Lifting and loading device for a roll stack in a calender

摘要

The invention concerns a lifting and loading device 200 to lift and load a roll stand in a calender, especially a supercalender, which comprises a main cylinder 220 in which a first piston 210 is arranged to move axially. The lifting and load device 200 includes an auxiliary cylinder 240 arranged axially within the first piston 210 relative to main cylinder 220, which opens toward the first piston's 210 lower surface 210b and in which an axially moveable second piston 260 is arranged. The lowest roll of the roll stack can be lifted higher and with greater force than with piston 260 of auxiliary cylinder 240 with piston 210 of main cylinder 220. Main cylinder 220 is used during normal operation and auxiliary cylinder 240 is used when the uppermost rolls are in service, in which the operation is conducted only with the lowermost nip. <IMAGE>