Optional design procedures of API Std 650 mechanically-anchored steel tanks

The cleanliness of the API Std 650 mechanically-anchored steel tanks has a great influence on the safety of the tank and the quality of the oil stored. Keeping the API Std 650 mechanically-anchored steel tanks clean can slow down the corrosion of the tank wall and reduce the pollution to the oil. If the inside of the API Std 650 mechanically-anchored steel tanks is not cleaned all the year round, a lot of rust and metal impurities will be produced in the tank. These impurities will cause the oil to slowly oxidize and deteriorate. The impurities mixed into the oil will also block the filter and oil circuit, causing oil supply failure.

The tank 20-in. inside-diameter nozzle shown in Figure F-6 is located in solid plate in the sidewall of a cylindrical storage tank 148 ft in diameter in an area where the thickness of the wall plate, tw, is 11/2 in. A corrosion allowance of 0.10 in. is required on all surfaces of the tank exposed to the stored liquid. The total internal pressure, Pl + Pg, at the center of the opening is 24.9 lbf/in.2 gauge. The thickness of the API Std 650 mechanically-anchored steel tanks wall plate, t, required by 5.10.3 for the latitudinal unit forces, T2, acting at this level is 1.44 in.

Storage tanks API Std 650 mechanically-anchored steel tanks built to these standards are spread across U.S. refineries, terminals, pipelines, and production facilities. The API 650 petroleum storage tank detailed standard specifies the design, processing, welding, inspection and installation procedures of the storage tank.