Vacuum pressure impregnation

Vacuum pressure impregnation

1. improve the moisture resistance of the group around the line.

Due to the decrease of capillary porosity and the formation of a dense and smooth film on the surface, moisture is difficult to immerse in the interior of the insulating layer, so the moisture resistance is significantly improved. For example, the insulation resistance of the unpainted E-class insulated small motors decreases from 40M to 0.2M after 48 hours in humidity (relative humidity 95%-98%). However, the insulation resistance of the VPI-treated motors remains above 16M under the same conditions.

2. improve the electrical performance of the winding.

The electrical properties of insulating varnish are much better than that of air. For example, the breakdown strength of 1032 paint under normal condition is 70-90 kV/mm, while the breakdown strength of air under standard condition is only 33 kV/mm. After VPI treatment, the windings are bonded together and the air in the insulating layer is removed, so the initial free voltage and other electrical properties of the windings can be improved.

3. improve the heat resistance and thermal conductivity of the winding.

After insulation treatment, the heat resistance of natural organic fibers increased from grade Y to Grade A. The thermal conductivity of the baked insulating varnish is 0.14-0.6W/(m (, epoxy glue is 0.2-0.5W/(m (), and air thermal conductivity is 0.025-0.03W/(m (), after VPI treatment, the iron core, slot and inner void of the winding are filled with the paint, thus improving the thermal conductivity of the winding.

4. improving the mechanical properties of windings

After VPI treatment, the winding conductor is bonded to a solid whole, so the insulation layer loosening and wear caused by vibration, electromagnetic force and thermal expansion and contraction are improved.

5. improve the chemical stability of the winding.

After VPI treatment, the film can prevent the insulation material from directly contacting with harmful chemical media and damaging the insulation performance. It can also make the winding insulation capable of corona prevention and oil stain prevention.

The content of the article comes from the Internet. If there are any questions, please contact us.

Vacuum pressure