API Std 650 self-anchored flat-bottom steel tanks definitions

Except as permitted by API standard 620 Q.8.6, the test shall be conducted after the entire tank is complete, before the insulation is applied. Except as limited by foundation or stress conditions, the test shall consist of filling the tank with water to the design liquid level and applying an overload air pressure of 1.25 times the pressure for which the vapor space is designed. The load on the supporting foundation shall preferably not exceed the established allowable bearing value for the tank site. Where a thorough evaluation of the foundation justifies a temporary increase, the established allowable bearing may be increased for the test condition, but the increase shall be not more than 25%.

Large net shell API 650 tanks or net shell of tank API Std 650 self-anchored flat-bottom steel tanks is a tank top for the surface grid structure and the physical structure form of truss structures, thin shell structure is reasonable, mainly for the top using triangle net shell, socket type net shell or meridian reticulated shell technology for the design of API Std 650 self-anchored flat-bottom steel tanks large-scale tank top, its great spanning capacity and uniform stress, good rigidity, less material, convenient assembly, safe and reliable.

The safety inspection of atmospheric storage tank, API Std 650 self-anchored flat-bottom steel 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 Std 650 self-anchored flat-bottom steel 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.