| 摘要 |
Method of controlling and/or monitoring the coating drying process of a web (W). In the method an endless paper or board web (W) is led through one or more coaters (30), in which coating is applied to one or both sides of the web, after treatment with which the web (W1) is led through one or more dryers (44, 40, 55, 60) for drying the coating. In the last-mentioned dryer, multiple-cylinder drying (60) and/or contactless air-float drying (40, 50, 55) and/or infrared drying (44) is used. A computer (110) is used in the method for the process control. In the method a process model is applied, which is established on the basis of trial runs, on-line measurements and/or the drying theory of the process to be controlled. On the basis of the said process model, the evaporation loadings of the individual dryer units and the dry contents of the paper web to be coated and the temperatures after each of the said dryers are calculated. Grade-related desired value parameters, which correspond to the web grade to be run, are entered into the drying model from a so-called grade and recipe card. At specific time intervals, new output values are entered into the simulation program, as which the measured values (a-k) of the process parameters obtained from the various sensors (1-23) of the coating process and possibly the web.... analysed in the laboratory ... Original abstract incomplete. <IMAGE>
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