Selection of insulation paper type and thickness of motor and installation cleaning method


Release time:

2023-05-31

Class A insulation contains organic fiber materials such as cotton yarn, silk, paper and the like treated by impregnation and enamel on the usual enameled wire. Currently only used in transformers. The allowable working temperature of Class A insulation is 105 ℃.

1. Motor insulation paper type

Motor insulation paper commonly used in motors is divided into six grades: A, E, B, F, H and C according to its heat resistance.

1. Class A insulation contains organic fiber materials such as cotton yarn, silk, paper and the like treated by impregnation and enamel on the usual enameled wire. Currently only used in transformers. The allowable working temperature of Class A insulation is 105 ℃.

2. Class E insulation includes films made of polyester resin, epoxy resin, triacetate fiber, etc., and enamel on polyvinyl acetal high toughness enameled wire. Used in medium and small AC and DC motors. The allowable working temperature of class E insulation is 120 ℃.

3. Class B insulation includes materials and compositions made of inorganic materials such as mica, asbestos, glass filament and the like with organic paint or resin (treated with heat resistance) as adhesive, enamel on polyester high toughness enameled wire, etc. General large and medium-sized synchronous machines and medium and small AC and DC motors. The allowable working temperature of class B insulation material is 130 ℃.

4.F class insulation contains mica, asbestos, glass fiber and other inorganic materials modified with silicon organic compounds of synthetic resin paint, or heat resistance to meet the requirements of this level of alkyd, epoxy resin as a binder made of materials or their combinations. The allowable working temperature of class F insulation is 155 ℃.

5.H class insulation contains silicon organic matter and its mica, asbestos, glass fiber and other inorganic materials with silicon organic paint as a binder made of materials. Mainly used in the requirements to minimize the size, reduce the weight of the occasion, such as aviation motor, crane motor traction motor, etc. The allowable working temperature of H-grade composite insulation paper is 180 ℃.

2. Motor insulation paper thickness and kilowatt ratio

First of all, it needs to be clear that the paint film on the copper wire is usually in line with the insulation conditions, but due to the production, transportation, wire, drying and heating conditions, it is inevitable that the paint film will fall, and then need to further insulation paper insulation. Secondly, there is no fixed value for the selection of the thickness of the insulating paper, and the general principle is that the thicker the better without increasing the difficulty of embedding the wire. Next, the article collected some information about the thickness of the motor insulation paper and the ratio of kilowatts, for reference only.

Netizen 1: According to the power of the motor, it is usually 0.17mm thick for the motor insulation paper below 10 dry watts, and it is appropriate to 0.21 the insulation paper above 10K watts.

Netizen 2: The center height of the motor is 80-112mm, and the thickness of the motor insulation paper is about 0.25mm; The center height is 132-160mm, and the thickness of the motor insulation paper is about 0.3mm; The center height is 180-280mm, and the thickness of the motor insulation paper is about 0.35mm.

General standard: the thickness of the insulation paper should be as thick as possible to ensure the insulation performance of the motor and prevent the occurrence of motor heating, burning and short circuit. The selection of insulating paper requires consideration of the installation environment of the motor, such as humid environment to choose moisture-resistant insulating paper; the heat-resistant temperature of the insulating paper should also meet the requirements of the motor.