MEASURING PHYSICAL-PROPERTIES OF PAPER WITH AN ONLINE VISUAL SENSOR

Experimental results of a novel on-line paper shrinkage sensor are pre sented, showing a clear correlation with laboratory test indices such as elongation, breaking load and tensile energy absorption. Trials car ried out in a paper machine producing sack paper also include a dynami c analysis of the effect of jet-to-wire ratio on paper shrinkage based on these measurements. The measurement is based on digital image proc essing techniques and provides a tool for instantaneous corrective con trol of physical variables during paper manufacture.