Field-erected aboveground storage tanks are on average 50 feet in diameter and larger, some hundreds of feet wide. They often store chemicals or oil through the production or transportation process. These open area steel environments are a perfect fit for the Legacy One to use as a tool during the internal inspection process.
The American Petroleum Institute (API) 653 sets the standard for internal tank inspections. They give information as to what needs to be inspected, yet offer flexibility for how it can be inspected. For instance, the API 653 requires Tank Roof Evaluations, making it one of the most challenging aspects of entire assessment.
Traditional Methods of Inspection
If any part of the AST needs to be looked at beyond a ladders access, it requires an inspection company to build scaffolding or deploy a rope access team. This can be very dangerous work and even more costly regarding the amount of fees paid and money lost due to longer shutdown times. For example, it can cost over $1 million to scaffold an entire sphere tank without the certainty it even needed to be built in the first place. So how can this be improved upon?