Roll Diameter and Web Slack Detection for Printing
Roll Diameter and Web Slack Detection for Printing
Reliable ultrasonic sensing for publication, packaging and label printing, foil lamination and film converting.
ATHENA ultrasonic sensors use non-contact measurement to monitor roll diameter, web slack and tension changes in printing and converting applications.
They work with paper, aluminum foil and plastic film regardless of color, gloss or air permeability, and are suitable for printing presses, laminators, slitters, coaters and bag-making machines.
The sensors provide reliable process data for tension control, diameter calculation, unwind and rewind alignment, and web-break prevention in publishing, packaging, label printing, foil lamination and film converting.
Industries and Applications
- Publication printing: roll diameter and tension control on web presses
- Packaging printing: real-time film and laminated-web tension monitoring
- Label printing: slack detection and automatic alignment
- Aluminum-foil converting: precise diameter and core-position measurement
- Film lamination: diameter matching and balanced tension control
- Slitting and rewinding: real-time diameter calculation and adaptive unwind speed
- Metallizing and coating: web tension monitoring and slack alarms
- Bag making and packaging: remaining-roll monitoring and roll-change warning
Real-Time Roll Diameter on Web Presses
As a web press runs, the unwind roll becomes smaller. Without continuous speed correction, tension changes can cause registration errors or web breaks.
An ATHENA sensor mounted beside or above the roll measures its radius without contact and sends live data to the press controller. The controller adjusts unwind speed to maintain stable tension. Response rates above 50 Hz support high-speed printing, while roll-change signals can trigger automatic slowdown or stop sequences and reduce material loss.
Automatic Unwind and Rewind Alignment
Core deformation and uneven material thickness can make a moving web drift beyond its safe boundary. ATHENA sensors installed on both edges measure deviation from the reference line and send corrections to the guiding controller within milliseconds.
Unlike photoelectric sensors, ultrasonic measurement is unaffected by transparency, color or printed patterns. High accuracy and non-contact operation reduce edge waste, layer misalignment and mechanical wear.
Aluminum Foil Roll Measurement
Accurate diameter control prevents uneven rewind tension, edge burrs and collapsed cores. ATHENA sensors monitor both unwind and rewind diameters with accuracy within ±0.5 mm.
The system predicts roll-change timing, issues early warnings and supports automatic preparation of the next roll. Optimized algorithms maintain reliable measurement on highly reflective aluminum surfaces.
