The Instance of Soft Calender and Hard Nip Calender with Induction Heated Heat-pipe Calender Roll

Presently, the most of paper and paperboard are requesting the good smoothness with a bulk, good gloss, and good printability in the world. In the manufacturing of paper and paperboard, the calendering process is very much important for the quality of them, because it is just finishing process. In the calendering of paper and paperboard, there are many methods of calender as follows. 1) Machine calender of 4 to 6 rolls. 2) Hard Nip calender: 2 rolls between Top roll and Bottom roll. 3) Soft calender. 4) Supercal ender of 12 to 16 rolls. 5) Gloss calender. If install the High temperature heated roll on the calender equipment, it can be made the deduction of the nip pressure, also can be made reduction of numbers of calender rolls. Therefore, recent technology of calender equipment is making the installation of the High temperature heated roll for paper and paperboard. Presently, the many paper and paperboard mills are applying the Soft calender with the High temperature heated calender roll and the Hard Nip calender with the High temperature heated calender roll. The both calender systems with the High temperature heated roll are very much simple constructions, just single nip pressure, and can be made the good quality of paper and paperboard. In these calender equipments, should be installed the Induction heated heat-pipe calender roll, because can be heated up from ambient temperature to max. 3 0 0 1 with an accurate temperature profile on the roll surface under the calendering and high speeds.