Coil varnish manufacturer
Coil impregnating varnish is an important process in the electrical and electronics sectors that aids in improving the performance, reliability, and life of electric coils. Coils, being a bundle of wire wound upon each other, are the center of most electrical devices such as transformers, inductors, and motors.
Yet the minute gaps and spaces between each of the constituent individual wires are the points of weakness in the insulation system and can be subject to electrical discharge, heat buildup, and environmental contamination. Coil impregnating varnish is specifically designed to infiltrate these coils and fill all the voids with a homogenous, integral mass. It is usually achieved via vacuum-pressure impregnation (VPI) so that there will be deep penetration and extensive saturation.
The main role of impregnation varnish is to give good electrical insulation. In the filling of the air voids, it enhances the dielectric strength of the coil overall, imparting resistance to electrical breakdown and short circuiting. This is especially critical when working in high voltage systems where arcing can be an enormous problem.
The varnish also imparts good mechanical support. It holds the coil wires firm so that they will not vibrate or move when the device is in operation. This mechanical rigidity functions as a buffer against the stresses caused by electromagnetic forces and thermal expansion otherwise resulting in damage and premature failure of the insulation. The hardened varnish also enhances thermal conductivity, enabling dissipation of heat more efficiently from the coil center and preventing overheating. Lastly, the varnish is a combatant shield against water, chemicals, and contaminants that will rust the wires and cause the insulation to drain. In essence, coil impregnation varnish takes a group of wires and makes them one very tough, reliable part that is ready to withstand the brutality of their operating condition.
