Steel plate for shells of API 650 aboveground petroleum storage tanks

Inspection of low-pressure storage tank Butt-weldsComplete penetration and complete fusion is required (to the degree mandated by the acceptance criteria for examination method utilized) for welds joining tank wall plates to API 650 aboveground petroleum storage tanks tank wall plates. Examination for quality of welds shall be made using either the radiographic method specified in API 620 standard 7.15.1 and applied in 7.17, or alternatively, by agreement between the Purchaser and the Manufacturer, using the ultrasonic method specified in 7.15.3.1. In addition to the radiographic or ultrasonic examination, these welds shall also be visually examined as specified in 7.15.5. Furthermore, the Purchaser’s inspector may visually inspect all butt-welds for cracks, arc strikes, excessive undercuts, surface porosity, incomplete fusion, and other defects.

The working pressure of the low-pressure storage tank is greater than that of the atmospheric storage tank, but its pressure is less than 0.1MPa. API 650 petroleum storage tanks are classified according to their environment: Above-ground storage tank: refers to the bottom of the storage tank at the design elevation of API 650 aboveground petroleum storage tanks and above; the bottom of the tank is below the design elevation of +0.00 but not exceeding.

API 650 aboveground petroleum storage tanks Drain hole: The drain hole is generally installed at the bottom of the oil tank, used to remove sludge when cleaning the oil tank, and usually used to drain the sewage in the tank. API 650 aboveground petroleum storage tanks Safety valve: The role of the safety valve is to play a safety role when the breathing valve fails during the operation of the oil tank. Its working pressure is slightly higher than the pressure of the breathing valve, which can prevent the tank from being damaged due to the high positive or negative pressure in the tank. The safety valve is usually installed in the middle of the API 650 aboveground petroleum storage tanks top.