140ft diameter API 650 insulated tanks

Weld inspection of API 650 insulated tanks, vertical oil tank wall plate: In the welding inspection process of oil tank wall plate, attention should be paid to the defects of thick wall plate, such as incomplete penetration, incomplete root fusion and cracks. If there is a root incomplete penetration defect, it is necessary to open the weld joint with carbon arc air gouging and grinding machine grinding, or even weld through, and then weld again after the defect is removed.

The API 650 insulated tanks outer tank, which is not in contact with the vaporized liquefied gas, may be of single-welded lap or single-welded butt construction when the thickness does not exceed 3/8 in.; at any thickness, the API 620 oil tank outer tank may be of double- welded butt construction without necessarily having full fusion and penetration. Single-welded joints shall be welded from the outside to prevent corrosion and the entrance of moisture.

The inner layer of API 650 tank is the same as that of single layer tank. It is made of high-quality steel plate in strict accordance with the standard of "steel welded atmospheric pressure vessel". The thickness of API 650 insulated tanks steel plate reaches the standard and the service life is longer.