API Std 650 carbon and low-alloy steel tanks normative references

Prefabrication requirements for API Std 650 carbon and low-alloy steel tanks, large vertical storage tanks:
1. The machined surface of the edge of the steel plate should be smooth, and there should be no defects such as slag inclusion, delamination, cracks, etc., and the surface hardened layer produced by the flame cutting groove should be removed.
2. Dimension deviation after steel plate processing: the deviation of plate width is less than 1.5 mm, the deviation of plate length is less than 2 mm, and the difference between diagonals is less than 3 mm.

API 620 crude oil tank piping materials made according to ASTM A333 and A350 may be used at API Std 650 carbon and low-alloy steel tanks design metal temperatures no lower than the impact test temperature required by the ASTM specification for the applicable material grade without additional impact tests. For temperatures below those allowed by the ASTM specification, the following paragraph shall apply.

According to API 650 tanks, anchoring devices should be designed to transfer overturning moments to the API Std 650 carbon and low-alloy steel tanks tank foundation. At the same time, according to API 650 tank Appendix F, when the tank is to be anchored, the size of the anchoring parts is determined by the maximum lifting force caused by the internal pressure and wind load or the combination of internal pressure and seismic load.