Atmospheric Storage Tank 

AST – An Atmospheric Storage Tank is a common piece of equipment found on petrochemical plants. These tanks store contents at atmospheric pressure and can be made from both metallic and non-metallic materials. They are also referred to as above-ground storage tanks.

A common type of AST has a floor, a cylindrical shell and a roof and is constructed from carbon steel. Leaks from ASTs can have serious consequences, especially leaks from the floor that may go undetected for a period of time. As a result, ASTs are required to undergo a regular inspection regime. The requirements for inspecting the floor and annular plates, the shell plates and the roof for corrosion, deformation and cracking in welds call on a variety of NDT techniques, including acoustic emission, magnetic flux leakage (MFL), pulsed eddy current and a mixture of ultrasonic 

For more information on NDT of ASTs, see:

For more information on MFL inspection of AST floors, see:

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