API Std 650 self-anchored tanks seal membrane

Butt-welded joints used to fabricate large steel storage tank fittings shall be completely radiographed. Lines carrying liquid shall be hydrostatically or pneumatically pressurized at a minimum pressure of 35 lbf/in.2 and API Std 650 self-anchored tanks butt welded joints shall be simultaneously visually examined (hydrostatic) or solution film tested (pneumatic) for tightness. If manufactured pipe has been hydrostatically tested previously to ASTM requirements, then only circumferential welds need to be examined.

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 Std 650 self-anchored 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.

Welding inspection of bottom plate of API Std 650 self-anchored tanks, vertical oil tank: During the fabrication and installation of API Std 650 self-anchored 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 self-anchored 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.