METHOD AND APPARATUS FOR CONTROLLING MOISTURE OF PRODUCT DURING PAPER CHANGING TIME IN PAPER MACHINE

摘要

A paper changing operation control apparatus provided in a paper machine, which has web drying simulation function for drier parts, so as to improve the reliability of a paper changing control operation in a paper machine and reduce the paper changing time. When the water content of a web WE is changed to a predetermined target level during the paper changing time in a paper making operation in which the web WE is wound around a steam drum (14a) with canvas (14b) and dried, a thermal equilibrium equation is introduced between the steam drum (14a), canvas (14b) and web WE with a temperature difference around the circumference of the steam drum (14a) assumed to be zero, and a feed rate of steam supplied to the steam drum (14a) is regulated on the basis of this thermal equilibrium equation, whereby an operation for setting the water content of the web WE to a predetermined target level is controlled.