Certain industries baffle me because they break all the rules of web handling by going slack web between sections. Textiles do this when pulling out of a fan folded box or from a J-table. Both textiles and the (paper) forms industry use slack webs between the unwind and the printer or other converting machine.
Silly people. Web tension in the unwinding roll is lost as it is unwound and then re-established on the next roller. Position which was established on the unwinding roll is lost as it is unwound and re-established on the next roller. Worse yet, the machine carries redundant parts because an extra motor and often extra guide are required which increases equipment costs. Worse yet, the machines have poorer performance by re-establishing what was already there (tension and edge position).
Go figure. Yet if it was good enough for grandpa, it was good enough for their new machines despite the fact that almost all other industries hold tension and position at the unwind and can do it under much more challenging situations such as on materials as weak as tissue, at widths from string-like to 40 feet wide and at speeds from crawl to exceeding 10,000 feet per minute.
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