JPH05232284A - Inspecting apparatus of piping - Google Patents

Abstract

PURPOSE:To obtain an inspecting apparatus of a piping which brings forth no positional slippage, by a method wherein a guide with an origin marker is provided in the vicinity of a surface to be inspected, while the position of an inspecting unit is detected by a distance sensor of an inspecting mechanism, and a slippage from the surface to be inspected is corrected, in a running-type inspecting apparatus not using a track for exclusive use. CONSTITUTION:In an inspecting apparatus having a moving mechanism 8 running in the circumferential direction on the surface of a piping or the like and a slide mechanism 4 making an inspecting unit slide in the axial direction, a guide which is provided at a position being in the vicinity of a part to be inspected and not interfering with the main frame 9 of the inspecting apparatus, an origin marker 12 provided on at least one place of this guide, and an inspecting part 1 which is made up of a distance sensor 5 detecting a distance between the guide provided for the main frame 9 of the inspecting apparatus and the main frame 9 of the inspecting apparatus and of an origin sensor 6 detecting the origin marker 12, are provided. Moreover, a storage circuit receiving signals from the distance sensor 5 and the origin sensor 12 and signals from the slide mechanism 4 and the moving mechanism 8 as inputs and storing them and a operation processing circuit calculating and correcting a positional slippage accompanying scanning of the inspecting unit over the part to be inspected which is set beforehand, are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inspection device for inspecting pipes and the like in various plants such as a nuclear power plant, and more particularly to a pipe inspection device with improved inspection position accuracy.

[0002]

2. Description of the Related Art Conventionally, for nondestructive inspection of pipes and the like in various plants, an annular track is attached to the outer periphery of the pipe to be inspected, and the inspection device is moved along this track to perform ultrasonic probe or the like. The inspection was carried out by scanning the inspection head with the built-in detector.

However, the work of attaching and detaching the inspection device to the track is heavy on the operator, and it is necessary to prepare a dedicated track and inspection device according to the diameter of the pipe, which is inferior in workability and economical efficiency. Therefore, a traveling inspection device that does not use a dedicated track is being studied.

[0004]

In a traveling type inspection apparatus which does not use a dedicated track, for example, when the pipe is a magnetic body, a method of adsorbing to the surface of the pipe by magnetic wheels and moving the flexible belt is used. There is a method of winding around the pipe and moving it, but in any case the inspection device is not fixed to the pipe with a dedicated track, so it is a small amount due to slip of magnetic wheels and loosening of flexible belt, but it is an inspection There has been a demand for a self-propelled inspection device that can accurately maintain the inspection position because it may be displaced from the position.

An object of the present invention is to provide a guide with an origin marker in the vicinity of the surface to be inspected in a traveling type inspection apparatus that does not use a dedicated track, and detect the position of the inspection device by a distance sensor of the inspection mechanism. In addition, it is to provide a pipe inspection device that corrects the deviation from the surface to be inspected and does not cause a positional deviation.

[0006]

In an inspection apparatus having a moving mechanism that travels in the circumferential direction on the surface of a pipe or the like and a slide mechanism that slides an inspecting device in the axial direction of the pipe or the like, the inspection is installed near the portion to be inspected. A guide provided at a position where it does not interfere with the main body, an origin marker provided at least at one place of this guide, a distance sensor for detecting the distance between the guide provided on the inspection device body and the inspection device body, and the origin. An inspection unit including an origin sensor that detects a marker, a storage circuit that inputs and stores signals from the distance sensor and the origin sensor and signals from the slide mechanism and the movement mechanism, and the inspection of a preset inspection target portion. It is characterized by comprising a control unit equipped with a calculation / processing circuit for calculating and correcting a positional deviation due to the scanning of the vessel.

[0007]

The origin marker and the guide provided near the portion to be inspected confirm the origin position of the inspection device and the inspection apparatus main body before the start of operation with the origin marker, and after the operation, the guide displaces the inspection device in the portion to be inspected. Is detected, and the inspection is performed while the position of the inspection device is always accurately corrected by the control unit based on this deviation and the origin position.

[0008]

An embodiment of the present invention will be described with reference to the drawings.

The pipe inspection apparatus comprises an inspection unit 1 and a control unit 20. FIG. 1 is a plan view showing the pipe mounting of the inspection unit 1, and FIGS. 2 and 3 are front views of FIG. It is a side view.

The inspection unit 1 includes an inspection head 3 having a detector 2 such as an ultrasonic probe, a slide mechanism 4 for sliding the inspection head 3 in the axial direction of the pipe 30, and a distance from the slide mechanism 4. Inspection device main body 9 including moving mechanism 8 in which sensor 5, origin sensor 6 and wheels 7 are arranged, and piping 30
The flexible belt 10 that holds the inspection device body 9 attached to the outer periphery of the pipe 30 and moves in the circumferential direction is parallel to the position 31 to be inspected in the pipe 30, and is attached to the outer periphery of the pipe 30 so as not to interfere with the movement of the inspection device. It is formed of a guide belt 11 which is a guide attached in an annular shape, and an origin marker 12 attached on the guide belt 11.

As shown in the control system diagram of FIG. 4, the control unit 20 stores a memory circuit 21 for storing various distance data detected by the distance sensor 5 of the inspection unit 1 and a correction value based on the distance data. Is formed by an arithmetic circuit 22 that outputs a control signal to the inspection unit 1 in order to obtain the signal, a bus 23 that connects these, and interfaces 24, 25, 26, 27, and 28.

The interface 24 is an operation panel 29 for inputting arbitrary parameters, and the interface 25 is a rotating motor 13 for driving the moving mechanism 8 of the inspection apparatus body 9 and an encoder 14 for rotating the rotating motor 13. Further, it is connected to a rotation driver 15 that controls the rotation motor 13.

The interface 26 is connected to a slide motor 16 for driving the slide mechanism 4, a slide encoder 17, and a slide driver 18 for controlling the slide motor 16. In addition, the interface 27,
Reference numerals 28 are connected to the distance sensor 5 and the origin sensor 6, respectively, so that both can access each other. Next, the operation of the above configuration will be described by taking the inspection of the welded portion on the outer periphery of the pipe 30 as an example.

First, the inspection device main body 9 is attached to the outer periphery of the pipe 30 as the inspection object by the flexible belt 10. Piping
The ultrasonic probe detector 2 incorporated in the inspection head 3 slidably provided in the slide mechanism 4 is aligned with the inspected position 31, which is the welded portion on the outer periphery of the periphery 30.

Further, an annular guide belt 11 is provided on the outer circumference of the pipe 30 so as to be parallel to the inspected position 31 and not interfere with the scanning of the inspection apparatus body 9 and the inspection head 3 so as to face the distance sensor 5. And mount the origin marker 12 on the guide belt 11.

Here, as shown in FIG. 1, in the axial direction of the pipe 30, the distance between the inspection device body 9 and the guide belt 11 at the origin position P ₀ is l ₀ , and the length of the inspection device body 9 is L, The distance between the moving inspection device body 9 and the guide belt 11 is l
₁ , the distance between the moving detector 2 and the inspection device body 9 is l ₂
The symbol l ₃ is the distance between the detector 2 and the guide belt 11, and the symbol l _2S is the distance between the detector 2 and the inspection apparatus body 9 at the origin position P ₀ .

With respect to the annular inspection position 31, for example, the detector 2 built in the inspection head 3 also inspects the vicinity of the inspection position 31 so that an arrow line A shown in the plan view of FIG.
Alternatively, the circumferential movement amount r and the axial movement amount t are set so that the locus becomes as shown by the arrow B in the plan view of FIG.
The surface of the inspected position 31 is scanned for inspection. Note that FIG.
Indicates the case where the circumferential movement amount r is the entire outer circumference of the pipe 30. Next, the operation procedure of the inspection will be described. Since the shape of the flexible belt 11 that supports the inspection device body 9 can be changed flexibly, it can be easily applied to pipes of various diameters.

However, for example, when the pipe 30 to be inspected is installed vertically as shown in FIG. 1 and the inspection device main body 9 is always pulled downward by gravity, as shown in FIG. As the movement of the inspection apparatus main body 9 in the circumferential direction due to the scanning locus (arrow lines A and B) of the detector 2 as shown in FIG. 6 is repeated, the distance l ₁ between the inspection apparatus main body 9 and the guide belt 11 becomes spiral. It will be shortened little by little. Therefore, it is necessary to correct the error caused in the distance l ₁ as needed. First, a calculation method for error correction will be described.

As shown in FIG. 1, the distance l ₀ between the inspection device main body 9 and the guide belt 11 at the origin position P _0, and the distance between the detector 2 built in the inspection head 3 and the inspection device main body 9 during movement. the absolute value of the difference between l ₁ is the absolute value of the difference of the distance l ₂ between the detector 2 and the testing device body 9 in the moved distance l _2S of the inspection apparatus main body 9 and the detector 2 at the origin position P ₀ In the same manner as above, if the distance l ₁ decreases, the distance l ₂ increases, and if the distance l ₁ increases, the distance l ₂ decreases. Therefore, when the absolute value of this difference is l ₀ > l ₁ , the distance l _2S becomes Pull again, l ₀ <l ₁
In the case of, the distance l ₂ is corrected by adding to the distance l _2S , and the distance l ₃ is always maintained constant.

As shown in FIGS. 5 and 7 for explaining the correction operation in the inspection section, the detector 2 is moved in the tube axis direction by t every time the inspection apparatus main body 9 is moved in the tube circumferential direction by r. If is, in turn, the distance l ₀ + t is the reference distance, the distance by an operation similar correction value to the distance l _2S + t l ₂
It can be seen that + t is corrected and the distance l ₃ + t is kept constant. Next, calculation / processing in the control unit 20 will be described with reference to the operation flow chart of FIG. Figure 4 in step S ₁
The arithmetic circuit 22 and the memory circuit 21 of the control unit 20 shown in are initialized. In step S ₂ , the origin marker 12 on the guide belt 11 is detected by the origin sensor 6 and input to the memory circuit 21 via the interface 28 and the bus 23.

In step S ₃ , the operation panel 29 is used to input the parameters of the movement amount r of the inspection apparatus body 9 in the pipe circumferential direction, the movement amount t of the inspection device 2 in the pipe axis direction, and the number of times n of repetition of the operation.

In step S ₄ , the step S ₂
Between the inspection device body 9 and the guide belt 11 at
₀ is detected by the distance sensor 5 mounted on the inspection apparatus main body 9 and recorded in the memory circuit 21 via the interface 27 and the bus 23 to be used as reference gap data.

[0023] The distance l ₀ of the reference gap data at step S _5, the tester 2 and the distance l ₃ of the guide belt 11, and the axial distance L of the inspection apparatus main body 9, the tube axis direction initial distance l _2S (distance between the inspection device 2 and the inspection device main body 9 after origin processing) is calculated by the arithmetic circuit 22. Further, based on the distance l _2S which is the result of this calculation, the output of the tube axis direction operation is output to the slide motor 16 via the bus 23, the interface 26, and the slide driver 18.

In step S ₆ , based on the parameters t, r and n input in step S ₃ , the rotation motor 13 is operated in the circumferential direction via the bus 23, the interface 25 and the rotation driver 15. Output.

In step S _{7, the} slide motor 16
Along with the movement of the inspection device body 9 due to the operation of the rotation motor 13 and the rotation motor 13, the distance l ₁ between the inspection device body 9 and the guide belt 11 is increased.
Is detected by the distance sensor 5.

In step S ₈ , the step S
_The distance l ₁ detected by ₇ is interface 27 and bus 23
The via, obtains a correction value from the deviation amount of the distance l ₀ a tube axis direction on the basis of the reference gap data in the arithmetic circuit 22, and calculates the distance l ₂ of the accurate tube axis direction, the bus 23 and the interface 26 , And the correction control output to the slide motor 16 via the slide driver 18 to correct the deviation in the pipe axis direction of the inspection device 2 which is being moved in the pipe circumferential direction by the inspection device body 9.

In step S ₉ , "input (l ₁ ) → correction {l _2S + (l ₁ -l ₀ )} →" is detected by detecting the distance l _1.
The calculation / processing of "output (l ₂ )" is repeated until the inspection apparatus main body 9 has moved in the pipe circumferential direction by one pitch (pipe circumferential direction movement amount r), and this is detected by the rotary encoder 14. In step S _{10, the} inspector 2 is moved in the tube axis direction by one pitch (tube circumferential direction movement amount t) and the correction operation in the tube axis direction is repeated.

In step S ₁₁ , the above steps S ₉ and S _{10 are performed.}
The process of “after activation → completion of 1 pitch movement in the pipe circumferential direction → completion of movement of 1 pitch in the pipe axis direction” is repeated n times to move the inspection device main body 9 sequentially along the outer circumference of the pipe to move the inspection device 2 to the inspected position 31.
The ultrasonic inspection of the position 31 to be inspected is performed by accurately scanning along a predetermined locus with respect to the arrow line A in FIG.

As described above, the distance l ₂ between the inspection device 2 built in the moving inspection head 3 and the inspection device main body 9 is corrected to make the distance l ₃ between the inspection device 2 and the guide belt 11 constant. By keeping it, the displacement of the inspection device 2 from the inspected position 31 due to the movement of the inspection device body 9 and the like is prevented.

Therefore, in the pipe inspection device for moving the inspection device main body 9 by the flexible belt 10 which is lightweight and has a wide range of application, the positioning of the inspection device 2 with respect to the inspected position 31 is automatically corrected, so that the inspection efficiency is improved. Is improved.

In the above embodiment, the inspection device body 9
As an example of the moving means, the self-propelled type using the flexible belt 10 has been taken as an example, but the present invention can obtain the same action and effect even if the moving means is not the flexible belt or the self-propelled type.

[0032]

As described above, according to the present invention, in the self-propelled pipe inspection device having a wide range of application, the inspection position is automatically corrected to promote the automation of the work, thereby improving the safety and reliability of the pipe. Lead to

[Brief description of drawings]

FIG. 1 is a plan view showing pipe installation of an inspection unit according to the present invention.

FIG. 2 is a front view of FIG.

FIG. 3 is a side view of FIG.

FIG. 4 is a system configuration diagram of a control unit according to the present invention.

FIG. 5 is a plan view of an inspection unit showing an example of an inspection device scanning locus.

FIG. 6 is a plan view of an inspection unit showing another example of the inspection device scanning locus.

FIG. 7 is an explanatory diagram of a correction operation in the inspection unit.

FIG. 8 is an operation flowchart of the control unit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Inspection part, 2 ... Detector, 3 ... Inspection head, 4 ... Sliding mechanism, 5 ... Distance sensor, 6 ... Origin sensor, 8 ... Moving mechanism, 9 ... Inspection device main body, 10 ... Flexible belt, 11 ...
Guide belt, 12 ... Origin marker, 13 ... Rotation motor,
16 ... slide motor, 20 ... control unit, 21 ... arithmetic circuit, 22
… Memory circuit, 23… Bus, 29… Operation panel, 30… Piping, 31
… Inspected position.

Claims (1)

[Claims] 1. An inspection apparatus having a moving mechanism that travels in the circumferential direction on the surface of a pipe or the like and a slide mechanism that slides an inspection device in the axial direction of the pipe or the like, which does not interfere with the inspection installation main body in the vicinity of the inspected part. A guide provided at a position, an origin marker provided at least at one or more places of the guide, a distance sensor for detecting a distance between the guide provided in the inspection apparatus body and the inspection apparatus body, and the origin marker are detected. An inspection unit consisting of an origin sensor, a memory circuit for inputting and storing signals from the distance sensor and the origin sensor and signals from the slide mechanism and moving mechanism, and for scanning the inspection device with respect to a preset inspection target portion. A pipe inspection device comprising a control unit equipped with a calculation / processing circuit for calculating and correcting a positional shift involved.