Development and experimental verification of a numerical model for optimizing the cleaning performance of the doctor blade – press roll tribosystem

In the paper production, doctor (scraping) blades are placed in contact with press rolls during wet pressing so as to purge the surface of the rolls from processing water, contamination, and stickies. The contact is achieved by mounting the blade on a holder, which is tilted around a rotation axis until the blade tip contacts with the roll. The contact force is determined by the supply pressure of the air forced through the tube that is placed at the bottom of the holder. Due to contact, the blade wears off and needs to be replaced periodically. Our aim is to optimize the cleaning performance of the system by modelling the tribological contact between doctor blade and press roll, in order to achieve an optimum cleaning performance, thus increasing the blade lifetime and reducing energy consumption. The model is susceptible to an inextensive numerical evaluation. A first comparison with experimental findings is encouraging.