Insulation treatment method of induction melting furnace coil

1. For the 380V incoming line voltage, the voltage across the coil is 750V, and the inter-turn voltage is also tens of volts. If the distance between the turns is large enough, the distance between the turns can also be used as insulation. This is the early insulation treatment. If steel slag splashes on the coil, it will form a short circuit between turns. This method has now been eliminated.

2. The current commonly used insulation treatment process for induction melting furnace coils is four insulation treatment methods. First, spray insulating paint on the surface of the coil; secondly, wind a layer of mica tape on the coil that has been sprayed with insulating paint; again, wind a layer of glass ribbon on the outside of the mica tape; finally, spray a layer of insulating paint. Such an insulation treatment process can ensure that the insulation withstand voltage of the induction melting furnace coil is as high as 5000V.

3. Another method of insulation treatment for induction melting furnace coils is to spray high-temperature insulating paint directly. Some commonly known insulating paints can withstand a temperature of 1800°C, but spraying high-temperature insulating paint is also a simple method. Theoretically speaking, the higher the insulation grade of the high-temperature insulating paint, the higher the temperature resistance of the insulating paint, and the high volume resistivity of the high-temperature insulating paint is greater than 1016Ωm at room temperature. High dielectric strength (breakdown strength), greater than 30KV/m. It has good chemical stability, aging resistance, corrosion resistance, and good soothing reactivity. No flash point, ignition point, high hardness, hardness greater than 7H. Heat-resistant 1800℃, can work under open flame for a long time.

4. Whether the insulation of the induction melting furnace coil is the distance between the turns, or the winding of insulating materials or spraying of high-temperature insulating paint, it is believed that a layer of refractory mortar should be applied to the inside of the coil and between the turns of the coil.

Coil refractory mortar is used for the coil of induction melting furnace. It is evenly smeared on the surface and ramp, which has a good insulation effect. It can prevent the short circuit or discharge of the coil from generating excessive impulse current to burn the thyristor, etc., and effectively prevent the thyristor from burning due to The coil is aging and the coil ignites caused by water leakage, which can effectively prevent the furnace from being worn due to the excessively high temperature of the molten steel.