What is the process for transformer oil filling in power transformers?

The process for transformer oil filling in power transformers involves several key steps. First, the transformer is evacuated to remove moisture and air. Next, transformer oil is heated to reduce viscosity, facilitating easier filling. The oil is then pumped into the transformer through designated filling ports, ensuring that all internal components are adequately submerged. Finally, the filling process is monitored for any air pockets, and the transformer is sealed to maintain oil integrity.