Visual testing (VT), also known as “remote visual inspection” (RVI) means the visual inspection of objects, components or parts of components. Visual testing is one of the surface testing methods in non-destructive testing (NDT).
A VT inspection can be carried out after final manufacture, as an inspection during production (e.g. after welding, machining, etc.) or as recurring inspection (e.g. visual inspection of pipelines in power plants). Quality features such as surface condition, cleanliness, dimensional accuracy and other characteristics are tested and also checked for deviations from underlying specifications such as standards.
As a rule, a distinction is made between the general visual inspection (overview inspection) and the special visual inspection. In the overview inspection, the general condition and external cleanliness are checked. The special visual inspection involves more intensive inspections, such as a detailed inspection of a weld seam for irregularities.