System and method for applying varnish to an electrical coil

摘要

A polyurethane varnish is used to impregnate an electrical coil and cure it. The impregnation and curing treatment method comprises a preliminary heating step in which an article having a coil is heated to a preliminary heating temperature at which the viscosity of the polyurethane varnish decreases and is above the drying temperature, a varnish application step in which the polyurethane varnish is continuously applied to the coil while rotating the heated article at a constant speed, and a high-temperature rotary drying step in which the polyurethane varnish is dried while heating said polyurethane varnish at a drying temperature which is higher than the varnish temperature during the varnish application step.