API standard 650 open top welded storage tanks with a mat foundation

Ultrasonic Examination of Butt-welds in Plates
Butt-welds in all tank wall courses subjected to a maximum actual operating membrane tensile stress, perpendicular to the welded joint, greater than 0.1 times the specified minimum tensile strength of the API standard 650 open top welded storage tanks plate material shall be completely examined.
Butt-welds in API 620 oil tank wall courses subjected to maximum actual operating membrane tensile stress, perpendicular to the welded joint, less than or equal to 0.1 times the specified minimum tensile strength of plate material shall be spot examined in accordance with Figure Q-2.

API 650 vertical tanks meet American Petroleum Industries (API) standards in design, material, fabrication, and testing of aboveground welded steel API standard 650 open top welded storage tanksstorage tanks for use in industrial applications.

During heavy rain, closely observe the change of the water level in the storage area of the API standard 650 open top welded storage tanks. If the water level rises to the dangerous range, drain the water immediately. There are more thunderstorms in heavy rain, and lightning protection devices should be installed in the API standard 650 open top welded storage tanks area to avoid lightning accidents. Observe the groundwater level of the API standard 650 open top welded storage tanks area at any time, clean and dredge the drainage ditch in time to ensure unobstructed drainage, and prevent the bottom of the API standard 650 open top welded storage tanks from leaking and rusting due to untimely drainage.