Visual inspection is the one of the oldest method used extensively to evaluate the condition or the quality of a roll surface. It is easily carried out, inexpensive and usually doesn't require special equipment. It is used most effectively for the inspection of roll surface where quick detection of defects can result in significant cost savings. It is the primary evaluation methcd of many quality control programmes.

It requires good vision, good lighting and the knowledge of what to look for. Visual inspection can be enhanced by various methods ranging from low power magnifying glasses through to boroscopes. These devices can also be used with television camera systems. Surface preparation can range from wiping with a cloth to blast cleaning and treating with chemicals to show the surface details.

Visual inspection is often enhanced by other surface methods of inspection which can identify defects that are not easily seen by the eye.

Cracks on the roll surface (Roll diameter: 200 mm).

Spalling of roll surface (Roll diamter: 210 mm).