API Std 650 closed top welded storage tanks rod, bar, and structural shapes

Static storage loss is also known as "small breathing" consumption. The rise and fall of the temperature in the API Std 650 closed top welded storage tanks leads to the increase and decrease of the pressure in the tank, which makes the mixed oil gas discharged from the tank, and the external air is sucked into the tank, resulting in the oil consumption. Fluid level loss is also called "big breathing" loss. It is the oil consumption caused by the change of gas space volume in the API Std 650 closed top welded storage tanks during the oil receiving and sending operation, which causes the mixed oil gas to be discharged out of the tank, and the external air is sucked into the tank, resulting in the oil consumption due to the change of liquid level height.

API 620 Tank Standard Post-heat Treatment (Stress Relief)
The post-heat treatment now performed on pressure vessels is of established value, although the mechanism by which the improvement is realized may be open to debate. Post-heat treatment of API Std 650 closed top welded storage tanks tank sections when the plate thickness exceeds 11/4 in. is required as stated in 5.25. In special cases, the possibilities of post-heat treatment after erection should be explored. Post-heating an insulated tank may be possible if an ample source of heat is readily available and if the rigidity of the tank is adequate.
The thermal stress-relief treatment performed on pressure vessels is recognized as a means for reducing the probability of brittle failures.

One of the most widely used design codes is the API 650 Standard, from the American Petroleum Institute. The main objective of this standards API Std 650 closed top welded storage tanks is, through the requirements contained in its various sections, to facilitate the purchase and construction of vertical, aboveground, welded fabricated tanks assuring that required safety regulations are met.