JPH04120903U - Wire rod for fluid pumping - Google Patents

Abstract

(57) [Summary] [Purpose] When installing an optical fiber cable inside a polymer tube using the pneumatic feeding method, by keeping the optical fiber cable floating inside the polymer tube, bends can be prevented in the installation route of the polymer tube. Even if there is, the insertion length of the wire rod will be significantly increased. Structure: Hair-like fibers 1 are provided on the surface of an optical fiber cable 6 for holding the optical fiber cable 6 in the center of a polymer tube 5. The hair-like fibers 1 have a minimum amount of fibers per unit area and sufficient rigidity to float the optical fiber cable. In addition, since the tip thereof is in direct contact with the polymer tube 5, the material and shape should be such that the coefficient of friction is as low as possible.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a fluid pressure wire rod that is installed in a pipe by being transferred by the pressure of the fluid. This invention relates to a fluid pressure wire rod with improved insertion length.

0002

[Conventional technology]

Generally, when installing a wire in a pre-installed pipeline, the wire is moved by the pressure of the fluid. The fluid pumping method is widely used because of its simplicity. For example, wire and When installing fiber optic cables inside polymer tubes, air pressure must be applied. The feed method is used. In this case, the fluid flow in the polymer tube used is inside the polymer tube 5, as seen in the distribution of the flow velocity vector 7 shown in FIG. The speed is highest at the center, and decreases toward the tube contact surface, and the speed decreases toward the tube contact surface. The velocity is zero at the contact surface. From this, the optical fiber cable becomes a polymer tube 5 It is considered that the best way to achieve the maximum insertion length is to always maintain the center of the

0003

[Problem that the idea aims to solve]

In conventional methods, fiber optic cables are inserted into polymer tubes to extend the insertion length. Although some care has been taken to ensure that the fiber optic cable is It is just inserted loosely into the hole. Therefore, the polymer tube installation route If there is a bend, the optical fiber cable and polymer tube will always come into contact at that part. I end up. Therefore, the fluid force on the fiber optic cable decreases rapidly and , the disadvantage is that frictional force due to contact is added, the insertion length does not increase, and the number of connection points increases. was there. In this way, the fluid pumping method has a lower insertion length than the rope traction method. Therefore, there is a strong need to improve the insertion length.

0004 The purpose of the present invention is to keep the wire rod floating in the conduit, thereby improving the conventional technology described above. This eliminates the drawbacks of wire rods and greatly increases the insertion length of the wire even if there is a bend in the conduit. The object of the present invention is to provide a novel fluid pumping wire material that can be used for fluid pumping.

[0005]

[Means to solve the problem]

The present invention provides a wire for fluid pressure transport that is transferred and installed in a pipe by the pressure of the fluid. The surface of the wire has a tip with a small contact area with the inside of the pipe and a small coefficient of friction. A holding member is provided to hold the wire in a floating state within the conduit. It is.

[0006] Examples of the wire include optical fiber cables and electric wires. Also, as a holding member , hair-like fibers or protrusions are preferable, and the outer diameter of the wire provided with these should match the inner diameter of the pipe to be used. It is desirable that it be about the same size as the diameter or smaller. It doesn't matter whether the pipeline is installed before or after it is installed. stomach.

[0007]

[Effect]

If a holding member is provided on the surface of the wire, the wire will always stay in place even if the pipe is bent. It is held floating inside. Therefore, fluid force can be effectively utilized for pumping. will be lost. In addition, the contact area between the holding member and the inside of the pipe is small, causing friction. Because it has a tip with a small coefficient, it can be smoothly pumped through the pipe with little pressure loss. It will be done. Therefore, the insertion length is significantly increased.

[0008]

【Example】

The present invention will be described below using an example in which the present invention is applied to an optical fiber cable.

[0009] In the optical fiber pneumatic feeding method, air is placed inside a pre-installed polymer tube. The optical fiber cable is installed by transferring the fiber under pressure. Optical fiber for fluid pumping installed Hair-like fibers are provided on the entire surface of the cable. The fiber axis is along the diameter of the cable. These hairy fibers make the fiber optic cable a polymer material. is held in the center of the screen. The contact friction between the hairy fibers and the inner surface of the polymer tube In addition, we took into account the reduction in It is necessary to reduce the weight as much as possible.

0010 For this reason, it has sufficient rigidity to float the optical fiber and the number of fibers per unit cross-sectional area. It is believed to be most effective to provide a minimum amount of hairy fibers with . Also Since the tips of the hairy fibers are in direct contact with the polymer tube, the coefficient of friction is kept as low as possible. It is preferable that the material and shape be such that the material is thin.

[0011] Note that hairs are present not only on the surface of the optical fiber cable but also on the inner surface of the polymer tube. It is also possible to add fibers. However, in that case, due to the action of static electricity, hair This is not preferable because the shaped fibers may become entangled with each other. Therefore, hairy fibers on one side It is better to attach an antistatic agent to one side and an antistatic agent to the other. others As mentioned above, in this example, hairy fibers are attached only to the optical fiber cable side. It is because of this.

0012 In this way, you can hold the fiber optic cable on the surface of the fiber optic cable. Polymer fibers with sufficient stiffness and low coefficient of friction to The fiber optic cable is always kept centered within the conduit, even if the tube is bent. . For this reason, fiber optic cables are subject to large velocity vectors and hairy fibers Since the fiber optic cable is transported while being held in a floating state, the fiber optic cable is not removed during transport. The surface is prevented from contacting the polymer tube and experiencing frictional resistance. Also, always Keeps the optical fiber cable in a more stable condition as it is held in the center of the conduit. Can be transported.

[0013] Therefore, the insertion length can be significantly extended.

[0014] Now, a specific example of the present invention will be explained.

[0015] First, as an optical fiber unit, as shown in Fig. 1, a 0.25 UV coated G Seven I-fiber core wires or core wires and intervening fibers 4 are converged, and a primary coating 3 is applied to the outside. The tube is coated with nylon 12 to have an outer diameter of approximately 1 mm. On top of that, a layer is applied as secondary coating 2. An optical fiber coated with approximately 0.5 mm of liquid crystal polymer material with a low conversion rate and with an outer diameter of approximately 2 mm. It was made into a cable. The liquid crystal polymer was used because the hair-like fibers become fluffy when squeezed. This is because the optical fiber is easily oriented in the longitudinal direction of the optical fiber. This is because the coefficient of linear expansion becomes extremely low and the modulus of elasticity becomes high. liquid crystal high content Specific examples of children include polyethylene terephthalate and p-hydroxybenzoic acid. There are polymers.

[0016] After coating the liquid crystal polymer material to make an optical fiber cable, the optical fiber cable is Stretch the optical fiber cable through a die that is slightly smaller than the outer diameter of the was flapped to obtain hairy fibers 1 on the entire surface. Its outer diameter is the same as the inner diameter in the polymer tube. or less. In this way, an optical fiber cable with hairy fibers as shown in Fig. produced a bull. Note that the hair fibers are not formed integrally as described above, but are formed separately. It may also be installed.

[0017] Next, as shown in FIG. 3, the optical fiber with hair fibers shown in FIG. 1 is placed inside the polymer tube 5. Insert the fiber cable 6 and let compressed dry air flow in. Then, the optical fiber The cable 6 is held in the center of the polymer tube 5 to form a large flow velocity base as shown. Because it is affected by fiber optic fibers 7, it is more effective than conventional optical fiber cables without hair fibers. It was possible to feed it for a long time, and the insertion length could be significantly extended.

[0018] By the way, the main requirements imposed on the above-mentioned hairy fibers are the following two points.

[0019] Keeping the fiber optic cable in the center of the polymer tube where the flow velocity is highest .

[0020] The optical fiber cable is placed in contact with the polymer tube where the flow velocity is zero and frictional resistance occurs. Avoid contact with bulls.

[0021] Therefore, if both of these conditions are satisfied, the retaining member of the present invention is a hair-like fiber. but not limited to. For example, in Figure 4, a protrusion is provided to receive the maximum force of the fluid. The modified example shown in FIG. 5 may also be used.

[0022] The one in FIG. 4 has a spindle-shaped protrusion on the optical fiber cable 6 at an angle of 180 degrees. Two optical fiber cables are placed facing each other at equal intervals along their longitudinal direction. The bull 6 is held at two points on the polymer tube 5.

[0023] In addition, in FIG. 6, a protrusion 9 having a substantially triangular cross section is attached to the optical fiber cable 6. Three optical fiber cables 6 are connected to the polymer tube 5 in a continuous manner along the longitudinal direction. This is to hold the point.

[0024] In this way, the protrusions 8 and 9, including the hair-like fibers mentioned above, are not disposed even if they are provided continuously. It may be provided continuously. Additionally, lubricants to reduce the coefficient of friction in liquid crystal polymer materials, e.g. For example, by mixing zinc stearate, calcium stearate, etc., or by adding It may also be applied to the surface.

[0025] As described above, according to this embodiment, the optical fiber cable has hair-like fibers or protrusions. Prevent contact between the fiber optic cable and the polymer tube by attaching objects. This can significantly reduce frictional resistance. Hair-like fibers or protrusions may also be washed away. Use your body's strength to hold the fiber optic cable where the flow velocity is high. In particular, hairy fibers When the outer diameter of the fiber or protrusion is about the same as the inner diameter of the polymer tube, The cable is held where the flow velocity is highest. At that time, the optical fiber cable The insertion length is dramatically improved.

[0026] Therefore, it is now possible to pump longer optical fiber cables into the tube than before. This makes the pressure-feeding work more efficient and rational. Also, the connection point of the optical fiber cable is It has the advantage of requiring less space. Therefore, the optical transmission characteristics of optical fiber cables are also good. It is economical and economical.

[0027] In addition, the presence of hairy fibers or protrusions may cause vibrations within the tube itself and from the outside. Optical fiber cables, which are especially vulnerable to these, are not directly exposed to the mechanical effects of As a result, optical transmission characteristics and mechanical characteristics are stabilized, and reliability is improved.

[0028] Note that optical fibers are not limited to GI fibers, but can also include single mode fibers. Of course, it is possible to use a hard-wired fiber, and there are no restrictions on the type or number of fibers. Ma In addition, although we have explained using a polymer tube as an example of a conduit, the dimensions and material of the conduit, and the optical fiber The dimensions, weight, etc. of the bar cable are not limited, and various combinations can be applied.

[0029] Furthermore, even if the fluid to be pumped is a gas other than air, the wire may be an optical fiber. Liquid may be used as long as it is liquid resistant and is not a cable.

[0030]

[Effect of the idea]

According to the present invention, a holding member is provided on the surface of the wire so that the wire is suspended in the conduit. Even if there are bends in the conduit installation route, there will always be a large Because it can receive flow velocity, the insertion length of the wire can be significantly increased. .

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of an optical fiber cable according to an embodiment of the present invention, which has a holding member on its surface.

FIG. 2 is an explanatory diagram showing velocity vectors of fluid within a polymer tube.

FIG. 3 is an explanatory diagram showing the velocity vector of a fluid when an optical fiber cable is contained in a polymer tube.

FIG. 4 is a side view and a sectional view of an optical fiber cable showing a first modification.

FIG. 5 is a side view and a sectional view of an optical fiber cable showing a second modification.

[Explanation of symbols]

1 Hairy fiber 2 Secondary coating 3 Primary coating 4 Optical fiber core wire or core wire and intervening material 5 Polymer tube 6 Optical fiber cable 7 Flow velocity vector 8 Protrusions 9 Protrusions

──────────────────────────────────────────────── ─── Continuation of front page (72) Creator Takemitsu Hanami Hitachi, 5-1-1 Hidakacho, Hitachi City, Ibaraki Prefecture Inside Hidaka Factory of Electric Cable Co., Ltd.

Claims (1)

[Scope of utility model registration request] 1. A fluid pressure-feeding wire that is installed in a pipe by being transferred by the pressure of the fluid, wherein the wire has a tip portion on the surface thereof that has a small contact area with the inside of the pipe and has a small coefficient of friction. A wire rod for fluid pressure feeding, characterized in that a holding member is provided to hold the wire rod in a floating state within a conduit.