During paper web production a system measures and monitors the shrinkage and other characteristics with data to be used by customers to set their processes easily and with reduced wastage

摘要

During the production of a paper web, data regarding the quality and character of the web are transferred to at least one subsequent finishing station to be taken into account and optimize the finishing process. The finishing station can be a printing press or a formatting station where the paper is cut to size. The information on the paper web can give its mechanical and/or technological characteristics, the paper composition, the longitudinal paper profile and at least one lateral profile. When the rolled paper has been cut, the data are attached to the wound roll. At the printing press, the web shrinkage is noted and taken into account for printing, using the shrinkage values and their locations. Mean values are taken for the lateral shrinkage and/or the longitudinal shrinkage along the web. The mean shrinkage value is used to smooth the fan-out. During printing, the expansion of the paper is locked by the shrinkage relating to the paper quality and the shrinkage compensates for the different lateral paper tensions. The paper production machine has a data set at each drum for the shrinkage values with a sorting key for the drum. The lateral shrinkage values are taken into account at given longitudinal intervals. With a given paper width, for printing, a mean shrinkage value is taken into account in the longitudinal and/or lateral direction and/or the lateral shrinkage. The shrinkage curve which is used is described with a straight or a curved segment and a bending or edge offset value. At least one lateral spreading roller is used to compensate for irregular web tensions. Moisture is used to compensate for irregular web expansions, with a higher degree of wetness for paper zones with a low shrinkage value than where there is a high shrinkage. The paper rolls for printing are structured so that one side the width decreases on a linear line with the paper machine towards the center, and the adjacent roll increases its linear line towards the center. The wound paper roll carries a label with the shrinkage data, or the data is provided separately or it can be transmitted through a data network to the printer.