| 摘要 |
Method of controlling cross-direction property profiles of a paper web (5). The method employs a control system (150) for regulating a headbox (3) or headboxes (3a, 3b) of a paper machine. Said property profile or profiles is/are measured by a measurement system (40, 140). The measurement signal thus obtained is supplied to said control system (150). The headbox (3) or headboxes (3a, 3b) is/are supplied with at least two feed streams (11, 12) which contain feedstuffs for the paper suspended in aqueous solution. The feed streams are divided into feed zones in cross-machine sections of the headbox (3) or headboxes (3a, 3b). Said feed zones are each supplied with combinatory streams of said feed streams (11, 12; 11, 12, 13; 11, 12, 13, 14). A property, such as, concentration and/or consistency and/or brightness and/or color and/or equivalent, of one or more feedstuffs of said feed streams (11, 12; 11, 12, 13; 11, 12, 13, 14) is measured. The thus obtained measurement signal is fed to said control system (150). Based on said measurements of the property profile or profiles and based on said measurements of said property and based on setpoint values, control signals are formed. By means of them, an actuator (10) or an actuator combination (10a, 10b) situated at each of said feed zones of the headbox (3) or headboxes (3a, 3b) is regulated, by which actuator or actuator combination combinatory proportions of different feed streams (11, 12) supplied to the feed zone are affected to achieve a desired property profile or profiles of the web (5).
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