Composition for electric insulation coating
The invention relates to electrical engineering, in particular compositions for the manufacture of coatings for electrical steels for magnetic circuits of electrical machines and devices. The objective of this invention is to provide a dielectric composition with high water and moisture resistance of electrical insulating coating while maintaining its high physical-mechanical properties. This object is achieved in that the sheet isotropic electrical steel is applied a composition containing, in wt.%: stabilized acrylic dispersion 24-40, phosphoric acid 29,4-37,0, magnesium oxide 2,6-3,5, aluminum hydroxide 1,21-2,00, boric acid 0,15-0,31, water the rest. 1 C. p. F.-ly, 1 table. The invention relates to electrical engineering, in particular to compositions for producing coatings on isotropic electrical steel for magnetic circuits of electrical machines and devices.Known insulating composition to obtain a coating on isotropic electrical steel , SU 1499577 A1, 1989, contains, wt%: Polyvinyl alcohol - 4,0-8,0 Phosphoric acid - 5,0-20,0 Polyoxyethylene ether - 0.1 to 1.5 magnesium Oxide, and 0.1 - 1.5 aluminum Hydroxide is 0.1 to 1.0 Boric acid - 0,02-0,2 Water - the Rest of the m to the claimed invention is a composition , EN 2120453 C1, 1996, contains, wt%: 46-47% latex of butadiene-styrene rubber - 36,0-37,5
Phosphoric acid - 28,0-29.3
Ethoxylated monoalkylphenols on the basis of the propylene - to 2.0-2.2
Magnesium oxide is 2.5-2.8
The aluminum hydroxide - 1,1-1,7
Boric acid - 0,14-0,25
Water - the Rest
The disadvantage of this structure is the low resistance of the insulating coating to the static action of water.The objective of this invention is to provide a dielectric composition with improved resistance to static action of water insulating coating while maintaining the high magnetic properties of steel and physico-mechanical properties of the coating.1. This object is achieved in that the sheet isotropic electrical steel is applied a composition containing, in wt.%:
Stabilized acrylic dispersion - 24-40
Phosphoric acid - 29,4-37.0
Magnesium oxide - 2,6-3,5
The aluminum hydroxide - 1,21-2,00
Boric acid - 0,15-0,31
Water - the Rest
2. The composition according to claim 1, wherein the stabilized acrylic dispersion is a mixture of acrylic dispersion and surfactants in a ratio of 17: 1.As surface-active substances ropylene, polyoxyethylene esters, polyoxy-etilenglikolevye ethers.The composition is prepared as follows. In the water download magnesium oxide, aluminum hydroxide, boric acid, phosphoric acid, dissolution is carried out at 90-100oC. After cooling the resulting solution is injected stabilized acrylic dispersion. The viscosity B3-4 at 20oWith 14-20 C.In all examples, the samples of isotropic electrical steel, processed within 5 s temperature 205oC. the Excess solution was removed by squeezing rubber rollers. The coating was subjected to heat treatment at a temperature of 480-580oC for 60 S.Specific magnetic losses and the magnetic induction is determined in the apparatus Epstein GOST 12119-80.Physico-mechanical properties of the coatings determined by the following properties: resistance to static action of water resistance.Resistance to static action of water is determined according to GOST 9.403-80 method A.The coefficient is determined according to GOST 9.074-77.The table shows the characteristics of the solution, the magnetic properties of steel and physico-mechanical properties of coatings obtained in the proposed solutions and the prototype.
Example 30 describes the properties of the solution of the prototype and of the coatings obtained in this solution.As can be seen from tables introduction stabilized acrylic emulsion leads to a decrease moisture absorption and to improve the moisture resistance of the coating at a temperature of 80oWith, while maintaining good physical and mechanical properties of coatings (examples 1,2,3).Thus, this object is achieved by the combination of all the characteristics claimed in the solution.Using the proposed structure provides the following benefits:
1. Increasing the resistance of insulating coatings to static action of water is very important in the operation of the products coated with insulating coating in wet conditions.2. This coating can be used for the manufacture of elements of the magnetic circuits of the motors used in the oil industry.3. The improvement of electromagnetic x is in asynchronous motors 20-100 kW
Sources of information
1. USSR author's certificate 1499577, N 01 In 3/18.2. Patent of the Russian Federation 2120453, 09 D 109/08 (prototype).
1. Composition for electric insulation coating on isotropic electrical steel, containing phosphoric acid, magnesium oxide, aluminum hydroxide, boric acid, characterized in that it contains a stabilized acrylic dispersion, in the following ratio, wt.%:
Stabilized acrylic dispersion - 2440
Phosphoric acid - 29,437,0
Magnesium oxide - 2,63,5
The aluminum hydroxide - 1,212,00
Boric acid is 0.150,31
Water - the Rest
2. The composition according to p. 1, wherein the stabilized acrylic dispersion is a mixture of acrylic dispersion and surfactants in a ratio of 17:1.
SUBSTANCE: coating includes following components, wt %: dispersed silica 75-89; magnesium oxide 10-20; colloid silica 1-3.
EFFECT: high electric resistance and maintaining magnetic properties of steel at acceptable level due to elimination of zone enriched with non-metallic inclusions in under-surface layers.
2 dwg, 2 tbl
SUBSTANCE: electrically insulating material for a high-voltage rotary machine consists of a base resin and powdered filler distributed in the base resin as the only filler, which is formed by plate-like aluminium oxide particles, wherein the powdered filler consists of particles with size of 0.002-150 mcm and volume ratio thereof ranges from 50% to 75%, preferably about 70%. The insulating paper for a high-voltage rotary machine contains said electrically insulating material. The insulating tape for a high-voltage rotary machine includes a carrier tape and an insulation paper tape, wherein the insulation paper tape is placed and attached onto the carrier tape.
EFFECT: improved electrically insulating material.
SUBSTANCE: invention refers to a method for production of a twisted elongated element, in particular, electrical cable, and self-twisted elongated element, in particular, electric cable, specifically designed for power transmission in wires, ropes and cables. A method for production of a self-twisted elongated element, in particular, an electric cable, is described based on application of at least one layer of polymer coating on an electric wire, wherein the outer layer (1) of the wire for power transmission (2) is made from a polymer composite of polyvinyl chloride and ferrite or neodymium in an amount of from 10% to 60% by weight, and subsequently the wire for power transmission (2) coated with an outer layer (1) is magnetized in a magnetic field where the magnetic field lines are located axially relative to the twisting element, wherein the magnetic induction is of at least 2 Tesla. Also the self-twisted elongated element is described.
EFFECT: self-twisted elongated element for power and signal transmission signal in wires and cables.
18 cl, 12 dwg, 9 ex