API standard 650 ground supported flat-bottom tanks annular bottom plates

The factors affecting the "small breathing" loss of API standard 650 ground supported flat-bottom tanks are: 1. It is related to the change of temperature difference between day and night. The greater the change of temperature difference between day and night, the greater the loss of "small breathing"; on the contrary, the smaller the change of temperature difference between day and night, the smaller the loss. 2. It is related to the sunshine time of the oil storage tank. The longer the sunshine, the more the "small breathing" loss; otherwise, the less the loss.

Production Weld Tests
Production weld test plates shall be welded for API standard 650 ground supported flat-bottom tanks primary-component butt-welded shell plates when welding procedure qualifications are required to be impact tested per Q.6.2 and Q.6.3. The number of production weld tests shall be based on the requirements of Q.6.6.3 and Q.6.6.4. The locations impact tested (i.e., HAZ and/or weld deposits) shall likewise be the same as required for weld procedure qualifications per Q.6.2 and Q.6.3. Weld testing shall be in accordance with Q.6.6.5. Test plates shall be made from plates produced only from the heats that are used to produce the shell plates for the large welded steel tank.

Above-ground API 650 storage tanks (vertical cylindrical flat-bottomed storage tanks) allow the storage of large volumes of goods at low cost. The only limitation is that they API standard 650 ground supported flat-bottom tanks can be used under atmospheric pressure or relatively small internal pressure. There are different specifications and standards for the design of API 650 storage tanks.