Web201.42e Center-Surface Winder – Why Not?
***201.42e – Center-Surface Winder – Why Not?
05 Slides Duration 03.13 v 15.08.04
201.42e.01 – Title Slide
Welcome to Web-Handling. My name is Dave Roisum. In this clip we will give many reasons why you might NOT want a center-surface winder.
201.42e.02 - Checklist
We introduced this series with reasons why you might want this complicated winder. The checklist here clarifies all of the necessities to make this investment pay back
- Are your defects tightness sensitive?
- Will extending the range of tightness uniquely help you with your particular defects? In other words, you have run out of range with the tension and nip knobs and they can’t be extended further as easily and cheaply as adding a new knob.
- Does the extension of this tightness work at the diameter range of your defects? As we explained in an earlier clip the center-surface winder benefits are largely confined to the core area except with the super-loose gap mode which may suffer from too much looseness are roll diameter builds and more air is entrained.
- Does the cost of the defects that could be recovered with this knob clearly meet payback on capital requirements of your company.
- Do your engineering and maintenance and operating personal all understand what to do with this knob.
We add a few closing thoughts.
- The law of diminishing returns indicates that adding a fourth knob, center-surface winding torque differential, on top of the already existing tension, nip and speed, will be expected to have a relatively small effect.
- Adding a motor on the moving element, whether roll or roller, will inevitably increase the mechanical friction of the nip. This will increase its nip variability and decrease the ability to achieve light nip loads. As we have indicated on many occasions, the nip should be a gold-plated knob and hanging more equipment on to it is not helpful in this regard.
201.42e.04 – What if You Have One You Don’t Need
Just because you have something doesn’t mean you should use it. If the knob does not satisfy all of the requirements we listed earlier, then the knob should not be used. I offer two subcases here.
If the knob is never needed, disconnect the motor.
If the knob is needed for some cases, run that motor at a no load motor torque setting so as to not inadvertently change winding tightness.
201.42e.05 – Questions?
Thank you so very much for watching this module in my plant practical video clips. If you have questions, you may want to replay this clip series. If the material still doesn’t make sense then perhaps my web or winding school might help give you the required background.