Web201.44f – Bowed Roller Failure Modes – Other
***201.44f – Bowed Roller Failure Modes – Other
05 Slides Duration 02.31 v 15.08.28
201.44f.01 – Title Slide
Welcome to web handling. My name is Dave Roisum. In this final clip in a series we conclude with a few last failure modes for the bowed roller.
201.44f.02 – Other Bowed Roller Concerns
Sometimes it can be difficult to know when to stop. We could go on for hours on bowed rollers. So I will end with a final set of common troubles.
Teaching operators how bowed rollers work and how to operate them is not easy for good reason as we learned in Web101. The bowed roller is one of the most complicated spreaders we have. Still, this complication may be worth it because it is also one of the most capable of spreaders.
In fact, many engineers and even the bowed roller suppliers themselves do not know how bowed rollers work for the simple reason is that many do not read or go to school in all of the details they should know.
As I mentioned in previous clips and detailed in Web101, the bowed roller is not a trivial drive design and tuning application. Then we have many maintenance challenges including cover wear and bearing failure, both of which can degrade spreading even when the cover is not obviously worn or the bearings still turn in some fashion.
Finally, when you get to speeds above a few hundred meters per minute, or certainly the thousands and even 10 thousand feet per minute the paper winder operates at, vibration can be devastating. The bowed roller is a particular challenge here because, unlike most rollers, they can not be balanced. Also, at least 3 resonances are inevitable in the speed range of paper machine winders. Few builders can make a bowed roller good enough for high speed winders and none can do it without fail.
201.44f.03– Thank You
Thank you so very much for watching this module in my plant practical video clip series. Stay tuned for more must-know topics in web-handling.