How is oil filtration of a transformer performed?

Oil filtration of a transformer is performed using a vacuum filtration system or a centrifugal separator. The process involves circulating the transformer oil through a filtration unit that removes moisture, particulate contaminants, and dissolved gases. The oil is heated to reduce viscosity, enhancing the filtration efficiency. After filtration, the oil is tested for dielectric strength and other properties to ensure it meets operational standards before being reintroduced into the transformer.