JPH0334694Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a flaw detection device for existing conduits, in which a flaw detection sensor for the pipe is attached to a main body that is movable within the pipe using a pulling tool or a pressing tool.

[Prior art]

Conventionally, as shown in, for example, Japanese Utility Model Application Publication No. 55-13266, the structure of the main body was complicated, had a large resistance to fluid transport, and was difficult to bend and deform.

[Problem that the invention attempts to solve]

However, the complicated structure of the main body is disadvantageous in terms of cost and repair, and the large resistance to fluid transport necessitates interrupting fluid transport during flaw detection. It cannot be applied to conduits and has low practical value as a flaw detection device for existing conduits.

The purpose of the present invention is to improve the main body structure so that it is simple, has low resistance to fluid transport, and is easy to bend and deform.

[Means to solve the problem]

The characteristic configuration of the present invention is that a main body that is equipped with a flaw detection sensor and can be moved freely within a pipe, a pair of front and rear holders, a flexible object that connects the holders, and
consisting of a number of elastic strips attached to the holder and arranged around the flexible object,
One end of each of the elastic band-like bodies is fixed to one side of the holding body, and the other end is inserted into a recess formed in the other side of the holding body so that the length can be changed freely, and each of the elastic band-like bodies is This is due to the fact that the tube is curved so that it protrudes in the radial direction toward the middle in the longitudinal direction.
Its effects are as follows.

[Effect]

In other words, the pair of holders, one flexible object, and a suitable number of elastic bands that form the main body are all simple in shape and inexpensive, and the structure is simply a combination of these components. Therefore, the main body structure can be made extremely inexpensive compared to the conventional one.

Then, curved elastic band-shaped bodies are arranged circumferentially, and the intermediate side in the longitudinal direction of the elastic band-shaped bodies protruding in the radial direction of the pipe is brought into contact with the inner surface of the existing conduit, so that flaw detection can be carried out on the inner surface of the existing conduit. Since the position of the sensor can be set, the outer diameter of the holder and flexible body should be sufficiently smaller than the inner diameter of the existing conduit, and the gaps between the elastic strips should provide sufficient resistance to fluid transport. Can be made small,
It is possible to continue fluid transport even during flaw detection.

Furthermore, when passing through a sharp bend in an existing conduit, since all of the elastic bands are fixed to only one side of the holder, both the elastic bands and the flexible object are not easily resisted by the other. The main body is easily and sufficiently deformed with almost no distortion, and the entire body is sufficiently deflected and deformed along the bend, allowing smooth passage through the bend.

[Effect of idea]

As a result, it has become possible to easily and successfully perform flaw detection in existing conduits, even while fluid transport continues, and even in the presence of sharp bends, using equipment that is advantageous from an economical and repair perspective. For example, maintenance work on city gas pipes, water pipes, etc. can now be carried out advantageously in terms of economy, workability, fluid supply, etc.

〔Example〕 Next, an example will be shown with reference to FIGS. 1 and 2.

A plurality of overcurrent type, ultrasonic type, etc. Appropriate flaw detection sensors B are installed in a line in the pipe circumferential direction to form a flaw detection device that can detect flaws in the entire existing conduit P as it moves within the pipe.

To form the main body A, a pair of front and rear holders 2 are used.
Connect a and 2b with a coil spring 3,
The brushes 4a and 4b that support the coil spring 3 substantially concentrically with the existing conduit P are held by the holders 2a and 2b.
The coil spring 3
They are arranged at appropriate intervals around the . elastic band-like body 5,
6, one end 5a, 6a of each is fixed to one side 2a or 2b of the holder, and the other end 5b, 6b is inserted into a recess 7 formed in the other 2b or 2a of the holder, so that the length can be changed freely. In addition, in both of the holders 2a and 2b, the elastic band 5 or 6 fixed to the holder 2a or 2b, and the elastic band 6 or 5 inserted into the holder 2a or 2b, They are arranged alternately in the circumferential direction of the holder.

Each of the elastic strips 5 and 6 is curved so that it protrudes in the tube radial direction toward the middle in the longitudinal direction, and the ends 5a,
5b or 6a, 6b are formed in a narrow shape so that deformation of the elastic band-like bodies 5, 6 due to changes in diameter or bending of the tube is performed smoothly, and longitudinally intermediate portions 5c, 6c are formed.
The structure is such that the contact state with the tube is maintained.

Fitting the elastic support 8 to the coil spring 3,
A flaw detection sensor B is arranged between the longitudinal intermediate portions 5c and 6c of the elastic strips 5 and 6 and the elastic strip 8,
The flaw detection sensor B is attached to the outer elastic band 5,
6 and is configured to maintain a state of proximity to the inner surface of the existing conduit P, thereby improving flaw detection accuracy. Flaw detection sensor B
A lead wire 9 from the pipe is connected to a suitable flaw detector outside the existing conduit P through a pulling tool or a pressing tool 1.

[Another example]

Next, another embodiment will be described.

When forming the main body A, the shape, material, etc. can be changed as appropriate. For example, holding body 2
The shapes of a, 2b and the elastic strips 5, 6 can be changed, or the brushes 4a, 4b and the elastic strips 8 can be omitted. Furthermore, the fixing structure of the elastic strips 5, 6 may be changed; for example, all the elastic strips 5, 6 may be fixed to one of the holders 2a or 2b. Further, to connect the holders 2a and 2b, for example, a wire or a chain may be provided instead of the coil spring 3, and in short, it is sufficient that the holders 2a and 2b are connected by the flexible object 3.

The flaw detection sensor B can be appropriately selected in terms of type, arrangement, information collection means, etc., and for example, the flaw detection sensor B may be embedded in the longitudinally intermediate portions 5c and 6c of the elastic strip 5.6.

In addition, sensors other than those for flaw detection, such as those for visual inspection, may also be provided.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an embodiment of the present invention;
The figure is a sectional view taken along the line -- in FIG. 1. A...Body, B...Flaw detection sensor, 2a, 2
b...Holding body, 3...Flexible object, 5, 6...Elastic band-shaped body, 5a, 5b, 6a, 6b...End of elastic band-shaped body, 5c, 6c...Longitudinal middle of elastic band-shaped body Part, 7... recessed part.

Claims (1)

[Scope of Claim for Utility Model Registration] A flaw detection device for existing conduits, in which a sensor B for flaw detection on the pipe is attached to a main body A that is movable within the pipe using a pulling tool or a pressing tool, the main body A
However, a pair of front and rear holders 2a, 2b, a flexible object 3 connecting the holders 2a, 2b,
It also consists of a large number of elastic strips 5, 6 attached to the holder 2a or 2b and arranged around the flexible object 3, with one end 5a, 6A of each of the elastic strips 5, 6 attached to the holder 2a or 2b. It is fixed to one side 2a or 2b of the holding body, and the other end 5
b, 6b are inserted into a recess 7 formed in the other 2b or 2a of the holding body and are arranged so as to be freely variable in length, and each of the elastic band-like bodies 5, 6 protrudes toward the center in the longitudinal direction in the radial direction of the tube. A flaw detection device for existing conduits with a curved shape. Each of the elastic strips 5 and 6 has a shape in which both ends 5a and 5b or 6a and 6b are thinner than longitudinal intermediate portions 5c and 6c, which are disposed so as to be integrally displaceable near the outside with respect to the flaw detection sensor B. A flaw detection device according to claim 1 of the utility model registration claim formed in .