API standard 650 self-anchored flat-bottom tanks single-welded butt joint with backing

The specifications used in the design of large oil tanks, API standard 650 self-anchored flat-bottom tanks mainly include American Petroleum Institute Standard API 650, Japanese Industrial Standard JIS B8501, British Industrial Standard BS2654 and Chinese National Standard GB50341 from a global perspective. The formulas used in each specification are based on the hoop stress in the membrane theory. Each specification is based on the performance characteristics of materials and the construction technology level of their respective countries to determine the allowable stresses and weld coefficients. Therefore, the calculation results of tank wall thickness of API standard 650 self-anchored flat-bottom tanks with the same volume are sometimes quite different according to different specifications.

Large Steel storage tank Anchorage
In addition to the loads in API 620 oil storage tank Q.4, Q.5.1, and Q.5.2, the anchorage for the tank that contains liquid, whether it be a single-wall tank or the inner tank of a double-wall tank, shall be designed to meet the requirements of Q.3.6.2 through Q.3.6.5. The anchorage shall accommodate movement of the tank wall and bottom caused by thermal changes. For anchored flat-bottom tanks, the anchorage shall be designed as described in Q.3.6.4.1 through Q.3.6.4.3.

Lateral braces between outer bay rafters must be provided if asymmetrical structural shapes are used for rafters and if the API standard 650 self-anchored flat-bottom tanks API 650 tanks are located in areas subject to earthquakes. The bracing must be adequately sized for the seismic zone specified.