This begins the first in a series of user submitted defect descriptions. Send me your pic and problem description and I will do my best to figure it out or tell you where to go (for more help). I promise to sanitize the description so thoroughly to protect the guilty.
We have many crepe wrinkles as well as defects such as shown in the picture above. The material is slippery uncreped tissue. We are winding this on an old two-drum winder that had been used for linerboard that has a rider roller with an 8 PLI minimum load. Could these defects be associated with baggy webs/lanes? - Anonymous
Possibly, bagginess already causes enough troubles on just about any material, especially when wound with a nip. However, lets start with what we can know for sure and then proceed to best guesses. This defect is certainly a web quality defect in that the locations of the defects are places where the web is different than its neighbors or the mean/average. In other words, the web rather than the winder mostly owns the locations of the defect. That is not to say the winder does not also have a role to play. It is most certainly also a winding defect because these defects show up after winding.
You say you also have many crepe wrinkles. I am also going to guess that the pictured defects are in fact just another way of a crepe-like behavior to develop, call it an incipient or baby crepe if you want. Certainly the picture resembles a partial core burst such as seen just above the unwinds on printing presses supporting large roll weights (if you cut the defect down its centerline to make an 'edge' much like a core has an 'edge’). The picture also resembles even more closely a 'caliper shear burst', a rare and debated separately listed defect in Roll and Web Defect Terminology. What connects all of these supposedly different defects together is mechanism, interlayer slippage under a heavy rotating nip.


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