JPH0668008U - Connection of metal tube with plastic coated filament - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a connecting portion of a metal tube containing a plastic-coated filamentous body having excellent airtightness. [Structure] Two plastic-coated filaments 1-containing metal tubes 2 are connected to each other, and the two metal tubes 2 on the outer periphery thereof are covered with a sleeve 3 to be connected,
The sleeve 3 is crimped to each of the predetermined positions of the two metal pipes 2 and crimped, and both ends of the sleeve 3 are connected to each other.
Metallic tube 2 with plastic-coated filament 1 hermetically welded to
At the connection part of the above, the self-fusing protective tape 5 and the sub-stretchable protective tape 6 were successively wound tightly on the sleeve 3 including the periphery of the airtight welded portion 4. [Effect] Since the sleeve 3 and its airtight welded portion 4 are reinforced by sequentially winding the self-welding protective tape 5 and the sub-hard stretchable protective tape 6 tightly, the airtightness is maintained even when an external force is applied. It is not damaged and water infiltration is prevented.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a connecting portion of a metal tube containing a plastic-coated filament having excellent airtightness.

[0002]

[Prior art]

 The metal tube containing a plastic-coated filament is a plastic-coated metal core or a plastic-coated optical fiber core, etc., housed in a metal tube of SUS, iron, Al, or the like. This metal tube with a plastic coated filament is wrapped around the outside of the water supply pipe or power cable together with the exterior wire to enable water supply and power transmission and control of control equipment at the same time. And is used. By the way, when connecting metal pipes with plastic-coated filaments of this type, after connecting the internal filaments, the outer metal tubes are welded or cold welded, or the flanges at the end of the metal tube are bolted. It was done by a method such as tightening. However, all of the above connection methods are insufficient in strength with respect to tension and twist applied during installation. In addition, the welding method has a problem that the plastic-coated filament is thermally damaged, and the flange method cannot obtain the required airtightness.

Under these circumstances, a sleeve type connection part was developed (actual Kaihei 3-96605). As shown in the longitudinal sectional view in FIG. 2, this sleeve-type connecting portion connects the plastic-coated filaments 1 of the two metal tubes 2 containing the plastic-coated filaments 1, A sleeve 3 is laid over the end portions of the two metal pipes 2 on the outer circumference, and the sleeve 3 is crimped and crimped to each predetermined position of the two metal pipes 2, and the end portions of the sleeve 3 are made of metal. The tube 2 was airtightly welded, and the sleeve 3 was covered with a heat-shrinkable tube 6 so as to cover the sleeve 3.

[0004]

However, the above-mentioned sleeve-type connection portion is thicker than the other portions by the amount of the sleeve covering the connection portion, and therefore, the connection portion is manufactured, manufactured, transported, or laid on the seabed. At times, the floor, ground and seabed rub against each other, and external force is applied to the connection more than other parts.As a result, the weld is damaged and the internal airtightness is impaired, and seawater enters the metal pipe. There was a problem.

[0005]

[Means for Solving the Problems]

 The present invention provides a connecting portion for a metal tube containing a plastic-coated filament, which solves the above-mentioned problems, and has the structure of a metal tube containing two plastic-coated filaments. Connect them together, cover the two metal pipes on the outer periphery with sleeves, and then crimp the sleeves to the respective predetermined locations of the two metal pipes and crimp them, and further attach both ends of the sleeves to the metal pipes. At the connection part of the metal tube containing the airtightly welded plastic-coated filament, a self-bonding protective tape and a sub-stretchable protective tape are wound tightly in sequence on the sleeve including the periphery of the airtight welded part. And

In the present invention, the reason why the self-fusing protective tape is wound first and then the sub-hardenable stretchable protective tape is wound on the self-fusing protective tape is This is because the self-bonding property is assisted by tightening the tape with the sex protection tape from the top, and the waterproof effect is more reliably realized. The two kinds of protective tape are wound tightly so that the periphery of the airtight weld between the sleeve and the metal tube is completely covered. The number of windings is arbitrary such as single layer, double layer or multiple layers depending on the application. In the case of single winding, it is preferable that the periphery of the welded portion is wound particularly thickly. If a heat-shrinkable tube is further covered on the wound body of the two types of protective tape, the strength and waterproof effect are improved. For the self-bonding protective tape, a tape material containing butyl rubber or isobutylene as a main component is used. A tape material containing polyethylene, polypropylene, or the like as a main component is used as the sub-stretchable protective tape. By covering the above-mentioned both protective tapes with a heat-shrinkable tube, the connecting portion can be further strengthened and waterproofed. When a double tape in which a self-bonding protective tape and a sub-stretchable protective tape are stacked is used, the winding work is efficiently performed.

[0007]

[Action]

 The connecting portion of the metal tube containing the plastic-coated filament of the present invention covers the ends of the two metal tubes to which the plastic-coated filament is connected by spanning the sleeves to cover the metal tube and the sleeve. After tightly integrating them, both ends of the sleeve are airtightly welded to the metal pipe, and then the self-bonding protective tape and the sub-stretchable protective tape are wound tightly in sequence on the sleeve including the periphery of the airtight welded portion. Since the airtight weld is reinforced, damage to the airtight weld due to external stress is prevented. Even if the airtight welded part is damaged, the airtightness is maintained because the outer periphery of the airtight welded part is covered with the self-welding protective tape and the sub-stretchable protective tape.

[0008]

【Example】

 Hereinafter, the present invention will be described in detail with reference to examples. Embodiment 1 FIGS. 1A and 1B are longitudinal sectional explanatory views showing an embodiment of a connecting portion of the present invention. The connection part shown in Fig. 1 is made by cutting and removing a predetermined length of the metal pipe 2 at the end of the two SUS metal pipes (outer diameter 8 mmφ, inner diameter 3 mmφ) 2 containing the plastic-coated optical fiber core wire 1. The inner plastic-coated optical fiber core wire 1 is exposed, the exposed plastic-coated optical fiber core wires 1 are connected to each other, then the sleeve 3 is put on the ends of the two metal tubes 2 and the sleeve 3 is replaced with two sleeves 3. Crimping and crimping to each predetermined position of the metal pipe 2 of the above, and the sleeve 3 and the metal pipe 2 are airtightly welded at both ends of the sleeve 3, and further, on the sleeve 3, including the periphery of the airtight welded portion 4. , A butyl rubber self-fusing protective tape 5 is wound, a polyethylene sub-refractory stretchable protective tape 6 is wound around it, and a heat-shrinkable tube 7 is further covered on it to form a connection part. Was formed.

Comparative Example 1 In Example 1, the connection part of the metal tube 2 containing the plastic-coated optical fiber core wire 1 was formed by the same method as in Example 1 except that the sleeve 3 was directly covered with the heat-shrinkable tube 7. Formed.

Ten connecting parts of the metal tube 2 containing the above-mentioned two kinds of plastic-coated optical fiber core wires 1 are prepared respectively, and after applying a series of external stresses of bending, twisting, impact, and ironing to each of them. Then, the connection part was placed under water pressure, and the presence or absence of water ingress into the metal tube 2 was examined. As a result, no water was observed in the joints of the present invention, but water was observed in the three comparative example products. When the water-immersed comparative product was examined, cracks were found at the welded portions.

Example 2 A connection portion was formed by the same method as in Example 1 except that the airtight welding between the metal tube 2 and the sleeve 3 was not performed in Example 1. Comparative Example 2 The connection portion was formed by the same method as in Example 2 except that the sub-stretch resistant protective tape 6 was not wound. Comparative Example 3 The connection part was formed by the same method as in Example 2 except that the self-fusing protective tape 5 and the sub-slightly elastic protective tape 6 were not wound in Example 2. After applying a series of stresses of bending, twisting, impact, and ironing to each of the above-mentioned connecting parts, they were placed under water pressure and examined for the presence or absence of water infiltration into the metal pipe. The results are shown in Table 1.

[0012]

[Table 1]

As is clear from Table 1, the product of the present invention (No. 1) was scarcely flooded. From this, it was demonstrated that the product of the present invention can prevent water infiltration by the wound two kinds of protective tape even if the airtight weld is damaged. On the other hand, No. 2 of the comparative example product did not wind the sub-refractory stretchable protective tape, so that the self-fusing protective tape could not sufficiently achieve self-fusing and the inundation failure rate increased to 30%. It was In No. 3, neither self-bonding protective tape nor sub-stretchable elastic protective tape was wound, and the heat-shrinkable tube was directly covered on the sleeve, so the waterproofing effect was low, and the inundation failure rate increased to 50%.

[0014]

【effect】

 As described above, in the connection part of the metal tube containing the plastic-coated filamentous body of the present invention, the sleeve of the connection part and the periphery of the airtight welded part are covered with the self-bonding protective tape and the sub-stretchable protective tape in order. Since it is reinforced by being wound around, airtightness is maintained even when external force is applied, accidents such as flooding are prevented, and a remarkable industrial effect is achieved.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an embodiment of a connecting portion of a metal tube containing a plastic-coated filament of the present invention.

FIG. 2 is a vertical sectional view of a connecting portion of a conventional metal tube containing a plastic-coated filament.

[Explanation of symbols]

 1 Plastic coated filament 2 Metal tube 3 Sleeve 4 Airtight weld 5 Self-bonding protective tape 6 Sub-expandable elastic protective tape 7 Heat shrink tube

Claims (1)

[Scope of utility model registration request] 1. A metal pipe containing two plastic-coated filaments, wherein the plastic-coated filaments are connected to each other, and the two metal pipes on the outer periphery thereof are covered with a sleeve to be connected to each other, and two sleeves are provided. At the connection portion of the metal tube containing the plastic-coated filament, which is crimped to each predetermined position of the metal tube and crimped, and further, both ends of the sleeve are hermetically welded to the metal tube,
A connection part of a metal tube containing a plastic-coated filament, wherein a self-bonding protective tape and a sub-stretchable protective tape are wound tightly in order on a sleeve including the periphery of the airtight weld.