The role of the motor winding dipping _ the method of dipping the motor winding

The role of motor winding dipping paint

1. Improve the heat resistance and thermal conductivity of winding insulation

Before dipping, the winding insulation gap is filled with air, and the thermal conductivity is poor. After dipping, the insulating paint fills all the voids of the winding insulation, and the thermal conductivity is greatly enhanced. After the paint film is formed on the dipped part, the contact with the air is reduced, the oxidation process is delayed, and the heat resistance is also improved.

2. Improve the electrical properties of winding insulation

After dipping, the winding turns, the gaps between the phases and the insulating layer and the interior of the insulating material are filled with insulating paint, which basically eliminates air bubbles and forms solid insulation with strong pressure resistance, thereby improving the electrical performance of the winding insulation. .

3. Improve the moisture resistance and chemical stability of winding insulation

Moisture and moisture can age and deteriorate the insulating material prior to dipping. After dipping, the insulating paint fills the capillaries and gaps of the insulating material, and forms a smooth paint film, which makes it difficult for moisture and moisture to penetrate, and dust and corrosive gases cannot directly contact the winding. And the winding insulation treated with special dipping paint also has the functions of anti-dew, anti-corona, anti-corrosion and anti-oil pollution.

4. Improve the mechanical strength of the winding

After dipping, each wire of the winding is bonded into a solid whole, which strengthens the mechanical strength of the winding and reduces the loosening and abrasion of insulation caused by electromagnetic force, vibration, thermal expansion and contraction.


1. Dipping

When repairing a single motor, the winding dip can be dipped. When pouring, place the stator vertically on the paint dripping tray, with one end of the winding facing upward, and use a paint pot or paint brush to paint the upper end of the winding. When the winding gap is filled with paint and begins to seep out from the other end of the gap, the stator is turned over and the other end of the winding is poured. until poured. This method can reduce the waste of insulating paint when repairing small motors sporadically.

2. Drip dip

This method is suitable for dipping treatment of small and medium-sized motors. Units lacking special equipment can use hand-painting process. The following introduces a common dripping process for dipping of small motor windings.

①Recipe. 6101 epoxy resin (mass ratio), tung oil maleic anhydride 50%, ready to use.

②Preheating. Power on and heat the winding for about 4 minutes, and control the temperature between 100 and 115 °C (measured with a spot thermometer), or place the winding in a drying oven and heat it for about 0.5 hours.

③ drip dipping. Place the stator of the motor vertically on the paint tray. When the temperature of the motor drops to 60-70°C, start to drip paint manually. After 10 minutes, turn the stator over and dip the other end of the winding until it is completely poured.

④ curing. After drip dipping, the winding is energized and cured, and the winding temperature is kept at 100-150 °C; the insulation resistance value is measured to be qualified (20MΩ), or the winding is heated in a drying furnace, the temperature is the same as above, and the time is about 2h (depending on the size of the motor), Released when the insulation resistance exceeds 1.5MΩ.

3. Rolling paint

This method is suitable for dipping of rotor or armature windings. When rolling paint, pour insulating paint into the paint tank, place the rotor in the paint tank, and the paint surface should submerge the rotor winding for more than 200mm. If the paint groove is too shallow and the rotor winding has a small area to be dipped in paint, the rotor should be rolled several times, or the rotor should be brushed while rolling. Usually rolling 3 to 5 times, the insulating paint can be soaked into the insulation.

4. Immersion

When repairing small and medium-sized motors in batches, the winding dipping paint can be immersed. When immersed, first put an appropriate amount of insulating paint into the paint can, and then hoist it into the motor stator, so that the paint liquid floods the stator for more than 200mm. After the lacquer liquid penetrates all the gaps between the winding and the insulating paper, the stator is lifted to drip the lacquer. When dipping paint, add 0.3~0.5MPa pressure. The effect is better.

5. Vacuum pressure dip

For high-voltage motors, as well as small and medium-sized motors that require high insulation quality, their windings can be dipped in vacuum pressure. When dipping paint, place the stator of the motor in a closed paint container, and use vacuum technology to remove moisture. After the winding is dipped in paint, a pressure of 200-700kPa is applied to the paint surface, so that the paint liquid penetrates into all the gaps of the winding and the depth of the capillary holes of the insulating paper to ensure the quality of the dipping paint.

After dipping the paint, place the stator on the wire mesh to make the paint drip clean, and wipe off the paint film on the surface of the stator iron core and the outer surface of the machine base with a cotton cloth dipped in gasoline, so as not to reduce the air gap and affect the assembly of the rotor.

After the winding is dipped and dried, the paint film in the inner cavity of the iron core cannot be removed with a wire brush. Otherwise, once the wire on the wire brush is broken, a small piece of wire head may fall on the notch of the iron core, especially when the wire brush is inserted into the edge of the slot wedge, if any broken wire remains, even with compressed air It can’t be blown off, and when the motor is running, the residual wire ends can scratch the rotor. Therefore, it is forbidden to use a wire brush to remove the paint film of the inner cavity of the iron core.

The Links:   ESM4016 2MBI150UM-120-50