| 摘要 |
A cross directional caliper control system for a calender. A coarse caliper control mechanism adjusts the pressure over a first range of values. A fine caliper control mechanism adjusts the pressure over a second range of values, where the second range of values is smaller than the first range of values. Sensors sense the dimension of the paper web passing through the calender. A control mechanism coupled to the coarse calender control mechanism, the fine calender mechanism and the sensors controls the caliper across the width of the paper by varying the nip pressure with both the coarse caliper control mechanism and the fine caliper control mechanism to shift the variability of the caliper so that it corresponds to nip pressure adjustments within the second range of values. Bumpless adjustments of the coarse control mechanism are made by making counteracting adjustments to the fine control mechanism.
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