New technologies for installation of local communication cables. Laying a communication cable in the ground

A separate document has been issued on the laying of communication cables. Collection concerning the topic. At first glance, it seems that the rules for laying communication cables contradict the definitions. As you get acquainted, you begin to understand: the type of track is decisive. According to these aspects, a brand is selected that determines the methods of installation on the ground. Let's see how the communication cable is laid.

Cabling

Contrasting with power grids, communication cable is often underground. The right of way is traditionally used. The cable runs along roads, underground, along poles. Priority is given to highways of greater significance. If there is a choice to use a federal highway or a local one, the first one is used. The line length must be minimal. In some cases, it is allowed to lay communication cables in the ground by smoothing sharp corners, straight between separate sections highway. Only in the conditions of Siberia, Far East, Far North, getting access to the Internet in a private house, residents are forced to categorically deviate from the rules.

The road network is not developed everywhere. They lead lines through undeveloped terrain. It is allowed to lay the cable on the taps railways. Making sure the connection is on different sides canvases with a high-voltage line. If not feasible, the power track runs closer to the railroad tracks. Finally, many are interested in what is meant by the term road diversion. The area starting behind the ditch, reserve (lies behind the berm).

Cable bays

Bookmarking, if possible, is carried out in a trenchless way. We saw how the majors steppes old cable pull the Urals, then rent and share? Bookmarking is a similar method, only in the opposite direction. A decent-sized bulldozer is working, carrying a coil of communication cable. With the help of a special harrow, the vein lies immediately underground. After the technique, a more or less even seam remains. The use of mechanized labor during laying is strictly regulated. Let's look at VSN 116 on this matter (a separate normative act, RM 13-2):

1. The volume of earthworks performed by machinery is at least 80%.
2. Cable laying is 87% mechanized.
3. Pulling the line in the cable duct - at least 65%.

We consider the presence of regeneration points to be a distinctive feature of communication lines. The weakened signal is amplified again, reaching the standard level. Otherwise, laying is not possible. optical cable communications over long distances. The modem will simply be unable to recognize the signal. To optimize the network, special measures are taken, the cable for laying the communication line is taken of the appropriate brand. Allowing to reduce losses by reducing the number of trace regenerators. Let's discuss what are the lines of communication, composition.

Communication cable

General organization of communication lines

Cable communication lines are usually divided:

• Trunk, usually laid between the nodes of the first class (large settlements of neighboring regions).
• Intrazonal, lying within one relatively small region (region).
• Trunk connecting capacities are not inferior to the first category, they will serve as a kind of bridge between larger segments.
• Local cable networks are laid within one city (laying a communication cable to a private house).

Inside the city, the network (called the backbone internal) reaches the indoor closet. Distribution board for the area. If you take telephone lines, a dozen houses can have a steel cabinet, inside there is a wiring for buildings. Each building is equipped with another shield of a more modest size. The areas between houses are called distribution areas. At the entrance there is a subscriber wiring. Not a cable, a usual cord, a wire from two copper veins.

According to the signal of the chain, it is customary to divide:

• Lines of the first class I with voltage over 360 volts.
• Lines of the second class II with voltage up to 360 volts.
• Subscriber lines, the voltage varies 15 - 30 volts.

Laying, installation of communication cables is carried out:

1. Directly in the ground.
2. In different underground utilities, underground.
3. Underwater.
4. Mounted.

Little different from power grids. According to the classification of the scale of the line (first table), recommendations are given for laying lines with a fixed grade. There are two types of cables - electrical and optical.

Electrical cables

Consist of the usual copper wires. Aluminum bonding is rarely used due to high losses.

1. The main (primary) lines are formed by a coaxial cable in aluminum sheaths KMA-4, in lead - KM-8/6 (only for reconstruction), coaxial small-sized aluminum - KMTA-4.
2. Connecting main lines are built with similar products, with the exception of those provided with a lead sheath. Sometimes it is allowed to use ISS 4x4 communication cables.
3. On intrazonal networks, MKT-4, VKAP, MKS-4x4x1.2, ZK-1x4x1.2 are used.
4. Local networks (primary and secondary) are built from: MKS-4x4x1.2 and 7x4x1.2, KSP, KSPZ, BKSPZ, T, TP, PRPPM.
5. Wired broadcasting networks (radio common use, used by the USSR) is built on PRPPM, MRMP, RBPZEP, RBPZEPB, RMPZEP, RMPZEPB. The last four grades belong to the hydrophobic filled family. This includes products containing both aluminum and copper inclusions. When wet, the process of electrochemical corrosion begins.

Optical cables

They are formed by glass filaments that propagate waves close to the visible spectrum. High frequencies will allow you to efficiently encode a large amount of information. There are single- and two-mode conductors.

1. Backbone networks are built from single-mode cables with a different number of cores (4, 8 or 16). At wavelengths of 1.3 and 1.55 µm.
2. Intrazonal networks are based on the use of multimode gradient fibers of 4 or 8 pieces in a bundle. The working wavelength is 1.3 µm.
3. Local networks differ from intrazonal networks by the assumption of the use of a wave of 0.85 microns.

unfashionable fashion

In practice, it is necessary to reduce the regeneration interval. As a result, more amplifiers would have to be installed on the highways. Sometimes unacceptable, expensive. Methods for laying communication cables under water cause many difficulties. They told how the Anglo-French concern Alcatel lays an optical cable under the ocean floor. Loading the ship takes three weeks, now imagine how long underwater installation takes.

The signal amplifier-regenerator weighs half a ton. While the cable goes along the route, things move quickly, then it stops, because the cores need to be cut into the case. Regenerator failure is a problem. The less it costs on the main line, the better. It is profitable to make a profit for the route laid, there is no benefit from repairs. Therefore, single-mode fibers must be used on the backbone.

The laying of a communication cable in the ground is carried out so that the regenerators are located in a flood-free area. Exceptions to the rules are allowed with justification of the technical side of the issue. Landslide, mudflow places are not used. To provide signal amplifiers with energy, the communication cable is laid in a special way:

1. On intrazonal networks, existing points are used to the maximum. Equipped with ready-made energy sources.
2. For local networks installation of associated equipment is allowed. Priority is given to equipped nodes. Everyone sees a key example in the entrance. Provider junction box containing amplifying equipment. Power is taken from the local power grid.

Laying a communication cable in the ground

The laying method is determined by the brand of cable, discussed in the sixth section of VSN 116. PRPPM is used by second class II lines with their own sewerage, on subscriber lines - in the ground with rare exceptions. Depending on the type of line, the depth of laying the communication cable in the ground varies:

1. Electrical and optical cables of the primary network of any level outside settlements, class II lines and connecting lines lie at a depth of 1.2 meters.
2. Other intrazonal networks are laid 0.9 meters underground.
3. Electric cables of urban, rural telephone networks in the territory of settlements are buried by 0.7 meters, outside - 0.8. Smaller values ​​\u200b\u200bare used - they use protection from bricks (slabs). Similar to the one used to equip the power lines (see the corresponding review).
4. 0.8 meters is used by Class II broadcast cables.

You should know: soils are divided into groups, the requirements listed above apply to categories I - IV. The fifth includes permafrost, rocks: the depth of laying the communication cable decreases (0.4 - 0.6 meters, the depth of the trench is 10 cm more). VSN 600 contains a lot of thematic information. The width of trenches (developed by mechanized method) is indicated.

The slopes of the line crawls like a snake, the deviation to the side is 1.5 meters (the length of the linear sections is 5 meters). It is customary to use special armor cable brands. By air, it is allowed to lay subscriber, intrazonal networks with a technical justification. In the second case, existing columns are used. The laying of the communication cable in the building is carried out in accordance with the usual standards. Provides protection against induced interference.

We hope that we have conveyed to readers the main ways of laying communication cables. Line locations are often marked with signs. Commanding Kazakhs know the excavation sites, the signs act as warning signs. The installation organization will draw up a project so as not to touch neighboring lines. And special warning signs are called to help to make on the ground.

Copper cable installation technology

YES. Popov, Chief Specialist of the Communications Department of the GTSS

The organization of telecommunication networks based on fiber-optic transmission lines has overshadowed the problems associated with the construction, installation and operation of copper cable lines. One of the most "sore" issues for copper-core cables with polyethylene or metal sheaths is the tightness of the sheath and control of its integrity during installation and operation.

Based on the experience of designing, building and operating the GTSS in 1986, he proposed a cable installation technology with the separation of the "trunk" of the main cable from the branch cables into relay cabinets and service facilities located on the stage using gas-tight insulating sleeves. At the same time, a decision was made to ground the armor and sheaths of trunk cables according to a three-point scheme - only at the inputs to the terminal (amplifying) points and in the middle of the amplifying section.

This solved a number of problems:

Electrically isolate the main cable from the branch cables, which eliminated the ingress of reverse traction current through the branch into the main cable;

To control the resistance between the armor and the “ground”, the armor and the shell and the shell and the “ground” in the amplifying section;

Put under control the integrity of the hose protective covers of cables with an outer cover of the Shp type;

Reduce the search time for leaks in the main cable sheath;

Reduce the cost and complexity of construction, since there is no need to ground the armor and cable sheath at each coupling.

The technology of installation of the main cable is described in detail in the typical design materials “Cable lines for long-distance communication of railway transport. Linear structures, 410405-
TMP, ShP-43-04”, developed in 2004. However, today new problems have arisen. One of them is organizational: escebists and signalmen operate lines for various purposes, and the requirements for the parameters of these lines are different. Whereas before, high-frequency, low-frequency communication circuits, as well as automation and telemechanics were combined in one trunk cable.

The second problem is that there are no fully developed cable installation technologies, and the process of their implementation is slow.

Consider the state of technology used for the installation of communication cables. VNIIAS developed the "Instructions for the installation, repair and restoration of railway cable lines using new technologies and materials", which was approved in 2002. We note some of its features. The first is the absence in the instructions of previously existing technologies for mounting couplings by soldering and explosion welding. The second is a change in the design of the splitter coupling: instead of the traditional T-shaped, we have a glove configuration. The third one is the use of “Armoplast” tape instead of cast-iron couplings for protection against mechanical influences. Fourth - the possibility of mounting direct sleeves when restoring the tightness of the sheath without cutting the cable using heat-shrinkable cuffs.

In the presence of positive factors, there are also some costs in new technologies and materials for installation. Thus, the mortise tee coupling “disappeared” from the range of couplings, in which the connection of the conductors of the branch cable with the main cable was carried out in parallel without cutting the conductors of the latter.

Let us analyze a new technology for the installation of gas-tight insulating sleeves. According to paragraph 8.2 of the instructions for the installation of gas-tight insulating sleeves GMVI-4, GMVI-7, GMVI-40, a 4 or 6 m long section is used on the branch cables (hereinafter, the stub cable). In its middle, protective covers are removed - an aluminum sheath and belt insulation, and with the help of a collapsible removable form installed in place of the removed sheath of the cable section (without cutting the current-conducting cores), a polyurethane composition is poured. When mounting the sleeve with cutting the cable, after pouring the assembled splice, parts of the MPP brand sleeves and a heat-shrinkable tube HERE are pushed onto its ends. Thus, a branch is created without the use of GMVI.

When laying the cable in the subgrade body, the recommended branch length is 6 m. However, with a 4 m stabilizing cable, an additional coupling is required. If the segment of the stabile cable representing the GMVI coupling is soldered from one end into a branching coupling, the other end must be extended with a cable of a certain length in order to enter the relay cabinet or an object located on the stage.

A decision arises: the length of the branch cable should be such that it overlaps the distance from the installation site of the tee (branch) coupling to the box installed at the facility where the branch cable is inserted. In this case, the installation of the GMVI - the cut and removal of the sheath of the branch cable and the filling of this place with a polyurethane composition are carried out directly on the branch cable in one pit with a splitter. This eliminates the need for an additional coupling.

Gas-tight couplings GMS-4, GMS-7, GMSM-40, manufactured according to classical scheme for cable installation technologies by hot soldering, produced by OJSC Svyazstroydetal. Their transformation into gas-tight insulating sleeves is carried out in accordance with the instructions by removing a strip 10 mm wide from the middle of the gas-tight sleeve and restoring its tightness by slipping onto the remote section of the heat-shrinkable tube.

Thus, based on the analysis of new technologies for the installation, repair and restoration of railway cable lines and the available design experience, it is advisable to recommend the following:

The installation of gas-tight insulating sleeves should be carried out directly on the branch cable in the same pit with a branch sleeve and refuse to standardize the length of the branch cables according to the instructions (stub cables). Similarly, it is necessary to install a gas-tight coupling directly on the main cable when it is entered into amplifying (terminal) points;

Supplement the instructions with a list of standard sets of consumables (sets for mounting various brands of cables) and tools that must be purchased for the manufacture of gas-tight couplings and which must be provided for in the design.

INSTALLATION OF AUTOMATION AND TELEMECHANICS CABLES

No less questions arise regarding the technology of installing signaling cables. Today, these are independent cable lines that are laid both at stations and on hauls to organize automation and telemechanics circuits. Below we will talk about cable lines for the organization of signaling circuits on hauls.

The fundamental difference between signaling and communication cable lines is that automation and telemechanics circuits are organized, as a rule, in physical pairs, the frequency parameters of which are not standardized. Specialists may object, referring to the fact that cables in pairs are recommended for use. However, this objection is not justified, since there are no norms for the installed sections of signaling cable lines. It should be noted that in section 22 of the Rules for laying and installing cables of signaling devices, PR 32 TsSh 10.01-95, only norms of insulation resistance of cable cores are established before installation, after installation and during operation.

The second difference is the construction length of the cables. It is no more than 300 m for cables with polyethylene insulation in a plastic sheath (GOST R51312-99) and for cables with polyethylene insulation in a metal sheath with hydrophobic filling (TU 16.K71-297-2000). For cables with polyethylene insulation with water-blocking compounds in a plastic sheath, manufactured according to TU 16.K71-353-2005, the construction length is: for unarmoured - 1000 m, armored with the number of pairs up to 14 - 800 m, with the number of pairs 16 or more - 600 m.

Currently, the current regulatory documents for the installation of signaling cables are: "Rules for laying and installing cables of signaling devices, PR 32 TsSh 10.01-95"; "Rules for the installation of cables for signaling and interlocking with hydrophobic filling, M. 1995"; “Rules for the installation of cables for signaling and interlocking with aluminum sheaths and hydrophobic filling. PR 32 TsSh 10.11-2001.

A significant difference of the technology is also that the signaling cable lines are not kept under excessive pressure, they have a large range of connecting and branching couplings (floor, underground) and, as a result, different technologies for splicing construction lengths. In addition, they do not have branches and are introduced into service facilities and relay cabinets with a full cut, and due to short building lengths, a large number of couplings are mounted on the route.

Of the connecting underground couplings recommended in the regulatory documents, the signal-blocking dead-end (MSBT) and straight for signal-blocking cables (MSB-A (u) b) are most often purchased, designed for cables, respectively, with polyethylene and aluminum sheaths. They are supplied as cable mounting kits. The manufacturer, OJSC Svyazstroydetal, has developed appropriate instructions for their installation.

Technologies for connecting cables in underground direct couplings using frames and heat-shrinkable tubes, as well as a polyurethane composition, are fixed in the "Rules for the installation of cables for signaling and interlocking with hydrophobic filling", but sets of consumables are not provided. At the same time, such kits are given in the "Rules for the installation of cables for signaling and interlocking with aluminum sheaths and hydrophobic filling PR 32 TsSh 10.112001".

Heat-shrinkable tubes and cuffs, as a rule, of foreign manufacturers are used. However, heat-shrinkable cuffs are not recommended for use by regulatory documents for the installation of signaling cables.

FEATURES AND CONTRADICTIONS IN THE TECHNOLOGY OF INSTALLATION OF COMMUNICATION CABLES AND STsB

The fundamental differences between communication cables and signaling cables, in addition to being kept under excessive pressure, installation of inputs and branches, are also found in the device for grounding armor and metal sheaths and in the standards of grounding devices, as well as the standards of induced voltages in cable cores on electrified AC railways.

The circumstance that forces us to analyze and evaluate the state of technology and installation of signaling cables is their length, as well as the presence of galvanically non-separated circuits in them (from station to station), which are subject to electromagnetic influences of AC electric traction.

This should be taken into account when choosing routes and brands of cables, as well as calculating the effect of the traction network of electrified AC railways on the signaling lines.

In these calculations, it is necessary to take into account the requirements of regulatory documents for the installation of cables and, first of all, recommendations on the arrangement of grounding of their armor and sheath, subject to electromagnetic influences that affect the protective action coefficient of the sheath and the magnitude of the induced voltage in the conductors of the signaling cables.

Institute "Giprotranssignalsvyaz" on the basis of regulatory documents developed and released in 2003. auxiliary materials"Calculation of the influence of the traction network of electrified AC railways on the signal lines, 650219", which guide the designers.

The norms of induced voltages in the conductors of cables of the signaling system are adopted in accordance with " Guidelines on the design of automation, telemechanics and communication devices. Issue 37 contact network electrified AC railway. They are: for the forced mode of operation of the contact network - 250 V, for the short circuit mode - 1000 V.

The value of the induced voltage for the forced operation of the contact network is confirmed in the "Norms process design devices of automation and telemechanics in the federal railway transport, NTP STsB/MPS-99", and for the short circuit mode it is indicated that the permissible voltage in the relay circuits is regulated by the "Rules for the protection of communication devices and wire broadcasting from the influence of the traction network of electrified AC railways" . However, in Table 3.2 of these rules, only the norm of the allowable induced voltage with respect to earth in the cable cores is given, when special protection and safety measures are applied, and it is 0.6 uisp - the test voltage of the insulation of the cores or input equipment with respect to earth ( shell) specified in technical conditions or in GOST.
For signaling cables manufactured in accordance with GOST R51312-99 and TU 16.K71-297-2000, the norm of the test voltage between the conductors is 2500 V. Taking this norm to calculate the short circuit mode, taking into account the norm for the allowable induced voltage, we get: 0.6 x x2500 = 1500 V, i.e. we have conflicting standards for calculation in the short circuit mode.

For communication cables, the grounding of the armor and sheath is carried out according to a three-point scheme. In this case, the armor and the shell are not soldered at the inputs and in the couplings. The main cable is electrically insulated by gas-tight insulating sleeves against taps. The sheath and armor of the branch cables are grounded to a separate ground when entering the relay cabinet or an object on the run. The resistance of grounding devices in electrified sections for terminal amplifying points and combined buildings of communication centers with EC posts, according to Table 7.1 of the "Departmental norms for the technological design of telecommunications in railway transport, VNTP / MPS-91", as a rule, should be 4 Ohm. For signaling cables in NTP STsB/MPS-99 specific rule for grounding devices is not available.

The rules for laying and installing cables of signaling devices - PR 32 TsSh 10.01-95 interpret the grounding device for armor and sheaths of signaling cables both on lines and at inputs differently than for communication cables. So, in clause 21.2 of these rules it is said that in areas equipped with electric traction of both alternating and direct current, metal sheaths and armor of cables in relay cabinets and service buildings should be connected with wire segments of the PV2, PV3 or PV4 brand with a cross section of 2 .5 mm2. In clause 21.3, an explanation is given that in underground couplings, the armor and cable sheaths are connected by separate insulated wires PV grades, i.e., they are not connected to each other and are not grounded.

In addition, paragraph 21.4 says that in areas with DC electric traction, the wires connecting the armor and cable sheath in service buildings and in relay cabinets are connected by a common wire through the instrumentation to a protective grounding device, and in areas with AC electric traction the common wire is connected directly to the grounding device.

Clause 21.16 indicates that on armored signaling and blocking cables with or without metal sheaths, after entering the service and technical building (post Etz, GAC, etc.), it is necessary to arrange insulating sleeves. However, the design, installation technology of these insulating sleeves and the norms of grounding devices for input cables are not given. In addition, paragraph 21.11 states that for grounding the armor and cable sheaths at relay cabinets, transformer boxes, branching, universal and connecting couplings, standard signal grounding devices should be installed, the resistance of each of which should not exceed 10 Ohm.

Taking into account the absence of decisions on the design of the insulating sleeve, the SCSC developed and issued a local document - order No. 31 dated November 30, 2000, which prescribes cables with a metal sheath or armor to be cut on UPM or RM type ground sleeves and put into the EC- TM cable brand SBPZU.

Thus, it turns out that there is no clarity on the rationing of resistance and the installation of grounding devices for grounding the sheaths and armor of signaling cables in service buildings.

Signaling cable lines have armor and sheath integrity only from the EC post to the signal point (relay cabinet), then from the signal point to the next signal point, etc. At the same time, check the resistance in armored cables with metal sheaths of the "armor - ground" sections, "armor - shell" and "shell - ground" throughout the line from station to station is impossible (instrumentation is recommended only in areas with DC electric traction, but armor and shell are connected to the grounding device soldered together).

Based on the foregoing, the following conclusions can be drawn:

It is necessary to correct the mentioned normative documents on the laying and installation of signaling cables in terms of determining a clear range of used couplings and kits for mounting couplings on signaling cables;

Do not solder the armor and sheath at the inputs to relay cabinets, EC post buildings, service facilities by analogy with communication cables, grounding them (armor and sheath) element by element through the instrumentation, and give a clearer version of Section 21 PR 32 TsSh 10.01-95. Specify and legitimize the installation of insulating sleeves on armored cables and cables with metal sheaths, which will make it possible to control the integrity of the hose cover, and for armored cables to control the resistance between armor and "ground", armor and sheath and sheath and "ground" in the sections of the post EC - signal point and further from signal point to signal point;

To normalize the grounding resistance of the armor and sheath of cables when they are entered into service and technical buildings and objects on the stage, based on the installation scheme of the main cables of the signaling system (full section of the cable and its entry into the relay cabinet, object on the stage);

To ensure the integrity of the armored cover and metal sheath when cutting the cable in cabinets at the terminals, which will make it possible to maintain its coefficient of protective action throughout the entire length from station to station.

PERSPECTIVES

Many problems of laying and installation of communication cables and signaling systems should have a unified approach to their solution, and it is advisable to resolve the accumulated issues promptly.

As a first step in this direction, it would be necessary to consider these problems at a meeting of specialists, develop and agree on a program to eliminate them, develop norms, rules, recommendations, technologies and approve them for use in the design, construction and operation of cable communication lines and signaling systems. Moreover, first of all, it is necessary to normalize the parameters of lines and circuits of automation and telemechanics, establish the norms of induced voltage in the cores of the signaling cables to calculate the effect of the traction network of electrified AC railways on the signaling lines, the norms for grounding the armor and cable sheath and work out a clear technology for grounding the armor and cable sheaths.

In signaling systems, microprocessor and other electronic devices are currently used and they cannot be subject to the current standards of induced voltage, as well as grounding arranged for equipment installed in buildings.

The second issue is the regulation of the types of couplings used for the installation of communication cables and automation and telemechanics. I would like to refer to an article published in Vestnik Svyaz No. 3, 2003 by S.M. Kuleshov, "Popular delusions of linemen". The author gives an overview of the current state of affairs in the application of technologies and sleeves for cable installation and emphasizes that electric and optical cables can and should be supplied with sleeves that consumers will mount on communication lines.

The third question is to eliminate all contradictions and omissions regarding the installation of signaling cables, which are available in PR 32 TsSh 10.01-95.

Fourth - to give the "green light" to cables with water-blocking compounds, ensuring their implementation on the road network with support and competent use of technologies and materials for mounting couplings on them. These cables include main high-frequency communication cables with three-layer film-porous insulation and water-blocking materials (TU 16.K71.358-2005), cables for signaling and interlocking with polyethylene insulation with water-blocking materials in aluminum (TU 16 .K71.354-2005) and plastic (TU 16.K71.353-2005) shells. They are devoid of many of the shortcomings inherent in classic cables, and will be able to provide higher operating parameters lines.

The junction of the cable installation is called the clutch. The inclusion of a cable in terminal devices is called charging. The following requirements apply to cable solder joints: The ohmic resistance of the cores must not increase. The soldering point should not be too thick compared to the cable diameter.

If this work does not suit you, there is a list of similar works at the bottom of the page. You can also use the search button

LECTURE 11, 12, 13. INSTALLATION OF COMMUNICATION CABLES

General requirements to the installation of communication cables.

Separate construction lengths, sections, spans of laid cables are spliced, connected in one line and included in terminal devices. The junction (mounting) of the cable is called the clutch. The inclusion of a cable in terminal devices is called charging.

Installation is a responsible job in the construction of cable structures. High quality installation ensures the reliability of the cable line.

The following requirements apply to cable splices:

1. The ohmic resistance of the wires must not increase.
2. The insulation resistance must not decrease.
3. Pairs and lays must be maintained. Breaking pairs and mixing them up is not allowed.
4. Reliable mechanical strength of the connection must be ensured at the splice site.
5. Screen continuity (if any) should be restored.
6. The sealing of the shell must be strong and tight.
7. The soldering point should not be too thick compared to the cable diameter.

When splicing cables, you must:

1. Splice the cores with each other in the same order as they are in the corresponding layers of the cable.
2. Connect the control groups of one end of the cable to the control groups of the other.
3. Connect cores with insulation of the same color to each other.

Before and after installation, the quality of the cable is monitored. The finally assembled line is subjected to control electrical measurements.

Mounting materials, tools and fixtures.

Checking cables before installation.

Installation of urban telephone cables.

Cutting cable ends for installation

The ends of the cable are laid in the well and fixed on the consoles so that the end of one cable overlaps the end of the other to the required length, which is determined by the capacity of the cable and the diameter of the cores.

Annular cuts are made at the place where the cable sheaths are removed. After the sheath is cut, the low-capacity TG cable is slightly bent 2-3 times, from which the lead sheath breaks along the notch and is easily pulled off the cable. The sheath of a cable with a capacity of 300 pairs or more is removed using one or two longitudinal cuts.

After removing the lead sheath from the ends of the cable, the cores at the edge of the lead sheath are tied with calico tape or threads, which protects the insulation of the cable cores from damage on the edges of the sheath, after which the belt insulation is removed.

When cutting polyethylene casings, it is not allowed to tighten the casing. To remove it, it is enough to make one or two longitudinal incisions. Removing the polyethylene casing is much easier if it is preheated. Belt insulation, screen tapes and screen wire are kept by carefully twisting into rolls and tying them to the edge of the shell.

A coupling or parts thereof are pushed onto the prepared ends. Then the pairs of each layer are divided into two parts, smoothly bent and attached to the shell. In bundled cables, each bundle is bent and attached to the sheath.

Splicing cable cores

The cores are connected in pairs color to color, twisting into a twist or bundle into a bundle, the control pairs of each layer (bundle) are connected to the control pairs of another layer (bundle). Damaged pairs are connected last.

The connection of the cores starts from the bottom of the upper layer. After connecting the pairs of the lower bundle, the lower pairs of the next layer are spliced, etc. Then pairs of the central layer are spliced ​​and then the upper half in the order they follow from the center.

Splicing of a pair of cores with paper insulation is carried out as follows. Previously, paper or polyethylene sleeves are put on both cores. The cores are connected by twisting with the capture of two or three turns of paper insulation. Then, insulation is removed from each core and twisted together for a length of 12-15 mm, and at the beginning the twist is made weaker, and at the end it is denser. As soon as the strands are twisted to the desired length, the excess strands are bitten off and the twist is bent tightly to the strand. Paper sleeves are pushed into place of the twists, after which the pair is tied up on both sides with threads.

Further connection takes place in the same order, only it is necessary to place the twists and paper sleeves in a checkerboard pattern along the entire length of the coupling.

The cores of GTS cables with polyethylene insulation are spliced ​​in a similar way using polyethylene sleeves.

The cores of cables with polyethylene insulation can be twisted using the PSZH-4 device or connected with individual or multi-pair compressible connectors. With these methods, it is not necessary to remove the insulation from the connected cores.

After splicing of all cores insulated with paper (T cables), the splice is dried with hot air from a blowtorch or gas burner (using a metal casing). Plastic insulation should not be dried as it is neither heat resistant nor hygroscopic. Then the belt insulation is restored. The splice is wrapped with two or three layers of paper or calico tape (T cables) or plastic tape (TP cables). In addition, it is necessary to restore the electrical integrity of the screen. To do this, the splice is wrapped with the saved screen tapes, which are connected into a “lock”. The screen wire is connected by twisting at a length of 15-20 mm.

Installation of intercity symmetrical communication cables.

INSTALLATION OF THE CORE OF A SYMMETRIC CABLE

Before cutting the ends of the cable, the tightness and insulation resistance of the hose insulating covers of the spliced ​​cable sections are checked. Then an electrical check of the cable core is carried out; the ends of the spliced ​​cables are laid on the mounting goats, fixed and cut according to the specified dimensions. Near the edge of the jute (outer hose), the armor is cleaned to a shine and tinned for one third of the circumference by capturing both tapes. A copper wire bandage is applied to the tinned places, the ends of which are not cut off, since they are used for soldering the armor of spliced ​​cables, and in cables - without insulating covers and with a sheath (coupling). The bandage is soldered to the armor. According to the cut marks of the sheath, circular cuts are made and from them to the ends of the cable - two longitudinal cuts with a distance between them of 56 mm. The incised strip of the lead sheath is removed with pliers (Fig. 11.1), the sheath is moved apart and removed. The cutting of the cable ends before installation is shown in fig. 11.2. Prior to installation, the cylindrical sleeve is pushed onto one of the ends of the cable. Fours and pairs are divided into layers. The splicing of the veins begins with the central layer. Splicing technology and splice isolation are shown in fig. 11.3. In multi-quad cables, the twist points of adjacent quads are shifted relative to each other so that they are distributed evenly along the entire length of the splice. The soldering of the strands is carried out in a glass tin-lead solder of the POS type.

After drying over the flame of a blowtorch (especially cables with paper core insulation), the splice is wrapped with two layers of cable paper, between which a passport is placed on the mounted sleeve (Fig. 11.4).

Rice. 11.1. Lead Sheath Removal

Rice. 11.2. Cutting the ends of the cable before mounting the coupling:

1 jute; 2 wire bandage; 3 armor; 4 shell; 5 - thread bandage; 6 core; 7 - about water for soldering armor and shell; 8 - bandage soldering

Rice. 11.3. Splicing of intercity cable cores

The splicing of the cores of the GTS cables is carried out either by twisting or by compressible type connectors. Hot soldering of cores is usually used. On fig. Figure 11.5 shows stranded splicing. There are many varieties of compressible type connectors, but the multi-pair connector is most commonly used. Figure 11.6 shows a 20-core cable connector. The contact of spliced ​​cores is ensured by compressing the connectors using press technology. In this case, the insulation of the cores is cut through at the tips of the contacts and there is a reliable electrical connection all lived at the same time. The advantage of such connectors is good and stable contact resistance and reliable isolation lived. Multi-pair connectors are especially effective when installing large communication cables (over 500X2).

Rice. 11.4. Splice before soldering the lead sleeve

Rice. 11.5. Splicing of GTS cable cores

Rice. 11.6. Ten-pair connector for GTS cables

Features of the installation of cables with aluminum conductors consist in welding the ends of twisted conductors on the flame of a blowtorch or gas burner using a special flux, for example flux F-54A with operating temperature melting point 200°C. The connection of aluminum conductors with copper conductors is carried out using a copper-aluminum insert, which is a piece of aluminum wire coated at one end with a layer of copper

INSTALLATION OF COAXIAL CABLES

Features of the installation of coaxial cables are reduced to methods of splicing coaxial pairs, which, unlike symmetrical ones, require special care during laying out and installation, which excludes metal filings from entering the splice, the formation of dents, pinches and other deformations that lead to a violation of electrical characteristics.

Splicing of pairs is carried out directly, i.e., the first with the first, the second with the second, etc. For ease of installation, symmetrical quadruples and pairs are bent to the side, and spacer disks are installed between the coaxial pairs.

The cutting of coaxial pairs is carried out according to the template (Fig. 11.7). Three or four polyethylene washers are removed from each pair using a heated special fork. Instead, heat-resistant fluoroplastic washers are installed, which protect the coaxial pairs from deformation during subsequent mounting processes (soldering, crimping).

Rice. 11.7. Installation of coaxial pair type 2.6/9.5: o) splicing of the inner conductor; b) splicing of the outer conductor; screen restoration; c) splice

Splicing of the inner conductor is carried out using a copper sleeve with a slot, and the outer conductor and the screen using copper and steel split couplings, the necks of which are crimped with rings. The splice is isolated with a polyethylene sleeve. Then symmetrical fours are spliced. After the repair of symmetrical quadruples, the splice is wrapped with three or four layers of cable paper or glass tape, between which a passport is placed. The sealing of the lead sleeve, the installation and pouring of the cast-iron sleeve are carried out in the same way as on symmetrical cables.

For the installation of small-sized coaxial pairs of type 1.2 / 4.6, special tools and parts are used, mainly similar to those used on pairs of type 2.6 / 9.5. A feature of the installation of pairs of type 1.2 / 4.6 is that after cutting the coaxial pairs, a brass support sleeve (Fig. 11.8) is pushed onto each of them, fastening the ends of the screen tapes and creating support for copper and steel backup couplings during their crimping in the process of splicing the outer conductor and screen tapes

Rice. 11.8. Cutting a small-sized coaxial cable type 1.2 / 4.6 (one coaxial and one symmetrical pair is shown): / sheath; 2 isolation of a coaxial pair; 3 screen; 4 support sleeve; 5 outer conductor; 6 polyethylene insulation; 7 inner conductor; S symmetrical pair

In addition, to create a support under the outer conductors at the places of their cutting, plastic tubes are pushed onto the inner conductors until they stop against the pinch of the balloon insulation.

Installation of coaxial pairs of a combined cable is carried out with tools and parts used for KMB-4 and MKTSB-4 cables. For the convenience of cutting and splicing coaxial pairs 2.6 / 9.5, a spacer cone with a through longitudinal hole is used, through which a layer of small-sized coaxial pairs is passed. After cutting pairs 2.6/9.5 and removing the spacer cone, pairs 1.2/4.6 and single cores are removed from the inner layer in the intervals between pairs 2.6/9.5 and temporarily go around. First, pairs 2.6 / 9.5 are spliced, then pairs 1.2 / 4.6, and lastly symmetrical elements. For installation, a lead coupling with cutting cones is used.

SOLDERING THE LEAD CLUTCH AND BACKING THE PIT

The lead sleeve is pushed onto the splice and, with the help of a wooden hammer, its edges are formed in the form of cones that fit snugly against the cable sheath. When using a split sleeve, the edges of the longitudinal seam are located one above the other, while the lead overlap is made from top to bottom so that the solder does not get inside the sleeve. Solder type POS is used for soldering the coupling.

Solders are marked depending on the percentage of tin in them, for example, POS-30 (30% tin), POS-40 (40%), etc. In addition, the grade of solder indicates the content of antimony in it, for example, POSSU-40- 0.5 (i.e. antimony 0.5%). On fig. 11.9 shows a state diagram of a tin-lead alloy depending on the ratio of components and temperature. At a content of less than 16% tin, the POS is coarse-grained, and the soldering turns out to be fragile. The most durable and fine-grained lead soldering is obtained at 2931% tin (POS-30). (When soldering the conductive elements of the cable, solder grades POS-40 and POS-61 are used.)

When soldering lead sleeves, the temperature of the solder should be close to the melting point of lead while achieving the best molecular adhesion. But since in this case POS-30 is very liquid (see Fig. 11.9), it is necessary to tin the surfaces to be soldered at a temperature of about 250260 ° C, and then, gradually lowering the temperature, give the soldering the necessary shape. This is achieved relatively easily, since the interval of the plastic state of POS-30 is 73°C (256183°C).

The coupling is sealed as follows: the places to be soldered are heated with the flame of a blowtorch (gas burner) and wiped with stearin; a solder bar is heated above the soldering point (at the same time the soldering point is heated) until softened, applying it to the future seam. After sealing, the tightness of the seams is checked by pumping the coupling with air (through a valve soldered into it) and covering the seam with soapy foam. After checking, the valve is removed and the hole is sealed.

% tin O

% lead 100

Rice. 11.9. State diagram of tin-lead alloys

Rice. 11.10. Resoldering of armor and cable sheath

On cables without insulating covers, the ends of the copper wires from the bandages on the armor are twisted together and soldered to the sleeve (Fig. 11.10). When mounting couplings with insulating covers in order to monitor their condition during operation, soldering of the armor with the coupling is not performed: the end of the lead conductor is soldered to the coupling, the insulating cover is restored, on top of which the conductors from the bandages are laid and soldered together.

Rice. 11.11. Cast iron clutch

The cast-iron sleeve (Fig. 11.11) is designed to protect the lead sleeve from mechanical damage, as well as from soil corrosion. Before installing the coupling, a resin tape is wound on the cable so that it lies tightly in the necks of the cast-iron coupling. Then the coupling is poured heated to 130-140 ° C and cooled to the required temperature (depending on the type of cable and allowable temperature its heating) with bituminous mass through the hatch in the upper half of the coupling. Then the hatch is closed, and all bolts, nuts and places where the cable exits the coupling are filled with the same mass.

Before backfilling the pit, the location of the measuring post is fixed, which is usually installed against the middle of the cable sleeve No. 1 at a distance of 10 cm from the axis of the route towards the field.

In places where a measuring column cannot be installed (for example, on city streets, etc.), before backfilling the pit, it is necessary to fix the location of the couplings in the pit with drawing distances to permanent landmarks on the sketch drawing. Then the pit is filled up to about half the depth, a measuring column is installed and the previously excavated soil is laid in the pit.

INSTALLATION OF CABLES IN ALUMINUM SHEATH

Compared to cables in sheaths made of other materials, and especially of lead, cables in an aluminum sheath have a number of significant advantages: shielding properties are improved, mechanical strength is increased, weight is reduced, cost is reduced, etc. The disadvantages of aluminum sheaths include their low corrosion resistance and complexity of installation.

Splicing of aluminum shells can be carried out by the following main methods: hot soldering, gluing and crimping.

When hot soldering a layer of zinc-tin solder (CTS) is applied to the aluminum shell at the points of articulation with the lead sleeve, and a layer of tin-lead solder (POS) is applied on top of it. This process is called tinning. The lead sleeve is then soldered to the tinned sheath using PIC in the usual manner.

The combination of different metals (aluminum, lead, tin, zinc, etc.) with this method of installation often leads to corrosion, destruction of the soldering and depressurization of the couplings, which complicates the maintenance of the cable under excessive pressure. Given these shortcomings, the hot soldering method has received limited application.

Feature of the adhesive method consists in the fact that the cutting cones of the lead coupling are connected to the aluminum shell with glue by manual crimping (Fig. 11.12). Then, after mounting the core, the lead cylinder of the coupling is soldered to the lead cones in the usual way (Fig. 11.13).

Rice. 11.12. Manual crimping for adhesive method

Rice. 11.13. Cable installation in aluminum sheath adhesive method:

1 cable sheath; 2 glue line; 3 lead cone; 4 place of soldering; 5 soldering of the shell with the clutch; 6 lead cylinder; 7 splice core

By crimping method(Fig. 11.14) splicing of the ends of the aluminum tube-coupling with the aluminum sheath of the cable is carried out by pressing. Before pressing, the ends of the shell are expanded with a special device to approximately the diameter of an aluminum tube-coupling. To protect the cable core from deformation during the pressing process and to create the necessary support, steel support sleeves are inserted under the expanded part of the sheath. The contact surfaces of the shell and tube are carefully cleaned.

Crimping is carried out using a manual hydraulic press and special punch and matrix, providing a mechanically strong, tight connection.

Rice. 11.14. Installation of a cable in an aluminum sheath by pressing:

1 hose; 2 shell; 3 place of pressing; 4 support sleeve; 5aluminum tube; 6 splice core

INSTALLATION OF STEEL SHEATH CABLES

For installation, a conventional lead sleeve is used, the soldering of which is carried out after preliminary tinning of the steel shell with a special paste of the brand PMKN-40.

The installation technology is as follows: after removing the hose along the top of the corrugation, make a circular incision of the shell with a file, carefully clean it with a brush, wipe it with a rag soaked in gasoline, dry it, protect the end of the hose with two or three layers of glass tape; a layer of paste 0.5 - 1 mm thick is applied to the cleaned surface of the shell, heated evenly with a blowtorch until the paste ignites and changes its color to brown, carefully remove slag from the surface and the tinning process. The installation of the cable core and the soldering of the lead sleeve are carried out in the usual way.

Restoration of INSULATION COVERS

To protect the bare aluminum or steel shell and the mounted coupling from corrosion, regardless of the method of shell splicing, the insulating cover is restored. Recovery is carried out in a hot or cold way, as well as with the help of heat-shrinkable tubes. hot way provides for the application of several layers of a moisture-repellent sticky polyisobutylene compound (LPK) to the bare sheath, alternating with a winding of polyethylene tapes splice, parts of a plastic sleeve welded to the cable sheath are approaching.

The cold method differs from the hot one in that after applying to the splice of the CPC, instead of a plastic sleeve, several layers of heated bitumen-rubber mastic (MBR) are applied to it, alternating with winding with plastic tapes and protected by a layer of glass tape. Methods for splicing plastic hose covers with plastic sleeves or heat shrink tubing are described in the following paragraph.

INSTALLATION OF CABLES IN PLASTIC SHELL

Polyethylene shells are restored:

welding parts of a polyethylene sleeve with a cable sheath by wrapping the welding site with several layers of polyethylene tape and fiberglass; through which, with an open flame of a blowtorch (burner), the surfaces to be welded are heated to a viscous state, forming a monolithic joint;

pressing the splice of the cable core with the capture of the sheath heated to a viscous state with low molecular weight polyethylene (Fig. 11.15);

welding of parts of a polyethylene sleeve with a shell using an electric spiral placed between the surfaces to be welded (electric heating method);

multilayer winding of the splice of the core with the capture of the shell, with lubrication with a polyisobutylene compound, i.e., in a cold way.

At present, the most progressive and technologically advanced way of restoring the insulating covers of cables with metal sheaths and splicing cables in plastic sheaths is the use of heat-shrinkable tubes made of thermoplastic materials (polyethylene, polypropylene) and subjected to radiation vulcanization (irradiation with γ- and β-rays). If a tube made of such a material is heated and stretched, and then cooled in the expanded state, then the shape given to the part will turn out to be “frozen”.

Rice. 11.15. Pressing the splice with molten polyethylene:

1 manual press; 2 molten polyethylene; 3 mold; 4 joint; 5 cable

Rice. 11.16. Heat-shrinkable tube: a) in the initial position; b) after heating; 1 cable; 2 tube

If such a tube is pushed onto the cable splice and heated to a temperature higher than that at which the expansion (blowing) was performed, the tube shrinks, taking its original state, and tightly compresses the splice (Fig. 11.16).

To increase the tightness and strength of the joint, an adhesive layer is applied to the inner surface of the tube, which softens during heating, filling the gaps between the tube and the cable. The tube is delivered to the consumer in an expanded state with "elastic shape memory", the radial shrinkage is at least 50% of the inflated state.

For splicing cables with dissimilar sheaths metal with plastic. For this purpose, metal-plastic tubes (TMP) are used, consisting of steel tubes, on the outer surface of which a layer of polyethylene is applied by hot spraying (Fig. 11.17).

During installation, the metal sheath of the cable is soldered with a steel tube using a lead cone, and the polyethylene sheath is welded to the polyethylene layer of the TMP tube using a polyethylene sleeve.

Rice. 11.17. metal-plastic tube:

1 - a layer of polyethylene; 2 - steel tube; 3- epoxy compound; 4 place of soldering; 5 - lead cone

FEATURES OF INSTALLATION OF OPTICAL CABLES

The installation of optical cables is the most critical operation that determines the quality and range of communication over optical cable lines. The connection of fibers and the installation of cables is carried out both in the production process and during the construction and operation of cable lines.

Installation of OK is divided into permanent (stationary) and temporary (detachable). Permanent installation is carried out on fixed cable lines laid for a long time, and temporary installation on mobile lines, where it is necessary to repeatedly connect and disconnect the construction lengths of cables.

An optical fiber connector, as a rule, is a fitting designed to align and fix the fibers being connected, as well as to mechanically protect the splice. The main requirements for the connector are simplicity of design, low transient losses, resistance to external mechanical and climatic influences, and reliability. In addition to detachable connectors, requirements are imposed on the stability of parameters during multiple docking.

Rice. 11.18. Displacement of spliced ​​fibers: a) radial displacement; b) angular; c) axial

The main task of joining single optical fibers is to ensure their strict coaxiality, the identity of the geometry of the ends, the perpendicularity of the surfaces of the latter to the optical axes of the fibers, and a high degree of smoothness of the ends. An important requirement is also high stability of the state of the optical contact and low losses introduced by the splice. On fig. 7.81 shows the main possible displacement defects of optical fibers (radial, angular and axial displacement). The most stringent requirements are imposed by radial b and angular 0 displacement. The presence of a gap s between the ends of the fibers has less effect on the amount of losses.

CONNECTION OF OPTICAL FIBER

The most common ways of connecting optical fibers (OF) are:

Application of connecting tubes;

Detachable connectors;

Mechanical joints;

electric welding and the use of metal tips.

Recently, for the fixed installation of optical cables, the electric arc welding method has firmly established itself, and for detachable installation of multiple use, detachable connectors.

Consider some typical ways of connecting optical fibers.

Application of connecting pipesone of the most common ways to permanently connect fibers. It consists in the use of precision bushings or tubes, which, being made exactly to the outer diameter of the optical fiber, give it the required position and fix it. Tubes are mostly glass. The tapered ends of the tubes facilitate the insertion of the optical fiber. The design of one of these connections is shown in Fig. 11.19. The connector consists of a hollow glass sleeve / with a hole for pouring the immersion liquid 2, which also serves to match the refractive indices of the fibers being joined 3 and 4. The splice introduces an attenuation of about 0.30.4 dB.

plug connectorreusable, designed to connect optical fibers, is shown in fig. 11.20. Pre-prepared ends of optical fibers are inserted into the socket and the pin part of the connector. When performing the splicing operation, the ends of the optical fibers are closely connected to each other. Outside there is a sealed housing of the plug.

The most characteristic designmechanical jointshown in fig. 11.21. Connected fibers in splice 1, 2 inserted into a plastic sleeve 3 and the free space is filled with immersion liquid 4. providing a bonding and immersion effect (reduction of reflection losses from the ends). Outside, the splice is hermetically sealed and mechanically protected by coupling halves 5, 6.

Electric welding It is produced using an electric arc or a laser by heating the ends of the spliced ​​optical fibers. The splicing process of OM consists of the following operations (Fig. 11.22, a):

Adjustment of the alignment of the location of the ends of the OF, placed at a distance of several millimeters from each other;

Preliminary melting of the ends of the OF with an electric arc;

Tight pressing to each other of the ends of the OF, which are in a continuous arc discharge;

Final splicing step

Rice. 11.20. Mounting with connecting pipes:

1 glass tube; 2 immersion liquid 3 and 4 connectable fibers

Rice. 11.21. Detachable connection: a) socket; B) pin

1 fiber; 2 fiber coating; 3 - connector housing

Rice. 11.22. Mechanical splice: 1 and 2 fibers; 3 - plastic tube; 4, 5 - coupling halves

Rice. 11.23. Electric arc welding of fibers: a) splicing process; b) welding device;

1, 2, 3, 4 splicing stages; 5 and 6 fibers; 7 instrument; 8 microscope

The welding device is an easily portable device (Fig. 11.23, b) With overall dimensions 20X30X15 cm. Outside there is a microscope for adjustment and visual observation of the welding process.

This method of fiber welding makes it possible to obtain a joint with losses of the order of 0.10.3 dB and a breaking strength of at least 70% of the whole fiber. It is easily implemented in field conditions, since it does not require pre-treatment of the end surfaces before splicing.

At the end of each optical fiber is mountedmetal on tip (Fig. 11.24, a).

Rice. 11.24. Splicing with metal tips.: a) tip; b) fiber connection;

1 tip; 2 hole for pouring epoxy resin; 3 fiberglass; 4 capillary; 5 sleeve; 6 washers

To do this, from the end of the OF at a distance of 44 mm is removed protective covering. Then put on the tip 1 so that the glass fiber 3 protrudes from it by about 1520 mm. A capillary is put on the protruding end of the OF 4 (glass tube with a hole) 10 mm long. The capillary is inserted into the tip so that the end of the capillary protrudes 12 mm. A layer of epoxy resin is applied to the glass fiber and capillary 2. Epoxy resin is also poured into the holes of the tip. Then the end face of the OF is polished on a glass plate using abrasive powder and polished on a polishing wheel.

The connection of optical fibers is made using a sleeve 5 and split washers 6 (Fig. 11.24, b). The bushing and washers have threads, with the help of which the spliced ​​optical fibers are tightly joined.

INSTALLATION METHODS FOR OPTICAL CABLES

When installing an optical cable OK as a whole, it is necessary to ensure high moisture resistance of the splice, reliable mechanical characteristics for rupture and crushing and the suitability of the splice for a long stay in the ground.

Currently, various methods of mounting OK have been developed. Let's consider the most characteristic of them.

Frame assembly.For the installation of an optical cable, a metal frame is used with a number of longitudinal rods equal to the number of spliced ​​fibers (Fig. 7. 87, a). Optical fibers are spliced ​​in one of the above ways. Splices of fibers are placed on ebonite plates and fastened so that the splice does not experience a longitudinal effect on the gap (Fig. 11.25.6). Several layers of polyethylene tape are applied over the frame, and then a heat-shrinkable sleeve with an adhesive layer is put on (Fig. 11.25, c). The advantage of the coupling is the tight compression of the splice cones.

Installation of flat optical cables.The installation of cables made in the form of multi-fiber flat tapes with a common plastic coating is carried out as follows. The fibers at the end of the tape are exposed to a distance of 1 cm, and the tape is placed in a matrix, as shown in Fig. 11.26, a. The ends of the fibers are laid on a section having precision grooves, and a plastic material is poured into the matrix. Fibers embedded in plastic are kept in the matrix until it solidifies and then torn by bending and stretching them. The hardened plastic fixes the fibers at the end of the tape. The ends of the two tapes are laid in a template (Fig. 11.26, b), and in the gap between the ends to fasten the tapes to each other, they are filled with an epoxy compoundwith the correspondingrefractive index. The mold is detachable and is made ofbrass. According to the test results, the losses in such connectors are no more than 0.2 dB.

Rice. 11.25. Frame mounting: a) frame for six splices; b) fastening spliced ​​fibers; c) cable box;

1 frame; 2 fiber; 3 splices; 4 protective shell

Rice. 11.26. Installation of flat cables installation process; b") coupling;

1 precision grooves; 2- template; 3 - tape with fibers; 4 splice

Application of a curly connector.

A connector designed for multi-fiber cables and does not require grinding, polishing and gluing the fibers is shown in fig. 11.27.

Rice. 11.27. Curly connector: 1 fiber; 2 elastic plastic; 3 frame

Each fiberglass 1 securely held in the space formed by three cylindrical surfaces 2, made of flexible plastic. These surfaces create a centrally directed pressure on the fiber like a three-jaw drill chuck that holds the drill bit. After the two halves of the connector are installed, they are fastened together and each fiber is in its proper position between the three cylindrical surfaces. The frame is outside 3. Losses in the connector do not exceed 0.3 dB, transient losses exceed 70 dB. Outside, the splice is insulated with a heat-shrinkable sleeve with preliminary wrapping with plastic tapes.

Safety precautions when performing installation work

Installation work.Adhesive work is allowed for persons not younger than 18 years of age. Particular attention should be paid to meeting the requirements for safe handling with blowtorches and gas burners. The mass for pouring cast-iron couplings should be heated on braziers without open fire, while using a bucket with a spout and a lid. The temperature of the mass must be controlled by a thermometer.

Adhesives must be stored in a sealed container: do not allow the adhesive to come into contact with the skin or inhalation.

The work manager gives the order to start work only after a personal check of the absence of voltage on the cable. When cutting the cable, the hacksaw must be grounded to a metal pin driven into the ground to a depth of 0.5 m.

On cable lines that have proximity to an electrified AC railway, it is necessary: ​​a) to perform work only according to a previously issued order, which indicates the main safety measures; b) check the availability and serviceability of protective equipment, devices and tools; c) carry out the work of teams oh consisting of at least two people, one of whom is appointed responsible for the implementation of safety regulations; d) carry out all construction and repair work with the use of gloves, galoshes, rugs and tools with insulating handles; e) control the absence of voltage on the cores and sheaths of the cable using a voltage indicator with a neon lamp or a voltmeter.

SPHERING OF CABLE CONDUCTORS AND RESTORATION OF THEIR INSULATION

11.43. Copper cores of cables of local communication networks must be spliced ​​in one of the following ways:

· manual twisting with isolation of each vein by an individual sleeve or a pair of veins by a common sleeve;

mechanical connection using:

Group 10-pair compressible connectors SMZH-10;

25-pair modular connectors M S 2 series 4000 D ;

Single-core connectors type UY 2 "Scotchlok".

It is allowed to use individual and group connectors of other types, as well as devices for mechanized twisting of cores that have a certificate of conformity from the Ministry of Communications of Russia.

11.44. For manual twisting of cores, paper sleeves are used on T-type cables, polyethylene sleeves are used on TP-type cables. The dimensions of the sleeves are given in table. 11.3.

Table 11.3

Dimensions (mm) of insulating sleeves used for insulating cores of urban telephone cables

11.45. The process of splicing cores by manual twisting is shown in fig. 11.10.

Rice. 11.10. The process of splicing cores by hand twisting:

a) with isolation by individual sleeves; b) with insulation by a common sleeve

Sleeves are put on the conductors before splicing. In the process of splicing, the cores of the same name are crossed and twisted two turns together with the insulation. Starting from the place of twisting the cores in insulation at a distance of 30 - 40 mm, the insulation from the cores is removed with side cutters. The bare sections of the cores are folded together, squeezed with the fingers of one hand and twisted with 8-10 circular movements of the other hand over a length of 15-25 mm, depending on the diameter of the cable cores. The excess ends of the veins are cut off. The length of the cut twist should not be less than the size indicated in Table. 11.4.

Table 11.4

The dependence of the length of the twist on the diameter of the cable cores

In the place where the twist is cut, the ends of the cores must be tightly pressed against each other. The twist is bent away from the sleeve or vice versa, at the discretion of the jointer who assembles the coupling. The second core of the pair is spliced ​​in the same way.

11.46. When splicing cores and during the operation of cables, it is necessary to exclude breakdown, i.e. "scattering" of connected pairs and fours.

To do this, each pair or quadruple must be fastened with a dressing of threads (severe or nylon) or group rings made of the same material as the sleeves. The location of the twists in the sleeves, the installation locations of the group rings are shown in fig. 11.11. In the case of using a common sleeve, group rings or knitting with threads are not required.

Rice. 11.11. Methods for isolating twists of cores:

a) individual sleeves; b) common paired sleeves; c) common quadruple sleeves with mechanized twisting

When terminal devices are connected in parallel ( junction boxes, boxes and cable boxes) cores of three cables are connected together. The cores are spliced ​​by hand twisting, which is insulated with an individual sleeve.

11.47. Before splicing each next pair or group of cores, the splicer must determine their location on the splice. The strands closest to the edge of the sheath must be at least 40 mm apart from it. The twists of the cores of individual pairs (fours) or a group of such twists are evenly distributed along the entire length of the splice, displacing each subsequent group by half of the sleeve of the previous group. It is allowed to place the twists of the cores in a checkerboard pattern (Fig. 11.12).

Rice. 11.12. Placement of strands of cores along the length of the coupling:

a) with an offset of half the length of the sleeve; b) checkerboard

11.48. When splicing two cables with current-carrying conductors of different diameters, the strands of the conductors must be soldered if the difference in diameters is equal to or exceeds 0.3 mm. The ratios of the diameters are given in table. 11.5.

Table 11.5

The ratio of the diameters of the copper cores of the spliced ​​cables, at which the twists are subject to soldering

11.49. The twists are soldered with POSSU-40 solder using a solution of rosin in alcohol as a flux (three parts by weight of rosin to seven parts of alcohol). Soldering of twists is carried out in a glass soldering iron, heated by the flame of a gas burner or a blowtorch. Before soldering, the ends of the twists are smeared over a length of 8–10 mm with a solution of rosin in alcohol using a soft brush. The ends of the twists are immersed in molten solder by 2 - 3 cm. The length of the soldered section of the twist should be 5 - 8 mm. Soldering is carried out in groups of 6 - 8 pairs as they are spliced.

11.50. The method of core splicing using multi-pair connectors, in which 10 or 25 pairs are spliced ​​at one time without preliminary removal of insulation and the use of insulating sleeves, provides high quality installation and increased labor productivity compared to manual stranding.

11.51. Connectors SMZH-10 of domestic production are used for splicing the strands of urban telephone cables with polyethylene and paper-insulated.

The SMZh-10 connector (Fig. 11.13) consists of two halves: the lower (2), which contains all the metal contact elements, and the upper (3), which has grooves and protrusions that serve to press the lower half of the spliced ​​cores into the slots of the contact elements (1 ) and their fixations.

Rice. 11.13. Connector CSF-10:

1 - spliced ​​cores, 2 - connector base, 3 - connector cover

11.52. There are two types of SMZh-10 connectors available:

for splicing conductors with a diameter of 0.32 and 0.4 mm with a slot width of 0.26 - 0.29 mm;

for splicing cores with a diameter of 0.5 and 0.7 mm with a slot width of 0.39 - 0.43 mm.

When splicing conductors of different diameters, for example, when installing station branching couplings, connectors are selected for a smaller diameter of conductors.

The color of the connector body determines its purpose. White connectors are designed for cores with a diameter of 0.32 and 0.4 mm; any other color (except black) - for cores with a diameter of 0.5 and 0.7 mm.

Connectors are supplied in plastic bags, 100 pieces each. The package contains the manufacturer's form with the technical data of the connectors and the acceptance certificate from the QCD.

11.53. Crimping of connectors and at the same time cutting off excess cores is carried out using manual press equipment PSMZH-200 (Fig. 11.14) in compliance with the following technological sequence.

The base of the connector is placed in the appropriate socket of the press. The spliced ​​ends of the cores are brought into the socket of the connector and installed above the slots of the contact plate. The cores are fixed on the pins of the separating comb, the ends of the cores are clamped in a spiral spring. Then the base of the connector is covered with a lid. The lid is pressed by the folding bar of the press equipment. By turning the handle of the press, the parts of the connector are compressed and securely fixed in this position. In this case, the contact plates come into contact with the conductors, squeeze them, cut through the insulation and penetrate into the body of the conductors. As a result, reliable electrical contact between the spliced ​​cores is ensured. The crimped connector is removed from the press, and the next connector is mounted in the same way.

Rice. 11.14. Manual press equipment PSSMZH-200:

1 - body, 2 - bracket, 3 - bar, 4 - divider, 5 - pusher, 6 - knife, 7 - handle, 8 - spring fixing the wires

Connectors SMZH-10 in splicing are combined into compact groups. The number of groups depends on the capacity of the cable and the dimensions of the coupling. Connectors in a group should be tightly stacked one on top of the other, connectors of different groups should not touch each other (Fig. 11.15).

Rice. 11.15. Placement of groups of connectors SMZh-10 in splice

11.54. In addition to multi-pair connectors SMZH-10, which have found widespread use in the installation of GTS cables, modules M S of the 4000D series and single-core connectors UY 2 "Scotchlock" are produced.

M S modules are designed for simultaneous connection of 25 pairs of cable cores with a cross section of 0.32 - 0.7 mm with plastic (polyethylene, polyvinyl chloride) and paper insulation without its removal. The design of these connectors provides for the possibility of cutting the ends of the connected conductors, making the necessary measurements and correct installation module into the connection heads. The covers and bases of all modular connectors are removable.

11.55. The module consists of three parts: base, body and cover (Fig. 11.16). Each element of the module has a cut corner for proper installation in the connection heads.

Rice. 11.16. Module design M S:

1 - base, 2 - body, 3 - cover, 4 - cut corner

The M S 4000-D module is designed for direct connections. Its body has knives for cutting the ends of the veins. The lid and top of the case are painted ivory, while the bottom of the case and base are gold.

Module M S 4008-D is designed for paralleling pairs during cable switching and repair. The lower part of the body (green) has no knives, while the upper part (ivory) has knives. The base of the module is painted in green color, and the lid is ivory.

11.56. The cores are connected in modules using a special device - a connecting head (Fig. 11.17, a), which is used as an auxiliary element for placing the module and making it easier to handle the cores during their connection. The crimping of the module during the connection process is carried out by a hydraulic installation (Fig. 11.17, b), consisting of a manual hydraulic pump, a hose and a crimping clamp. The pressing process is stopped at a pressure of 20 kN.

When installing cables, a mounting device is used to fasten the connected ends of the cable (Fig. 11.17, c), consisting of a mounting rod (pipe section) 76 cm long with two movable clamps with brackets and straps, a transverse clamp, a clamp for attaching connecting heads. On one base, one or two connecting heads can be installed, fastened with four screws (Fig. 11.17, d).

Rice. 11.17. Mounting devices:

a) connection head:

1 - crimp terminal, 2 - conductor guides, 3 - pair separator, 4 - spring, 5 - connector bar, 6 - base

b) hydraulic installation; c) mounting bar; d) connecting heads on the base

11.57. The procedure for attaching the mounting device to the ends of the spliced ​​cables, attaching a cross clamp, installing bases with connecting heads, splicing cores with different insulation, crimping modules, bundles of splices into bundles is described in detail in the "Instructions for the use of modular connectors of the 4000 series brand M S company 3M".

11.58. To ensure high quality splicing when installing low-capacity cables, it is recommended to use single-core connectors, for example, type UY 2 "Scotchlock" (Fig. 11.18). The UY 2 connector is designed to connect copper conductors with a diameter of 0.4 - 0.9 mm with paper and polyethylene insulation without their preliminary stripping, while the maximum diameter of the conductor in the insulation should not exceed 2.08 mm. The body of the connector is filled with a hydrophobic mass that prevents moisture from affecting the junction of the conductors.

Rice. 11.18. Connector UY 2:

1 - cover, 2 - contact element, 3 - housing

The connector allows you to connect conductors with different core diameters and types of insulation. They are recommended for installation of low capacity cables (up to 100 ´ 2) and for splicing spare cores in cables large capacity. Installation of cables using a single-core connector is carried out using press tongs (E-9 Y), biting and pressing the conductors.

11.59. The splicing of cable cores with polyethylene insulation is carried out in the following sequence: pairs (fours) are selected from the selected bundles of cables to be connected, matching each other in color, and twisted in three turns at a distance of 40 mm from the edge of the sheath. Then, the cores of the same name (A1 and A2) are selected from the twisted pairs (fours) and, having put them together, trim, bite with press tongs at a distance of 40 mm from the place of twisting (Fig. 11.19, a). Having turned the connector with its transparent side towards itself, the prepared wires are inserted into it until it stops into the rear wall of the connector housing. The connector is crimped on the cores by the front working part of the press tongs. Next, two second cores of the same name (B1 and B2) are selected from the spliced ​​pair (four) and, having put them together, they are cut at a distance of 45 mm from the place of twisting. The cores are inserted into the connector and crimped (Fig. 11.19, b). In a cable with a four-strand core, the third and fourth cores are similarly prepared, cutting them off, respectively, at a distance of 50 and 55 mm from the twist point.

Places of twists of subsequent pairs (fours) are placed every 30 mm over the entire remaining length of the working area (Fig. 11.19, c). The remaining pairs (fours) are mounted against the places of twisting pairs (fours) of the first row. Having mounted the first bundle of cores, connect its core in three places at regular intervals, mount the remaining bundles of cable cores.

Spliced ​​bundles are tied together with a keeper tape in three places at regular intervals. Groups of mounted connectors formed after linking are evenly distributed around the circumference of the splice in a fan, starting from the first, and laid so that the connectors lie in one layer, and the diameter of the splice is the same along its entire length.

Rice. 11.19. Splicing cores with single-core connectors

11.60. A feature of splicing cable cores with paper insulation is that each pair of cores is put on a group ring (if knitting is not used). Pairs of the same name are pulled inside the working area and bent at a right angle at a distance of 40 mm from one of the cuts of the shell. In this case, it is impossible to allow violations of the insulation of the cores at the bend, they should be bent smoothly, holding at the bend with the thumb and forefinger.

11.61. Depending on the diameter, type and capacity of the installed cable, it is possible to recommend the selection of polyethylene and lead sleeves in accordance with Table. 11.6.

Table 11.6

Selection of MPS and MSS couplings and dimensions of CCI and TG cable termination

11.37.1 KSPP type cables can be mounted in the following ways:

a) with the help of dead-end couplings of the MT type, filled with bituminous compound;

b) with the help of dead-end couplings of the MT type, filled with Vilad-31 sealant;

c) by the "cold" method with the restoration of the shell with tape materials;

d) by the "cold" method in MPP bushings with filling of the splice with gels or compounds selected by the network operation services.

11.37.2 A technological operation common to all "hot" methods is the splicing of copper conductors by twisting with soldering with POSSU-40-2 solder. Soldering is carried out in a glass soldering iron heated by a gas burner or a blowtorch.

11.37.3 When installing KSPP cables using "cold" methods, the cores are connected using single-pair connectors designed for splicing cores with a diameter of 0.9 and 1.2 mm.

11.37.4 Installation of KSPP and KSPPB cables using dead-end couplings with bitumen compound includes the following technological operations:

a) cutting the ends of the cable;

b) tinning of armored tapes;

c) the imposition of bandages on armored tapes;

d) restoration of the screen tape;

e) splicing (twisting) of cores;

f) wrapping the cable with adhesive PVC tape and installing a spacer insert;

g) installation of the coupling and filling it with a heated bituminous compound;

h) immersion of the splice into the sleeve.

11.37.5 Cutting the ends of the cable (Figure 11.46) is performed in the following technological sequence:

a) cut off extra lengths cable ends and rags soaked in gasoline, clean them from dust and dirt over a length of 400 to 500 mm;

Figure 11.46 - Cutting the ends of the KSPPB cable with a spiral overlay screen

b) at a distance of 120 mm from the end of the cable, a circular incision is made on the polyethylene sheath and from it - longitudinal to the end of the cable, the incised sheath is unfolded and cut off along the circular incision; similarly remove the sheath from the other end of the cable;

c) PVC tape wound on an aluminum screen is unwound on KSPP cables and cut off at the sheath cut;

d) on KSPPB cables, at a distance of 10 mm from the edge of the sheath, a circular notch is made on the armored tapes, they are unwound and broken off along the notch; after that, the area freed from the armored tapes is cleaned of bitumen and wiped with a rag soaked in gasoline; similarly remove the armored tapes from the other end of the cable;

e) unwind the PVC tape wound on the screen and cut it off at the edge of the armored tape;

f) unwind the screen tape of spiral overlay and twist it into a roll at the cut of the shell; a screen wire is wound over the roll;

g) at a distance of 70 mm from the end of the cable, make a circular incision of the belt insulation, lightly heat the belt insulation with a burner flame, cut it crosswise between the cores and break off along the circular notch;

h) at a distance of 40 mm from the end of the cable, circular cuts are made on the core insulation with a knife and removed.

11.37.6 The areas of armor left near the cut of the shell are wiped with a rag soaked in gasoline, cleaned with a steel brush and tinned with POSSU-40-2 solder using PBK-26M paste with a hammer soldering iron.

A bandage of three turns of pre-tinned copper wire with a diameter of 0.9 to 1.2 mm is applied to each tinned section of the armor. The length of the wire for the bandage must be at least 200 mm. The bandage is fixed on the armor with a twist.

Then the bandage is soldered to the tinned section of the shell with a hammer soldering iron.

11.37.7 The two cut ends of the cable are folded in parallel so that the rolls of screen tapes do not interfere with the snug fit of the cable ends. The wires of the bandages are connected by twisting with soldering.

11.37.8 Splicing of copper conductors is carried out by manual twisting (Figure 11.47). The length of the twist must be at least 15 mm. The twists are soldered with POSSU-40-2 solder.

Figure 11.47 - Twisting of cable cores KSPP (KSPPB)

11.37.9 Rolls of screen tapes are unwound, each tape is shortened to 70 mm, folded together and fastened with a roof seam. Then both ends of the cable are wrapped around the waist insulation (with one turn). Over the screen tapes, the screen wires are wound towards each other with three turns and connected They are wound on the twist of the wires of the bandages with the twist of the screen wires, shortened to a value of 15 to 20 mm and the total twist is bent down.

11.37.10 With a brush dipped in an alcohol solution of rosin, lubricate the twists of the cores, as well as the bandage and screen

Rovolol and with the help of a soldering iron solder the twists. After soldering, the twist of the screen and binding wires is bent to the screen tapes.

An abundant layer of KR-1 hot melt adhesive is applied to the twists of the cores. Hot melt glue is applied to the twist along its entire length and the insulation of the cores in a section 20 mm long, starting from the edge of the insulation. A piece of tube HERE 8/4 (without underlayer) 80 mm long is pushed onto the twist so that it covers the entire area with the applied hot melt adhesive and seated along its entire length. After shrinkage HERE, without waiting for it to cool completely, its free end is folded into a splice and secured with a transfer or PVC adhesive tape.

11.37.11 At a distance of 100 mm from the cut of the sheath, at the ends of the cable, to ensure a gap between them, insert a spacer - a piece of sheath.

The coupling is applied to the twist of the cores and the level to which the cable will be immersed in it is determined so that the ends of the cores closed with tubes do not reach the bottom of the coupling by 10 to 15 mm (Figure 11.48)

Figure 11.48 - Fitting of the MT-36 coupling for splice

Both ends of the cable at this level are wrapped with five to eight turns of sticky PVC tape. The general view of the splice is shown in Figure 11.49.

Figure 11.49 - General view of the splice

11.37.12 The coupling is installed strictly vertically in a recess at the bottom of the pit. The heated bitumen compound from the kettle is poured into the coupling for 3/4 of its length. The thickness of the jet in this case should be from 2 to 3 mm. If the jet is thicker, the kettle with the compound is additionally heated, if it is thinner, they wait until it cools down to a temperature of 120°C. You can check if the compound is overheated by lowering a polyethylene sleeve or tape into it.

After pouring the coupling with the compound, a cable splice is introduced into it and immersed until the sheath begins to be wrapped with tapes (Figure 11.50)

The joint inserted into the coupling should not be moved.

Figure 11.50 - Installing the sleeve and immersing the splice into it

11.37.13 The cable stock is laid out at the bottom of the pit (Figure 11.4). Loose soil is poured into the gap between the cable and the bottom of the pit at the exit from the coupling and compacted. Then the pit is covered with excavated earth, without waiting for the vertically installed coupling to cool. Dead-end couplings filled with bituminous compound should only be installed in pits. In wells and near supports, bushings should be mounted.

11.37.14 The need for basic materials and fittings per one MT-36 dead-end coupling:

adhesive pvc tape. . . . . . . . . . . . . . . . 3 rolls;

gasoline B-70. . . . . . . . . . . . . . . . . . . 0.1 l;

bituminous compound. . . . . . . . . . . . . . . . 0.25 kg;

solder paste PBK-26M. . . . . . . . . . . . . 0.02 kg;

rag. . . . . . . . . . . . . . . . . .. . . . 0.1 kg;

solder POSSU-40-2. . . . . . . . . . . . . . . . 0.05 kg;

round copper wire with a diameter of 0.9-1.2 mm. . 0.2 m;

tube HERE 8/4, without sublayer. . . . . . . . . . . 0.4 m

glue-melt KR-1. . . . . . . . . . . . . . . . 0.05 kg.,

11.37.15 KSPP, KSPB and KSPZB cable splices mounted in MT-36 couplings can also be filled with Vilad-31 self-expanding polyurethane sealant. In this case, the installation of the joint is carried out as described above. Only the filling material changes. The advantage of the sealant is that the coupling can be used in any position after the sealant has cured. Therefore, it becomes possible to use dead-end couplings with MTO-type arms. MTO couplings increase the reliability of splices, since they allow inserting sheathed cables into the branch pipes of the arms and sealing the entries with TUT tubes, and connecting the armor outside the coupling, as shown in Figure 11.51. Installation of dead-end couplings with Vilad-31 sealant is allowed to be carried out at an air temperature of at least plus 5°C.

Installation is carried out in accordance with the provisions of the "Instructions for the installation of local communication cables with dead-end couplings with Vilad-31 sealant", St. Petersburg, LONIIS, 1995.

a) before sealing open areas of the armor "cold";
b) after sealing open areas of the armor "cold"
1 - outer coating of the KSPPB cable;
2 - open sections of armor with bandages;
3 - cable sheath;
4 - tubes HERE at sealed joints;
5 - sticky PVC tape; 6 - connection of screen tapes;
7 - strands of cores, soldered and insulated with tubes HERE;
8 - sealing open areas of the armor by
sequential imposition of layers of mastic MG 14-16,
adhesive PVC tape and moisture-curing bandage "Armoplast"

Figure 11.51 - Installation of the KSPPB cable in the 2MTO-36 coupling

11 37.16 When installing KSPP cables using tape materials for "cold" sealing, the cores are spliced ​​as in a bushing (Figure 11.52). At the same time, the twists are isolated with pieces of tubes HERE 4/2, seated on a layer of hot melt adhesive KR-1.

Then, each twist, closed with a tube HERE, with overlap and entry into the insulation on both sides of the HERE, is wrapped with a narrow Flat Tape VM. The width of the tape should be from 5 to 7 mm.

The splice of veins is pulled out and squeezed by hand. Over the splice, between the sheath cuts of the spliced ​​cables, the VM tape is wound. After winding two layers of VM tape, the screen wire is spliced ​​by twisting and soldering. The screen is restored by winding the splice with aluminum foil. A VM tape is wound over the restored screen to the level of the outer diameter of the cable.

Two layers of VM tape with 50% overlap are wound onto the cable sheath, stepping back 50 mm from its edge, through the splice onto the sheath of the second cable (by 50 mm). Two layers of 88T tape are wound onto the VM tape with 50% overlap. Two layers of "Armorcast" structural material are applied over the adhesive tapes.

With this method of installation, it is possible to splice the cores and screen wire using U1B or UDW2 pair connectors.

1 - cores are connected by twisting with soldering, insulation
restored with tubes HERE with KR-1;
2 - belt insulation restored with VM tape;
3 - layers of tape 88T;
4 - structural material "Armorcast"

Figure 11.52 - Installation of cables KSPP using materials for "cold" sealing company "ZM"

11.37.17 When installing KSPP cables with screens of longitudinal overlay, complete assembly kits of couplings are used, which include MPP couplings, as well as materials for splicing the cores, pouring the splice, restoring the screen and "cold" sealing of the coupling. For example, when

installation using a complete mounting kit of MPP 0.5-1x4 couplings, perform the following operations:

a) core splicing is carried out with U1B connectors. The splice length is the distance between the cutoffs of the shells, shown in Figure 11.53. The splice size is determined by the length of the screen rail included in the coupling kit;

b) the shield is repaired with two 4460-D shield connectors and an aluminum shield bus;

c) the internal volume of the coupling is filled with gel 8882 through one of the filling holes. After filling is completed, both holes are closed with stoppers;

d) the restoration of the sheath is carried out in a “cold” way, by applying belts made of 2900R mastic, fixed with windings of 88T adhesive vinyl tape, to the joints of the coupling parts and to the joints of the coupling with the cable.

At the choice of network operations services when compiling complete mounting kits may apply different kinds sealants. For example, compound 4407, "Vilad-13" and others.

The appearance and sections of the MPP 0.5-1x4 coupling at different stages of installation are shown in Figure 11.53.

11.37.18 PRPPM (PRVPM) cable splicing can be carried out in MT-16 dead-end couplings according to the technology given above in 11.37.4 - 11.37.12. Cutting and connecting the cores of single-pair cables with soldering are shown in Figure 11.54.

11.37.19 Splicing of PRPPM (PRPPM) cables with paired UDW2 connectors is allowed. The connectors have a black body, are made of UV-resistant material and can be used both in closures and outdoors, for example when hanging single-pair cables.

a) splicing of cores with U1B connectors, installation of shield connectors;
b) restoration of the screen, filling of the coupling, sealing of the coupling;
1 - KSPP cable; 2 - MPP-0.5 coupling; 3 - holes for filling the gel;
4 - shield connector 4460-D, installed on the shield and secured with one nut;
5 - connector U1 B;
6 - belt made of mastic 2900R, wrapped on top with tape 88T, on the cone of the coupling;
7 - the filling hole is closed with a polyethylene plug;
8 - a screen bus is installed on the screen connector stud, it is pressed from above with the second nut;
9 - screen bus; 10 splice;
11 - a belt of mastic 2900R, wrapped on top with tape 88T, at the junction of the coupling parts;
12-gel 8882

Figure 11.53 - Mounting the bushing on the KSPP cables in a cold "method using the MPP 0.5-1x4 coupling kit

1 - soldered section of the twist; 2 - stranding