Calender and method of operating the same
AssigneeKleinewefers GmbH
InventorsJosef Pav, Gerhard Hartwich, Rolf Van Haag, Franz Kayser
Life of this patent
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Abstract
A calendar wherein a bottom roll and a deformable top roll flank one or more intermediate rolls is operated in such a way that the shape of the top roll is caused to conform to that of the adjacent intermediate roll before the nip of the top roll with the adjacent roll is narrowed. At least the top roll is heated to enhance the satinizing effect upon paper webs without unduly affecting the specific volume of treated material. It is further proposed to subject the bottom roll to preliminary deformation and/or to heat the bottom roll and/or one or more intermediate rolls.
Claims42
A method of operating a calender, particularly a supercalender, wherein a bottom roll and a deformable top roll flank and respectively define first and second nips of variable width with at least one intermediate roll having a predetermined shape adjacent the nip or nips and a material to be calendered is threaded through the nips, comprising the steps of deforming the top roll so that its shape conforms to that of the at least one intermediate roll adjacent the second nip;
- reducing the width of one of the first and second nips;
- and reducing the width of the other of the first and second nips.
A method of operating a calender, particularly a supercalender, wherein a bottom roll and a deformable top roll flank and respectively define first and second nips of variable width with at least one intermediate roll which has a predetermined shape adjacent the second nip and a material to be calendered is threaded through the nips, comprising the steps of heating at least a portion of the top roll to be a predetermined temperature;
- deforming the top roll so that its shape conforms to that of the at least one intermediate roll;
- thereupon reducing the width of the first nip;
- and thereupon reducing the width of the second nip.
A calender, particularly a supercalender, comprising a deformable top roll including a carrier and an elongated deformable cylindrical shell spacedly surrounding said carrier;
- a bottom roll;
- at least one intermediate roll defining with said bottom and top rolls first and second nips of variable width and having a predetermined shape adjacent said second nip;
- means for moving said top roll relative to said bottom roll to thereby vary the width of at least one of said nips;
- and means for deforming said top roll relative to and independently of said at least one intermediate roll, including means for imparting to the top roll a shape conforming to that of said at least one intermediate roll and said imparting means including a plurality of adjustable deforming elements disposed between said carrier and said shell and forming at least one row of primary deforming elements nearer to and at least one row of secondary deforming elements remote from said second nip, said rows extending longitudinally of said shell and said imparting means further comprising means for adjusting said deforming elements.
A method of operating a calender, particularly a supercalender, wherein a bottom roll and a deformable top roll flank and respectively define first and second nips of variable width with at least one intermediate roll and a material to be calendered is threaded through the nips, comprising the steps of calculating the desired temperature of at least a portion of the top roll in accordance with a predetermined algorithm;
- heating said portion of the top roll to a predetermined temperature including selecting the temperature of said portion of the top roll in accordance with the results of said calculating step;
- reducing the width of one of the first and second nips;
- and reducing the width of the other of the first and second nips.
A method of operating a calender, particularly a super calender, wherein a bottom roll and a deformable top roll flank and respectively define first and second nips of variable width with at least one intermediate roll and a material to be calendered in threaded through the nips, comprising the steps of heating at least a portion of the top roll to a predetermined temperature;
- reducing the width of one of the first and second nips;
- reducing the width of the other of the first and second nips;
- and regulating the ratio of load distribution upon the material in the second nip to the influence of heat energy upon the material in the second nip as a function of desired parameters of calendered material.
Dependencies are inferred from the claim text.