Method and system for maintaining runnability in a paper or board machine

Abstract

A method and system for maintaining runnability in a paper or board machine, which machine for making paper or board includes two or more successive section complexes, such as a web formation section, a press section, a drying section and a finishing device, and wherein at the section complex (i) cleaning measures are carried out, (ii) the cleanness level is checked, (iii) if the cleanness level does not meet the criteria established for it, the procedure continues from step (i), otherwise, (iv) the cleanness level is accepted. Checking of the cleanness level is performed by using computer vision and the observations obtained by computer vision are compared with a criterion value established to correspond with the required cleanness level, and based on this value the procedure either continues with cleaning measures (i) or the cleanness level is accepted (iv).

1 - 15 . (canceled)  
   
   
       16 . Method for maintaining runnability in a paper or board machine, which machine for making paper or board includes two or more successive section complexes, such as a web formation section, a press section, a drying section and a finishing device, and where at the section complex before tail threading steps (v-vi) 
 (i) cleaning measures are carried out,    (ii) the cleanness level is checked,    (iii) if the cleanness level does not meet the criteria established for it, the procedure continues from step (i), otherwise,    (iv) the cleanness level is accepted,    (v) the threading tail is led in one or more steps, and    (vi) the threading tail is spread out to form a web in its full width,    and in which at the section complex before the tail threading steps (v-vi) or when starting the tail threading the machine running conditions are established for threading of the tail, characterized in that checking of the cleanness level is performed by using computer vision and wherein the observations obtained by computer vision are compared with a criterion value set up to correspond with the required cleanness level, and based on this value the procedure either continues with cleaning measures (i) or the cleanness level is accepted (iv).    
   
   
       17 . Method according to  claim 16 , characterized in that as the said machine running conditions are established, for example, 
 a speed difference, for example, between different section complexes,    temperature conditions, for example, temperature of cylinders in the drying section,    a moisture level of the threading tail and/or the web.    
   
   
       18 . Method according to  claim 16 , characterized in that the section complex includes one or more fixed and/or movable detection means, such as, for example, cameras.  
   
   
       19 . Method according to  claim 16 , characterized in that the section complex includes fixed and/or movable cleaning means for carrying out the cleaning measures.  
   
   
       20 . Method according to  claim 16 , characterized in that the carrying out of cleaning measures and/or the cleanness level check and/or the step where tail threading is started (i, ii and/or iv) is carried out by using a remote control functionality.  
   
   
       21 . Method according to  claim 17 , characterized in that measuring based on definition of the web tension is used in the break detection.  
   
   
       22 . Method according to  claim 17 , characterized in that optical detectors are used in the break detection.  
   
   
       23 . Method according to  claim 16 , characterized in that targeting information of the detection means is used in the targeting of cleaning means to the target to be cleaned.  
   
   
       24 . Method according to  claim 16 , characterized in that at each section complex the measures (i-v) preceding the threading (vi) of the tail are carried out almost simultaneously.  
   
   
       25 . Method according to  claim 16 , characterized in that the machine's control system is arranged to be a learning system, which stores information on the cleaning and/or tail threading events and utilises the information in corresponding new cases.  
   
   
       26 . Method according to  claim 16 , characterized in that the section complex is illuminated with ultraviolet light during the cleanness level check (ii).  
   
   
       27 . Method according to  claim 16 , characterized in that information is formed of the observations in the cleaning steps (i-iv) and/or tail threading steps (v-vii) to carry out condition monitoring, which information is relayed to a special remote monitoring functionality for analysis.  
   
   
       28 . System for maintaining runnability in a paper or board machine, which machine for making paper or board includes two or more successive section complexes, such as a web formation section, a press section, a drying section and a finishing device, and wherein at each section complex means are fitted for maintaining runnability in the connection with the tail threading, characterized in that the said means include one or more detection means covering mainly the section complexes, which means are arranged to monitor the cleanness level of the section complex for threading of the tail, and the observations made by the detection means are arranged to be compared with a criterion value, which is set to correspond with the required cleanness level for threading of the tail and based on which the cleanness level is arranged to be either rejected or accepted.  
   
   
       29 . System according to  claim 28 , characterized in that the means also include cleaning means.  
   
   
       30 . System according to  claim 28 , characterized in that the detection means are arranged to control the cleaning means.