METHOD OF IMPROVEMENT OF QUALITY AND RUNNABILITY OF PRODUCTION MACHINE FOR A WEBLIKE PRODUCT
The invention relates to a method for improving the quality of a web-like product and the runnability of a production machine, such as a paper or board machine or a calender. In order to control a nip force fluctuation in operating conditions regarding a pressure load and/or a heat flux and/or a running speed, the rolls are provided with a run-out as desired by machining a desired form on the shell of a roll and/or the shaft and/or bearing components of a roll. The machining is performed in such a way that said desired form is non-circular and/or the centre of rotation of a workpiece has a trajectory as desired.