PAPER MACHINE OPERATOR REEL/ROLL DISPLAY FOR IMPROVED PAPER QUALITY

摘要

The paper describes a novel display designed to provide the paper machine operator with a real time image of the variations in important sheet properties as the paper is manufactured. Wavelet filtering is used to separate machine direction and cross machine variations as well as to remove high frequency measurement disturbances. The filtered data are displayed as a colour-coded two-dimensional map of the entire roll, together with estimated machine direction variations and cross machine profile. By correlating wavelet data with results from a TAPIO Paper Analyser, it is shown that wavelet filtering allows excellent representation of the true sheet properties without loss of detail, and with highly economical representation of the data. Additional information can be selected that characterizes the roll in terms of mean and standard deviation specifications for the given grade. Any sections of product that do not meet specifications are indicated. An on-line control performance monitoring index informs the operator of the significance of any CD profile variations that lie within the spatial bandwidth of the control actuators. Mean and standard deviations for individual rolls following the slitter are anticipated.