3003 aluminum plate API standard 650 ground supported flat-bottom tanks

In this project, a cylindrical tank 62 ft 6 in. in diameter is designed for an internal pressure of 4 lbf/in.2 gauge in the vapor space. The plate material is ASTM A131 steel with appropriate grades for different plate thicknesses in accordance with Table 4-1 for a design metal temperature less than 65°F but not less than 25°F. No corrosion allowance is required for any portion of the tank. The top course of the butt-welded cylindrical sidewall is 1/4 in. thick. The roof is a single lap-welded spherical dome with an internal radius of 50 ft and a thickness of 1/4 in. The maximum design liquid level is 6 in. below the plane of the juncture of the tank API standard 650 ground supported flat-bottom tanks roof and sidewall.

Floating roofs shall comply with API Standard 650, Appendix C (Attachment 01) or with the API standard 650 ground supported flat-bottom tanks requirements as layed (laid )down in the national Chinese specifications SH3046-92 and GBJ128-90.

Natural ventilation loss: the main cause of natural ventilation loss is that the API standard 650 ground supported flat-bottom tanks is not tightly sealed. This is usually due to corrosion perforation on the top of the oil tank, or there is a height difference between the two orifices. The air tightness of the mixture in the API standard 650 ground supported flat-bottom tanks is higher than that of the air, which causes the mixture gas in the tank to be discharged into the atmosphere from the lower hole, and the external air flows into the tank from the high hole, resulting in natural ventilation loss.