Why use Non-Intrusive Inspection?

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Using Non-Intrusive Inspection (NII) to complement Risk Based Inspection (RBI) can decrease shut down times, reduce inspection costs and improve integrity outcomes for pressure equipment.

Taking pressure vessels offline, purging and entering them for visual inspection means high costs and potential safety implications for inspectors.

b2ap3_thumbnail_40pc.pngNon-Intrusive Inspection, using emerging non-destructive testing (NDT) techniques, allows some vessels to be inspected in service and produces quantitative data that can be accurately trended. 

With traditional visual inspection, a person enters a vessel and records pass or fail comments on parts of the equipment susceptible to damage. 

The equipment used in NII gives precise, repeatable information on wall thickness and materials flaws, providing that experienced NDT providers are engaged.

Facility operators and maintainers can determine which vessels could be inspected with NII by performing an applicability screening. 

On a recent engagement that involved applicability screening, we found that around 40 percent of the vessels reviewed could be inspected in service using NII techniques. 

For new vessels that are designed with NII in mind, the opportunity to maintain integrity and save on maintenance is greater. 

Data from NII can be used to support and review inspection intervals defined in an RBI plan, a requirement of a continuous risk management process.

Dr. Yury Sokolov, CPEng is a consulting integrity engineer who works with SVT Engineering Consultants.