48m diameter API Std 650 aboveground oil storage tanks

The thickness of the API Std 650 aboveground oil storage tanks annular bottom plates shall be in accordance with Table Q-4 (for steel or aluminum, as applicable). The thicknesses shown are minimums. The ring of annual plates shall have a circular outside circumference, but it may have a regular polygonal shape inside the tank shell with the number of sides equal to the number of annular plates. These pieces shall be butt-welded in accordance with Q.7.1.1, Item b. The plates of the first shell course shall be attached to the annular bottom plates by a weld as required by API 620 oil tank 5.9.5 except when a full-penetration weld is used or required (see Q.7.1.1). Butt-welds in annular plates shall be not closer than 12 in. from any vertical weld.

API 650 tank has the advantages of less load on the floating plate, simple and light structure, and can save the central drainage pipe and rotating floating ladder on the API Std 650 aboveground oil storage tanks floating plate. The materials for easy construction and maintenance and sealing parts can avoid aging due to sunlight.

Welding inspection of bottom plate of API Std 650 aboveground oil storage tanks, vertical oil tank: During the fabrication and installation of API Std 650 aboveground oil storage tanks, the bottom edge plate is welded first. According to the requirements of the technical standard, penetrant inspection is required for the weld of edge plate at the bottom of API Std 650 aboveground oil storage tanks, that is, penetrant testing is required for each weld bead priming, filling and capping. In the process of testing, if any defect is found, it shall be repaired immediately. After the repair, the surface coloring penetrant test shall be conducted again until the test result is qualified.