Calender

A process of quick releasing nips in a calender that includes a stand, an upper roll, a lower roll, at least two center rolls arranged between the upper and said lower rolls, at least two cylinders arranged to support the at least two center rolls on the stand, where each of the cylinders include a discharge path, said process comprising:

• lowering the lower roll away, whereby closed nips between adjacent rolls are opened,
• during opening of the nips, controlling a discharge path of the cylinders supporting the at least two center rolls over more than ¾ of a piston stroke for lowering the at least two center rolls.

A calender comprising:

• a roll stack comprising a plurality of rolls, said plurality of rolls including an upper roll, a lower roll, and at least two center rolls located between said upper roll and said lower roll;
• compensation cylinders, each compensation cylinder comprising a piston and a cylinder housing, wherein at least one compensation cylinder is associated with each at least two center rolls;
• each said compensation cylinder further comprising a pipe slidably extendable into said piston, said pipe comprising a wall and a plurality of through holes arranged over a length of said pipe.