Application:
 In-line sheeter (cutter) of a corrugated sheet manufacturing
plant.
Corrugated paper is fed to the sheeter (cutter) section by felt section cum scoring / pull unit. Line speed of the machine is 50 metres per minute.
Earlier arrangement:
Originally, an eddy current drive was driving the pulling section of the machine. A PIV was used for adjustments of sheet length. Input of the PIV was driven from the main (eddy current) drive with the output of PIV connected to a rotary cutter through
mechanical transmissions.
Requirements:
Dynaspede was commissioned to retrofit new drives and a control system to enhance machine performance, accuracy and consistency of cut lengths from 700 mm (min) to 2500 mm (max). With the earlier arrangement, cut lengths were found to vary as much as 15 mm from desired lengths.
Modifications:
 The PIV was replaced by a 7 kW AC Servomotor with a built-in pulse resolver and suitable torsional couplings. An independent pulse resolver (attached to a spring loaded measuring wheel in direct contact with the moving web) kept track of the line speed and fed this information to an advanced digital control system. Specially developed engineering software provided a perfect electronic gearing to the rotary cutter and controlled its position and velocity profile for precise speed matching during the cutting operation.
The Man-Machine interface through user friendly keypads for settings of Cut Lengths was also provided in the form of a machine mounted operator station.
Benefits:
Production increased substantially. Savings on time and material resulted in a sharp increase in plant productivity, to the extent that the client claimed - the system would pay back in less than six months’ period. All this is possible due to factors described below:
- Accurate cutting – The accuracy of cut lengths was found to be within 1mm of the desired length.
- Consistent lengths – Long-term consistency of cut lengths was found to be within the specified tolerance of 1mm, thus eliminating rejects and wasteful activities of inspection/sorting.
- Now the setting made easy –
- The cutter gets it right the first time
- Operator keys in the desired length and revs up the machine to full speed without any waste even during speed changes
- No skilled operator needed for repeated trial and error methods of length settings
- A digital read-out shows the length of cut, obviating the need for manual length measurements before or after the cut
Our offerings for Corrugation lines: |
