Visual Inspection

Visual inspection is the oldest and most common form of NDT used to inspect for corrosion. Surface corrosion, exfoliation, pitting and intergranular corrosion can be detected visually when proper access to the inspection area is obtained. Visual inspection is a quick and economical method of detecting various types of defects before they cause failure. Its reliability depends upon the ability and experience of the inspector. The inspector must know how to search for critical flaws and how to recognize areas where failure could occur.

Visual inspection can be done in many ways either directly or remotely, by using borescopes, fiberscopes or video cameras. Visual methods can provide a simple and speedy way to assess questionable components and can help in deciding what to do next. Where necessary, permanent records can be obtained by photography or digital imaging and storage.

The main drawback of visual inspection is that the surface to be inspected must be relatively clean and accessible to either the naked eye or to an optical aid such as a borescope. Typically, visual inspection lacks the sensitivity of other surface NDT methods. CORROCONT Ltd has corrosion engineers and specialised NDT professionals who perform visual inspection according to the most important international standards like API 653.