JPH0754651B2 - Tether cable - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a tether cable having a non-metallic tensile strength element wire, and more particularly, to a state of the tensile strength element wire that easily transmits X-rays. It is possible to inspect by a line.

[Problems to be Solved by Prior Art and Invention] The use of X-rays for nondestructive inspection of power cables, etc.
It is widely used (Japanese Patent Laid-Open No. 2-19752, etc.).

However, for example, for the tether cable of FIG.
When trying to perform a line inspection, the following points become problems.

In FIG. 2, 12 is a power cable core for power, 14 is its conductor, 16 is an insulator, and 18 is a common sheath.

A tensile strength element wire 20 is made of a non-metal such as FRP and is twisted on the sheath 18 into, for example, two layers.

Reference numeral 22 is a sheath, and 24 is an outer sheath, which is made of a rubber mold or the like.

Where the tensile strength element wire is passed through the outer thick outer sheath 24.
In order to perform 20 X-ray examinations, it is necessary to use X-rays having a considerable penetrating power, and since such X-rays easily penetrate the tensile strength element wires, it is almost impossible to obtain the image. is there.

On the contrary, if soft X-ray is used, the outer thick outer sheath 24
It is absorbed by and the internal tensile element wire is not reflected.

[Means for Solving the Problem] As illustrated in FIG. 1, a gap between the wires 20 of the outermost layer of the twisted layers of the tensile strength element wires 20 (V generated between adjacent wires) over the entire length of the cable. A material 30 containing a contrast agent is filled in a groove-like valley) and attached to the strand 20.

[Operation] When the material 30 containing the modeling agent is filled in the gap between the outermost strands 20 of the twisted layer of the tensile strength element wire 20 over the entire length of the cable and adhered to the wire 20, the X-ray When irradiated, the non-metallic tensile strength element wire 20 itself is barely visible, but the material 30 containing the modeling agent is clearly projected, and the striped pattern (strands of the material containing the modeling agent are twisted together. (Corresponding to the valley) appears.

Then, when the tensile strength element wire 20 is sound, the striped image is also continuous, but when an abnormality such as buckling occurs, it becomes discontinuous or deforms.

That is, even if a non-metallic tensile strength element wire that originally permeates and cannot be projected, its state can be indirectly known from the image of the material containing the contrast agent.

Further, since the contrast medium is not directly mixed with the tensile strength element wire itself, its performance is not impaired.

[Embodiment] FIG. 1 is an example in which the present invention is applied to a tether cable having the same structure as in FIG.

Reference numeral 30 denotes a material containing a contrast agent, which is a material in which a known contrast agent (a substance having a large X-ray absorbing power such as barium sulfate or lead oxide) is mixed with soft rubber or the like.

The material 30 containing the contrast agent is filled in the gaps between the outermost strands 20 (V-grooves formed between adjacent strands).
It is attached to the wire 20.

By using the material 30 in which the contrast agent is mixed with rubber or the like, it is possible to give the ability to follow the movement of the tensile strength element wire 20 without hindering the movement thereof.

Further, the resolution can be adjusted by changing the mixing ratio of the contrast agent.

The structure other than the parts described above is the same as in the case of FIG.

The X-ray used for the inspection is strong enough to penetrate the thick outer sheath 24.

The tensile strength element wire 20 itself is not visible, but the material 30 containing the contrast agent
Is projected and appears as a striped pattern as described above.

As described above, when the tensile strength element wire 20 is sound, this gap portion (striped pattern) is also continuous, but when an abnormality such as buckling occurs, this gap becomes discontinuous.

As a result, deformation, buckling, breakage, etc. of the tensile strength element wire 20 can be easily observed and inspected.

[Advantages of the Invention] (1) Since a material containing a contrast agent is filled in the gap between the outermost strands of the twisted layers of the strength member strands over the entire length of the cable, and the material is attached to the strands. As described above, when X-ray irradiation is performed, the non-metallic tensile strength element wire itself is not imaged, but the material containing the contrast agent is imaged and appears as a striped image. When the image is generated, the striped image is discontinuous or deformed.

Therefore, by utilizing this phenomenon, the X-ray inspection of the non-metallic tensile strength element wire which is originally transparent and cannot be projected becomes possible.

(2) Since the contrast agent is not mixed directly into the member inside the cable, the performance as a cable is not impaired.

[Brief description of drawings]

 FIG. 1 is an explanatory diagram of an embodiment of the present invention, and FIG. 2 is an explanatory diagram of a conventional technique. 12: Power cable 14: Cable conductor 16: Cable insulator 18, 22: Sheath 20: Tensile strength element wire 24: Outer sheath 30: Material containing contrast agent

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Noro Kadomo 5-6-4 Tsukiji, Chuo-ku, Tokyo Mitsui Engineering & Ships Co., Ltd. (72) Inventor Masahiro Shinozaki 1-5-1 Kiba, Koto-ku, Tokyo No. Fujikura Electric Line Co., Ltd. (72) Inventor Tetsuya Kamijo 1-5-1, Kiba, Koto-ku, Tokyo Fujikura Electric Line Co., Ltd. (72) Inventor Hiroyuki Kuriyama 1-1-5, Kiba, Koto-ku, Tokyo Fujikura (56) References JP-A-52-27576 (JP, A) JP-A-2-91506 (JP, A) JP-A 62-14011 (JP, A) Actual development 61-104308 ( JP, U)

Claims (1)

[Claims] 1. A tether cable having a twisted layer of non-metallic tensile strength element wires inside an outer sheath made of non-metal, wherein the outermost strand of the twisted tensile strength element wires is provided over the entire length of the cable. A tether cable, characterized in that a material containing a contrast agent is filled in a gap between the filaments and adhered to the strand.