A surface inspection technique for continuously extruded cylindrical products

The objective of this paper is to provide a brief overview of various inspe ction methodologies for continuously extruded products, such as wire, cable and optical fibres, and to describe the implementation of a practical surf ace inspection technique. The main feature of the developed system is the u se of a conic reflector arrangement to collect light scattered from a cylin drical surface. illumination is supplied by optical fibres, strategically p ositioned around the cone, to provide full circumferential lighting. The in spection arrangement was implemented and tested in an industrial environmen t and effectively detected defects, such as blisters on wire (of diameters 0.2 mm to 3 mm), at a speed of up to 10 m s(-1).