Bushings provide insulated paths for high-voltage conductors to pass from the transformer windings inside the tank to external connections. In HV applications, they must withstand high electric fields, mechanical loads, and environmental exposure. Capacitive-graded or condenser bushings control the electric field distribution to prevent partial discharge and surface tracking. Their performance directly affects reliability; many transformer failures originate in aged or contaminated bushings, so testing and maintenance are critical in high-voltage substations.