Non-Destructive Testing Methods: VISUAL INSPECTION

Visual Inspection (VT) is the oldest and most basic method of inspection. It is the process of looking over a piece of equipment using the naked eye to look for flaws. It requires no equipment except the naked eye of a trained inspector.

VT is one of the most commonly used types of Non-Destructive Examination for the detection of discontinuities before they cause major problems like welding defects, base material defects, corrosion, erosion, general condition, etc. What is seen by the naked eye is compared with physical requirements to determine compliance with specifications.

A great example of VT in our world is a dimensional check, where the physical location of features on a unit is checked against the engineering drawings and specifications.

As are most NDE types, the American Institute of Nondestructive Testing provides guidelines and training required to become a Level I or Level II VT Technician. If Code requires VT, then the person administering the VT must be properly credentialed. VT can be via direct (by eye) or indirect (remote). Considerations during course study for VT are the mechanics of the eye, illumination requirements, surface conditions, test specimen attributes, and various other topics.

There are many “fancier” and more tech-forward types of NDE (which we will discuss in future segments), however, most everything can benefit from a proper VT.