Vertical cylindrical oil tank refers to the "oil storage tank" with vertical cylindrical tank body. The design capacity of the tank is from 100m3 to 150000m3, which can generally bear 2KPa positive pressure and 0.5kpa negative pressure. It is composed of bottom plate, arc wall plate, top plate and oil tank accessories, which are often installed and welded on site. According to the tank roof structure, it can be divided into cone roof, arch roof, weak moment roof and floating roof oil tank, among which arch roof and floating roof tank are the most widely used. The outer surface of the tank bottom plate is in contact with the foundation, and the inner surface is often in contact with the water and sludge precipitated from the oil, which is vulnerable to corrosion. The side plate at the edge of the bottom plate is connected with the wall plate, and the stress is complex. Thick steel plates are often used. According to the volume of the oil storage tank, the thickness of the bottom plate is usually 4 ~ 8mm, while the thickness of the side plate is 4 ~ 12mm.

The tank wall plate is divided into several circles. The vertical joint of each circle of wall plate adopts butt welding. The connection between adjacent ring plates of dome roof tank is usually lap welding, while the floating roof tank adopts butt welding. Lap welding is simple and easy to ensure installation quality; Butt welding makes the tank have the same diameter, which is convenient for the floating roof to move up and down with the liquid level. The tank wall bears the circumferential tensile stress generated by hydrostatic pressure. With the increase of the height from the bottom plate, the liquid pressure and the circumferential stress on the tank wall decrease, and the thickness of the wall plate can be reduced accordingly. According to the tank capacity, the thickness of the wall plate changes in the range of 4 ~ 40mm. See "dome roof tank" and "floating roof tank" for the top structure.