The Oil-immersed transformer can be used indoors (outdoors) and can be installed on poles when the capacity is 315kVA and below. The ambient temperature is not higher than 40℃ and not lower than -25℃. The highest daily average temperature of an transformer is 30℃. The highest annual average temperature is 20℃, the relative humidity does not exceed 90% (ambient temperature is 25℃), and the altitude does not exceed 1000m. In daily production and life, how does the Oil-immersed transformer process oil? Let's take a look together next.