Web materials—such as paper, plastic films, metal strips, or textiles—are often joined with adhesive tape, either butted or overlapping. A ultrasonic splice sensor detects these splices or adhesive bonds in the web material, which is typically unwound from a coil, non-contact and reliably.
How Splice Detection Works?
An ultrasonic transmitter emits a rapid sequence of pulses from below onto the web material. These sound impulses cause the material to vibrate, resulting in a significantly attenuated sound wave being emitted on the opposite side. The receiver captures this sonic wave and analyses it. The web material signal level is different to that of the splice or adhesive bond. And this difference in signal is analysed by the splice sensor.
However, the difference in signal levels between the web material and a splice can be very small. To ensure reliable detection, the ultrasonic sensor must first learn the signal level of the web material.
Typical Applications of Splice Sensors
- Detecting adhesive bonds in paper webs
- Identifying splices in films or plastic webs
- Monitoring splices in metal strips (coil monitoring)
- Detecting weld seams in pouch packaging
