ASTM A27 grade 415-205 floating roofs API Std 650 carbon and low-alloy steel tanks

The main types of metal storage tanks are vertical dome roof tank, vertical external floating roof tank, vertical inner floating roof tank, spherical oil tank and horizontal oil storage tank. API Std 650 carbon and low-alloy steel tanks is vertical tank. The capacity of vertical dome roof oil storage tank is generally less than 10000 cubic meters. The wall plate adopts sleeve type fillet weld, and it is usually installed by inverted or forward installation method during construction.

The opening pressure or vacuum of the pressure relief and API Std 650 carbon and low-alloy steel tanks vacuum relief valves shall be checked by pumping air above the water level and releasing the pressure and then partially withdrawing water from the tank. After the tank has been emptied of water and is at atmospheric pressure, the anchorage, if provided, shall be rechecked for tightness against the hold-down brackets. Air pressure, equal to the design pressure, shall be applied to the empty tank, and the anchorage, if provided, and the foundation shall be checked for uplift.

Before pressure test, the main drain hose system of API 650 petroleum storage tank floating roof should be thoroughly flushed. Provide blind flanges, gaskets and bolts required for the API Std 650 carbon and low-alloy steel tanks test (other types of covers are also required if necessary). Covers for maintenance shall be provided in accordance with the interfaces specified by API 650 petroleum storage tanks, and these seals shall remain in place after the test; and for those interfaces that are not provided for maintenance covers, the covers can be removed after the API Std 650 carbon and low-alloy steel tanks test.