The enameled wire insulation materials commonly used by electricians can be divided into inorganic materials, organic insulation materials and mixed insulation materials according to their chemical properties.(1) Inorganic insulating materials: mica, asbestos, marble, porcelain, glass, sulfur, etc., mainly used for motor and electrical winding insulation, switch bottom plates and insulators.(2) Organic insulating materials: shellac, resin, rubber, cotton yarn, paper, hemp, silk, rayon, most of which are used to make insulating varnish and coating insulation for winding wires.(3) Mixed insulating materials: various shaped insulating materials processed from the above two materials, used as the base and shell of electrical appliances.2. Performance indicatorsThe performance indicators of enameled wire insulation materials commonly used by electricians are insulation strength, tensile strength, specific gravity, expansion coefficient, etc.(1) Withstand voltage strength: When the electric field strength increases to a certain limit, the insulating material will break down. The electric field strength of this insulation breakdown is called the dielectric withstand voltage strength, which is usually expressed in the KV value of the voltage that a 1mm thick insulating material can withstand.(2) Tensile strength: the tensile force that the insulating material can withstand per unit cross-sectional area, for example, the glass can withstand 140 per square centimeter of cross-sectional areakilogram.(3) Density: The mass of insulating material per cubic meter of volume, for example, sulfur has 2 grams per cubic meter of volume.(4) Expansion coefficient: the degree to which the insulator increases in volume after being heated.3. Heat resistance grade of enameled wire insulation material(1) Y gradeInsulation materials: natural textiles such as wood, cotton, and fibers, textiles based on cellulose acetate and polyamide, and plastics that are easy to decompose and have a low melting point.Maximum operating temperature: 90 degrees.(2) A GradeInsulation materials: Y-grade materials that work in mineral oil and impregnated with oil or oleoresin compound glue, insulation and oil-based paint for enameled wire, varnished cloth, and varnished wire. Asphalt paint, etc.Maximum operating temperature: 105 degrees.(3) E GradeInsulation materials: polyester film and Class A material composite, glass cloth, oily resin paint, polyvinyl acetal high-strength enameled wire, vinyl acetate heat-resistant enameled wire.Maximum operating temperature: 120 degrees.(4) B GradeInsulation material: polyester film, mica, glass fiber, asbestos, etc. impregnated with suitable resin bonding, polyester paint, polyester enameled wire.Maximum operating temperature: 130 degrees.(5) F GradeInsulation materials: mica products reinforced with organic fiber materials, glass filaments and asbestos, glass wool cloth, laminated products based on glass filament cloth and asbestos fibers, mica powder products reinforced with inorganic materials and stone belts, chemical heat Polyester or alkyd materials with good stability, composite silicone organic polyester paint.Maximum operating temperature: 155 degrees.(6) H GradeInsulation materials: mica products without reinforcement or inorganic materials as reinforcement, thick F grade materials, composite mica, organic silicon mica products, silicon organic paint, silicon organic rubber, polyimide composite glass cloth, composite film, polyamide Imine paint etc.Maximum operating temperature: 180 degrees.(7) C GradeInsulation material: Inorganic materials that do not use any organic adhesive grade immersion agent, such as quartz, asbestos, mica, glass and electric porcelain materials.Limit working temperature: above 180 degrees.