RU123573U1 - COMPACT UNINSULATED WIRE FOR ELECTRIC TRANSMISSION AIR LINES - Google Patents

Abstract

1. Compact non-insulated wire for overhead power transmission lines, consisting of a plastically crimped multi-wire steel core with a corrosion-protective metal coating and one or more concentric conductive strands of wires made of aluminum or aluminum alloy and filled with a graphite-based grease or without it, characterized by that the wires of conductive layers are made of aluminum or its alloys, modified with rare or rare-earth metals from the group: zirconium, scandium, yttrium, cerium, lanthanum, vanadium, hafnium or their mixtures. 2. Compact non-insulated wire for overhead power lines according to claim 1, characterized in that the wires of the conductive layers are made of heat-resistant aluminum alloys of the TAL or ZTAL brand, modified with zirconium. 3. Compact non-insulated wire for overhead power lines according to claim 1, characterized in that it contains a plastically compressed core of steel wires coated with aluminum or its alloys. Compact non-insulated wire for overhead power lines according to claim 1, characterized in that it contains a plastically compressed multi-wire core made of non-magnetic or low-magnetic steel. Compact non-insulated wire for overhead power lines according to claim 1, characterized in that the conductive layers are made sealed. Compact non-insulated wire for overhead power lines according to claim 1, characterized in that the internal conductive layers are made sealed, and the outer conductive layer is made conditionally hermetically sealed from shaped wires

Description

The utility model relates to electrical engineering, namely, to structures of non-insulated high-voltage steel-aluminum wires for overhead power lines.

The construction of steel-aluminum wire of the ASKP brand according to GOST 839-80, year of introduction 1981, consisting of a steel core providing mechanical strength of the wire, and one or more concentric conductive layers of round aluminum wires of the AVl brand according to TU 16-705.472-87, year of introduction 1987, is known. Russia. The core of the wire is twisted from galvanized steel round wires. The interwire space of the steel-aluminum wire of the ASKP brand is filled with neutral heat-resistant grease of the ZES brand according to TU 38 101474-74, year of entry 1974, Russia, for protection against corrosion.

Disadvantages of ASKP brand wire:

- increased diameter and weight;

- increased electrical resistance;

- reduced heat resistance;

- reduced current throughput;

- increased energy losses; - increased sag;

- increased drag coefficient;

- increased windage;

- increased mechanical load of the wire on the supports of power lines (power lines);

- reduced torsion resistance of the wire;

- increased vibration and dance of the wire;

- increased contact pressure between steel and aluminum wires and increased wire wear;

- reduced strength and durability;

- increased noise level;

- increased adhesion of snow and ice;

- increased permeability of water and pollution;

- reduced resistance of the wire to corrosion, lightning strikes, wind, snowfalls, ice.

In order to eliminate the above drawbacks, compact steel-aluminum wires have been developed containing a steel core and one or more concentric conductive wires of profiled aluminum or aluminum alloy wires.

The known design of a compact wire brand "Energy" (prototype) according to the patent of the Russian Federation No. 966442 for a utility model. This wire (Fig.) Contains a plastically crimped core twisted from steel wires 1 with a corrosion-resistant metal coating and one or more concentric conductive wires of profiled wires 2 of aluminum or aluminum alloy. The compact wire of the prototype is made using the following technology. The core of the wire is twisted on a twisting machine from one or more concentric coils of round steel wires in a spiral in alternating directions with a certain twisting pitch. In this case, one wire is placed in the center of the core. The core wires are made by drawing wire rod from carbon structural steel. A zinc coating of a certain thickness is applied to the steel wire. Plastic compression of the core is carried out by cold rolling using special carbide rollers. As a result of such compression, the cross sections of round steel wires accept mutually conjugated shaped profiles. Linear contact between the core wires develops in strip. The contact area increases and contact pressures decrease, the gaps between the wires are filled, and the structural stability of the core increases. The core becomes smoother and the shape rounded. In this case, the core diameter decreases by 10-15%, its strength increases by 5-10%, torsion resistance, wear resistance and durability, longitudinal elongation under load decreases. On top of the steel core, one or more concentric conductive sealed coils of aluminum or aluminum alloy are laid on a torsion machine in a spiral in alternating directions with a certain twisting pitch. The outer conductive wire can be twisted from shaped wires. Aluminum or aluminum alloy wires are also made by drawing. The interwire space of the wire is filled with electrically conductive graphite lubricant in the process of applying internal coils of aluminum wires.

The prototype wire has the following disadvantages:

- reduced long-term allowable heating temperature (up to 80 ° C);

- reduced long-term allowable load current.

The disadvantages of the prototype significantly reduce the operational characteristics and scope of bare wires for overhead power lines. The prototype wire with aluminum conductive layers cannot be used at heating temperatures above 90 ° C, because at temperatures above 90 ° C, existing grades of electrical aluminum and its alloys significantly lose their strength and become brittle. The use of existing heat-resistant aluminum alloys for bare wires is problematic due to their high electrical resistivity and low manufacturability.

The technical task of the utility model is the development of an uninsulated compact wire for overhead power lines with higher performance characteristics.

The technical result is achieved by the fact that the wires of the conductive coils are made of aluminum or its alloys modified with rare or rare-earth metals from the group: zirconium, scandium, yttrium, cerium, lanthanum, vanadium, hafnium, or mixtures thereof.

Common features of the prototype and the proposed technical solution are the presence of a plastically pressed steel multi-wire core with a corrosion-resistant metal coating and one or more concentric conductive layers of aluminum or aluminum alloy wires filled with graphite-based grease. At the same time, the proposed wire differs from the known one by the use of conductive fluff wires of aluminum or its alloys modified with rare or rare-earth metals from the group: zirconium, scandium, yttrium, cerium, lanthanum, vanadium, hafnium, or mixtures thereof.

Small additives (up to 1 wt.%) Of the above rare and rare-earth metals can significantly increase the strength, heat resistance and corrosion resistance of aluminum and its alloys without reducing electrical conductivity. For example, the addition of cerium in an amount of 0.5 wt.% Increases the strength and heat resistance of aluminum almost twice. This reduces corrosion by 10 times and significantly increases the electrical conductivity of aluminum. The addition of 0.3 wt.% Yttrium increases the conductivity of aluminum by 7.5%, and also increases its strength and heat resistance. The addition of 0.4 wt.% Scandium increases the strength of aluminum by 35%. This increases the electrical conductivity and heat resistance of aluminum. The addition of zirconium to 0.5 wt.% Allows you to significantly (2-2.5 times) increase the heat resistance of aluminum and its alloys without reducing electrical conductivity. Aluminum and its alloys modified with rare and rare-earth metals have practically no creep under load.

Advantages of the new wire:

- increased long-term allowable heating temperature (up to 210 ° C);

- increased long-term allowable load current (2-3 times);

- higher operational characteristics;

- increased reliability and durability;

- wider scope.

Restrictions on the choice of the brand of aluminum or aluminum alloy for conductive wire wires are imposed by the conditions for the manufacture, installation, dismantling and operation of the wire:

- manufacture of wire from wire rod by drawing method;

- long-term operation of the wire at temperatures up to 210 ° C;

- the required physical and mechanical characteristics of the wires: maximum breaking strength and elongation, minimum creep, minimum electrical resistance, maximum heat resistance, corrosion resistance and durability;

- price.

The above requirements are met by aluminum and its alloys modified with rare or rare-earth metals or mixtures thereof. The most affordable and cheapest are aluminum alloys modified with zirconium. The authors of the utility model suggest using wire rod made of heat-resistant aluminum alloys of the TAL or ZTAL brand according to international standards IEC 62004 L and ASTM B 941-05 modified with zirconium for the manufacture of conductive wire wires.

The manufacturing technology of the compact wire proposed by the authors of the utility model does not differ from the technology of manufacturing the wire according to the prototype. To increase the corrosion resistance of the wire, the steel wires of the plastic core can be coated with aluminum or its alloys. To reduce energy losses, the core wires can be made of non-magnetic or low-magnetic steel. In order to reduce the diameter of the wire, the conductive wires can be sealed. To ensure the tightness of the wire, the external conductive wire can be made of shaped wires of a Z-shaped or swept section.

The essence of the proposed utility model is illustrated by the following examples. Table 1 shows the options for wire samples for conductive coils of aluminum and aluminum alloy and their main characteristics. For the manufacture of wire used wire rod with a diameter of (9-9.5) mm:

- wire rod according to GOST 13843-78, Russia, from electrical aluminum grade A5E;

- wire rod in accordance with GOST 20967-75, Russia, from aluminum alloy of the ABE brand;

- wire rod made of heat-resistant TAL aluminum alloy according to international standards IEK 62004 L and ASTM B 941-05, modified with zirconium with a content of 0.18%;

- wire rod from heat-resistant aluminum alloy of the ZTAL brand according to international standards IEK 62004 L and ASTM B 941-05, modified with zirconium with a content of 25%.

Table 2 shows the main parameters and quality indicators of non-insulated steel-aluminum wires for overhead power lines:

- ASKP 185/29 grades in accordance with GOST 839-80, with a core made of galvanized steel round wires, conductive layers of AVl grade aluminum round wires and neutral ZES grease (analogue);

- ASKPU 185 / 21.5 Energy brands according to the patent of the Russian Federation No. 966442 for a utility model, with a plastic core of the POSs brand according to TU 3511-037-50289046-2010, year of entry 2010, Russia, from high-strength galvanized steel wires, sealed with conductive wires from aluminum wires of the AVl brand and conductive graphite grease of the SGEK brand according to TU 0254-035-50289046-2010, year of entry 2010, Russia, (prototype);

- ASKPTU 185 / 21.5 ELKA grades according to TU 3511-001-40914170-2012, year of entry 2012, Russia, with POSc grade plastic core made of high-strength galvanized steel wires, sealed with conductive wires from TAL heat-resistant aluminum alloy wires (option 1 ) and ZTAL (option 2), modified with zirconium (utility model) and conductive graphite grease of the SGEK brand.

From table 1 it is seen that the heat-resistant aluminum alloy of the ZTAL brand, modified with zirconium, has the best characteristics.

From table 2 it is seen that the new heat-resistant wire "Elka" have higher performance characteristics.

New compact uninsulated wires for overhead power transmission lines have been comprehensively tested at cable plants in the Russian Federation with positive results. Serial production of these wires is planned.

Table 1 Name Variants of samples of conductive wire Characteristics A5E Abe Tal ZTAL Tensile strength, MPa, according to GOST 10446-80 165 220 180 182 Elongation at break,%, according to GOST 10446-80 2 1,5 5,0 5.3 Electrical resistivity at 20 ° С DC, Ohm × mm ² / m, according to GOST 7229-76 0,0282 0,0300 0.0280 0,0278 The temperature of the onset of recrystallization, ° C 130 170 210 310 Creep limit at 200 ° С, MPa, according to GOST 3248-81 7 12 thirty 46

table 2 Key parameters and quality indicators for wires ASKP 185/29 brand wire (analog) ASKPU brand wire 185 / 21.5 (prototype) Options for heat-resistant wires "Elka" one 2 Wire diameter mm
Core diameter, mm Section, mm ² :
Aluminum
Steel The number of coils of steel wires one one one one Number of conductive coils 2 2 2 2 Number of conductive wire wires 26 21 21 21 Diameter of conductive wire wires, mm 2.98 3.4 3.4 3.4 Wire profile Round Round Round Round

Continuation of table 2

Key parameters and quality indicators for wires ASKP 185/29 brand wire (analog) ASKPU brand wire 185 / 21.5 (prototype) Options for heat-resistant wires "Elka" one 2 Conducting Powders Uncompressed Sealed Sealed Sealed Grade of aluminum (alloy) A5E A5E Tal ZTAL Brand of aluminum wires AVl AVl - - Grease ZES SGEC SGEC SGEC Mass of wire, kg / km 780 685 686 688 Breaking strength, N, according to GOST 839-80 62055 73933 76340 76475 Electrical resistance to direct current at 20 ° C, Ohm / km, according to GOST 839-80 0,1591 0.1550 0.1510 0.1515 Permissible load current. A, according to GOST R 51777-2001 510 600 900 1200 Long-term permissible wire heating temperature, ° С 80 80 150 210

Claims (6)

1. A compact non-insulated wire for overhead power transmission lines, consisting of a plastically pressed steel multi-wire core with a corrosion-protective metal coating and one or more concentric conductive layers of aluminum or aluminum alloy wires and filled with or without graphite-based grease, characterized in that that the conductive wire wires are made of aluminum or its alloys modified with rare or rare-earth metals from the group: circus s, scandium, yttrium, cerium, lanthanum, vanadium, hafnium, or mixtures thereof. 2. The non-insulated compact wire for overhead power transmission lines according to claim 1, characterized in that the conductive wire wires are made of heat-resistant aluminum alloys of the TAL or ZTAL brand modified with zirconium. 3. The compact non-insulated wire for overhead power lines according to claim 1, characterized in that it comprises a plastically crimped core of steel wires coated with aluminum or its alloys. 4. The compact non-insulated wire for overhead power lines according to claim 1, characterized in that it comprises a plastically crimped multiwire core of non-magnetic or low-magnetic steel. 5. The compact non-insulated wire for overhead power lines according to claim 1, characterized in that the conductive fluffs are sealed. 6. The non-insulated compact wire for overhead power transmission lines according to claim 1, characterized in that the internal conductive fluffs are sealed and the external conductive fluff is conditionally sealed from shaped wires.