Menetelmä konesuuntaisen ratakosteuden säätämiseksi päällystyskoneella ja kalanterilla

• Main Authors: MAEENPAEAE,TAPIO, IJAES,VESA
• Format: Patent
• Language: Finnish; Swedish
• Published: 14.03.2003
• Edition: 7
• Subjects: ACCESSORIES FOR PAPER-MAKING MACHINES; BLASTING; CALENDERS; DRYING; DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM; HEATING; IMPREGNATING OR COATING OF PAPER; LIGHTING; MECHANICAL ENGINEERING; PAPER NOT OTHERWISE PROVIDED FOR; PAPER-MAKING; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; PRODUCTION OF CELLULOSE; PULP COMPOSITIONS; TEXTILES; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; WEAPONS

The invention relates to a method by means of which the machine-direction moisture of a web being calendered or coated and calendered can be controlled in an optimal manner that takes into account moisture content changes along the entire path of the coating and drying process. Advantageously, all the dryers and the calender of the coater section are controlled in an integrated manner in order to obtain a controlledly processed product which is optimized in regard to energy consumption and product quality. Each process section and unit contributing to the drying of the web is identified by means of a mathematical submodel describing the specific evaporation rate in the respective process section/unit and, by chaining these submodels, a composite model is compiled for the entire process, whereby the composite model makes it possible to manage the drying operation in the process so that the individual units are controlled as a portion of the overall process. In its simplest form, the composite model of the overall process comprises a submodel describing the behavior of the calender and at least one partial submodel describing the web processing unit preceding the calender.