Pin-point detection of glue traces

Leuze: The system VSU12 comprising two ultrasound sensors and a separate indicating unit was developed specifically for the reliable detection of glued joints in paper webs. This system is able to recognize glue joints independently of the roller and glue material, the adhesive tape colour and the execution of the glue joint.

As the ultrasound sensors are able to recognize the glued joints either within a roller or between a main and a secondary roller not only almost irrespective of the material, colour and properties of the gluing material, but also independently of the roller material, the same glue joint sensor can be used to process not only paper but also film material. And furthermore, the system adapts automatically after a change of material without even requiring a teach-in process for the new material. All the operator does is to preselect the basic material at the indicator unit once. The indicator unit then adjusts automatically to the noise permeability of the roll material. The maximum web speed at which this system goes on being able to reliably detect glue joints depends on the width of the adhesive tape used. With an adhesive tape width of, for example, 30 mm, the maximum speed is 18 m/s.