Why is the motor inseparable from insulation paint?

The motor and insulation paint are inseparable. The composition and manufacturing technology of insulation paint have been constantly updated and improved, promoting the rapid development of motor design and manufacturing methods and means, and promoting the widespread application of high-temperature, high-power density motors that were originally confined to the design zone.

It can be seen from this that insulation paint is extremely important for motors. Motor insulation paint can be roughly divided into five categories according to its scope of use: impregnating paint, enameled wire paint, covering paint, silicon steel sheet paint, and anti corona paint. Among them, anti corona paint is generally only used on high-voltage motors.

Impregnating paint

Immersion paint can be divided into two categories: solvent paint and solvent-free paint. It is mainly used to impregnate motor windings (stator windings and wound motor rotor windings) to fill their gaps and micropores. After curing, it can form a continuous and smooth paint film on the surface of the winding and solidify it into a hard whole.

Immersion and drying are particularly critical steps in the production process of motors, and the viscosity, flowability, solid content, dryness, and adhesion of impregnating paint directly affect the final performance of the motor.

Enameled wire paint

Enamel wire is the most common electromagnetic wire in motors, and enamel wire paint is mainly used for coating and insulating the enamel wire core. Due to the heat, chemical, and various mechanical forces that wires undergo during winding, embedding, and other processes, it is required that enameled wire paint has good coating properties (i.e., can be uniformly coated), strong adhesion of the paint film, smooth and soft surface with toughness, certain wear resistance and elasticity, good electrical performance, heat resistance, solubility resistance, and no corrosion to conductors.

Motor manufacturers should pay special attention to the control of enameled wires. Some motor manufacturers are equipped with necessary testing equipment, and tests such as film continuity, twisting and peeling, scratch resistance, and voltage resistance can effectively verify the overall performance of the film.

Covering paint

Covering paint is used to coat impregnated coils and insulating components, forming a uniformly thick insulation protective layer on their surface to prevent mechanical damage to equipment insulation and corrosion from atmospheric and chemical substances, and to improve surface insulation strength. Therefore, it is required that the covering paint has the characteristics of fast drying, strong adhesion, hard paint film, high mechanical strength, moisture resistance, oil resistance, corrosion resistance, etc.