Proper measurement of thickness is very important for the manufacture of rubber film which is rolled using calendar rollers. Previously random-sample manual measurements were carried out, which is no longer sufficient for today’s demands on quality assurance.
To achieve a better result, eddy current thickness measurement system with three fixed tracks has been adapted for in-line inspection of thickness. For each track an eddy current sensor of Type U6 is built into a jockey follower system which measures against an invar roller.
The invar roller represents the reference system for the measurement. When the jockey follower is located on the roller, the eddy current measurement system reads a thickness of 0mm. When the jockey roller is located on the rubber material, then the eddy current sensor moves away from the calendar roller and the distance of the sensor to the roller corresponds to the thickness of the material.
The eddy current thickness measurement system comprises of:
- 3 U6 eddy – current sensor
- 3 DT11 (single channel electronics)
- 1 Incremental encoder for length measurement
- The application is produced with the graphical development environment ICONNECT
- 3 concurrent signal graphs
- 3 sequential systems with pretensioned ball-bearings (eccentricity 2µm)
- 3 Guide arms, adjustable for track and load pressure
- Invar roll as reference system (diameter 250mm)
The eddy current thickness measurement system is available in Australia and New Zealand from Bestech Australia .