Oil storage tank is a container, it is the main equipment of oil library. Material storage tanks can be divided into metal tanks and non-metallic tanks; divided by the location of underground tanks, semi-underground and aboveground tanks tank; installation forms can be divided by vertical, horizontal; divided by shape cylindrical, square box-shaped and spherical. According to the present container made, different materials and specifications, the main material can be made of stainless steel, carbon steel, low alloy steel. Finally, according to customer requirements to design and manufacture and installation. Metal tanks are welded steel plate material into the container. Ordinary sheet metal tanks using a code name A3F boiling open hearth steel; cold regions is used in open-hearth killed steel A3; for more than 10000m3 large volume tank is used in high-strength low-alloy steel. Common metal tank shape, generally vertical cylindrical, horizontal cylindrical, spherical and other types. Vertical cylindrical tanks can be divided according to the top of the structure truss roof tank, no torque roof tank, tank style top beams, vaulted tank, cover pot and floating roof tank top, among the most commonly used is the dome tanks and floating roof tanks. Tank dome structure is relatively simple, commonly used to store raw oil, refined oil products and aromatics. But since the beginning of the floating roof tank floating roof tanks and two kinds of external floating roof tank, the tank has a steel oil floating on the surface of the floating roof, as oil lifting. Floating roof not only reduces oil consumption, and reduce the risk of fire and pollution of the atmosphere. Especially within the floating roof tank, evaporation loss is small, can reduce air oxidation of the oil, to ensure the quality of the oil storage, fire more favorable. Currently internal floating roof tanks at home and abroad are widely used to store volatile light oil, promote the use of a storage tank to be. Horizontal cylindrical tanks applications are very extensive. Because it has to withstand high positive and negative capability, helps to reduce evaporation loss of oil, but also reduces the risk of fire. It can be in the machinery, a batch manufactured and shipped to the site installation, ease of handling and demolition, better mobility. The disadvantage is that the capacity is generally small, the number of multi-use, large area. It is suitable for small-scale distribution depot, rural depots, city gas stations, oil depots or companies affiliated force field depot. In a large depot is also used as a subsidiary tank use, such as cans and put metering cans. Spherical tank with pressure, saving materials, are used for liquefied petroleum gas system, also used as a high pressure solvent tank.