API 650 ground supported flat-bottom tanks designed for seismic forces

Structural shapes of 9% and 5% nickel steel may be furnished to the chemical and physical requirements of ASTM A353, A553, or A645. Physical tests shall be in accordance with the requirements of ASTM A6.
API 650 ground supported flat-bottom tanks used Piping, Tubing, and Forgings
Material used for piping, tubing, and forgings shall be compatible in welding strength, and thermal expansion coefficient with the tank shell material. In addition to the specific requirements of this appendix, all piping within the limitations of 1.3.2 shall fulfill the minimum requirements of ASME B31.3.

Welded steel API 650 ground supported flat-bottom tanks storage tanks that are designed, manufactured and installed on the ground are classified according to the API standard system. The three API standards API 650 ground supported flat-bottom tanks all adopt on-site production and installation of storage tanks.

The safety inspection of atmospheric storage tank, API 650 ground supported flat-bottom tanks is divided into external inspection, internal and external inspection and comprehensive inspection. External inspection shall be conducted at least once a year, internal and external inspection shall be conducted at least once every three years, and comprehensive inspection shall be conducted at least once every six years. The safety inspection of large atmospheric storage tanks, API 650 ground supported flat-bottom tanks requires special attention: the parts where the liquid level often fluctuates, the parts that are susceptible to corrosion, and the parts that are deformed and worn during use should be checked.