JP2801334B2 - In-pipe communication method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a cable or light to be newly laid in a conduit in which a power line such as a cable, an optical fiber, and a communication line such as a flexible tube are already provided. The present invention relates to an in-pipe wiring method in which a new body, such as a fiber or a flexible tube, is inserted through the striated body as a guide and passed.

(Prior art) Conventionally, when nothing is laid in a pipeline, a laying body such as an FRP rod or a carbon rod is connected to a laying body such as a power line or a communication line, and the striated body is used as a guide. The laid body was passed through the pipe by inserting it through the opening of the passage and passing it.

Also, in the same manner as described above, even when a power line, a communication line, and the like are already installed in the pipeline, a new body to be newly laid on a wire body such as an FRP rod or a carbon rod is connected,
The new body was passed through the conduit by inserting the same striated body through the conduit opening as a guide.

(Problems to be Solved by the Invention) However, when an existing body is laid in a pipeline, if a conventional linear body is inserted, the same linear body does not move in the middle of the pipeline, and a new one is installed. I could not pass through my body.

(Object of the Invention) It is an object of the present invention to provide an in-pipe line connection method that allows a new body to be easily passed through a pipe in which an existing body is laid.

(Means for Solving the Problems) The inventors of the present application have conducted intensive studies to solve the above-mentioned problems, and found that when the striated body is inserted, the striated body is connected to the existing part of the pipe at the curved portion of the pipe. Have been found to bite or fit into the gap between the striated body and the striated body.

Furthermore, the inventors of the present application have also found that this biting phenomenon occurs for the following reasons.

That is, as shown in FIG.
(Pressing force) F that presses the wire into the pipe 2 acts as a force (pressing force) F ₀ that presses the filament 3 out of the bend of the pipe 2. As shown in FIG. 4, when the striated body 1 and the existing body 3 come into contact with each other, the pressing force F ₀ is a force (tangential force) F ₁ that tends to slide in the tangential direction, and the pressing force F ₀ is pressed in the normal direction. force (drag) is divided into two component forces and F _2. Of these, the tangential force F ₁ is the clearance between the pipe 2 and the existing body 1 as shown in FIG.
If it is directed in the narrow direction of 11, the same linear body 3 will bite into the gap 11.

On the other hand, the existing body 1 is not always located at the lowest part of the pipe line 2 and may be at a position slightly shifted from the lowest part, for example, as shown in FIG. Center A of this existing body 1
The angle formed by a straight line connecting the line and the center O of the pipeline 2 to a perpendicular passing through the center O of the pipeline 2 is defined as θ. Incidentally, the displacement as described above is caused by the balance of the component force in the tangential direction between the existing body 1 and the pipeline 2 between the tension F _C of the existing body 1 and its own weight W as shown in FIG. And they are shown as follows:

_{F C cosθ = W | sinθ |} ∴ | sinθ | / cosθ = F C / W Well, for the tangential force F ₁ is not suitable for a narrow direction of said gap 11, at least the center B of the striatum 3 existing It must be at the same height or higher than the center A of the body 1. Then, as shown in FIG. 5, the maximum outer diameter a of the striated body 3 is calculated as follows with the case where the center B of the striated body 3 is at the same height as the center A of the existing body 1 as a boundary point. Here, as shown in Fig. 5, the inner diameter of the pipe: D ₀ , the outer diameter of the existing body: D ₁ , the distance between the center of the striatum and the center of the existing body: AB, the center of the pipe and the center of the striatum Distance to center: OB, Horizontal component of same distance OB: A'B, Distance between pipeline center and center of existing body: OA, Horizontal component of same distance OA: AA ', Vertical component of same distance OA: OA ′, OB = 1/2 (D ₀ −a), AB = 1/2 (D ₁ + a), OA = 1/2 (D ₀ −D ₁ ), AA ′ = | sinθ | · OA OA ′ = cos θ · OA, and according to Pythagorean theorem, OB ² = OA ^{′ 2} + A′B ² = OA ^{′ 2} + AB + AA ′) ² = (cos θ · OA) ² + (AB + | sin θ | · OA) ² = Cos ² θ · OA ² + AB ² + 2 | sin θ | AB · OA + sin ² θ · OA ² = (cos ² θ + sin ² θ) · OA ² + 2 · | sin θ | · AB · OA + AB ² cos ² θ + sin ² θ = Since OB ² = OA ² +2 | sin θ | AB · OA + AB ² ∴OB ² −OA ² = 2 | sin θ | AB · OA + AB ² where the left side of the equation is the left side = ｛1/2 (D ₀ −a)｝ ² − ｛1/2 (D ⁰ −D ₁ )｝ ² = 1/4 [D ₀ ² −2a · D ₀ −a ² −D ₀ ² + 2D ₁ · D ₀ −D ₁ ² ] = _{1/4 [-2a · D 0 + 2D} 1 · D 0 + a 2 -D 1 2] the same expression on the right is the right side = 2 · | sinθ | · { 1/2 (D 0 -D 1)} · {1 _{/ 2 (D 1 + a)} } + {1/2 (D 1 + a)} 2 = 1/4 [2 · | sinθ | · (D 0 -D 1) · (D 1 + a) + (D 1 + a) ^{2] = 1/4 [2} · | sinθ | · (D 0 · D 1 -D 1 2 + a · D 0 -a · D 1) + (D 1 2 + 2a · D 1 · a 2)] Therefore both sides 4 times to _{-2a · D 0 + 2D 1 ·} D 0 + a 2 -D 1 2 = 2 · | sinθ | · (D 0 · D 1 -D 1 2 -a · D 0 -a · D 1) + D 1 _{^{2 + 2a · D 1 + a}} 2 ∴-a · D 0 + D 1 · D 0 = | sinθ | · (D 0 · D 1 -D 1 2 + a · D 0 -a · D 1) -a · D 1 + D 1 _{^{2 ∴-a · D 0 +}} D 1 · D 0 = D 1 · | sinθ | · (D 0 -D 1) + a · | sinθ | · (D 0 -D 1) + a · D 1 + D 1 2 -a · D ₀ −a · D ₁ −a · | sinθ | · (D ₀ −D _{1) = D 1 · | sinθ} | · (D 0 -D 1) -D 1 · D 0 + D 1 2 a · (D 0 + D 1) + a · | sinθ | · (D 0 -D 1) = D 1・ (D ₀ −D ₁ ) −D ₁・ (D ₀ −D ₁ ) ・ | sin θ | ∴a ・ {(D ₀ + D ₁ ) + | sin θ | ・ (D ₀ −D ₁ )} = D ₁・(D ₀ −D ₁ ) (1− | sin θ |) ∴a = {D ₁ · (D ₀ −D ₁ ) (1− | sin θ |)} / ｛(D ₀ + D ₁ ) + | sin θ | · ( D ₀ −D ₁ )｝ At least the maximum outer diameter a of the striated body 3 needs to be larger than this.

The maximum value of the gap 11 as shown in Figure 8, so is D ₀ -D _1, the maximum outer diameter a of the striatum 3 is required to be a <D ₀ -D _1.

As described above, according to the in-line construction method of the present invention, the wire body 3 in which a new body such as a cable or an optical fiber is connected is installed in the pipeline 2 on which the existing body 1 such as a cable or an optical fiber is laid. Is used as a guide in the in-pipe wiring method in which a new wire is inserted, characterized by using a filament 3 whose maximum outer diameter a satisfies the following conditional expression.

{D ₁ (D ₀ −D ₁ ) (1− | sin θ |)} / {(D ₀ + D ₁ ) + | sin θ | (D ₀ −D ₁ )} ≦ a <(D ₀ −D ₁ )… , A: maximum outer diameter of the linear body 3 D ₀ : inner diameter of the pipe 2 D ₁ : outer diameter of the existing body 1 θ: a straight line connecting the center O of the pipe 2 and the center A of the existing body 1 is the pipe 2 To the perpendicular passing through the center O of
90 ° <θ <90 ° (operation) In the in-pipe wiring method according to the present invention, the maximum outer diameter a of the filament 3 used is a conditional expression, that is, {D ₁ (D ₀ −D ₁ ) (1 - | sinθ |)} / { (D 0 + D 1) + | sinθ | ( since _{D 0 -D 1)} ≦ a} <(D 0- D 1) ... in the range of the line as in the Figure 6 Since the center B of the strip 3 is at least as high as or above the center A of the existing body 1, the tangential force of the pressing force F ₀ acting on the strip 3 is applied.
F ₁ does not face the narrow direction of the gap 11 between the existing body 1 and the pipeline 2. Therefore, even if the striated body 3 is pushed into the pipeline 2, the striated body 3 does not bite into the gap 11 and does not move.

Note that when the existing body 1 is at the lowest part of the pipeline 2 as shown in FIG. 9, the above θ = 0 °, and the above conditional expression is expressed as {D ₁ (D ₀ −D ₁ ) (1- | sin0 | _{)} / {(D 0 +} D 1) + | sin0 | (D 0 -D 1)} ≦ a <(D 0- D 1) ∴ {D 1 (D 0 -D 1)} / (D 0 + D 1 ) ≦ a <(D ₀ −D ₁ )... ′, Where a: the outer diameter of the filament 3 D ₀ : the inner diameter of the pipe 2 D ₁ : the outer diameter of the existing body 1 It can be seen that the case is implied.

(Example) As an example of the present invention, various striated bodies 3 were inserted and penetrated into a pipeline 2 as shown in FIG. 10 in which a power cable having an outer diameter of 65 mm was laid as an existing body 1. . This line 2
Is made of a steel pipe having an inner diameter of 125 mmφ, and has a curved portion 10 having a curvature of 5 m which is bent at right angles at three places as shown in FIG. At this time, no tension was applied to the existing body (power cable) 1 in the pipeline 2 and the existing body 1 was located at the lowest part of the pipeline 2 as shown in FIG. .

Therefore, in the present invention, the conditional expression {D ₁ (D ₀ −D ₁ ) (1− | sin θ |)} / {(D ₀ + D ₁ ) + | sin θ | (D ₀ −D ₁ )} ≦ a <(D _By substituting D ₀ = 125 mm, D ₁ = 65 mm, and θ = 0 ° into ₀ −D ₁ ), the condition 20.5 mmφ ≦ a <60 mmφ was obtained.

As Example 1 of the present invention, a FRP pipe having a maximum outer diameter a = 25 mmφ and an inner diameter d ₀ = 3 mmφ as shown in FIG.

As shown in FIG. 2, a large-diameter portion 21 having a maximum outer diameter a = 22 mmφ is formed at appropriate intervals l (2 m in this embodiment) as shown in FIG. 7mmφ,
An FRP filament 3 having an inner diameter d ₀ = 3 mmφ was used.

When these are inserted into the pipeline 2 from the direction of the arrow z in FIG. 10, the filament 3 of the first embodiment can smoothly pass through the pipeline 2 and is connected to the filament 3. The new body was newly laid in the pipeline 2.

On the contrary, the maximum outer diameter a = 3.5 m as a comparative example of the present invention.
When a rod made of FRP having a diameter of mφ was used as a striatum and was inserted into the pipe line 2 in the same manner as described above, a point B in FIG.
Has stopped working.

Also, the striated body 3 of the second embodiment can smoothly pass through the inside of the pipe line 2 similarly to the striated body 3 of the first embodiment, and a new body connected to the striated body 3 is piped. Newly laid in Road 2.

As is apparent from this result, if the large-diameter portion 21 having the maximum outer diameter a satisfying the above-mentioned conditional expression is formed at an appropriate position in the longitudinal direction of the filament 3 as shown in FIG. Road 2
Biting of the striated body 3 into the gap 11 between the wire and the existing body 1 is prevented, and the friction between the three members does not increase. More preferably, the large diameter portion 21 is inserted when the wire 3 is inserted or when a new body is inserted.
However, the large-diameter portion 21 is always
Should be formed.

(Effects of the Invention) As described above, according to the inside line 2 construction method of the present invention, since the maximum outer diameter a of the striated body 3 satisfies the conditional expression, the existing body 1 and the line 2 The new linear body can be easily passed through the pipe line 2 without the same linear body 3 being bitten or fitted into the gap 11, so that the same linear body 3 cannot be pushed further. Become.

[Brief description of the drawings]

FIGS. 1 and 2 are side views showing various examples of a striated body used in the in-pipe communication method according to the present invention, FIG. 3 is an explanatory view of a curved portion of the pipe, and FIGS. FIG. 9 is a sectional view taken along line AA of FIG.
FIG. 4 is an explanatory view of a state in which the striatum bites into the gap between the existing body and the pipeline, FIG. 5 is an explanatory view of a boundary point where the striatum does not bite into the gap, and FIG. FIG. 7 is an explanatory view of a state in which the striatum does not bite into the gap, FIG. 7 is an explanatory view of a state in which the existing body is displaced from the lowest part of the pipeline, and FIG. 8 is a maximum condition of the maximum outer diameter of the striatum FIG. 9 is an explanatory diagram showing a state where the existing body is at the lowest part of the pipeline, and FIG. 10 is an overall explanatory diagram of the pipeline used in the embodiment of the present invention. 1 is the existing body 2 is the pipeline 3 is the striated body Conditional expression a is the maximum outer diameter of the striated body D ₀ is the inner diameter of the pipe D ₁ is the outer diameter of the existing body θ is the center of the pipe and the existing body Angle formed by a straight line connecting the centers with respect to a perpendicular passing through the center of the pipeline

Claims (1)

(57) [Claims] 1. A pipe through which a new body, such as a cable or an optical fiber, is inserted into a pipeline 2 in which an existing body 1, such as a cable or an optical fiber, is laid, using the striated body 3 as a guide. An in-road line construction method, wherein a wire body 3 having a maximum outer diameter a that satisfies the following conditional expression is used. {D ₁ (D ₀ −D ₁ ) (1− | sin θ |)} / {(D ₀ + D ₁ ) + | sin θ | (D ₀ −D ₁ )} ≦ a <(D ₀ −D ₁ ) Where, a: maximum outer diameter of the filament 3 D ₀ : inner diameter of the pipe 2 D ₁ : outer diameter of the existing pipe 1 θ: a straight line connecting the center O of the pipe 2 and the center A of the existing pipe 1 is a pipe Angle with respect to a vertical line passing through the center O of -2, -90 ° <θ
<90 ゜