Apparatus and method for the production o fplastic granulate

Abstract

The invention relates to a method and a device for producing plastic granulate, having a granulator which breaks up essentially continuously conveyed plastic mass flow into granulate particles, the granulator ( 17, 40 ) comprising a cutting unit ( 21, 22; 32, 33, 34 ), whose cutting elements engage on the plastic mass flow when breaking up the plastic, and the device ( 1, 31 ) comprising at least one oscillation sensor ( 24, 25; 60, 61 ), using which oscillations occurring on the device ( 1, 31 ), in particular on the granulator ( 17, 40 ), may be detected.

1 - 27 . (canceled) 
     
     
         28 . A method for operating a device for producing plastic granulate comprising:
 providing a device comprising a granulator which breaks up an essentially continuously conveyed plastic mass flow into granulate particles, the granulator comprising a cutting unit, whose cutting elements engage on the plastic mass flow when breaking up the plastic and at least one oscillation sensor for detecting oscillations occurring on the device,   detecting the oscillations occurring on the device using an oscillation sensor;   measuring and analyzing the oscillation signals in a frequency analysis unit; and   monitoring the production process and/or the status of the device using the data of the frequency analysis unit.   
     
     
         29 . The method according to  claim 28 , wherein the material properties of the material to be granulated selected from the group consisting of temperature, moisture, and/or geometry of the material to be granulated, are monitored using the data of the frequency analysis unit. 
     
     
         30 . The method according to  claim 28 , wherein the setting of the granulator is monitored using the data of the frequency analysis unit. 
     
     
         31 . The method according to  claim 28 , wherein the wear of the granulator is monitored using the data of the frequency analysis unit. 
     
     
         32 . The method according to  claim 31 , wherein preventative maintenance measures are suggested and/or triggered as a function of the analysis result. 
     
     
         33 . The method according to  claim 32 , wherein a remaining run parameter is calculated as a function of the analysis result. 
     
     
         34 . The method according to  claim 33 , wherein the remaining run parameter is compared with the requirement parameters of running and/or upcoming production batches. 
     
     
         35 . The method according to  claim 28 , wherein the actual frequency curve detected by the oscillation sensor is compared with a stored reference frequency curve and/or a stored reference frequency signal in the frequency analysis unit. 
     
     
         36 . The method according to  claim 28 , wherein an actual frequency curve is stored as a new reference frequency curve and/or a new reference frequency signal. 
     
     
         37 . The method according to  claim 36 , wherein the storage of an actual frequency curve as a new reference frequency curve is performed after acknowledgment by the operator. 
     
     
         38 . The method according to  claim 28 , wherein a warning signal is generated if the actual frequency curve approaches a specific reference frequency curve and/or a specific reference frequency signal. 
     
     
         39 . The method according to  claim 38 , wherein the warning signal contains information about the event to be expected and/or information about the duration until the occurrence of this event. 
     
     
         40 . The method according to  claim 28 , wherein an alarm signal is generated and/or an emergency shutoff is triggered if the actual frequency curve deviates beyond a specific reference frequency curve and/or beyond a specific reference frequency signal. 
     
     
         41 . The method according to  claim 28 , wherein the effectively occurring oscillation strength detected using the oscillation sensor is compared with a stored reference oscillation level. 
     
     
         42 . The method according to  claim 28 , wherein an oscillation signal is generated using an oscillation actuator for frequency excitation of the granulator and the oscillations thus caused on the granulator are detected using the oscillation sensor. 
     
     
         43 . The method according to  claim 28 , wherein the frequency curve detected using the frequency sensor is decomposed into individual frequency components of a frequency spectrum in the frequency analysis unit by mathematical frequency analysis methods.