RU2705798C1 - Non-insulated steel-aluminum high-strength, high-temperature wire for overhead transmission lines - Google Patents

Abstract

FIELD: electrical equipment.SUBSTANCE: invention relates to the electrical equipment. High-strength, high-temperature non-insulated steel-aluminum wire comprises a steel core plastically deformed along the outer surface of the wires, a reduction degree of the cross-sectional area of core of 6–12 %, made of galvanized wires, density of zinc coating by coolant group, with time resistance to rupture, not less than 1,770 (180) N/mm(kgf/mm).EFFECT: invention allows increasing the efficiency of overhead transmission line by increasing the amount of electric power transferred per unit of time, reducing material and financial costs when executing air line projects.1 cl, 1 dwg

Description

The invention relates to the field of electrical engineering, namely to structures of non-insulated steel-aluminum wires, high-strength, high-temperature intended for the transmission of electrical energy through an overhead power line (VL) of 35 kV and above.

Known steel-aluminum wire, including the manufacture of a steel core from one central and six galvanized steel wires twisted around it with a diameter of 2.2 ÷ 3.6 mm each, applying an annular layer of extruded aluminum to the steel core on the press, cooling with water at a distance of at least 1.5 m from the aluminum pressing zone and winding the finished wire onto the receiving drum (see the description of the invention to RF patent No. 2351486; IPC В60М 1/13 published on April 10, 2009).

The disadvantages of this wire are:

- the use of a steel core in a steel-aluminum wire in the form of a round carbon steel wire of low-carbon thermally untreated, second class according to GOST 3282 (this standard applies to round low-carbon steel wire intended for the manufacture of nails, bonding, fencing and other purposes) does not contribute to the maintenance of specified performance properties wires, due to the low temporary resistance to rupture of the wire, and the steel core as a whole;

- a special operation is required to prepare the surface of the steel wire for applying aluminum;

- a rather complex design to eliminate bumps on the surface of a round steel wire

Known three-lead wire for overhead power lines, contains a core, on top of which there are midi with round aluminum wires, at least one winding contains steel wires (see the description of the invention to patent SU No. 1791854, IPC Н01В 5/04, 5/08, published on 30.01 .93. Bull. No. 4).

The disadvantages of the known three-drinkable wire are:

- the technological complexity of manufacturing a wire from a set of wires with a large difference in the mechanical properties of the wires;

- the use of three-drunk wires on overhead power lines with a steel wire to aluminum ratio of 1: 5 does not contribute to an increase in mechanical strength to the parameters of steel wires;

the use of aluminum wires in the construction increases the cost of the wire;

low technical resource due to the use in the design of point contact of round wires in a wire of type TK (twisting of coils in opposite directions);

suboptimal working section of the conductor due to the large air gaps between the round wires in the structure, (reduces the tensile force and reduces the total electrical resistance of the wire as a whole).

A wire is known for overhead power lines containing coils of steel aluminum-clad wires, characterized in that the thickness of the clad aluminum layer on the surface of the steel wire is in the range (0.02 ÷ 0.5) mm in such a way that the wire has an electric current throughput of (0.8 ÷ 8) amperes per square millimeter of its cross section at the maximum allowable surface temperature of the wire equal to 250 ° C. (see the description of the invention to the patent of the Russian Federation No. 2396617, IPC НВВ 5/04, published on 08/10/2010).

A disadvantage of the known wire is:

- with the indicated thickness of the clad aluminum layer on the surface of the steel wire, in order to obtain the required cross-sectional size of the aluminum wire, a significant increase in the number of wires in this wire design is necessary, which leads to an increase in its diameter and weight in relation to the currently known wires for overhead lines . With given sag arrows, wind and ice loads, increased loads are created on the support elements, for which existing supports may not be designed. Therefore, it may be necessary to strengthen them, to install additional intermediate supports in the spans of an overhead line, or to install new (replace existing) supports.

Known compact non-insulated wire for overhead power lines (see the description of the patent for utility model RU No. 96442, IPC НВВ 5/00, published July 27, 2010).

The technical result is achieved by the fact that, as a steel core, the wire contains a plastically crimped core of round galvanized steel wires according to GOST 9850-72. The manufacture of a plastically crimped core, according to the authors, contributes to increased stiffness and strength of the core and wire, but the galvanized steel wire according to GOST 9850-72 used for the manufacture of the core does not meet these requirements. Plastic reduction, as a type of processing, increases the density of the strand and increases the strength of the core, but using the above wire made in accordance with GOST 9850 72, it is not possible to achieve an increase in the claimed strength.

The aluminum wires of the shaped profile of the Z-shaped profile used in this design increase the complexity in manufacturing, the cost of construction.

A manufacturing option for multidirectional aluminum layers from a round wire followed by plastic deformation of the upper layer reduces the vibration resistance of the structure and reduces the technical resource by forcing the outer layers of the wires into the inner ones and thinning the latter

A known method of manufacturing a steel-aluminum wire, which includes the manufacture of a steel core providing mechanical strength of the wire, from galvanized steel wires with a diameter of 1.50 ÷ 4.61 mm each, coating the core with a layer of protective heat-resistant grease and manufacturing one or more windings of aluminum wires (see. Technical GOST 839-80 “Non-insulated wires for overhead power lines).

The disadvantages of this known method include the following:

- reduced mechanical strength;

- reduced throughput, increased heating;

- increased vibration of the wire under the influence of wind, increased windage;

- increased adhesion of snow and ice, increased formation of ice deposits;

- the temperature limit of heating by passing current during long-term operation is not more than 90 ° C, at a temperature of 100-110 ° C, the current-carrying coil of the wire loses its strength, which limits the possibility of transmission by the wire and by the amount of electric energy transmitted (current value), since its destruction begins and (or) the size of the deflection boom becomes greater than the permissible value determined by the rules for the safe operation of high-voltage lines.

The aim of the invention is the creation of non-insulated steel-aluminum wire of two types: high-strength, and high-strength high-temperature, the use of the resulting wire design for the transmission and distribution of electrical energy to a nominal voltage of 35 kV and above, with a nominal frequency of 50 Hz.

The invention consists in the following.

According to the first type.

High-strength non-insulated steel-aluminum wire contains a steel core plastically deformed along the outer surface of the wires, a compression ratio of the core cross section of 6-12%, made of galvanized wires, the density of the zinc coating in the coolant group, with a temporary tensile strength of at least 1770 (180) N / mm ² (kgf / mm ² ) according to GOST 7372-79 "Steel wire rope. Technical conditions. " Conductive wires, one of the aluminum wires of trapezoidal cross-section and one outer wire of round aluminum wires plastically deformed along the outer surface of the wire. The conductive fluffs are made in the opposite direction. The steel core is coated with a 0.3: 0.7 mm thick lubricant layer that is resistant to high temperatures.

The invention is illustrated in the drawing, where in (Fig. 1), around a galvanized steel core 1, made with a linear touch of the wires in layers, the outer surfaces of the wires are plastically deformed along the outer surface of the wires, the compression ratio of the core cross section is 6-12%.

Around the core there are multidirectional successive coils, one coiled from aluminum wires of trapezoidal shape 2 and one coiled from aluminum wires of round shape 3, the outer surfaces of aluminum wires are plastically deformed, the degree of compression of the cross-sectional area of the wire is 12-14%.

This allows, using a new design of a high-strength metal core for uninsulated wires, a galvanized wire in the coolant group with a temporary resistance of at least 1770 (180) N / mm ² (kgf / mm ² ), a method of manufacturing a core to increase its strength with respect to steel the core of steel-aluminum wire according to GOST 839-80, in which the steel core is made of round galvanized wires, made in accordance with the requirements of GOST 9850, the strength characteristics of which are approximately 35-40% lower than the strength characteristics of galvanized wire made in accordance with the requirements of GOST 7372-79.

Multidirectional conductive coils made of one coil of trapezoidal aluminum wires and one coil of round aluminum wires, plastically deformed along the outer surface of the wire, contribute to a decrease in DC electrical resistance and an increase in wire throughput.

According to the second type, non-insulated steel-aluminum wire is high-strength, high-temperature contains a steel core made with a linear touch of the wires in layers, plastically deformed along the outer surface of the wires, the degree of compression of the core cross-sectional area is 6-12%. The core is made of galvanized wires, the density of the zinc coating according to the coolant group, with a temporary tear resistance of at least 1770 (180) N / mm ² (kgf / mm ² ) according to GOST 7372-79 “Steel wire rope. Technical conditions. " Multidirectional conductive fluffs made of an aluminum-based alloy, including zirconium 0.20 ÷ 0.40 weight. %, in which the wire is made of a trapezoidal cross-section and one twist of round wires, plastically deformed along the outer surface of the wire, the degree of compression of the cross-sectional area of 12-14%.

For high-strength, high-temperature uninsulated steel-aluminum wire, the design of the galvanized metal core 1 and its manufacturing technology are similar to the construction of a steel metal core for high-strength non-insulated steel-aluminum wire.

The steel core is coated with a layer of lubricant with a thickness of 0.3 ÷ 0.7 mm, resistant to high temperatures.

On top of the lubricant layer, conductive multidirectional powders are sequentially arranged, made of an aluminum-based alloy, including zirconium 0.20 ÷ 0.40 weight. % trapezoidal wires 2 and one twist of round wires based on aluminum alloy 3, including zirconium 0.20 ÷ 0.40 weight. %, plastically deformed along the outer surface of the wire, the degree of compression of the cross-sectional area of 12-14%.

This makes it possible to use the newly developed high-strength, high-temperature wire for transmission and distribution of electric energy to a rated alternating voltage of 35 kV and higher, with a nominal frequency of 50 Hz, allowing a working temperature of the wire of 210 ° C at maximum values of the transmitted current, which will significantly increase the efficiency of overhead lines for by increasing the amount of electricity transmitted per unit time, to reduce material and financial costs when performing overhead line projects in areas with difficult geographic and meteorological conditions; carry out reconstruction projects of power lines with an increased level of environmental safety.

On newly constructed overhead lines, the use of the proposed high-strength, high-temperature wires will significantly reduce accident rate due to increased resistance to climatic influences (ice and wind), as well as reduce the cost of overhead lines by increasing the span lengths and reducing the number of intermediate supports.

Claims (1)

Non-insulated steel-aluminum wire high strength, high temperature for overhead power lines, containing a steel core with a linear touch of galvanized steel wires, the outer surfaces of the core wires are plastically deformed, the degree of compression of the core cross-sectional area is 6-12%, the steel core is coated with a lubricant layer of 0.3 ÷ 0.7 mm, resistant to high temperatures, around the core are sequentially multidirectional coils of aluminum or aluminum alloy the yuminium of trapezoidal and circular wires, the outer surfaces of the round wires are plastically deformed, the degree of compression of the cross-sectional area is 12-14%.

Images