Kapa (I & II)

KAPA is the successful model of SBI, developed for films. Kapa I up to 2mm thick. Kapa II up to 6mm thick.

This indirect measuring system with a measuring roller has an extremely robust sensor combination in one housing: capacitive and eddy current sensor.


measuring principle

It uses a non-contact, indirect measuring method. If we measure the capacitance between sensor and measuring roller, this is corrected by the distance measurement of the eddy current sensor. From this, the thickness is calculated in comparison with a calibrated value.


When the extrusion system is running, the sensor is set to a fixed position (measurement along a line). At the sensor position, a piece of the film is cut out, and the thickness is measured. This thickness is then entered as the calibration value. Calibration is only necessary once per material (recipe) and can be saved with the recipe.

Technical Specifications Kapa Kapa II
sensor system capacitive/eddy current capacitive/eddy current
Max. thickness 2 mm 6 mm
measured cleaving 4,5 mm 9,5 mm
sensor diameter 30 mm 45 mm
measuring spot diameter 12 mm 18 mm
sensor resolution 0,05 µm 0,05 µm
accuracy ≤ 0,1 μm ≤ 1,0 μm
measuring speed 10 – 300 mm/s adjustable 10 – 300 mm/s adjustable
process speed 10 – 500 mm/s adjustable 10 – 500 mm/s adjustable
calibration necessary necessary
diameter of the refernce roller 200 mm 200 mm