A633 Gr C plates API 650 SUG II tanks

The insert plate weld shall not cross any shell seams and shall be at least the greater of 10 times the shell thickness or 12 in. from any other weld in the API 650 SUG II tanks shell including shell seams, shell-to-bottom weld or attachment welds. The butt weld around the periphery of the plate shall be examined over 100% of its length by both liquid penetrant method and radiographic method. The liquid penetrant examination is required on the root pass, on the back-gouged surface, and on the inside and outside finished weld surfaces. Additionally, the weld shall be vacuum box leak tested.

The thickness of the overburden on the top of the API 650 oil tank should not be less than 0.5m. The surrounding backfill with clean sand or fine soil should be no less than 0.3m thick; the API 650 oil tank API 650 SUG II tanks operation platform ladder selection unit is considered in a unified manner. The buried operation well is designed for buried horizontal oil tanks, and the two are compatible.

Static storage loss is also known as "small breathing" consumption. The rise and fall of the temperature in the API 650 SUG II tanks leads to the increase and decrease of the pressure in the tank, which makes the mixed oil gas discharged from the tank, and the external air is sucked into the tank, resulting in the oil consumption. Fluid level loss is also called "big breathing" loss. It is the oil consumption caused by the change of gas space volume in the API 650 SUG II tanks during the oil receiving and sending operation, which causes the mixed oil gas to be discharged out of the tank, and the external air is sucked into the tank, resulting in the oil consumption due to the change of liquid level height.