JP2004144710A - Wall thickness measuring system of large diameter pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wall thickness measuring system of a large diameter pipe wherein no laying out of a scaffold is required for measurement, and a corrosion on the outside surface is accurately and efficiently understood, with no burden on a worker. <P>SOLUTION: A master truck 14 comprises running wheels 11a-11d having driven tires of soft material and travels on an inside surface 13 of a large diameter pipe 12. Magnets 15 and 16 are fixed to the bottom part of the truck 14 and have such magnetic force as can fix the truck 14 to an arbitrary position on the inner surface of the large diameter pipe 12. Four or more slave trucks 17-22 are arranged in two lines and in zigzag in the advancing direction of the master truck 14, being so provided to the master truck 14 for vertical movement and swinging back and forth while energized to the large diameter pipe 12 at always, with four small wheels 69-69d provided looking in the same direction as the master truck 14. A range finder 26 measures a travel distance of the master truck 14. A multi-channel type ultrasonic controller 24 actuates an ultrasonic sensor 23 at the same time. A display device 118 displays a measuring result of wall thickness. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is used, for example, for cooling condensers used in power plants and the like, and measures the thickness of a large-diameter pipe thickness measuring system for measuring the external corrosion of a large-diameter circulating water pipe buried in the ground or in concrete. About.
[0002]
[Prior art]
Conventionally, for example, most of large-diameter pipes such as large-diameter circulating water pipes used for cooling condensers used in nuclear power plants and hydroelectric power plants are buried underground or under concrete. Due to long-term use of up to 20 years, there is a concern about corrosion occurring on the outer surface of the pipe due to moisture or the like. Therefore, in consideration of safe operation and extension of the service life, it is necessary to identify the site of occurrence of external corrosion and to confirm the existence and progress of extensive corrosion. Since it is not practical to dig a pipe, a spot-like measurement using an ultrasonic thickness gauge is performed manually from the inside of the pipe as a method for examining corrosion on the outside, but a scaffold for measurement is installed inside the pipe. It requires erection and the like, which requires a large amount of construction cost and construction period, and it is difficult to accurately grasp the external corrosion state because of the spot measurement. Further, since the measurement is performed manually, it is a severe work for the operator who performs the measurement.
In order to solve such a problem, a slide unit for reciprocating a moving body in a running direction is mounted on a bogie having magnet wheels and capable of running in a pipe axis direction and a circumferential direction. 2. Description of the Related Art There is known a plate thickness measuring device that is provided with an elevating cylinder that presses an acoustic wave sensor onto a measurement surface and thereby automatically measures the plate thickness at a predetermined measurement position such as a pipe (for example, see Patent Document 1).
[0003]
[Patent Document 1]
JP-A-10-232125 (abstract, FIGS. 1 to 4)
[0004]
[Problems to be solved by the invention]
However, the plate thickness measuring device of Patent Document 1 has the following problems to be solved.
The magnet wheel that rolls on the measurement surface is made of metal and has a strong attraction force, so that there is a problem that the coating layer of the pipe is damaged and the corrosion of the pipe is accelerated.
The bogie can travel in the pipe axis direction and circumferential direction, but with the bogie stopped, one ultrasonic sensor is moved to the measurement position, and then the ultrasonic sensor is pressed against the measurement surface. When measuring the entire pipe (in the pipe axis direction and the circumferential direction) to check the state of corrosion, there is a problem that the work efficiency of the measurement is extremely poor.
[0005]
The present invention has been made in view of such circumstances, and it is not necessary to provide a scaffold for measurement, and the like, and it is possible to accurately and efficiently grasp the external corrosion state, thereby not burdening the operator. An object of the present invention is to provide a system for measuring the thickness of a large-diameter pipe.
[0006]
[Means for Solving the Problems]
A thickness measuring system for a large-diameter pipe according to the present invention that meets the above-mentioned object has a tire having four running wheels, each of which is driven by a soft material, and a parent bogie capable of running on the inner surface of the large-diameter pipe, A magnet fixed to the bottom of the main bogie and having a magnetic force capable of fixing the main bogie to an arbitrary position on the inner surface of the large-diameter pipe with a small gap from the inner surface of the large-diameter pipe, and two rows in the traveling direction of the main bogie. And it is arranged in a staggered manner, and is provided on the parent bogie so that it can move up and down and swing back and forth, and is always urged to the large-diameter pipe, each of which has four small wheels facing the same direction as the parent bogie. Simultaneously operate four or more sub-carts and a reflection-type ultrasonic sensor provided on each sub-cart and having a small gap between the inner surface of the large-diameter tube and the ultrasonic sensor. Multi-channel type ultrasonic controller, ultrasonic sensor and large diameter tube Water supply means for supplying medium water to the gap formed between the ultrasonic sensor and the parent bogie is provided at a different position, a distance meter for measuring the travel distance of the parent bogie, the output of the distance meter and A display device that receives the output of the multi-channel ultrasonic controller as an input, wherein the child carriages are arranged beyond the interference area of the ultrasonic sensors mounted on the adjacent child carriages, and The trolley is placed in a range of more than 1 time and less than 2 times the effective width of the ultrasonic sensor in the lateral direction, and the display device measures the inner diameter of the large-diameter tube from the output of the distance meter and the output of the ultrasonic sensor. A thickness distribution having a predetermined width with respect to the position is output.
[0007]
This eliminates the need for installation of a scaffold for measurement, etc., and allows the child cart equipped with an ultrasonic sensor to move up and down and swing back and forth on the parent cart equipped with a magnet to run on the inner surface of the large diameter pipe. Moreover, by outputting a thickness distribution of a predetermined width with respect to the measurement position in the inner circumferential direction of the large-diameter tube to the display device from the output of the distance meter and the output of the ultrasonic sensor, the thickness of the entire large-diameter tube is substantially reduced. It can be measured automatically and continuously.
[0008]
In the system for measuring the thickness of a large-diameter pipe according to the present invention, the magnets may be provided before and after the parent carriage. Thereby, when the parent vehicle travels in the inner circumferential direction of the large-diameter pipe having the concave curved surface, the parent vehicle can travel stably.
In the system for measuring the thickness of a large-diameter pipe according to the present invention, four traveling wheels are independently driven by a reduction motor, and the reduction motor may be provided with a worm reduction gear or a reduction gear with a brake. Accordingly, the four running wheels are independently driven, so that the parent bogie can travel to an arbitrary position, and since the worm speed reducer or the speed reducer with a brake is provided, the positioning of the main bogie can be facilitated. .
[0009]
In the system for measuring the thickness of a large-diameter pipe according to the present invention, the output of the display device may be described in different colors on a plane in which the inner circumference of the large-diameter pipe is displayed in a developed state. As a result, the external corrosion state can be grasped more easily, thereby reducing the burden on the operator.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, embodiments of the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention.
Here, FIG. 1 is an explanatory diagram showing the configuration of a large-diameter pipe thickness measuring system according to an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing the configuration of the large-diameter pipe thickness measuring system. 3 is a front view of the main bogie of the large diameter pipe thickness measuring system, FIG. 4 is a plan view of the main bogie of the same large diameter pipe thickness measuring system, and FIG. 5 is a plate thickness measuring system of the same large diameter pipe. FIG. 6 is a side view of the thickness measurement system for the large-diameter tube, FIG. 7 is an enlarged sectional view of a main part of the thickness measurement system for the large-diameter tube, and FIG. FIG. 9 is a front sectional view of the rear wheel drive unit of the main bogie of the tube thickness measuring system, FIG. 9 is a side cross sectional view of the rear bogie drive unit of the large diameter pipe thickness measuring system, and FIG. FIG. 11 is a front cross-sectional view of a child bogie of the large diameter pipe thickness measuring system, FIG. 11 is a plan view of a child bogie of the large diameter pipe thickness measuring system, and FIG. 12 is a child of the large diameter pipe thickness measuring system. FIG. 13 is a front cross-sectional view of the car, and FIG. 13 is a front view showing a mounting state of a distance meter of the large-diameter pipe thickness measuring system. FIG. FIG. 15 is a cross-sectional view, FIG. 15 is an explanatory view showing a measurement width of the large-diameter pipe plate thickness measuring system by the ultrasonic sensor, and FIG. 16 is a description of a measurement result displayed on a display device of the large-diameter pipe plate thickness measurement system. FIG.
[0011]
As shown in FIGS. 1 to 4, a large-diameter pipe thickness measuring system 10 according to an embodiment of the present invention includes four traveling wheels 11 a each of which is driven by a tire made of rubber, which is a soft material. 11d, for example, a main bogie 14 that can run on the inner surface 13 of a large-diameter pipe 12 buried underground or under concrete, and a large-diameter pipe 12 fixed to the bottom of the front and rear ends of the main bogie 14. Magnets 15 and 16 having a small gap S with the inner surface 13 of the main bogie 14 and having magnetic force capable of fixing the main bogie 14 to an arbitrary position on the inner surface 13 of the large-diameter tube 12, and two rows in the traveling direction of the main bogie 14. It is arranged in a zigzag manner, and is provided on the parent carriage 14 so as to be able to move up and down and swing back and forth, and is always urged to the inner surface 13 of the large-diameter tube 12, and each has four small wheels 69 a to 69 d. Six child trolleys 17 facing the same direction as the trolley 14 And a 2.
[0012]
As shown in FIGS. 1 to 4, the large-diameter pipe thickness measuring system 10 is further provided on each of the small carts 17 to 22 and has a small gap s ( (Refer to FIG. 10), a reflection type ultrasonic sensor 23 disposed with the ultrasonic sensor 23, a multi-channel type ultrasonic controller 24 for simultaneously operating the ultrasonic sensor 23, the ultrasonic sensor 23 and the inner surface 13 of the large-diameter tube 12. A water supply means 25 for supplying the medium water to the gap s formed between the main carriage 14 and a distance meter 26 provided at a position different from the ultrasonic sensor 23 on the main carriage 14 for measuring the traveling distance of the main carriage 14. And a data processing personal computer 27 having a display 118 as an example of a display device to which the output of the distance meter 26 and the output of the multi-channel ultrasonic controller 24 are input. Hereinafter, these will be described in detail.
[0013]
As shown in FIGS. 3 to 6, the main carriage 14 is provided at a central portion in the traveling direction (front-rear direction) and mainly has a rectangular base frame portion 28 in plan view, and a screw at a rear end portion of the base frame 28. The vehicle includes a rear wheel drive unit 29 connected by fastening, and a front wheel drive unit 31 connected to a front end of the base frame unit 28 via a swinging fixed shaft 30. Accordingly, the front wheel drive unit 31 swings about the swing fixed shaft 30 in the range of about ± 6 ° with respect to the horizontal direction with respect to the rear wheel drive unit 29 and the base frame unit 28. .
On the left and right side plates 62 and 63 of the base frame portion 28 having a hollow portion, elliptical notches 32 are formed at four positions in front, rear, up and down, and the inside can be observed through the notches 32, and The weight of the base frame 28 is reduced.
[0014]
As shown in FIGS. 3, 4 and 6, two rear running wheels 11 a and 11 b are provided on the left and right sides of the rear wheel driving unit 29, and the running wheels 11 a and 11 b are independent of each other. It is configured to be rotationally driven via provided reduction motors 33, 34 and drive mechanisms 35, 36 connected to the reduction motors 33, 34, respectively. The reduction motors 33 and 34 are DC motors to which a speedometer generator is attached.
[0015]
As shown in FIG. 8 and FIG. 9, the drive mechanism 35 (36 is different from 35) has a gear 38 provided on the output shaft 37 of the reduction motor 33 and a gear 39 meshing with the gear 38 at one end (front side). ), A worm shaft 41 having a worm 40 formed at the center, and a wheel drive shaft 43 having a worm wheel 42 meshed with the worm 40 mounted at the center. A traveling wheel 11a is rotatably provided at the portion (right side). The worm shaft 41 is rotatably supported by bearings 44 and 45 provided in the housing 48, and the wheel drive shaft 43 is also rotatably supported by bearings 46 and 47 provided in the housing 48.
[0016]
As shown in FIGS. 3 and 6, a rectangular plate-shaped magnet 16 is attached to the lower surface of the rear wheel drive unit 29 via a case 16a, and the traveling direction of the traveling wheels 11a, 11b and the case 16a is determined. The center positions are almost the same. Therefore, even if the traveling wheels 11a and 11b move up and down with respect to the traveling surface, the magnet 16 can maintain a small gap S with the inner surface 13 of the large diameter pipe 12.
[0017]
As shown in FIGS. 3 to 5, similarly to the rear wheel driving unit 29, two front running wheels 11 c and 11 d are provided on the left and right of the front wheel driving unit 31, and the running wheels 11 c and 11 d are provided. Are rotationally driven via independently provided reduction motors 49 and 50 and drive mechanisms 35 and 36 connected to the reduction motors 49 and 50, respectively. The reduction motors 49 and 50 are also DC motors to which a speedometer generator is attached.
[0018]
As shown in FIGS. 4 and 7, between the drive mechanisms 35 and 36 of the front wheel drive unit 31, a swing frame 51 having a U-shaped cross section that is detachable by screwing is provided. The swinging fixed shaft 30 that connects the base frame portion 28 and the front wheel drive portion 31 includes a flange portion 53 that abuts on the front side surface 52 of the base frame portion 28, and both front and rear side surfaces 54, 55 of the swing frame 51. And a sliding portion 58 that slides in the sliding holes 56 and 57 formed in the hole. Therefore, the swing frame 51 can swing around the swing fixed shaft 30 fixed to the base frame portion 28.
[0019]
As shown in FIGS. 3 and 5, the center positions of the traveling wheels 11 c and 11 d and the swing frame 51 in the traveling direction substantially coincide with each other, and a rectangular plate-shaped magnet formed of a plurality of blocks is provided on the lower surface of the swing frame 51. 15 is attached via a case 15a. Therefore, even if the traveling wheels 11 c and 11 d swing the swing frame 51 due to the unevenness of the inner surface 13 of the large-diameter tube 12, the magnet 15 can maintain a small gap S with the inner surface 13 of the large-diameter tube 12. . Reference numeral 59 in FIG. 7 denotes an oil seal for preventing medium water from entering the sliding portion 58, and reference numeral 60 denotes a mounting nut screwed into a male screw formed on the front end of the swinging fixed shaft 30. Reference numeral 61 denotes a rotation stopper that regulates the swing angle of the swing frame 51.
[0020]
As shown in FIGS. 3 and 4, mounting seats 64 and 65 are provided at upper ends of side plates 62 and 63 in the left and right direction of the base frame portion 28, and most of the rectangular frame-shaped sensor holding frame 66 in a plan view is It is provided in the base frame part 28. The child bogies 17 to 22 are arranged in two rows and in a staggered manner in the traveling direction of the base frame part 28 constituting the parent bogie 14. The three front carriages 17 to 19 are attached to the front side plate 67 of the sensor holding frame 66 at a pitch P along the left-right direction, while the three rear carriages 20 to 22 are mounted on the sensor holding frame 66. To the rear side plate 68 of the application frame 66 at a pitch P along the left-right direction facing the sub-cars 17 to 19, and at the same time, pitch (P / 2) relative to the sub-cars 17 to 19 along the left-right direction. Installed. In addition, the distance between the child carts 17 to 19 and the child carts 20 to 22 in the front-rear direction is represented by K.
[0021]
That is, the interval K between the sub-cars 17 to 19 and the sub-cars 20 to 22 is arranged so as to exceed the interference area of the ultrasonic sensor 23 mounted on the adjacent sub-cars 17 to 22, and The pitch P between the sub-cars 17 to 19 and between the sub-cars 20 to 22 is arranged in a range of more than one time and less than two times the lateral effective flaw detection width W of one ultrasonic sensor 23. The zigzag arrangement of the front carriages 17 to 19 and the rear carriages 20 to 22 in this manner is as follows.
[0022]
Each ultrasonic sensor 23 has a certain measurement width in the flaw detection area, but is provided on each of the small carts 17 to 22, so that the small wheels 69a to 69d and the small wheels constituting the small carts 17 to 22 are formed. The presence of a frame or the like on which the 69a to 69d is mounted necessarily limits the approach distance (pitch P) between the adjacent ultrasonic sensors 23 in the same row. For this reason, for example, a band-shaped unmeasurable region is generated at an intermediate portion between the adjacent ultrasonic sensors 23 in the front row. The band-shaped unmeasurable area on the front side caused by the traveling of the carriages 17 to 19 can be measured by the ultrasonic sensors 23 of the rear carriages 20 to 22.
[0023]
The ultrasonic pulse of each ultrasonic sensor 23 is emitted from the whole surface of the sensor, but the ultrasonic pulse emitted from a narrower portion (effective beam width) can be effectively used for measurement. Therefore, the pitch P between the adjacent ultrasonic sensors 23 in the same row is a width that does not interfere with the adjacent ultrasonic sensors 23 (that is, a range exceeding one time the lateral effective flaw detection width W), and the horizontal direction It is less than twice the direction effective flaw detection width W.
Further, the width of the unmeasurable region by the plurality of ultrasonic sensors provided in a line becomes too wide, for example, when the unmeasurable region has a width of half or more of the pitch of each ultrasonic sensor, the plurality of ultrasonic sensors However, since the entire measurement area cannot be covered even when the two ultrasonic sensors are arranged in two rows, it is necessary to provide a plurality of ultrasonic sensors in three or more steps. The reflection type ultrasonic sensor 23 used in this embodiment is, for example, a divided type ultrasonic sensor having a transmitter and a receiver separately.
[0024]
As shown in FIGS. 3, 4, and 10 to 12, each of the carriages 17 to 19 (same for 20 to 22) provided with the ultrasonic sensor 23 is a gimbal mechanism which is an example of a universal joint mechanism. Are attached to the front side and the rear side plates 67 and 68 of the sensor holding frame 66 through the vertical direction and the horizontal direction of the sensor holding frame 66 (the radius of curvature K of the inner surface 13 of the large-diameter tube 12). Irrespective of the unevenness of the inner surface 13), the four small wheels 69a to 69d provided at the lower part of the child carriage 19 (18 and 17 are the same) can always run in contact with the inner surface 13 of the large-diameter pipe 12. It has become. Therefore, the ultrasonic sensor 23 provided on the child trolley 19 can always maintain a constant gap s with the inner surface 13 of the large-diameter tube 12 when the parent trolley 14 moves.
[0025]
As shown in FIGS. 10 to 12, a rectangular plate-shaped holder base 70 is provided at the front end of the sub-truck 19 in the vertical direction, and is formed at the upper end of the holder base 70 at intervals in the vertical direction. The two engaging projections 71, 72 thus engaged are engaged with engaging recesses formed on the rear surface of the front side plate 67 of the sensor holding frame 66, and the holder base 70 is screwed to the front side plate 67 of the sensor holding frame 66. I have.
On the rear side of the lower portion of the holder base 70, guide members 73 and 74 having concave portions are provided at parallel intervals in the left-right direction. A slide ball 75 that slides in the recesses of the guide members 73 and 74 is provided at the front end of the lower end, and is provided at an intermediate portion of the slide member 76 that moves vertically and a rear surface 77 near the engaging projection 72 of the holder base 70. A coil spring 79 is provided between the spring stopper 78 and the spring stopper 78. The slide member 76 is constantly urged downward via the coil spring 79.
[0026]
As shown in FIGS. 10 to 12, a bolt-shaped rotation shaft 82 rotatably supported by two bearings 80 and 81 arranged in series in the front-rear direction is provided at the lower end of the slide member 76. A U-shaped (bifurcated) arm 83 having an opening at the rear in a plan view is fixed to the rear end of the rotating shaft 82. Bearing metals 84, 85 are attached to both rear ends of the arm 83, and are provided with mounting bolts 86, 87 sliding on the inner peripheral surfaces of the bearing metals 84, 85. A letter-shaped sensor holder 88 is provided. Small wheels 69a to 69d are rotatably provided at four corners in the front, rear, left and right directions of the lower end of the sensor holder 88 via bearings 89a to 89d.
[0027]
With this configuration, the sensor holder 88 can rotate about the bearing metal 84 and 85 together with the mounting bolts 86 and 87 with respect to the arm 83, while the arm 83 rotates about the rotation axis 82 with respect to the slide member 76. Further, the slide member 76 to which the rotating shaft 82 is attached slides up and down with respect to the guide members 73 and 74. That is, the child bogies 17 to 22 are provided so as to be able to move up and down with respect to the parent bogie 14 and to be able to swing in the front-rear direction.
[0028]
As shown in FIG. 10, a nipple 90 for supplying medium water below the ultrasonic sensor 23 is screwed into the upper part of the front end of the sensor holder 88, and a vertical flow communicating with the lower end of the nipple 90 is provided. A path (not shown) is formed up to the lower end surface 88 a of the sensor holder 88.
Above the rear end of the sensor holder 88, a sensor holding block 91 for fixing the ultrasonic sensor 23 is attached by screw fastening, and above the sensor holding block 91, below the ultrasonic sensor 23. A nipple 92 for supplying medium water is screwed in, and a vertical flow path (not shown) communicating with the lower end of the nipple 90 is formed up to the sensor holding block 91 and the lower end surface 88 a of the sensor holder 88.
[0029]
On the lower end surface 88a of the sensor holder 88, a rectangular frame-shaped water stopper 93 is provided by screw fastening. With this configuration, the medium water supplied via the nipples 90 and 92 is supplied to the lower surface of the ultrasonic sensor 23. And the inner surface 13 of the large-diameter tube 12. Thereby, the ultrasonic wave oscillated from the ultrasonic sensor 23 is reliably propagated to the inner surface 13 of the large-diameter tube 12, and the reflected waves from the inner surface 13 and the outer surface 13a of the large-diameter tube 12 are also reliably transmitted to the ultrasonic sensor 23. Propagated.
[0030]
As shown in FIGS. 3, 4 and 6, a rectangular parallelepiped manifold 94 is provided on the rear side plate 68 of the sensor holding frame 66 by screw fastening. One nipple 94a is attached, and a flow path communicating with the nipple 94a and six branch flow paths branched from the flow path are formed in the manifold 94, and the downstream ends of the six branch flow paths are formed. Are connected to six nipples 95a to 95f on the discharge side provided on the upper surface of the manifold 94, respectively. By connecting the nipples 95a to 95f and the nipples 90 and 92 provided on the sub-carts 17 to 22 by a vinyl hose (not shown) that branches into two, medium water supplied via the nipple 94a Can be supplied directly below the ultrasonic sensor 23 via the nipples 90 and 92.
[0031]
As shown in FIGS. 3 and 4, the distance meter 26 is provided in the vicinity of the traveling wheel 11 a of the rear wheel drive unit 29, and is located at a position different from the ultrasonic sensor 23 attached to the child carriages 17 to 22. Is provided.
[0032]
As shown in FIGS. 3, 13, and 14, similarly to the traveling wheels 11 a to 11 d of the main bogie 14, the distance meter 26 is made of nylon that constantly contacts and rolls with the inner surface 13 of the large-diameter pipe 12 during traveling. A length measuring roller 96 made of a soft material is provided. The distance meter 26 includes an L-shaped mounting bracket 98 fixed to the frame of the rear wheel drive unit 29 via two upper and lower mounting bolts 97, and a fixed shaft 99 provided at the tip of the mounting bracket 98. A rotating arm 102 that rotates around bearings 100 and 101, a cylindrical coupling case 103 attached to a distal end of the rotating arm 102, and a cylindrical encoder case connected to the coupling case 103. 104 and an encoder cap 105 that covers an end face of the encoder case 104.
[0033]
As shown in FIG. 14, a rotary encoder 106 is mounted in the encoder case 104, and an output shaft 107 of the rotary encoder 106 is mounted on a rotation shaft 109 of the length measuring roller 96 via a magnet coupling 108. I have. Bearings 110 and 111 are provided between the rotating shaft 109 and the coupling case 103, and a length measuring roller 96 is attached to the tip of the rotating shaft 109 via a fixing nut 112.
[0034]
As shown in FIG. 13, between the upper portion of the mounting bracket 98 and the base end of the rotating arm 102, the length measuring roller 96 constantly contacts the inner surface 13 of the large-diameter pipe 12 when the parent carriage 14 is running. A coil spring 113 is provided to urge the rotating arm 102 counterclockwise of the fixed shaft 99 so as to roll. Both ends of the coil spring 113 are connected to a mounting bolt 98 a provided on the mounting bracket 98 and a mounting bolt 102 a provided on the rotating arm 102. With this configuration, the length measuring roller 96 is constantly pressed against the inner surface 13 of the large-diameter tube 12 and rolled by the urging force of the coil spring 113 irrespective of the fluctuation of the inner surface 13 when the main carriage 14 is traveling, so that the measurement is performed. The rotation of the long roller 96 can be transmitted to the rotary encoder 106 via the rotation shaft 109 and the magnet coupling 108. The travel position is measured by the rotary encoder 106, and the measurement position and the measurement plate thickness are corresponded in consideration of the distance between the six ultrasonic sensors 23 arranged in a zigzag manner ahead of the traveling direction and the length measurement roller 96. Let me.
[0035]
As shown in FIGS. 1 to 4, at the rear of the rear wheel drive unit 29, signal lines of each of the six ultrasonic sensors 23, signal lines and power lines connected to the multi-channel ultrasonic controller 24, A cable 114 that bundles signal lines and the like of the rotary encoder 106 is fixed via a cable connector 115. Further, a vinyl hose 117 for supplying medium water stored in a water tank (not shown) by a pump 116 is connected to a nipple 94a provided on the manifold 94 of the base frame portion 28 by a joint. The cable 114 and the vinyl hose 117 are bundled except for both ends. The water supply means 25 includes a water tank, a pump 116, a vinyl hose 117, and pipes in the main carriage 14 after the manifold 94.
[0036]
As shown in FIGS. 1 and 2, in the large-diameter pipe thickness measuring system 10 according to the present embodiment, a personal computer having an arithmetic processing means for performing signal processing of measurement data and a display 118 for displaying the arithmetic processing result. 27 is used. Therefore, the output of the distance meter 26 and the output of the multi-channel ultrasonic controller 24 can be processed by the personal computer 27 and the result can be displayed on the display 118 of the personal computer 27.
[0037]
As shown in FIGS. 1, 2 and 15, the main carriage 14 travels along the inner surface 13 in the circumferential direction of the large-diameter pipe 12, sets the measurement width to H (150 mm in the present embodiment), and sets a lap allowance. R (25 mm in the present embodiment) is provided, the effective measurement width is U (125 mm in the present embodiment), adjacent circumferential measurements are sequentially performed, and the longitudinal direction of the large-diameter tube 12 ( Measurement is performed for a predetermined length in the pipe axis direction).
[0038]
As shown in FIG. 16, the display 118 of the personal computer 27 can output a thickness distribution of a predetermined width (effective measurement width = U) with respect to the measurement position in the inner circumferential direction of the large-diameter tube 12. Are described in different colors on a plane in which the inner circumference of the large-diameter tube 12 is displayed in an expanded state. Specifically, the display A indicates the measurement position in the tube axis direction (in the present embodiment, the measurement width H from the reference position 0 to 250 to 400 mm indicates H = 150 mm), and the display B indicates the six ultrasonic sensors 23 ( Display C shows the minimum thickness on the circumference, display D shows the change in the thickness on the measurement circumference, and display E shows any value. (In the embodiment, the measurement position on the circumference is a position every 4645 mm to 5 mm), the measurement result for each of the six ultrasonic sensors 23 is shown, and the measurement position on the circumference is 4670 For CH3 in which a thinned portion in the range of ４６4690 mm has been detected, the color is changed from that of a healthy portion, and furthermore, it is indicated by a digital value.
[0039]
Next, a plate thickness measuring method using the large diameter pipe thickness measuring system 10 according to one embodiment of the present invention will be described with reference to the drawings. In the main carriage 14, the water piping for supplying the medium water and the wiring between the cable 114, the ultrasonic sensor 23, the rotary encoder 106, and the reduction motors 33, 34, 49, 50 have been completed. And
(1) As shown in FIGS. 1 and 2, the parent carriage 14, the personal computer 27, the multi-channel ultrasonic controller 24, the pump 116 and the like are brought into the large-diameter pipe 12, and the parent carriage 14 and the multi-channel ultrasonic Necessary wiring such as connection of the cable 114 and the vinyl hose 117 between the control device 24 and the pump 116 and piping, and wiring between the personal computer 27 and the multi-channel ultrasonic control device 24, and adjustment work before measurement are performed.
[0040]
(2) The measurement position by the ultrasonic sensor 23 is the reference position in the tube axis direction (0 indicated by the display A in FIG. 16) and the circumferential direction is 0 ° (the lowest position indicated by the display D in FIG. 16), and The parent carriage 14 is arranged so that the traveling direction is the circumferential direction.
(3) By driving the pump 116, the medium water stored in the water tank is connected to the vinyl hose 117, the manifold 94, and the six nipples 95a to 95f of the manifold 94 and the nipples 90 and 92 of the sub carts 17 to 22. The medium water is constantly supplied to the gap s between each ultrasonic sensor 23 and the inner surface 13 of the large-diameter pipe 12 by supplying the water stop 93 provided at the lower part of each of the sub-carts 17 to 22 through a vinyl hose. Fill.
[0041]
(4) The deceleration motors 33, 34, 49, 50 of the main bogie 14 are driven to attract the main bogie 14 to the inner surface 13 of the large-diameter tube 12 by the magnets 15, 16, and the inner surface 13 of the large-diameter tube 12. Self-propelled in the circumferential direction (measuring speed is about 2 m / min).
(5) The thickness of the measuring position of the large-diameter tube 12 and the measuring position by the ultrasonic sensor 23 and the rotary encoder 106 attached to the main trolley 14 via the sub trolleys 17 to 22 while the main trolley 14 is running. Is measured substantially continuously for one revolution in the circumferential direction with a measurement width H = 150 mm. At this time, since the gap s between each ultrasonic sensor 23 and the inner surface 13 of the large-diameter tube 12 is always filled with the medium water, the ultrasonic waves from each ultrasonic sensor 23 are surely propagated to the inner surface 13. The reflected wave from the outer surface 13a of the large-diameter tube 12 is also surely propagated to each ultrasonic sensor 23, so that accurate measurement can be performed.
[0042]
(6) The plate thickness measured by the multi-channel ultrasonic controller 24 based on the output of each ultrasonic sensor 23 and the travel position measured by the rotary encoder 106 are subjected to data processing by the arithmetic processing means of the personal computer 27, As shown in FIG. 16, the result of the arithmetic processing is simultaneously displayed on the display 118 of the personal computer 27.
(7) When the main bogie 14 makes one round in the circumferential direction, the running of the main bogie 14 is stopped, and the main bogie 14 is provided with a lap margin R = 25 mm in the measurement width H on the downstream side. Relocate to the lowest position in the direction.
(8) Thereafter, the above (4) to (7) are repeated to measure a predetermined length in the pipe axis direction of the large diameter pipe 12.
(9) When the measurement operation is completed, the main carriage 14 and the pump 116 are stopped, the connection and the like performed in (1) are returned to the original state, and each part is taken out from the large-diameter pipe 12.
[0043]
The present invention is not limited to the above-described embodiments, and changes can be made without departing from the spirit of the present invention. For example, some or all of the above-described embodiments and modifications are described. A case where the thickness measuring system for a large-diameter pipe according to the present invention is configured in combination is also included in the scope of the present invention.
In the above embodiment, the magnets 15 and 16 are provided before and after the parent carriage 14 (in the vicinity of the traveling wheels 11c and 11d and the traveling wheels 11a and 11b). However, the present invention is not limited thereto. It may be provided at another position of the parent carriage 14, for example, at the center position.
[0044]
The four traveling wheels 11a to 11d are independently driven by reduction motors 33, 34, 49, 50, and the reduction motors 33, 34, 49, 50 include a worm 40 and a worm wheel 42 that meshes with the worm 40. Although the worm speed reducer is provided, the present invention is not limited to this. If necessary, the traveling wheels 11a and 11b and the traveling wheels 11c and 11d are driven by separate reduction motors, and the reduction motor has a brake. Can be provided.
The output of the display device is described by color coding on a plane in which the inner circumference of the large-diameter tube 12 is displayed in an expanded state. However, the present invention is not limited to this, and may be described by other display methods depending on the situation. it can.
[0045]
The tires of the traveling wheels 11a to 11d are made of rubber which is a soft material. However, the present invention is not limited to this. If necessary, another soft material which does not damage the coating layer on the inner surface 13 of the large diameter pipe 12 may be used. No problem.
Although six child carriages 17 to 22 to which the ultrasonic sensor 23 is attached are used, the present invention is not limited to this, and four, five or seven or more can be used depending on the situation.
[0046]
【The invention's effect】
In the system for measuring the thickness of a large-diameter pipe according to any one of claims 1 to 4, it is not necessary to provide a scaffold for measurement as in the related art, and a sub-cart provided with an ultrasonic sensor is used as a master car provided with a magnet. To move the inner surface of the large-diameter pipe so as to be able to move up and down and swing back and forth, and from the output of the distance meter and the ultrasonic sensor, the thickness of the predetermined width with respect to the measurement position in the inner circumferential direction of the large-diameter pipe. By outputting the thickness distribution to the display device, the thickness of the entire large-diameter tube can be measured substantially automatically and continuously. Therefore, the state of surface corrosion of the outer large-diameter pipe can be simultaneously grasped accurately, thereby greatly reducing the burden on the operator.
[0047]
In particular, in the plate thickness measuring system according to the second aspect of the present invention, when the parent bogie travels in the inner circumferential direction of the large-diameter pipe having the concave curved surface, the main bogie can run stably, so that it is more accurate. Stable measurement is possible.
In the system for measuring the thickness of a large-diameter pipe according to the third aspect, since the four traveling wheels are independently driven, the parent trolley can travel to an arbitrary position, whereby the measurement position can be easily adjusted, and In addition, since the worm speed reducer or the speed reducer with a brake is provided, the positioning of the master bogie can be easily performed, thereby improving the measurement accuracy.
In the system for measuring the thickness of a large-diameter pipe according to the fourth aspect, the state of corrosion on the outer surface can be grasped more easily, thereby reducing the burden on the operator and improving the workability of the measurement.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a configuration of a large-diameter pipe thickness measuring system according to an embodiment of the present invention.
FIG. 2 is an explanatory diagram showing a configuration of a large-diameter pipe thickness measuring system.
FIG. 3 is a front view of a main carriage of the large-diameter pipe thickness measuring system.
FIG. 4 is a plan view of a parent carriage of the large-diameter pipe thickness measuring system.
FIG. 5 is a side view of a main bogie of the large-diameter pipe thickness measuring system.
FIG. 6 is a side view of the system for measuring the thickness of the large-diameter tube.
FIG. 7 is an enlarged sectional view of a main part of a main carriage of the large-diameter pipe thickness measuring system.
FIG. 8 is a front cross-sectional view of a rear wheel drive unit of the parent bogie of the large-diameter pipe thickness measuring system.
FIG. 9 is a side sectional view of a rear wheel drive unit of the parent bogie of the large-diameter pipe thickness measuring system.
FIG. 10 is a front sectional view of a child carriage of the large-diameter pipe thickness measuring system.
FIG. 11 is a plan view of a sub-cart of the large-diameter pipe thickness measuring system.
FIG. 12 is a plan cross-sectional view of a child carriage of the large-diameter pipe thickness measuring system.
FIG. 13 is a front view showing an attached state of a distance meter of the large-diameter pipe thickness measuring system.
FIG. 14 is a plan cross-sectional view showing a mounted state of a distance meter of the large-diameter pipe thickness measuring system.
FIG. 15 is an explanatory diagram showing a measurement width of the large-diameter pipe thickness measuring system by an ultrasonic sensor.
FIG. 16 is an explanatory diagram of a measurement result displayed on a display device of the large-diameter pipe thickness measuring system.
[Explanation of symbols]
10: Plate thickness measurement system for large diameter pipes, 11a to 11d: running wheels, 12: large diameter pipe, 13: inner surface, 13a: outer surface, 14: parent carriage, 15: magnet, 15a: case, 16: magnet, 16a : Case, 17 to 22: child carriage, 23: ultrasonic sensor, 24: multi-channel ultrasonic controller, 25: water supply means, 26: distance meter, 27: personal computer, 28: base frame, 29: rear Side wheel drive unit, 30: swing fixed shaft, 31: front wheel drive unit, 32: notch, 33, 34: reduction motor, 35, 36: drive mechanism, 37: output shaft, 38: gear, 39: gear , 40: Worm, 41: Worm shaft, 42: Worm wheel, 43: Wheel drive shaft, 44 to 47: Bearing, 48: Housing, 49, 50: Reduction motor, 51: Swing frame, 52: Front side surface, 5 : Flange portion, 54, 55: Side surface, 56, 57: Sliding hole, 58: Sliding portion, 59: Oil seal, 60: Mounting nut, 61: Detent, 62, 63: Side plate, 64, 65: Mounting Seat, 66: sensor holding frame, 67: front side plate, 68: rear side plate, 69a to 69d: small wheel, 70: holder base, 71, 72: engaging projection, 73, 74: guide member, 75: slide ball , 76: slide member, 77: rear surface, 78: spring stopper, 79: coil spring, 80, 81: bearing, 82: rotating shaft, 83: arm, 84, 85: bearing metal, 86, 87: mounting bolt, 88 : Sensor holder, 88a: lower end surface, 89a to 89d: bearing, 90: nipple, 91: sensor holding block, 92: nipple, 93: water stop, 94: manifold, 4a: Nipple, 95a to 95f: Nipple, 96: Length measuring roller, 97: Mounting bolt, 98: Mounting bracket, 98a: Mounting bolt, 99: Fixed shaft, 100, 101: Bearing, 102: Rotating arm, 102a: Mounting bolt, 103: coupling case, 104: encoder case, 105: encoder cap, 106: rotary encoder, 107: output shaft, 108: magnet coupling, 109: rotary shaft, 110, 111: bearing, 112: fixing Nut, 113: coil spring, 114: cable, 115: cable connector, 116: pump, 117: vinyl hose, 118: display (display device)

Claims (4)

A tire having four running wheels each made of a soft material and driven, and a main bogie capable of running on the inner surface of the large-diameter pipe;
A magnet having a magnetic force fixed to the bottom of the parent bogie, having a small gap with the inner surface of the large-diameter tube, and capable of fixing the main bogie to an arbitrary position on the inner surface of the large-diameter tube;
It is arranged in two rows and in a staggered manner in the traveling direction of the parent bogie, and is provided on the main bogie so as to be able to move up and down and swing back and forth, and is always urged to the large-diameter tube, and each is cooperated with the main bogie. Four or more child bogies with four small wheels facing in the same direction,
A reflection-type ultrasonic sensor provided on each of the sub-carts and arranged with a small gap between the inner surface of the large-diameter tube, and a multi-channel ultrasonic for simultaneously operating the ultrasonic sensors A control device;
Water supply means for supplying medium water to the gap formed between the ultrasonic sensor and the large diameter pipe,
A distance meter that is provided at a position different from the ultrasonic sensor on the master trolley and measures a traveling distance of the master trolley;
A display device having an output of the distance meter and an output of the multi-channel ultrasonic controller as input,
The sub trolleys are arranged beyond the interference area of the ultrasonic sensors mounted on the adjacent sub trolleys, and the sub trolleys in each row have a width of 1 times the lateral effective flaw detection width of the ultrasonic sensors. Placed in a range of more than twice and
The display device outputs a thickness distribution having a predetermined width with respect to a measurement position in an inner circumferential direction of the large-diameter tube from the output of the distance meter and the output of the ultrasonic sensor, Thickness measurement system. 2. The system according to claim 1, wherein said magnets are provided before and after said parent carriage. 3. The system according to claim 1, wherein the four traveling wheels are independently driven by a reduction motor, and the reduction motor has a worm reduction gear or a brake. A thickness measuring system for a large-diameter pipe, wherein a reduction gear is provided. The thickness measurement system for a large-diameter pipe according to any one of claims 1 to 3, wherein an output of the display device is color-coded on a plane in which an inner circumference of the large-diameter pipe is displayed in a developed state. The thickness measurement system for large diameter pipes.

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