Operating Experience with the NipcoFloat Supercalender, 1990 Finishing and Converting Conference Proceedings
Conventional supercalenders suffer from inherent operating difficulties which until a short while ago were accepted by mill operators as unavoidable. We resigned ourselves to non-uniform temperature and line force profiles, with heavy rolls i.e. high loading in the bottom nip.
With the development of wider machines, it became obvious that rising demands for product uniformity in the machine and cross-machine directions could never be reached on the conventional basis.
A constant mean line force and resultant uniform line force profile are prevented by continuously changing weights of paper rolls and unstable frictional forces in the loading system. Moreover the intermediate roll guides have unfavourable dimensions for low sliding friction. With their limited guided length and relatively large distance between rolls and vertical guide rails, it is extremely difficult to ensure smooth motion with low friction.
Operating Experience with the NipcoFloat Supercalender, 1990 Finishing and Converting Conference Pro