API 650 aboveground petroleum storage tanks weld metal

According to the structure type of floating roof, floating roof API 650 aboveground petroleum storage tanks can be divided into internal floating roof tank and external floating roof storage tank. The internal floating roof tank is a floating roof tank with tank roof. The top is the combination of dome roof and floating roof, the external is dome roof, and the internal is floating roof. There is no vault on the top of the External floating roof tank, only a top plate floating with the storage liquid. The common feature of the inner floating roof tank and the outer floating roof tank is that both of them can reduce the evaporation loss of the storage liquid.

refrigerated tanks secondary components are those whose failure would not result in leakage of the liquid being stored. Secondary components also include those API 650 aboveground petroleum storage tanks components that are not in contact with the refrigerated liquid but are subject to the refrigerated temperature vapors and have a combined tensile and primary bending stress under design conditions that does not exceed 6000 lbf/in.2. Secondary components that could be designed within this reduced stress are roof plates, including roof manways and nozzles with their reinforcement, roof-supporting structural members, and shell stiffeners.

When API 650 storage tank is designed, when the design pressure is small F2 kPa, the impact of air pressure on the API 650 aboveground petroleum storage tanks tank wall thickness is not considered in the tank wall design.