RU60778U1 - ELECTRIC COMMUNICATION CABLE (OPTIONS) - Google Patents

Abstract

An electric communication cable is proposed, including two conductive cores equipped with insulating sheaths and twisted into a pair, over which a shielding metal-polymer sheath with a screen wire located underneath is applied. The insulating shell of each core is made of a material containing polyethylene and polypropylene, taken in an amount of from 6% to 48% by weight of polyethylene. The shielding shell is made in the form of an adhesively interconnected outer layer of flame retardant polymer and an inner metal layer.

Description

The utility model relates to the cable industry and can be used in the construction of communication and signaling cables.

Known electric single-pair communication cable of the type KVSM, which includes two conductive conductors with a diameter of 0.4 mm, equipped with insulating sheaths of polyethylene with individual colors and twisted into a pair, on top of which an aluminolavan shield is applied with a metal layer inside with a screen wire under it. A moisture-proof polyvinylchloride shell is applied over the screen, which does not spread combustion (Journal of “Technologies and Communications”, 2004, Mytishchi, Moscow Region, Utility Equipment, pp. 97-99).

However, this cable cannot be used to transmit high-frequency digital signals, since the material of the insulating sheath of conductive wires is heterogeneous, has a roughness, which leads to a deterioration in the transfer function of the cable line.

The closest technical solution in relation to the claimed utility model is the electric communication cable disclosed in the utility model of the patent No. 51782, class H 01 B 11/00. This cable contains conductive conductors tinned copper or soft copper, single-wire or flexible multi-wire, equipped with insulating sheaths made of a material containing polyethylene and polypropylene, taken in an amount of 6% to 48% by weight of polyethylene, the wires are twisted into a pair over which a screen with tinned or soft copper, single-wire or multi-wire, linear or multi-curved, shielded copper wire laid under it, the cable contains a polymer material lagozaschitnuyu sheath flame retardant and between this shell and the screen is available airspace.

This well-known communication cable can be used to transmit high-frequency digital signals, due to the fact that the insulating shell of each core is made of a polymeric material containing polyethylene and polypropylene, taken in an amount of from 6% to 48% by weight of polyethylene.

However, this cable, if it is in the water for a long time, does not provide protection against diffusive seepage of water into the space under the screen of the pair. it

due to the fact that all polymeric materials allow diffusion seepage of water in the presence of it from the outside and the pressure difference between the outer and inner sides, which, as a rule, is implemented in the cable. The ingress of moisture under the screen of the pair leads to a deterioration in electrical parameters and, ultimately, to the termination of communication in general.

The technical problem of the proposed utility model is the creation of an electric communication cable having enhanced operational capabilities by preventing diffusion leakage of moisture into the cable while maintaining the required electrical parameters.

The technical problem is solved by the fact that the proposed electrical communication cable, including two conductive wires, tinned copper or soft copper, single-wire or flexible multi-wire, equipped with insulating sheaths made of a material containing polyethylene and polypropylene, taken in an amount of from 6% to 48% of masses of polyethylene twisted into a pair, on top of which a shielding metal-polymer sheath with a shield wire laid under it, copper, single-wire or multi-wire, linear or many multiple curved, the specified shielding shell is made in the form of adhesively bonded to each other over the entire contact surface of the outer flame-retardant layer of polymer and the inner metal layer.

The presence of an inner metal layer over the entire surface of the shielding prevents the diffusion of moisture into the cable, as a result of which the cable retains the required electrical parameters, for example, the electrical insulation resistance of the cable remains almost unchanged, regardless of the operating conditions of the cable.

It is advisable when laying the cable into the ground that a single-pair cable additionally contains a layer of water-blocking material superimposed on the said shielding sheath, armor made of metal wires and a moisture-proof hose.

To enable the cable to be suspended on poles and communication supports with gripping-type clamps, it is desirable that the cable additionally contains a protective sheath located on top of the said shielding sheath and a cable placed in it parallel to a pair of conductive conductors.

The technical problem is also solved by the fact that it is proposed an electric communication cable, comprising at least two electric single-pair cables made according to claim 1, placed in a protective sheath.

This design of the cable simplifies the technology of laying several identical single-pair cables that perform the same functions.

It is advisable to ensure compact design that in the proposed multi-pair cable, at least two of the aforementioned electrical single-pair cables are twisted together into a core placed in the said protective sheath made of a moisture-proof material that does not propagate combustion.

For laying the cable directly into the ground, it is desirable that the multi-pair cable additionally contains a layer of water-blocking material superimposed on the protective sheath, armor made of metal wires and a moisture-proof hose.

To suspend the cable on poles and communication supports with spiral clamps of a twisting type, it is advisable that the multi-pair cable additionally contains a cable and at least two of these single-pair electrical cables twisted around it into the core, while the core is placed in the said protective sheath.

It is advisable to suspend the cable on poles and communication supports with gripper-type clamps so that the multi-pair cable contains at least two of these electrical single-pair cables twisted into a core and additionally contains a cable placed in the said sheath parallel to the length of the core.

In the future, the proposed utility model is illustrated by specific examples of implementation and the accompanying drawings, in which:

figure 1 depicts a cross section of the proposed single-pair electric cable;

figure 2 depicts a cross section of a multi-pair electrical cable;

figure 3 depicts a cross section of an armored electric cable;

figure 4 depicts a cross-section of a single-pair cable or multi-pair cable with a cable integrated in the protective sheath;

5 depicts a cross section of a multi-pair electrical cable with a cable integrated in the core.

A single-pair cable 1 (Fig. 1) consists of two conductive cores 2, each of which is equipped with an insulating sheath 3 made of a material containing polyethylene and polypropylene, and the polypropylene content should be from 6% to 48% by weight of polyethylene. Insulated cores 2 are twisted together in a pair,

on top of which a shielding metal-polymer sheath 4 is applied with an under-screen wire 5 under it. Sheath 4 is made in the form of an adhesively interconnected outer non-propagating layer of polymer 6 and an inner metal layer 7, due to which moisture does not penetrate into the cable, which allows it to keep its required electrical parameters, for example, the electrical insulation resistance of the cable, remains virtually unchanged.

To expand operational and technological capabilities, conductive cores 2 and screen wire 5 can be made of the following materials.

When using connectors with knife connectors, the conductive conductors 2 and the shield wire 5 are made of soft copper single-wire.

When using connectors with soldering cores 2 and screen wire 5, they are made of tinned copper single-wire.

When installing the cable with screws under the plinth, the conductive conductors 2 and the shield wire 5 are multi-wire from soft copper wires.

When using the cable in a humid climate with possible corrosion of copper and when mounting it with screws for the plinth, the conductive conductors 2 and the shield wire 5 are multiwire from tinned copper wires.

The screen wire 5 can be made repeatedly curved, which simplifies the technology of applying a shielding metal-polymer sheath 4 by partially laying it between the turns of a pair of insulated conductive cores 2.

Figure 2 shows a multi-pair electrical cable 8, comprising at least two electric twisted together in the core of a single-pair cable 1, covered with a common protective sheath 9 made of plastic and not spreading combustion.

To ensure the possibility of laying directly into the ground, an armored cable 10 is made (Fig. 3), the core of which is a single-pair cable 1, over which a layer 11 of water-blocking material, armor made of round wires 12, applied in layers or in the form of a braid, a moisture-proof polyethylene hose 13 .

Also, the core of the armored cable 10 can be a multi-pair cable 8, over which a layer 11 of water-blocking material is applied, the armor of

round wires 12, applied in a twisted or braided manner and a moisture-proof plastic hose 13.

For the suspension on the supports of communication lines and fences, cables 14 with a built-in cable 15 (Fig. 4) or multi-pair cables 16 with a built-in cable 17 (Fig. 5) are manufactured.

Cable 14 includes a single-pair cable 1 or the core of a multi-pair cable 8 formed of twisted at least two single-pair cables 1, a cable 15 and an additional protective sheath 18. The cable 15 is placed in the sheath 18 parallel to the core or parallel to a pair of conductive cores. Cable 16 (figure 5) consists of a cable 17, with a polymer insulating layer 19 and twisted around it in the core of single-pair cables 1 and overlaid with a common protective sheath 20.

Cable manufacturing technology according to the claimed utility model includes the following operations.

Conducting cores 2 are made of copper wire "wire rod", usually with a diameter of 8 mm by drawing. Depending on the diameter of the finished conductive core, the following operations can be used: coarse and medium drawing or coarse, medium, fine drawing.

Conducting cores 2 can be tinned copper, un tinned copper, single-wire and multi-wire.

Single wire tinned wires are annealed to provide softness. Annealing is not required to obtain tinned veins. Tinning is done in a hot way, as a result of which the core becomes soft.

For stranded cores, the same technology is used to produce wire in the required amount, which is then twisted in the required combination on cigar, frame or lamp machines.

The insulating shell 3 on the conductive conductors 2 is applied by extrusion from a mixture of granules of technical polypropylene and polyethylene obtained before loading into the hopper of the extruder. Twisting of cores 2 with a polyolefin insulating sheath 3 in a pair is usually carried out on frame type machines.

Screen wire 5 in combination with a copper layer of a metal-polymer shell is made in the form of a soft copper wire, in combination with an aluminum layer - in the form of a tinned copper wire, can be laid in a straight and zigzag shape, previously curved (corrugated) on a special device. In some cases, the screen wire is made flexible multi-wire. Technology

the manufacture of screen wire is the same as the technology for the manufacture of a conductive core.

The shielding metal-polymer shell 4 is made as follows.

As a blank, a two-layer tape is taken, consisting of a metal layer coated with a thin polymer layer, homogeneous with the main polymer provided for the manufacture of the shell.

The tape is fed longitudinally into the coiling device with the metal inward and then into the head of the extrusion line, where the bulk of the molten polymer is superimposed on it under pressure on the passage.

Homogeneous polymers are welded together, but the adhesive forces that existed in the bilayer tape of the billet are preserved, which allows one to finally obtain a metal-polymer shell with a uniformly distributed metal layer on the inner surface of the shell, adhesively bonded to the polymer layer over the entire contact surface.

The plastic moisture-proof sheath 9 of multi-pair cables 8 can be made both from polyvinyl chloride plastic compound and from a halogen-free compound by extrusion or from any polymer that ensures no spread of combustion.

For armored cable 10, cable 1 or multi-pair cable 8 is taken, onto which a tape of water-blocking material 11 is applied by winding in a spiral on a winding machine. Also, a tape of water-blocking material can be passed under armor 12 for booking operations. The application of the armor 12 can be carried out in the form of a braid with galvanized steel wires or the like on a braid machine or in a braid on a reservation machine.

Moisture-proof hose 13 is applied, as a rule, from polyethylene on an extrusion line.

A cable 15 or 17 is usually bought ready made, twisted from metal wires, glass fibers or strong synthetic threads. The polymer insulation 19 of the cable 17 can be made of any polymer material by extrusion.

The protective shell 18 or 20 is preferably made of polyethylene by extrusion, however, other polymers can be used instead of polyethylene. In this case, for the cable 14, shown in figure 4, the sheath is superimposed on the core and the cable at the same time. In the core of the cable 16 shown in figure 5, the cable

laid in the core for twisting operations, and the cable enters longitudinally, and single-pair cables are twisted around it.

To confirm the technical result, samples of an electric cable I (patented) with a shielding sheath having an inner layer in the form of an aluminum-polyvinyl chloride tape and an outer layer of non-combustible polyvinyl chloride material and an electric cable II (known, type KVSMV) with a screen of aluminum-polyethylene terephthalate tape were made and polyvinyl chloride sheath, which were tested for moisture diffusion under an overpressure of 1 atm. through a moisture barrier over a length of 1 m for 30 days. At the same time, the insulation resistance measured over a cable length of 10 m was selected as a criterion for cable failure. The test results are shown in the table.

Cable name Electrical insulation resistance, megohms Sample No. 1 Sample No. 2 Sample No. 3 Before the test After test Before the test After test Before the test After test Cable I 7700 7300 6400 6800 5800 6100 Cable II 6300 0.67 8500 1,2 7200 0.9

As can be seen from the table, the insulation resistance of the samples of patented cable I practically did not change, and the samples of the known cable II show a decrease in electrical insulation resistance as a result of moisture diffusion through the moisture barrier

Claims (8)

1. An electric communication cable, including two conductive conductors, tinned copper or soft copper, single-wire or flexible multi-wire, equipped with insulating sheaths made of a material containing polyethylene and polypropylene, taken in an amount of 6 to 48% by weight of polyethylene, twisted into pairs , tinned copper wire or soft copper wire, single-wire or multi-wire, linear or repeatedly curved, characterized in that a screening metal is applied over the said screen wire The black shell, made in the form of adhesively bonded to each other over the entire contact surface of the outer flame-retardant layer of polymer and the inner metal layer. 2. The cable according to claim 1, characterized in that it further comprises a layer of water-blocking material superimposed on the metal-polymer shielding sheath, armor made of metal wires and a moisture-proof hose. 3. The cable according to claim 1, characterized in that it further comprises a protective sheath located on top of the shielding metal-polymer shell and a cable placed therein parallel to a pair of conductive wires. 4. An electric communication cable, comprising at least two electric single-pair cables made according to claim 1, in a protective sheath. 5. The cable according to claim 4, characterized in that at least two electric single-pair cables are twisted together in a core placed in said protective sheath made of a moisture-proof material that does not spread combustion. 6. The cable according to claim 5, characterized in that it further comprises a layer of water-blocking material superimposed on the protective sheath, armor made of metal wires and a moisture-proof hose. 7. The cable according to claim 4, characterized in that it further comprises a cable and at least two electric single-pair cables twisted around it into the core, the core being housed in a protective sheath. 8. The cable according to claim 4, characterized in that at least two electric single-pair cables are twisted into a core, and it further comprises a cable placed in a protective sheath parallel to the core.