Insulation material classification and performance index

1, the classification of electrical insulation materials commonly used in accordance with its chemical nature, can be divided into inorganic materials, organic insulating materials and mixed insulating materials.

(1), inorganic insulating materials: Mica, asbestos, marble, porcelain, glass, sulfur, etc., mainly for motor, electrical winding insulation, switch bottom and insulators.

(2) Organic Insulating Materials: There are shellac, resin, rubber, cotton yarn, paper, hemp, silk, and rayon, which are mostly used for the manufacture of insulation coatings, insulating coverings for winding wires, and the like.

(3), mixed insulation material: a variety of molding insulation materials made of the above two kinds of materials, used as electrical base, shell and so on.

2, performance indicators Electrical performance parameters commonly used in insulating materials such as dielectric strength, tensile strength, specific gravity, expansion coefficient and so on.

(1) Compressive strength: In the electric field, the insulating material breaks down when the electric field strength increases to a certain limit. The electric field strength of this insulation breakdown is called the dielectric strength (also called dielectric strength or dielectric strength), and is usually expressed as a voltage KV value that a 1 mm thick insulating material can withstand.

(2) Tensile strength: The tensile force per unit sectional area of ​​the insulating material can withstand, for example, the glass can withstand 140 kilograms per square centimeter of cross-sectional area.

(3) Density: The mass per cubic meter of insulation material, for example 2 grams per cubic meter of sulfur.

(4) Coefficient of expansion: The extent to which the insulator increases in volume after it is heated.

3. Heat-resistant grades of insulating materials (1) Class Y insulating materials: natural textiles such as wood, cotton, and fibers, textiles based on acetate and polyamide, and materials that are easily decomposed and have a low melting point.

Extreme operating temperature: 90 degrees.

(2) Class A insulating materials: Grade Y materials impregnated with mineral oils and impregnated with oil or oleoresin composites, insulation of enameled wire, varnished cloth, lacquer, and oil paint. Asphalt paint and so on.

Limit working temperature: 105 degrees.

(3) Class E insulating materials: Polyester film and A-grade material composite, glass cloth, oil-based resin paint, polyvinyl acetal high-strength wire, vinyl acetate heat-resistant wire.

Extreme operating temperature: 120 degrees.

(4) Class B insulation material: polyester film, impregnated mica, glass fiber, asbestos, etc., with appropriate resin, polyester paint, polyester enameled wire.

Extreme operating temperature: 130 degrees.

(5) Class F insulation materials: mica products reinforced with organic fiber materials, glass wool and asbestos, glass wool cloth, laminated products based on glass wool cloth and asbestos fiber reinforced with inorganic materials as reinforcement and stone belts Mica powder products chemical thermal stability better polyester or alkyd materials, composite silicone organic polyester paint.

Limit working temperature: 155 degrees.

(6) Class H insulating materials: mica products without reinforcement or reinforcement with inorganic materials, thickened F-class materials, composite mica, silicone mica products, silicon organic paint silicone organic rubber polyimide composite glass cloth, Composite film, polyimide paint and so on.

Limit working temperature: 180 degrees.

(7) Class C insulating materials: Inorganic materials that do not use any organic binder and agent grade infusions, such as quartz, asbestos, mica, glass, and electric porcelain materials.

Limit working temperature: 180 degrees or more.