JPH0687857U - In-pipe inspection tool positioning device - Google Patents

Abstract

(57) [Summary] [Purpose] A pipe inspection tool positioning device that accurately and simply positions the inspection tool on a portion to be inspected in the pipe to improve the workability of positioning work and reduce the number of work steps. And so on. The centering means 11 comprises a bendable guide tube 3 which is inserted into a pipe 2 and has an inspection tool 5 at its tip, and a plurality of centering means 11 which are arranged at intervals in the longitudinal direction. The fixing member 12, the sliding member 13 slidably arranged in the longitudinal direction of the guide tube 3, the biasing means 14 connecting them, and the sliding member 1.
3 and the fixing member 12, which are arranged at intervals in the circumferential direction, are provided with rolling elements 17 that are projected outward in the radial direction of the guide tube 3 by the biasing means 14 and are brought into close contact with the inner surface of the pipe 2. By arranging the tube 3 along the center line of the pipe 2, the insertion length of the guide tube 3 and the pipe length are matched.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a positioning device for an inspection tool which is arranged in a pipe to inspect the pipe.

[0002]

[Prior art]

 A radiation transmission test (RT) is one of the inspection methods for piping. In this radiation transmission test, a radiation source such as iridium is placed inside the inspected part to be inspected, for example, inside the pipe at the welded part of the pipe, and a film is placed on the outer peripheral surface of the welded part. Then, the soundness of the weld is inspected by analyzing the image taken on the film by the radiation transmitted through the pipe. Therefore, in order to efficiently irradiate the emitted radiation to the film with uniform intensity over the entire circumference, the radiation source as an inspection tool arranged in the pipe runs along the longitudinal direction of the pipe. The position and the center of the pipe must be accurately positioned.

Conventionally, as a radiation source positioning device, one having a structure shown in FIGS. 4 and 5 can be cited. The positioning device 1 includes a guide tube 3 which is inserted from an open end 2a of a pipe 2 to a position where a tip 3a of the pipe 2 is arranged in the vicinity of a welded portion X to be inspected. The tip end 3a of the guide tube 3 is provided with a centering means 4 for arranging the tip end 3a at the center position of the pipe 2, and the radiation source 5 is stored at the rear end of the guide tube 3 during transportation. The radiation source storage container 6 is attached. In addition, the guide tube 3 includes a radiation source operating means 7 for moving the radiation source 5 forward and backward from the radiation source storage container 6 along the guide tube 3, and a tip position detection for detecting the position of the tip 3a of the guide tube 3. Means 8 and are provided.

The radiation source 5 is a columnar member made of a radioactive substance such as iridium as in the conventional example, and has a wire 7a described later attached to one end thereof. The radiation source 5 can be moved in the pipe 2 by pushing and pulling the wire 7a.

The guide tube 3 is, for example, a flexible tube formed by coating the outer surface of a stainless steel mesh with vinyl. When the guide tube 3 is inserted into the pipe 2, the guide tube 3 bends freely according to the bending of the pipe 2. The tip 3a can be arranged in the vicinity of the welded portion X. In this case, since the guide tube 3 is not arranged along the center line of the pipe 2 but is arranged in the pipe 2 in a meandering or spiral shape, its insertion length is equal to the pipe length. Not equal. Therefore, at least the centering means 4 for arranging the tip 3a of the guide tube 3 at the center of the pipe 2 and the tip position detecting means 8 for detecting the tip 3a of the guide tube 3 are required.

The centering means 4 is a balloon-shaped expandable member 4 a which is attached to the distal end 3 a of the guide tube 3 so as to seal the distal end opening of the guide tube 3 and is expandable and contractable in the radial direction, and the guide tube. 3 is provided with an air pressure supply means (not shown) for supplying air pressure to expand the elastic member 4a. The elastic member 4a is formed in a substantially cylindrical shape, and its outer diameter dimension is sufficiently smaller than the inner diameter dimension of the pipe 2. Then, when the air pressure is supplied from the air pressure supply means, the air pressure is supplied to the elastic member 4a through the guide tube 3 and the elastic member 4a is expanded in the radial direction, so that the distal end 3a of the guide tube 3 is positioned. The device can be placed at the center of the pipe 2. In FIG. 4, reference numeral 4b is an air tube connected to the air pressure supply means.

The radiation source operating means 7 includes, for example, a wire 7a attached to the radiation source 5, a reel (not shown) for winding or unwinding the wire 7a, and a motor (not shown) for rotating the reel. And a control means 7b for instructing the driving / rotational direction of the motor and the like, and moving the radiation source 5 in the guide tube 3 as necessary, or storing it in the radiation source storage container 6. You can do it.

The tip position detecting means 8 counts the number of voltage pulses generated by the scintillation probe 8b, and a detection part 8c including a collimator 8a and a scintillation probe 8b arranged outside the welding part X, for example. And a scintillation counter 8d for measuring the intensity of radiation.

In order to position the radiation source 5 in the vicinity of the welded portion X in the pipe 2 by the positioning device 1 for the radiation source 5 configured as described above, first, a guide attached to the radiation source storage container 6 is used. The tube 3 is inserted through the open end 2a of the pipe 2 and moved together with the radiation source storage container 6 in which the radiation source 5 is stored. As a result, the tip of the guide tube 3 is arranged near the welded portion X. Next, the radiation source operating means 7 is operated to feed the radiation source 5 stored in the radiation source storage container 6 into the guide tube 3 and to the inside of the elastic member 4a attached to the tip 3a of the guide tube 3. To reach.

When the scintillation counter 8d is observed in this state, when the radiation source 5 passes through the weld X, the count amount of the scintillation counter 8d reaches a peak. Therefore, by stopping the movement of the radiation source 5 at this time, the radiation source 5 can be arranged at an optimum position along the longitudinal direction of the pipe 2.

Then, with the radiation source 5 positioned in the longitudinal direction of the pipe 2 in this way, when the air pressure supply means is operated and air pressure is fed into the guide tube 3, the elastic member 4 a is passed through the guide tube 3. The expansion member 4a is expanded in its diameter and brought into close contact with the inner surface of the pipe 2. As a result, the radiation source 5 is positioned so as not to move in the longitudinal direction of the pipe 2 due to the friction between the outer surface of the elastic member 4a and the inner surface of the pipe 2, and the tip of the guide tube 3 connected to the elastic member 4a is positioned. 3a is positioned at the center of the pipe 2. As a result, the radiation source 5 arranged near the tip 3a of the guide tube 3 is also arranged at the center position of the pipe 2.

[0012]

[Problems to be solved by the device]

 By the way, since the positioning device 1 uses air for positioning the radiation source 5 and expands the expansion / contraction member 4a, the guide tube 3 and the expansion / contraction member 4a are connected in an airtight state, and the airtight state is maintained. Must be retained during the inspection. However, such a positioning device 1 has a disadvantage that an auxiliary facility such as an air pressure supply means for supplying air is required and a complicated structure is required to maintain airtightness. is there. Further, since the radiation source 5 is used when positioning the radiation source 5, if the film F is arranged in advance in the welded portion X, the film F is exposed during the positioning work, and a proper inspection is performed. It is difficult to do this. Further, if the film F is mounted after the radiation source 5 is positioned, it is necessary to temporarily store the radiation source 5 in the radiation source storage container 6 and then reposition the radiation source 5 after mounting. There was a problem that it could not be carried out efficiently.

The present invention has been made in view of the above circumstances, and an inspection tool such as the radiation source 5 can be accurately and easily positioned on the inspected portion X in the pipe 2 by a simple operation. An object is to provide an internal inspection tool positioning device.

[0014]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention is a device for positioning an inspection tool arranged inside a pipe on a portion to be inspected, the bendable guide tube being inserted into the pipe and disposing the inspection tool at its tip. And a plurality of centering means arranged at intervals in the longitudinal direction of the guide tube, wherein the centering means is a fixing member fixed to the guide tube, and the centering means is externally fitted to the guide tube. A sliding member arranged so as to be slidable in the longitudinal direction; a biasing means for connecting the sliding member and the fixing member to bias the sliding member with respect to the fixing member in the longitudinal direction of the guide tube; The sliding member and the fixed member are arranged at intervals in the circumferential direction, and the rolling member is brought into close contact with the inner surface of the pipe by being projected outward in the radial direction of the guide tube by the biasing means. Proposes a pipe inspection tool positioning device are.

[0015]

[Action]

 According to the in-pipe inspection tool positioning device of the present invention, when the guide tube is inserted into the pipe, the centering means attached to the guide tube moves the guide tube into the pipe at each position in the longitudinal direction of the guide tube. Place it in the center position. The sliding member that constitutes the centering means is urged by pressing the pressing means radially inward by bringing the rolling element into contact with the inner surface of the pipe and sliding it along the longitudinal direction of the guide tube. Generate a biasing force on the means. Therefore, the rolling element is pressed against the inner surface of the pipe by the urging force generated by the urging means, and the guide tube is arranged at the center position of the pipe. Then, the rolling element is rolled on the inner surface of the pipe, so that the guide tube is moved in the longitudinal direction of the pipe while the guide tube is arranged at the center position of the pipe.

[0016]

【Example】

 An embodiment of the in-pipe inspection tool positioning device according to the present invention will be described below with reference to FIGS. 1 and 3. In the present embodiment, the same reference numerals are given to the portions having the same configuration as the conventional example shown in FIGS. 4 and 5, and the description will be simplified.

The positioning device 10 of this embodiment includes a guide tube 3 that is inserted from an open end 2a of a pipe 2 to a position where a tip 3a of the pipe 2 is arranged near a welded portion (inspected portion) X to be inspected. And a centering means 11 for arranging the guide tube 3 at the center of the pipe 2 and a radiation source storage container 6 attached to the rear end of the guide tube 3 for storing a radiation source (inspection tool) 5 during transportation. And the radiation source operating means 7 for advancing and retracting the radiation source 5 along the guide tube 3 are common to the conventional example. However, the positioning device 10 of the present embodiment differs from the conventional example in that the centering means 11 has a different structure and that the tip position detecting means 8 of the guide tube 3 is not provided. There is.

In the positioning device 10 of this embodiment, as shown in FIGS. 2 and 3, the centering means 11 includes a ring-shaped fixing member 12 fixed to the outer peripheral surface of the guide tube 3 in an externally fitted state, and The fixing member 12 is provided with a sliding member 13 that can be brought into contact with and separated from the fixing member 12 in the longitudinal direction of the guide tube 3. The sliding member 13 is a ring-shaped member which is arranged in an externally fitted state on the guide tube 3 similarly to the fixed member 12, but the inner diameter of the sliding member 13 is slightly larger than that of the guide tube 3. At the same time, by disposing a plurality of balls 13a contacting the guide tube 3 on the inner surface thereof, it is possible to freely move along the longitudinal direction of the guide tube 3.

A tension coil spring 14 (biasing means) is connected between the sliding member 13 and the fixing member 12 and urges the sliding member 13 and the fixing member 12 toward each other. Is provided. Three links 15 are attached to the sliding member 13 and the fixed member 12 at equal intervals in the circumferential direction so as to be swingable in the longitudinal direction of the guide tube 3. The links 15 are arranged in such a manner that the sliding member 13 and the fixed member 12 are in phase with each other, and the tips thereof are connected so as to be rotatable relative to each other, so that the respective links are radially outward. The joint portion 16 that is bent in a convex shape is formed. A block 18 having a roller (rolling element) 17 is attached to each joint 16 so as to be swingable with the roller 17 directed radially outward. When the tension coil spring 14 is in the free state, the joints 16 are bent so that the rollers 17 are projected outward in the radial direction more than the inner diameter of the pipe to be inspected. It is designed to be placed in a different position.

The tip of the guide tube 3 is in an open state, and the radiation source 5 that is moved through the inside of the guide tube 3 can be projected from the tip opening 3a.

A method of positioning the radiation source 5 inside the welded portion X by the positioning device 10 configured as described above will be described below. First, the guide tube 3 is inserted into the pipe 2 with the radiation source 5 stored in the radiation source storage container 6. In the centering means 11 provided on the guide tube 3, the distance between the fixed member 12 and the sliding member 13 is widened against the biasing force of the tension coil spring 14 so that all of them are formed. By extending the joint portion 16 of the link 15, the block 18 provided on the joint portion 16 can be moved inward in the radial direction. As a result, the outer diameter of the centering means 11 is set smaller than the inner diameter of the pipe 2, and the centering device 11 can be inserted into the pipe 2.

Then, when the centering means 11 is inserted into the pipe 2, the roller 17 is brought into close contact with the inner surface of the pipe 2 by the urging force of the tension coil spring 14. Then, the links 15 provided at three locations in the circumferential direction of the guide tube 3 are respectively stretched to balance the forces, and the guide tube 3 at the position where the centering means 11 is attached is set to the center position of the pipe 2. Deploy. Since a plurality of centering means 11 are arranged at intervals along the longitudinal direction of the guide tube 3, by inserting each centering means 11 into the pipe 2 by the same operation as described above, Each position can be arranged at the center position of the pipe 2.

Here, according to the positioning device 10 of the present embodiment, the guide tube 3 is arranged along the center line of the pipe 2 by the plurality of centering means 11, so that the insertion length thereof is Is equal to the length. Therefore, if the pipe length up to the weld X to be inspected is measured, the position of the tip 3a can be arranged in the vicinity of the weld X only by measuring the insertion length of the guide tube 3. It will be possible.

Then, with the guide tube 3 positioned as described above, the radiation source operating means 7 is operated to send the radiation source 5 out of the radiation source storage container 6 into the guide tube 3. In this case, the delivery amount of the radiation source 5 can be calculated in advance from the pipe length in the same manner as the insertion length of the guide tube 3. Therefore, for example, by attaching a measuring means (not shown) such as an encoder to the reel of the wire 7a or its motor, the delivery amount of the radiation source 5 is measured and the radiation source 5 is placed at the optimum position for inspection. It becomes possible to arrange.

As described above, according to the positioning device 10 of the present embodiment, the inner surface of the pipe 2 is pressed by the links 15 arranged at three positions at equal intervals in the circumferential direction of the guide tube 3, and the guide is performed by the balance of the force. Since the centering means 11 for arranging the tube 3 at the center position of the pipe 2 is used, it is not necessary to adopt a conventional airtight structure, and the device can be simply configured to improve reliability. it can. Further, since the guide tube 3 is arranged along the center line of the pipe 2, by measuring the insertion length of the guide tube 3 and the delivery amount of the radiation source 5, the radiation source 5 can be accurately positioned at the welding portion X. Can be positioned. Further, when positioning the radiation source 5 in the longitudinal direction of the pipe 2, the tip position detecting means 8 such as the collimator 8a, the scintillation probe 8b and the counter 8d, etc. are not required as in the conventional case, and the apparatus can be simplified. . Moreover, since the radiation source 5 is not used for the positioning, it is possible to prevent the film F arranged on the welded portion X from being exposed during the positioning work, and to realize an appropriate inspection.

The following techniques can be adopted in the in-pipe inspection tool positioning device 10 according to the present invention. Although the tension coil spring 14 is used for the centering means 11, an arbitrary biasing means 14 should be adopted instead. As the pressing means of the centering means 11, three links 15 are arranged at equal intervals in the circumferential direction, but instead of this, two or four points where the force for pressing the inner surface of the pipe 2 can be balanced. Providing the above pressing means. Although the present invention is applied to the positioning device 10 for the radiation source 5 that is moved along the guide tube 3, instead, it is applied to the positioning device 10 such as an endoscope disposed at the tip of the guide tube 3. thing.

[0027]

[Effect of device]

 As described above in detail, the in-pipe inspection tool positioning device according to the present invention includes a bendable guide tube that is inserted into a pipe and has an inspection tool at its tip, and a plurality of flexible guide tubes arranged at intervals in the longitudinal direction. The centering means is provided, and the centering means includes a fixing member, a sliding member slidably arranged in the longitudinal direction of the guide tube, an urging means connecting them, a sliding member, and Since the rolling elements are provided at intervals in the circumferential direction of the fixing member and are projected outward in the radial direction of the guide tube by the biasing means and brought into close contact with the inner surface of the pipe, the following effects are achieved. Since each position of the guide tube is positioned at the center position of the pipe by the centering means and it is arranged along the center line of the pipe over the entire length of the guide tube, the insertion length of the guide tube can be set to the pipe to be inspected. Can match length. As a result, the positioning device can be simplified, the cost of the positioning device can be reduced, and the reliability can be improved without providing a special device for detecting the tip position of the guide tube. Since the guide tube is arranged along the center line of the pipe only by inserting the guide tube, it is possible to improve the workability of the positioning work, reduce the number of man-hours, and perform remote operation.

[Brief description of drawings]

FIG. 1 is an overall view showing an embodiment of an in-pipe inspection tool positioning device according to the present invention.

FIG. 2 is a front view showing centering means of the in-pipe inspection tool positioning device of FIG.

3 is a side view showing the centering means of FIG. 2. FIG.

FIG. 4 is an overall view showing a conventional example of an in-pipe inspection tool positioning device.

5 is a vertical sectional view showing a centering unit of the in-pipe inspection tool positioning device of FIG.

[Explanation of symbols]

 2 piping 3 guide tube 5 radiation source (inspection tool) 10 positioning device (in-pipe inspection tool positioning device) 11 centering means 12 fixing member 13 sliding member 14 tension coil spring (biasing means) 15 link 16 joint part 17 roller (rolling) Moving body) 18 block X welded part (inspected part)

Claims (1)

[Scope of utility model registration request] 1. A device for positioning an inspection tool disposed inside a pipe on a portion to be inspected, wherein the guide tube is inserted into the pipe and has the inspection tool disposed at a tip thereof, and a length of the guide tube. A plurality of centering means arranged at intervals in the direction, the centering means being fixed to the guide tube and the centering means being fitted onto the guide tube and slidable in the longitudinal direction of the guide tube. A sliding member to be disposed, a biasing means for connecting the sliding member and the fixing member to bias the sliding member in the longitudinal direction of the guide tube with respect to the fixing member, and the sliding member and the fixing member. And a rolling element which is arranged at intervals in the circumferential direction and is brought into close contact with the inner surface of the pipe by being projected outward in the radial direction of the guide tube by the biasing means. Inspection tool positioning device.