The fuel tank is a container on the automobile for storing fuel, and it is a specialized vessel in hydraulic systems for holding hydraulic oil or hydraulic fluid. Tanks can be divided into two types: open tanks and closed tanks. The tank must have a sufficiently large volume; the suction pipe and return pipe should be inserted below the minimum liquid level to prevent air suction and splashing of returning oil, which can cause bubbles; the distance between the suction pipe and the return pipe should be as far apart as possible, with a partition installed between them; to maintain the cleanliness of the oil, the tank should have a sealed cover around the perimeter, equipped with an air filter; the bottom of the tank should be at least 150mm above the ground; sufficient attention must be paid to the anti-corrosion treatment of the inner surface of the tank.