Hello sir, we have a question regarding tension control with dancer mechanism in surface winding mode, not getting good winding quality in either speed mode or torque even after lots of trial error with different Kp, Ti and Td values. Could you advise what could be the reason for it? Defects are 1. Dancer not stable even after film gets stable tension 2. Corrugating on roll 3. Uneven winding 4. Telescopic roll 5. Too tight winding
Thank you for the question, Hardik. There are many who have drive/tension control problems, such as the one you describe. Programming web drives is a specialty that involves knowing web handling well and knowing web drives well, both are two day courses offered by AIMCAL's Converting School Online. Alternatively, the Web Handling Handbook has 50 page chapters on each of the subjects of tension control, drive control and winding. With efforts such as this plus much field experience, problems such as described above become difficult but 'tractable.' A background less than that make even the simplest questions nearly impossible to answer without asking a hundred questions in return because of this level of complexity is required in web drive systems in order to work well. I have worked on many winders whose drive code was 5,000 PAGES long. In short, we don't 'tune' drives. We 'model' them so closely that the motors might even be able to run without feedback from from load cells and dancers. I suspect that none of that modeling structure is in place and if not, a satisfying fix will not likely come from playing with taper, PID's and so on.
The dancer potentiometer should read about the middle of its output, say 14 mv if the output of the device is 4-20 mv, when the dancer is near the middle of its stroke and near the bottom of its output when the dancer is near the bottom and vice versa for the top. MUCH much more important is DANCER DESIGN, see Web201.16a-c and DRIVE TUNING, see Web201.25a-f or better yet a whole two day course on this by Clarence Klassen.
Great question, but you may not like the answer. This is easy for anyone who has the appropriate technical training including some technicians, some scientists and all degreed engineers. It would take the better part of an hour to teach that to others who do not have that engineering-like training.
In a roofing shingle manufacturing plant is it better to control web tension before the cut to length roll by drum speed or a dancer drum.
Hello sir, we have a question regarding tension control with dancer mechanism in surface winding mode, not getting good winding quality in either speed mode or torque even after lots of trial error with different Kp, Ti and Td values.
Could you advise what could be the reason for it?
Defects are
1. Dancer not stable even after film gets stable tension
2. Corrugating on roll
3. Uneven winding
4. Telescopic roll
5. Too tight winding
Thank you for the question, Hardik. There are many who have drive/tension control problems, such as the one you describe. Programming web drives is a specialty that involves knowing web handling well and knowing web drives well, both are two day courses offered by AIMCAL's Converting School Online. Alternatively, the Web Handling Handbook has 50 page chapters on each of the subjects of tension control, drive control and winding. With efforts such as this plus much field experience, problems such as described above become difficult but 'tractable.' A background less than that make even the simplest questions nearly impossible to answer without asking a hundred questions in return because of this level of complexity is required in web drive systems in order to work well. I have worked on many winders whose drive code was 5,000 PAGES long. In short, we don't 'tune' drives. We 'model' them so closely that the motors might even be able to run without feedback from from load cells and dancers. I suspect that none of that modeling structure is in place and if not, a satisfying fix will not likely come from playing with taper, PID's and so on.
How to calibrate dancer potentiometer
The dancer potentiometer should read about the middle of its output, say 14 mv if the output of the device is 4-20 mv, when the dancer is near the middle of its stroke and near the bottom of its output when the dancer is near the bottom and vice versa for the top. MUCH much more important is DANCER DESIGN, see Web201.16a-c and DRIVE TUNING, see Web201.25a-f or better yet a whole two day course on this by Clarence Klassen.
How to calculate from RPM to MPM. ?
Great question, but you may not like the answer. This is easy for anyone who has the appropriate technical training including some technicians, some scientists and all degreed engineers. It would take the better part of an hour to teach that to others who do not have that engineering-like training.
What is dancer?
It is a pivoting roller with a position sensor that is used to tell a motor how much speed is needed to maintain tension.