 96D rotate. That is, the wheels 18A to 18D rotate. As a result, the flaw detection apparatus 10 moves on the surface SF of the seamless metal pipe SP at a substantially constant speed in the axial direction of the seamless metal pipe SP. At this time, the detection element 14 detects a defect. Therefore, it becomes easy to specify the specific size of the defect, that is, the area.

  The flaw detection apparatus 10 includes encoders 100A and 100B. Therefore, the accuracy in specifying the size of the defect, specifically, the length of the seamless metal pipe SP in the axial direction is improved.

  The detection element 14 includes an attachment 14B. Therefore, even if the size (specifically, the diameter) of the seamless metal pipe SP is different, the attachment element 14B is changed so that the detection element 14 is stably brought into contact with the surface SF of the seamless metal pipe SP. Can be made.

  The flaw detection apparatus 10 includes a magnet 74. The operation lever 72 can be rotated to bring the magnet 74 into contact with the surface SF of the seamless metal pipe SP. When the seamless metal pipe SP is made of a magnetic material, the flaw detector 10 can be fixed on the surface SF of the seamless metal pipe SP.

  In the flaw detection apparatus 10, four ball bearings 16A to 16D and two wheels 18A and 18C are disposed on the inclined bottom surface 23B, and four ball bearings 16E to 16H and two wheels 18B and 18D are disposed. Therefore, the state in which the flaw detection apparatus 10 is disposed on the surface SF of the seamless metal pipe SP can be stabilized.

  Even when the sizes (specifically, the diameters) of the seamless metal pipe SP are different, the spheres 76 and the wheels 18A to 18D of the ball bearings 16A to 16H may be brought into contact with the surface SF of the seamless metal pipe SP. it can. Even when the sizes (specifically, diameters) of the seamless metal pipe SP are different, the flaw detection apparatus 10 can be moved on the surface SF of the seamless metal pipe SP.

  The flaw detection apparatus 10 includes magnets 17A to 17H. When the seamless metal pipe SP is made of a magnetic material, the flaw detector 10 can be stably disposed on the surface SF of the seamless metal pipe SP.

  As mentioned above, although embodiment of this invention has been explained in full detail, this is an illustration to the last, Comprising: This invention is not limited at all by the above-mentioned embodiment.

10: flaw detection device, 12: device main body, 14: detection element, 16: first rolling mechanism, 18: second rolling mechanism, 20: switching mechanism

Claims (1)

A device body that can be placed on the surface of the tube;
A detection element provided in the apparatus body for detecting a defect in the tube;
A first rolling mechanism provided in the apparatus body;
A second rolling mechanism provided in the apparatus body;
In the flaw detection apparatus , comprising a switching mechanism provided in the apparatus body ,
The first rolling mechanism includes at least one sphere disposed in contact with the surface of the tube,
The second rolling mechanism includes at least one wheel arranged to be in contact with the surface of the pipe,
The switching mechanism displaces one of the first rolling mechanism and the second rolling mechanism with respect to the apparatus main body, so that the sphere rolls on the surface of the tube so that the apparatus main body becomes the first rolling mechanism. A first operation mode that moves on the surface of the tube based on one rolling mechanism; and the apparatus body moves on the surface of the tube based on the second rolling mechanism by the wheels rolling on the surface of the tube. To switch to the second operation mode to move up,
In the first operation mode, the sphere of the first rolling mechanism is in contact with the surface of the tube, and the wheel of the second rolling mechanism is separated from the surface of the tube,
In the second operation mode, the flaw detection apparatus, wherein the wheel of the second rolling mechanism is in contact with the surface of the tube, and the sphere of the first rolling mechanism is separated from the surface of the tube .

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