20ft diameter API 650 unanchored tanks

The API 650 unanchored tanks outer wall shall be designed for the purging and operating pressure of the space between the inner and outer tank shells and for the loading from the insulation, the pressure of wind forces, and the roof loading.
The outer tank bottom, shell, and roof shall have a minimum nominal thickness of 3/16 in. (7.65 lbf/ft2) and shall conform to the material requirements of Q.2.3.

These API 650 documents will define the bases of design, operation, inspection, tests, examinations, and maintenance of an API 650 unanchored tanks industrial facility. Bidders will study and analyze all this API 650 documentation, both during the preparation of the quotation and during the execution of each project activity.

Oil tank is often used to store crude oil, diesel oil, gasoline and other oil. The main structure of API 650 unanchored tanks is composed of tank top, tank wall, tank bottom and accessories. The API 650 unanchored tanks should be inspected after the completion of construction, and the detection methods of different structure positions are different. Tank wall inspection: for the newly built oil tank, water filling test shall be conducted to check whether the tank wall is tight, and the appearance inspection shall be conducted for the tank wall plate and weld. Tank wall thickness detection: the oil tank wall thickness is mainly detected by ultrasonic wave, with high efficiency.