API 653 TANK VISUAL INSPECTIONS

In-service tank visual inspections are performed to access on-going reliability and to comply with governing standards. Visual inspections are often completed along with magnetic flux exclusions (MFE), remote ultrasonic testing, vacuum box testing, settlement surveys, and/or tank strapping, to provide a complete picture of the tank condition. Tanks are also visually examined for quality assurance during fabrication and refurbishing. An API-653 certified inspector performs these inspections.

Inspections are performed on tanks that are visually accessible in petrochemical plants, refineries, power plants, farm, pulp and paper mills, etc. Tanks are inspected at regular intervals to assess their fitness for service and to monitor their settlement. Typically, floors, shells, roofs, floating roofs, nozzles and appurtenances are examined.

Adequate cleaning of the tank interior is required to perform an internal inspection. Total, or partial, removal of insulation and cladding is often required prior to external inspections. Knowledge of the equipment history is essential for an in-service inspection. Safety factors, such as confined space entry and/or the presence of H2S, may limit inspection capabilities or timing on in-service inspections.

Visual inspections of tanks are performed per API-653 guidelines and per customer specifications. For new tank inspections progress reports are issued as the project proceedes. The progress reports are followed by a complete job package. Standard reports are comprehensive computer generated documents. They contain the results from both the API 653 inspection and any other examinations performed.