Visual testing (VT) is the most commonly used test method. Because most test methods require that the operator looks at the surface of the part being inspected, visual testing is inherent in most of the other test methods.
As the name implies, visual testing involves the visual observation of the surface of a test object to evaluate the presence of surface discontinuities. Visual testing may be by Direct Viewing, using line-of sight vision, or may be enhanced with the use of optical instruments such as magnifying glasses, mirrors, borescopes, charge-coupled devices (CCDs) and computer-assisted viewing systems (Remote Viewing).
Corrosion, misalignment of parts, physical damage and cracks are just some of the discontinuities that may be detected by visual testing.
