What kind of oil is in the oil immersed transformer?

Transformer oil is a kind of petroleum product. The main components of transformer oil are alkanes, naphthenic saturated hydrocarbons, aromatic unsaturated hydrocarbons and other compounds. Oil immersion

The oil of the transformer plays a role in cooling and insulating.

Transformer oil is a clean and clear liquid, free of sediment, suspended mechanical impurities and cotton-like substances. If it is contaminated and oxidized, and resin and sediment are produced, the quality of the transformer oil will deteriorate, and the color will gradually change to light red until it becomes a dark brown liquid. When the transformer is faulty, the color of the oil will also change. Under normal circumstances, the transformer oil should not be used when it is light brown. In addition, transformer oil can be turbid and milky, oily and dark in color. Transformer oil is turbid and milky, indicating that the oil contains water. The dark oil color indicates the aging of the transformer oil insulation. The oil is black and even burnt, indicating that there is a fault inside the transformer.

Transformer oil is 25# insulating oil, which has relatively stable physical and chemical properties, but has a corrosive effect on rubber and promotes its aging. Because of the high viscosity, it can prevent rust, but cannot remove rust.

Generally, waste oil cannot be added to the transformer. If there are only a small amount of insoluble impurities, or slightly damp, it can be used after filtration, but it must be qualified.

The performance of transformer oil usually has the following requirements:

(1) The density of transformer oil should be as small as possible to facilitate precipitation of moisture and impurities in the oil.

(2) The viscosity should be moderate, too large will affect convection heat dissipation, and too small will reduce the flash point.

(3) The flash point should be as high as possible, and generally should not be lower than 136°C.

(4) The freezing point should be as low as possible.

(5) The lower the content of impurities such as acid, alkali, sulfur, and ash, the better, so as to avoid their corrosion of insulating materials, wires, fuel tanks, etc. as much as possible.

(6) The degree of oxidation should not be too high. The degree of oxidation is usually expressed by acid value, which refers to the amount of potassium hydroxide (mg) required to absorb the free acid in 1 gram of oil.

(7) The stability degree should not be too low. The stability degree is usually expressed by the sediment of the acid value test, which represents the oil's anti-aging ability.