摘要 |
A gloss control system for especially for use on a super calender roll system uses controllable jets of heated air arranged along the segment of a calender roll not in contact with a paper web to both control the overall gloss level and equalize the expansion and contraction of the roll which would otherwise be affected by the heat sink effect of the paper on the contacted portion of the roll causing an hour-glass effect. The air jet units utilize electrical heating elements and are actually arranged along, for example, 1-1/2 inch zones of the paper to provide for a differential profile control with relatively cold air on the uncovered ends of the calender roll to compensate for contraction of the center portion of the roll.
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