RU192298U1 - Cable symmetric high-frequency flexible cold-resistant brands KSVPtp-HL, KSVPtpE-HL, KSVPtpT-HL, KSVPtpET-HL - Google Patents

Abstract

The utility model relates to electrical engineering, specifically to high-frequency cables for digital communication and control systems in the frequency range up to 1200 MHz according to IEC 61156-8 and for structured cable systems in accordance with ISO / IEC 11801-6, is designed to work in alternating temperature conditions with increased requirements for flexibility and cold resistance of the cable. EFFECT: increased reliability of cable operation in conditions of alternating temperature due to increased cable flexibility (small bending radius), small residual deformations of insulation and sheath, high stability in conditions of tight installation under alternating temperature conditions with possible periodic cooling to minus 70 ° С. The cable can be used for installation of an onboard cable network of aviation and rocket and space technology. The claimed utility model differs from the prototype in the new cable design: a thermoplastic elastomer (TPE) is used as the material of the outer sheath, which has high flexibility and high impact strength at low temperatures, and the insulation of the conductors is made of polyethylene. 4 s.p. f-ly, 2 ill.

Description

The utility model relates to electrical engineering, specifically to high-frequency cables for digital communication and control systems in the frequency range up to 1200 MHz according to IEC 61156-8 and for structured cable systems in accordance with ISO / IEC 11801-6 [1], is intended for work in alternating temperature conditions with increased requirements for flexibility and cold resistance of the cable (climatic modification UHL1, UHL2 in accordance with GOST 15150).

Such cables, as a rule, contain several cores insulated by a sheath consisting of one or several layers. The outermost layer is called the outer shell, and currently it is made of a polymeric material, preferably polyvinyl chloride (PVC) or polyethylene (PE).

State of the art

The main polymer materials for the production of cable products in the world today are polyolefins. At the same time, in the cable industry in Russia and the CIS countries, PVC plastic compounds remain the most common (more than 60% of the total volume of consumed polymers), followed by polyethylene compounds (only about 37%) [2].

The modern cable products market for high-frequency communications requires the use of new high-performance polymeric materials with a working temperature range from minus 70 to plus 130 ⁰ С. Polypropylene compounds based on propylene block copolymer with ethylene and thermoplastic elastomers are undoubtedly promising from this point of view.

High-frequency communication cables in their design are similar to telephone cables of the TPP brand and station brands TSV, containing two or more symmetrical pairs, the cores of which are polymer-insulated and twisted into a core, with or without a shield, and a sheath made of PVC compound manufactured in accordance with TU 16 .k71-005-87, however, these cables cannot be used to transmit high-frequency signals due to high dielectric losses, and their cold resistance is not high.

In the frequency range from 100 MHz and higher, twisted-pair cables for structured cable systems of stationary horizontal and vertical laying with the number of pairs from 2 to 25 and the outer diameter from 4.8 to 12 mm are most in demand. The main elements of such a cable are a multi-core core of insulated copper conductors, with or without a shield, enclosed in plastic, incl. polyethylene, protective shell.

The high-frequency cable OJSC “Electrocable Kolchuginsky Zavod” (patent RU27962 U1) for structured cable systems based on twisted pair with copper conductors with continuous polyethylene insulation in a PVC sheath, the so-called “horizontal cable” of NVP brand according to TU 16.K01, is known from the prior art -31-2002. The cable consists of copper insulated conductive wires that make up twisted pairs twisted into a core; The core insulation is made in the form of layers, while the outer and inner layers are made of continuous polyethylene, the middle layer is made of foamed polyethylene. The core is enclosed in a sheath made of PVC compound.

Also known is a symmetric high-frequency shielded cable according to the description of the patent for utility model RU40819 U1, IPC Н01В 11/00, H01B 11/02, containing a core formed by insulated polyethylene or porous polyethylene conductive conductors twisted together in a pair and a filler made of polymer filaments, at least some of which are placed between insulated cores and a screen, on top of which is a sheath of polyvinyl chloride plastic compound. The filler is made in the form of polypropylene film fibrillated non-twisted yarns, applied longitudinally, the other part is located between the insulated cores and the screen.

The disadvantages of cables according to patents RU27962, RU40819 include insufficient cable flexibility and insufficient resistance to temperature differences due to the use of PVC plastic sheath as the sheath material.

Known electrical communication cable according to the patent RU51782U1, IPC H01B 11/00, and a similar electrical cable according to the design according to patent RU60778U1) of the NTZ-Teploskat LLC. The cable includes two conductive cores equipped with insulating sheaths and twisted into a pair, over which a screen is applied and a moisture-proof sheath made of a polymer material that does not spread combustion. The insulation 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 problem that is solved in the known technical solution is the creation of a communication cable with structural elements homogeneous along the length of the cable, ensuring the stability of high-frequency parameters and the optimal transmission of high-frequency digital signals. It is noted that the use of only polypropylene or the addition of polypropylene in excess of 48% by weight of polyethylene is not permissible, as this worsens the cold resistance of the cable. The plastic moisture-proof sheath of single-pair and multi-pair cables according to the patents RU51782 or RU60778, as in the analogs given above, is made mainly of PVC, with the already noted drawbacks.

Known flexible cable with polyethylene insulation in a polyvinyl chloride sheath according to patent RU59317 U1, IPC H01B 9/00, 2006, manufacturer - "Electrocable" Kolchuginsky Zavod. The cable contains multi-wire conductors in its design. It is used for switching cable segments of a structured cable system for the transmission of signals in the frequency range of use up to 100 MHz at a voltage of up to 145 V AC with a frequency of 50 Hz or 200 V DC Development of a flexible cable with a thickness of polyethylene increased to 0.25 mm Insulation and twisting of insulated conductive wires in twisted pair allows the cable to be resistant to repeated bends, which makes it possible to expand the range of cable products for structured communication systems. An essential feature of the utility model is the presence of a multi-wire conductive core in its design. According to the applicant, this feature allows lay cables with a smaller bending radius than for single-wire horizontal cables, however, the characteristics of rigid polyvinyl chloride sheaths during cable operation are not taken into account. At the same time, the cable is functional in a limited temperature range from minus 20 ° С to plus 60 ° С and at low temperatures small bending radii are very unreliable.

Also known are shielded high-frequency cables KSVPPE-5e and KSVPP-5e with twisted pair in polyethylene insulation and in a sheath of light-stabilized polyethylene produced by NPO Farial LLC according to TU FKS-002-2016, which are not flexible enough to solve the task.

Common disadvantages of analogues: insulating and protective materials must satisfy a number of requirements for properties, which in some respects are contradictory. So, important mechanical properties of the cable sheath are high mechanical strength, low shrinkage, the material should be easily processed, and maintain elasticity over a wide temperature range. For insulation, good adhesion to metal, a minimum of roughness, a low value of dielectric loss, and also high resistance to cracking under the influence of environmental stress are required. Since before it was difficult or even impossible to simultaneously satisfy all these requirements, the materials of shells and insulation mastered by manufacturers were the result of a compromise: good properties in one respect were achieved due to worse properties in some other respect.

Known flexible cable according to patent RU69677 using thermoplastic elastomers. The cable contains twisted copper conductive conductors, each of which is coated with polymeric insulation from olefin thermoplastic elastomer, and an external polymer sheath made of polyvinyl chloride plastic compound of the O-50 VD grade.

Thermoplastic elastomers (TEC) used in this known technical solution are materials obtained by mixing olefin rubber with an olefin thermoplastic. Mixed olefin thermoplastics at elevated temperatures (more than 90 ° C) have unsatisfactory physical and mechanical properties and have low resistance to aggressive environments. In this regard, the scope of mixed olefin thermoplastics for cables is very limited.

The disadvantages of the analogue of RU 69677:

- operating temperature reduced to 90 ° C;

- reduced specific electrical insulation resistance of conductors;

- reduced resistance to bending the outer shell of PVC compound, especially in difficult temperature conditions;

- limited scope (mobile rail transport).

Among the well-known technical solutions closest to the claimed utility model for designation and to patent RU183147, IPC H01B design features is a high-frequency balanced cable on 11/02, published: 09/12/2018 (selected for the prototype). The cable provides the transmission of digital and analog signals at frequencies up to 100 MHz when exposed to ambient temperatures up to 100 ° C. The cable includes a core consisting of at least two pairs of twisted conductive conductors. The core insulation is made of a composition based on a block copolymer of propylene with ethylene, the core is placed in a winding of a polyethylene terephthalate film. The cable is enclosed in a sheath made of a polymer composition, for example, polyurethane. The technical result of the prototype is to increase the resistance of the cable to repeated bends.

The cable according to the technical solution of the prototype is not suitable for continuous operation at low temperatures.

It is known that a block copolymer of propylene with ethylene is less resistant to the effect of lower temperature than, for example, polyethylene or cross-linked polyethylene. Already at minus 50 it becomes brittle, and the use of such cold-resistant insulation in the construction of the cable under alternating reduces its reliability, especially if a batch temperature falls to minus 60-65 ^{° C,} as occurs for example in the vehicle and aviation cabling rocket and space technology. A cable sheath made of a polymer of the polyurethane type also has the same drawback, which leads to a decrease in the cable service life. An additional disadvantage is the high viscosity of the polyurethane at extrusion temperatures of 3-5 g / 10 min.

The protective measures taken for twisted pair cables are nullified if the conditions for their installation are violated. The bending radius of products using block copolymers of propylene with ethylene is strictly limited and usually should not be less than eight to ten diameters. Moreover, in an alternating temperature regime with the possibility of deep cooling (up to minus 70 ^о С), residual deformations, up to cracking, can appear in the shell. If this is not taken into account, then geometric changes occur inside the cable, sometimes irreparable, worsening its transposition and protection from sources of electromagnetic interference, for example, from neighboring twisted pairs or from third-party electrical equipment.

The design of the cable prototype does not provide operation in alternating temperature conditions, including deep cooling to minus 70 ° C, for example, in computer communications of aircraft or weapons and military equipment. The cable is produced in a straight line, so mounting bends, even in a static position, are inevitably in a state of mechanical stress. When operating in extreme conditions, the sheath is destroyed, the transposition of twisted pairs is violated, worsening the electrical characteristics of the cable.

When manually switching various cable segments of a structured cabling system in a limited space of mounting cabinets, the cable must be resistant to alternating temperature loads at small bending radii, which cannot be achieved using a sheath made of polyurethane or another polymer, for example, polyvinyl chloride plastic or polyethylene.

The objective of the proposed technical solution is to eliminate the noted drawbacks of cables of the same purpose and increase the reliability of the cable at lower temperatures relative to the analog. This implies the creation of a symmetric high-frequency flexible cold-resistant cable, reliable when operated in alternating temperature conditions, including deep cooling, for example, in computer communications of aircraft or military equipment.

The disadvantages of the prototype are eliminated by the fact that the insulation of the cores is made of polyethylene, in particular cross-linked polyethylene, and the shell is made of thermoplastic elastomer (TPE) having high flexibility and high impact strength at low temperatures.

Utility Model Essence

The problem is solved in the claimed formula of the utility model: in a cable containing at least two twisted pairs of metal conductors, with or without a shield, having plastic insulation and enclosed in a protective outer sheath, the twisted pair cores have insulation made of polyethylene, and as an external material shells used thermoplastic elastomer (TPE), which has high flexibility and high impact strength at low temperatures.

In addition, in a specific embodiment, the insulation of the twisted pair cores can be made of cross-linked polyethylene, for example, by gamma radiation.

In addition, as mentioned thermoplastic elastomer can be used styrene elastomer obtained by mixing polyolefins and block copolymers of styrene-ethylene-butylene-styrene (SEBS).

In addition, as mentioned thermoplastic elastomer can be used vulcanized elastomer obtained by dynamic vulcanization of a mixture of polyolefins and ethylene-propylene-diene rubber (EPDM).

In addition, a mixture of polyethylene and polypropylene in equal or predominantly polyethylene mass fractions can be used as the mentioned polyolefins, which provides the melt flow rate of the elastomer according to GOST 11645-73 in the range (5 - 7) g / 10 min at a temperature of 190 ° C.

Figure 1 shows a diagram of the design of the cable.

1 - copper core;

2 - insulation of LDPE / cross-linked polyethylene;

3 - screen (optional);

4 - TEC shell;

Figure 2 shows the temperature zone during the formation of the TEC shell.

5 - food zone;

6 - dosing zone;

7 - melting zone;

8 - extrusion zone;

9 - forming head.

The features of the claimed symmetric high-frequency cable, coinciding with the essential features of the cable according to patent RU183147 and allowing you to choose it for the prototype.

- cables have the same purpose;

- the presence of conductive conductors made of copper wire;

- the presence of a core consisting of two or more conductive cores;

- polymer insulation of current-carrying conductors;

- the presence of a flexible protective shell.

The claimed utility model differs from the prototype in a new cable design: instead of a polymeric composition such as polyurethane, a thermoplastic elastomer (TPE) is used as the material of the outer sheath, which has high flexibility and high impact strength at low temperatures, and the insulation of the conductors instead of the block copolymer of propylene with ethylene is made of polyethylene.

The technical result - an increase in the reliability of the cable under alternating temperatures by increasing the flexibility of the cable (small radius bending), small residual strain and insulation shell, high stability in close mounting under alternating temperature regimes with possible periodic cooling to minus 70 ^C. Cables can be used for installation of an onboard cable network of aviation and rocket and space technology.

Dynamically vulcanized olefin TECs are the most promising materials for insulation and cable protection due to the wide temperature range of operability, high physical and mechanical characteristics and increased resistance to aggressive environments. Dynamically vulcanized olefin TECs are obtained by intensive mechanical mixing of olefin rubber with an olefin thermoplastic while vulcanizing rubber during mixing. In this case, due to partial or complete vulcanization of the rubber phase using various vulcanizing systems (sulfuric, resin, peroxide, silane), it becomes possible to modify the physicomechanical and operational characteristics of materials. This is achieved due to the formation of a characteristic heterophase structure, which is a finely dispersed (submicron) vulcanized rubber phase in a continuous thermoplastic medium. During vulcanization of rubber, the melt viscosity of the mixture increases to maximum values. During intensive dynamic vulcanization, finely dispersed rubber particles of 1-2 microns in size are evenly distributed in the bulk of the thermoplastic. In this case, the material properties significantly change. According to their physical and mechanical characteristics, dynamically vulcanized TECs are close to rubbers, but, unlike them, new materials can be processed on thermoplastics equipment using waste-free technology.

The chemical industry produces a wide range of thermoplastic elastomers TEP of various characteristics and purposes, including raw materials for cable production. Ethylene-propylene-diene rubber is promising as an elastomer. Polypropylene is most often used as an olefin thermoplastic, however, it gives the cable sheath excessive rigidity. Polyethylene, a block copolymer of ethylene with propylene, may also be used. Sulfur, phenolic resins, organic peroxides, polyhydrosiloxanes are used as a vulcanizing additive.

The production of cable in a thermoplastic elastomeric sheath is associated with a number of technological difficulties, among which the difficulty of centering the sheath due to the greater fluidity of the melt (eccentricity), the heterogeneity of the sheath in thickness, and the difficulty of controlling the heating temperature over the extruder zones can be mentioned. In this case, the speed of extrusion and rewinding of a cable with a sheath of thermoplastic elastomer, in contrast to the rubber or PVC sheath, should be reduced due to the possible adhesion of the wound layers to each other. Modern materials and technologies make it possible to form a TPE shell without prejudice to other product characteristics.

In the claimed utility model, these problems are solved by selecting elastomer components, as well as experimentally determining the optimum temperature ranges in the heating zones.

The cable can be used for mounting the onboard cable network of aviation, rocket and space and military equipment, in arctic conditions, indoors and outdoors, in areas of direct access to solar radiation. In view of the specifics of close installation and operating conditions of cables of their design, in addition to the stability of electrical parameters during high-speed transmission of digital streams, they should have increased flexibility (small bending radius) and high resistance to deformation under alternating temperature conditions.

These requirements are met by a cable with new distinctive features relative to the prototype:

- insulation of conductors is made of polyethylene;

- the protective outer shell is made of thermoplastic elastomer (TPE) having high flexibility and high impact strength at low temperatures.

The production technology for the TEC shell is based on vulcanization of the elastomer during mixing with thermoplastics (three-dimensional dynamic vulcanization) or extrusion of the melt with subsequent cooling. During three-dimensional vulcanization, the shell is a dispersion of vulcanized micron particles of rubber (up to 80% of the volume of the thermoplastic), its properties are close to rubbers, but more plastic and resistant to deformations at low temperatures.

Table. The recommended temperature regime of the extruder of FIG. 2

Temperature in the zones of the cylinder: ° C values Zones Food area 90 Dosing area 110-120 Melting zone 130-145 Extrusion zone 160-165 Temperature on the forming head 170-175

In a specific embodiment, a styrene elastomer obtained by mixing polyolefins and block copolymers of styrene-ethylene-butylene-styrene (SEBS) can be selected as a thermoplastic elastomer.

In another specific embodiment, an elastomer obtained by dynamic vulcanization of a mixture of polyolefins and ethylene-propylene-diene rubber (international designation EPDM, when 1-2 mol% of dienes are added, is marked as SCEP) as a thermoplastic elastomer.

In particular cases, a mixture of polyolefins can be, for example, a mixture of polyethylene and polypropylene in equal or predominantly polyethylene mass fractions. The ratio of polyolefins is selected from the melt flow condition of the elastomer in the range (5 - 7) g / 10 min.

The relationship of the distinguishing features with the achieved technical result.

To transmit a signal, especially over long distances, it is important that the medium in which this signal flows has low dielectric losses, therefore, high-pressure polyethylene (LDPE) is mainly used as insulation for conductors. When used as an insulation material, block copolymers of propylene with ethylene, which is a polar dielectric, such losses are significant. According to Alpha Wire Company [3], for standard (without modifications) block copolymers, the dielectric loss tangent at a frequency of 1 MHz is 0.06–0.1, and increases with increasing signal frequency. At the same time, in the claimed cable for polyethylene according to [4], the dielectric loss tangent is normalized: no more than (3 - 4) · 10 ^-4 in the megahertz frequency range, and for thermoplastic elastomers the dielectric loss tangent is not more than 0.03 [5] ].

In contrast to the block copolymer used as a dielectric, polyethylene insulation is more flexible at low temperatures. Like a non-polar (neutral) dielectric, polyethylene consists of electrically neutral molecules and atoms that do not have electrical properties and do not affect the signal. In addition, it gives a smooth surface without roughness, which provides higher communication parameters required for efficient signal transmission.

Reference data for comparison: Polyvinyl chloride (PVC) - hardness HB = 15 - 16 according to Brinell, density ρ = 1.38-1.42 g / cm3; In the place of a bend it whitens; at low temperatures brittle, burns poorly, but emits chlorine products. Polypropylene (PP) - HB - 6 hardness, density ρ = 0.9 - 0.92, burns well. Low pressure polyethylene (HDPE) - hardness HB = 4.5 - 6, density ρ = 0.95-0.96, burns slowly with a bluish flame with fusion and polymer leakage. High pressure polyethylene (LDPE) - HB hardness = 1.5 - 2.5 according to Brinell, density ρ = 0.91 - 0.93, low water absorption (about 0.02% per month), high ductility, does not emit during combustion halogens.

Dynamic TECs have advantages over rubber, which is widely used in a number of analogues:

• the exclusion of a long energy-intensive stage of vulcanization;

• production is non-waste and environmentally friendly;

• the ability to obtain materials with a wide range of properties: from elastic to impact resistant;

• less material consumption (on average by 30%);

• wide temperature range of working capacity (frost resistance up to - 70 degrees),

• heat sealability of the shell;

• the possibility of processing on extruders used for plastics processing;

• significantly lower cost of finished products.

The unique properties of thermoplastic elastomers TEP are related to the peculiarity of their structure: the presence of microregions with different modules leads to easier relaxation and dissipation of temperature stresses, and also improves the resistance of the entire system to long-term loads. The formation of an elastic network due to the physical interactions of molecules after heat treatment allows them to be processed using methods used in the processing of thermoplastics.

In the dynamic vulcanization of thermoplastic elastomers, the method of crosslinking the elastomer when mixing the components is used. Optimal vulcanizing agents are selected empirically based on the available equipment and the specific purpose of the cable, for example, sulfur with the addition of metal oxides is used. The properties of the resulting shell are determined by the composition of the filler and the proportions of the components.

The EPDM elastomer has a very high resistance to low temperature and (if it is not filled with soot) excellent dielectric properties. EPDM has good mechanical properties and a very wide temperature range of application, elastic at low temperatures. Due to its rich structure, EPDM has very good resistance to ozone, atmospheric effects and aging.

TPE shells based on a mixture of polypropylene (PP) and ethylene-propylene-diene rubber (EPDM) during operation are somewhat inferior to shells made of vulcanized TPV elastomers in terms of strength and shape recoverability after deformation. At the same time, this class of materials is characterized by increased toughness and increased frost resistance.

Examples of raw material brands: ethylene-propylene synthetic rubber of the brand SKEPT CJSC Armatek, Supren (SK Group, South Korea), thermoplastic elastomers such as E3870, E3875 manufactured by Far East Group (China), EPDM-crumb produced by LLC Granulos ( Korolev city). Vulcanizing agents can be: sulfur, peroxides, metal oxides. You can enter a variety of mineral fillers, stabilizers and plasticizers.

In [6], dynamically vulcanized thermoplastic elastomers based on polyethylene and styrene-butadiene rubbers of various microstructures obtained by radical and ionic polymerization were investigated. The activity of several sulfur-accelerating systems in the process of dynamic vulcanization of the elastomeric phase was evaluated and it was shown that the process is most effective in the presence of a system containing a combination of a primary accelerator sulfenamide C and a secondary accelerator guanide F. According to the results of physical and mechanical tests, it was found that the optimal set of properties composites based on mortar styrene butadiene rubber VSL 2438 with an average content of 1,2 units and the highest content of styrene units.

The claimed cable with a TEC sheath can be used, in particular, for close installation (min R = 5D) in high-frequency digital communication systems operating in alternating temperature conditions, including deep cooling to minus 70 ° C.

An example of a specific implementation:

Symmetric high-frequency flexible flexible cold-resistant cables according to a utility model designed to transmit signals in the frequency range of use up to 100 MHz, tested by the applicant and showed suitability in a wider frequency range, up to 300 MHz. Protective shells made of dynamically vulcanized olefin thermoplastic elastomers have passed comprehensive temperature tests with positive results.

At the cable factory NPO FARIAL FARIAL.RU (Samara), pilot production of the product “cable high-frequency twisted-pair cable KSVPtp-KhL-5e” has been established. A cable without a shield, with a sheath made of cold-resistant TEP, can be shielded if necessary. Shell color is black.

Explanation of marking:

K - cable;

C - communication;

B - high frequency;

P - in polyethylene insulation;

TP - in the TEC shell;

HL - cold-resistant execution;

5e is a category.

Number of twisted pairs: 2x2x0.50; 4x2x0.52; 10x2x0.52; 16x2x0.52; 25x2x0.52.

Technical specification of cable KSVPTP-HL-5e:

The number of pairs and the diameter of the conductors, mm Diameter of a conducting core, mm Nominal outside diameter of a cable, mm Minimum bending radius The weight
cable
kg / km 2x2x0.5 0.5 ± 0.01 4.8 5D 22.45

Electrical Specifications:

Resistance of cores per 100m of cable length at a temperature of 20 ° C, Ohm, not more than 9.5;

Ohmic asymmetry lived in a working pair at a length of 100m no more than 2%.

Attenuation coefficient at a frequency of 100 MHz, calculated for a length of 100 m and a temperature of 20 ° C, dB, not more than 22.

The claimed device cable symmetric flexible cold-resistant for high-frequency communications meets the criteria of novelty and industrial applicability. In the available literature, there are no known technical solutions of the same purpose with a matching set of claimed essential features. The industrial applicability of the device is determined by the release of an experimental batch of cable with its demonstration at an industrial exhibition (Communication-2019, Moscow, April 23-26, 2019).

Advantages of the new cable:

- high manufacturability in manufacturing;

- high electrical characteristics;

- increased reliability under difficult operating conditions;

- wider scope.

Among the communication cables of the same purpose, in comparison with which the claimed technical result is achieved and which can be advantageously made according to the utility model, we can name symmetrical pair cables with copper conductors, with polyethylene insulation, in a sheath made of PVC compound, without a shield grades: KPVKG-100, KPVEKG-100, KVP-5e, KVPP-5e (U / UTP2-Cat5e and U / UTP4-Cat5e are marked according to ISO 11801), etc.

Cited literature

1. International standard ISO / IEC 11801 Information technology - Generic cabling for customer premises.

2 The use of polymeric materials in the cable industry, https://plastinfo.ru/information/articles/170

3. http://www.alphawire.com/pages/ 346.cfm

4. GOST 16336-77. Polyethylene compositions for the cable industry. Technical specifications

5. GOST 22372-77 (ST SEV 3164-81 and ST SEV 3166-81) Dielectric materials. Method for determination of dielectric constant and dielectric loss tangent.

6. Panfilova O.A., Wolfson S.I. et al. Effect of the composition of the vulcanizing group on the properties of dynamically vulcanized thermoplastic elastomers based on styrene butadiene rubbers and polyethylene. https://cyberleninka.ru/article/n/vliyanie-sostava-vulkanizuyuschey-gruppy-na-svoystva-dinamicheski-vulkanizovannyh-termoelastoplastov-na-osnove-butadien-stirolnyh.

Claims (5)

1. A symmetrical high-frequency cold-resistant cable, containing at least two twisted pairs of metal conductors having plastic insulation and enclosed in a protective outer sheath, with or without a shield, characterized in that the twisted pair cores have polyethylene (PE) insulation, and as the material of the outer shell used cold-resistant thermoplastic elastomer (TPE). 2. The cable according to claim 1, characterized in that the insulation of the twisted pair cores is made of cross-linked polyethylene. 3. The cable according to claim 1, characterized in that the vulcanized elastomer obtained by dynamic vulcanization of a mixture of polyolefins and ethylene-propylene-diene rubber (EPDM) is used as a thermoplastic elastomer. 4. The cable according to claim 1, characterized in that the styrene elastomer obtained by mixing the polyolefins and block copolymers of styrene-ethylene-butylene-styrene (SEBS) is used as a thermoplastic elastomer. 5. The cable according to paragraphs. 3, 4, characterized in that a polyethylene and polypropylene mixture with the content of polyethylene in equal or predominantly polyethylene mass fractions providing a melt flow rate of a thermoplastic elastomer in the range (5-7) g / 10 min at a temperature of 190 ° is selected as the mentioned polyolefins FROM.

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