METHOD AND HEATER FOR UNIFORMLY CURING A RESIN IMPREGNATED ELECTRICAL BUSHING

摘要

Method and heater for uniformly curing a resin impregnated electrical bushing. The method comprises precuring a resin impregnated wound structure of the bushing by heating simultaneously equal sections of the wound structure from bottom to top of the wound structure internally through the hollow conductor at progressively reducing temperatures from bottom to top sections of the wound structure starting with a temperature of 90-110 degrees Centigrade for the bottom section and progressively reducing the temperature of precuring for the intermediate sections up to the top section by a temperature gradient of 4-6 degrees Centigrade. The heater (1 ) comprises a vertically disposed thermal conductor material hollow cylindrical body (2) having a plurality of heater elements (3) of different wattages wound over the cylindrical body one above another corresponding to equal sections of the wound structure from bottom to top of the wound structure.