Calender arrangement

A vertical calender apparatus for treating a paper web, said apparatus comprising:

• a controllable-deflection top guide roll;
• a controllable-deflection bottom guide roll;
• a plurality of auxiliary drives;
• a plurality of guide roll drives:
• a plurality of intermediate guide rolls arranged between the top roll and the bottom roll to define a calender stack, each intermediate roll coupled to one of the auxiliary drives for in-line operation to pull in the paper web during operation;
• a plurality of guide rolls arranged adjacent to the calender stack, each guide roll coupled to one of the guide roll drives;
• a first main power drive to transmit torques to all the rolls frictionally, the first main power drive connected to the top roll via a first gear mechanism;
• a second main power drive connected to the bottom roll via a second gear mechanism, wherein the first and second gear mechanism have the same construction;
• and
• a control unit for driving the first and second power drives at substantially the same power.