摘要 |
Web flutter is suppressed by means of one or more foils along the path of movement of the web which may be porous, such as tissue, whether creped or not, or may be substantially non-porous. For porous web, the foil may be imperforate. For non-porous web, the foil may be foraminous. As the web travels at high speed in adjacently spaced relation to the foil, surface air pressure tends to be greater on the surface of the web opposite the web surface which faces the foil, thus tending to thrust the travelling web toward the foil, and thus stabilizing web travel and suppressing tendency for the web to flutter as it travels freely between supports such as a dryer and a calender.
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