RU2245567C1 - Method for laying fiber bundle in subsurface plastic pipes - Google Patents

Abstract

FIELD: subsurface laying and wiring of fiber bundles in plastic pipes using pneumatic method.

SUBSTANCE: each section of fiber bundle disposed beyond pipeline is placed in plastic pipe whose outer diameter is smaller than that of pipeline, the latter is tightly joined through adapter to plastic pipe, plastic pipes are tightly joined with pipe connections of dead-end box made in sealed cast-iron protective casing, and fiber bundles are connected within this box. Plastic pipes holding fiber bundles are coiled in turns at permissible bending radius so as to ensure that dead-end box occurs inside one coil formed at the same time from turns of two plastic pipes or between two coils, each being formed from turns of one plastic pipe. Butt-ends of pipelines, plastic pipes holding fiber bundles, and dead-end box are placed in fiberglass shell tied to pipelines to protect them from rodents.

EFFECT: enhanced reliability and service life of fiber-optic lines using light-mass fiber bundles laid in subsurface plastic pipes.

3 cl, 4 dwg

Description

The invention relates to the field of underground laying of cable communications, and in particular to a technology for mounting optical fiber couplers laid in underground plastic pipes by a pneumatic method.

A known method of building fiber-optic communication lines (FOCL) in plastic pipelines (1, 2), which consists in the fact that initially one of the known methods (cable layer or in a pre-prepared trench) laid plastic pipelines having a coating on their inner walls, reducing friction of the stretched optical cable. Then, the construction lengths of the plastic pipelines are connected using plastic couplings, and optical pipelines with long building lengths (2-4 km) are laid pneumatically (using compressed air supplied from the compressor) into these pipelines. At the ends of the construction lengths of plastic pipelines with an optical cable (OK) blown into them, containers of optical couplings are installed, into which plastic pipelines are inserted through the inlet pipes together with OK and dead ends are mounted at the ends of the OK, which, together with the turns of the technological stock of OK, are laid in containers . The containers are closed with lids and filled with soil.

The disadvantage of this method is that the containers of optical couplings having a meter diameter have a large area of expulsion from frozen soil. To prevent this phenomenon in the pits, sand and gravel pads are added to install containers. Nevertheless, in the real conditions of the Russian climate, especially in the spring (February - April), when there are frosts at night and thaws during the day, as a result of large temperature jumps, the containers of optical couplings “stick out” from the soil, while the containers are depressurized in places the location of the inlet pipes and are filled with water, while all the initial advantages of this method of constructing fiber-optic communication lines are accordingly lost and after 2-3 years there is a real probability of damage to the turns of the technological stock OK alleviated in the container, and OK couplings, which are containers without protective metal covers. Thus, the known method does not guarantee the reliable operation of the fiber optic link in case of cyclic changes in temperature.

The technical result of the invention is to increase the reliability and service life of fiber-optic communication lines with lightweight OK, which are laid in underground plastic pipelines.

The specified technical result is achieved by the fact that in the method of connecting optical cables laid in underground plastic pipelines, which consists in splicing optical cables in a dead end sleeve, a plastic pipe having an outer diameter smaller than the outer diameter is put on each piece of the optical cable located outside the pipeline pipelines, hermetically connect the pipeline using an adapter with a plastic pipe, hermetically connect plastic pipes with nozzles of a dead-end coupling, placed in a hermetic protective cast-iron casing, in which optical cables are spliced, while plastic pipes with optical cables laid in them are laid in turns with an acceptable bending radius so that the dead-end sleeve is inside one bay, simultaneously formed from turns of two plastic pipes, or between two bays, each of which is formed from turns of one plastic pipe, while for protection against rodents they have pipe ends, plastic pipes with optical cables and a dead end UFT in a shell made of fiberglass, which is tied to pipelines.

In particular cases of the proposed method:

- to check the tightness of the pipeline before installing the shell made of fiberglass from the adapter, a tight outlet of the tube is performed for placing the pipelines under excessive gas pressure with control of its stability by an air pressure gauge;

- prior to installation of the sheath made of fiberglass from the coupling, the hermetically sealed copper wire is connected, connected to the armor of the optical cable or the aluminum-polyethylene sheath of the optical cable, which is connected to the ground electrode and / or to instrumentation to check the integrity of the optical cable.

The invention is illustrated in figure 1-figure 4.

Figure 1 shows a coil of spiral-shaped coils of pipes with OK and a dead-end coupling in a cast-iron protective casing located inside the bay.

Figure 2 shows two bays of spiral turns of pipes with OK and a dead-end coupling in a cast-iron protective casing, located between the turns of pipes with OK.

Figure 3 shows the layout of the coupling relative to the ground.

Figure 4 shows the fastening of the shell of fiberglass to pipelines.

The method is implemented as follows.

After installing the segments of building lengths OK 1 in plastic, for example polyethylene, pipelines 2 by blowing or pulling on the segments OK 1 located outside the pipelines 2, put on the segments of plastic pipes 3, the length of which corresponds to the length of the technological stock OK, while the outer diameter of the plastic pipes 3 is smaller than the outer diameter of pipelines 2. For example, pipeline 2 has an outer diameter of 32/27 mm, and pipes 3 have an outer diameter of 25/21 mm.

Then, each plastic pipe 2 is hermetically connected using an adapter 4 (for example, using a “SPUR” adapter sleeve with a right-hand external thread on one end and a left-hand thread on the other) with a corresponding plastic pipe 3. Plastic pipes 3 are tightly connected to the dead end pipes couplings 5, which are made in sealed protective cast-iron casings, in which the segments of the optical cables are connected 1. After connecting the OK in the coupling 5, the plastic pipes 3 with the optical cables laid in them 1 they are coiled with a permissible bending radius into a bay 6 or a bay 7, while a dead-end coupling 5 is placed inside one bay 6 formed simultaneously from the turns of two plastic pipes 3 (see Fig. 1), or between two bays 7, each of which is formed from the turns of one plastic pipe 3 (see figure 2). Bays 6 and 7 contain technological stock OK 1.

To check the tightness of the pipe 2 from the adapter 4, it is possible to carry out a hermetic output of the pipe 8 for placing the pipe 2 under excessive gas pressure with control of its stability by an air pressure gauge (not shown).

From the coupling 5, it is possible to carry out a sealed output of the sealed copper wire 9 from the armor OK 1 or the aluminum-polyethylene sheath OK 1, which is connected to the ground electrode (not shown) and / or control equipment (not shown) to check the integrity of OK1.

To protect OK from rodents, the ends of the pipelines 2, adapters 4, plastic pipes 3 with an optical cable 1 and a dead-end sleeve 5 in a closed shell 10 made of fiberglass, which are tied to the pipelines 2, are placed.

After installing the shell made of fiberglass, the foundation pit is filled with soil.

The proposed connection method OK allows to increase the reliability and service life of underground fiber optic links, because in case of occurrence of buoyancy forces during permafrost, the blind coupling 5, made in a hermetic cast-iron protective casing, will be pushed into the upper layers of the soil, rising like a float from the center of the laid turns of a bay 6 of plastic pipes 3 with OK 1 or between bays 7 of turns of plastic pipes 3 with OK 1, while this does not cause serious pulling forces applied to the plastic tubes located in the nozzles, and to the OK inside the coupling, which ensures stable tightness of the proposed connection node at a temperature urnyh races.

Sources of information:

1. Application WO / 22470, cl. G 02 B 6/44, published 04/30/2000.

2. V.M. Akishin, E.E. Ass, V.V. Vinogradov, B.D. Noskov, “Laying of fiber-optic cables for railway communication in plastic pipelines”, “Avtomatika” magazine, 1998, No. 3.

Claims (3)

1. The method of connecting optical cables laid in underground pipelines, which consists in connecting optical cables in a dead end sleeve, characterized in that a plastic pipe having an outer diameter smaller than the outer diameter of the pipeline is sealed on each piece of the optical cable located outside the pipeline they connect the pipeline using an adapter with a plastic pipe, hermetically connect the plastic pipes to the nozzles of the blind coupling, made in a hermetic protective cast-iron casing, in where optical cables are spliced, while plastic pipes with optical cables laid in them are laid in turns with an allowable bending radius so that the dead-end sleeve is inside one bay, simultaneously formed from turns of two plastic pipes, or between two bays, each of which is formed from turns one plastic pipe, at the same time, pipe ends, plastic pipes with an optical cable and a dead-end sleeve in a fiberglass sheath that is tied to protect against rodents m to pipelines. 2. The method according to claim 1, characterized in that to check the tightness of the pipeline before installing the shell made of fiberglass from the adapter, a tight outlet of the tube is performed for placing the pipelines under excessive gas pressure with control of its stability by an air pressure gauge. 3. The method according to claim 1, characterized in that prior to installing the sheath made of fiberglass from the sleeve, the hermetically sealed copper wire connected to the armor of the optical cable or the aluminum-polyethylene sheath of the optical cable is connected, which is connected to the ground electrode and / or to instrumentation for checking the integrity of the optical cable.

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