API 650 unanchored liquid-storage tanks double-flanged nozzles

Requirements for prefabrication of the top of large vertical API 650 unanchored liquid-storage tanks: The prefabrication of the tank top shall be prefabricated in blocks according to the drawings. Pay attention to the spacing of the welds after installation when setting out the material. Reinforcing ribs should be formed and inspected with an arc-shaped template. When a single top plate needs to be spliced, butt joints should be used. The forming of a single top plate should be welded between the reinforcing ribs and the top plate on the mould. After forming, check with an arc-shaped sample plate, and the gap should not be greater than 10 mm.

The design metal temperature of API 650 unanchored liquid-storage tanks each component exposed to the liquid or vapor being stored shall be the lower of the following:
a)The minimum temperature to which the tank contents will be refrigerated, including the effect of subcooling at reduced pressure.
b)The minimum metal temperature anticipated when the atmospheric temperature is below the refrigerated temperature (see 4.2.1). The effectiveness of the insulation in keeping the metal temperature above the expected minimum atmospheric temperature shall be considered.

API was established in 1919. It is the first national-level business association in the United States. It is one of the earliest and most successful chambers of commerce in the world to formulate standards. An important task of API API 650 unanchored liquid-storage tanks is to be responsible for API 650 oil storage tanks and natural gas. Standardization of industrial equipment to ensure the safety, reliability and interchangeability of equipment used in the industry.