Patent
Calender and method of operating the same
| العنوان: | Calender and method of operating the same |
|---|---|
| Patent Number: | 5,029,521 |
| تاريخ النشر: | July 09, 1991 |
| Appl. No: | 07/259,331 |
| Application Filed: | October 18, 1988 |
| مستخلص: | 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. |
| Inventors: | Pav, Josef (Krefeld, DEX); Hartwich, Gerhard (Krefeld, DEX); Van Haag, Rolf (Kerken, DEX); Kayser, Franz (Geldern, DEX) |
| Assignees: | Kleinewefers GmbH (Krefeld, DEX) |
| Claim: | We claim |
| Claim: | 1. 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. |
| Claim: | 2. The method of claim 1, wherein said deforming step precedes the step of reducing the width of the second nip and the step of reducing the width of the first nip precedes the step of reducing the width of the second nip. |
| Claim: | 3. The method of claim 2, further comprising the step of applying a load to at least one of the bottom and top rolls in a direction to urge the at least one of the top and bottom rolls toward the at least one intermediate roll upon completion of the width reducing steps. |
| Claim: | 4. The method of claim 3, wherein said load applying step includes applying to the at least one of the top and bottom rolls a force other than gravity. |
| Claim: | 5. The method of claim 3, wherein said load applying step includes establishing uniform load distribution in that nip which is adjacent the nip of the at least one of the bottom and top rolls with the at least one intermediate roll. |
| Claim: | 6. The method of claim 5, further comprising the steps of monitoring at least one parameter of calendered material, comparing the monitored parameter with a reference value, and applying to at least one of the bottom and top rolls at least one additional load when the monitored parameter deviates from the reference value so as to eliminate or reduce the deviation. |
| Claim: | 7. The method of claim 2 of operating a calender wherein the bottom roll is deformable, further comprising the step of deforming the bottom roll not later than during reduction of the width of the first nip so as to establish uniform load distribution in the first nip. |
| Claim: | 8. The method of claim 7, wherein said step of deforming the bottom roll includes accounting for the influence of the weight of at least one intermediate roll upon the bottom roll on the load distribution in the first nip. |
| Claim: | 9. The method of claim 7, wherein said step of deforming the bottom roll includes establishing uniform load distribution in the first nip and in the nip which is adjacent the first nip. |
| Claim: | 10. The method of claim 7, further comprising the steps of monitoring at least one parameter of calendered material, comparing the monitored parameter with a reference value, and applying to at least one of the top and bottom rolls at least one additional load when the monitored parameter deviates from the reference value so as to eliminate or reduce the deviation. |
| Claim: | 11. The method of claim 2, further comprising the step of calculating the desired configuration of the top roll in accordance with a predetermined algorithm, said deforming step including deforming the top roll in accordance with the results of the calculating step. |
| Claim: | 12. The method of claim 2, further comprising the step of calculating the desired load distribution in the second nip in accordance with a predetermined algorithm, said deforming step including deforming the top roll in accordance with the results of said calculating step. |
| Claim: | 13. The method of claim 2, further comprising the step of compensating, at least in part, for the effect of the weight of the top roll upon the width of the nips. |
| Claim: | 14. 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. |
| Claim: | 15. The method of claim 14, further comprising the step of heating the bottom roll to be a predetermined temperature. |
| Claim: | 16. The method of claim 14, further comprising the step of heating the at least one intermediate roll to a predetermined temperature. |
| Claim: | 17. The method of claim 14 of calendering webs of paper, further comprising the step of moisturizing the webs prior to threading through the nips. |
| Claim: | 18. The method of claim 17, wherein said moisturizing step includes raising the moisture content of paper to between 7 and 18 percent by weight. |
| Claim: | 19. The method of claim 17, wherein said moisturizing step includes raising the moisture content of paper to between 9 and 18 percent. |
| Claim: | 20. The method of claim 19, wherein said moisturizing step includes raising the moisture content of paper to between 9 and 15 percent. |
| Claim: | 21. The method of claim 14, wherein said heating step includes raising the temperature of said portion of the top roll to between 80.degree. and 160.degree. C. |
| Claim: | 22. The method of claim 21, wherein said heating step includes raising the temperature of said portion of the top roll to between 100.degree. and 140.degree. C. |
| Claim: | 23. 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. |
| Claim: | 24. The calender of claim 23, wherein said shell includes first and second end portions and said top roll further comprises first and second rings spacedly surrounding said carrier and rotatably journalled in the respective end portion of said shell, and further comprising means for moving said rings relative to said carrier substantially radially of said shell. |
| Claim: | 25. The calender of claim 24, wherein the moving means for each of said rings includes a first fluid-operated motor adjacent and a second fluid-operated motor remote from said second nip. |
| Claim: | 26. The calender of claim 25, wherein each of said motors includes a piston on the respective ring and a cylinder for the piston on said carrier. |
| Claim: | 27. The calender of claim 26, wherein said cylinders are integral with said carrier and have cylinder chambers for the respective pistons. |
| Claim: | 28. The calender of claim 23, wherein said shell has first and second end portions and further comprising means for locating said end portions in predetermined positions relative to said carrier. |
| Claim: | 29. The calender of claim 28, wherein said locating means includes at least one fluid-operated motor for each end portion of said shell, each of said motors including a cylinder on one of the parts including said carrier and the respective end portion of said shell and a piston provided on the other of said parts and extending into said cylinder, and valve means operable to confine a supply of fluid in the cylinder. |
| Claim: | 30. The calender of claim 23, further comprising a frame for said carrier, said carrier having first and second end portions and said moving means comprising motors provided on said frame and operable to move the end portions of said carrier relative to said intermediate roll, and means for operating said motors. |
| Claim: | 31. The calender of claim 23, further comprising adjustable heating means for said top roll and means for adjusting said heating means so as to maintain the temperature of a portion at least of said top roll within a predetermined range. |
| Claim: | 32. The calender of claim 31, wherein said heating means includes a source of heating fluid and means for connecting said source with the interior of said shell, said adjusting means including means for regulating the flow of heating fluid between said source and said shell. |
| Claim: | 33. The calender of claim 32, wherein said deforming elements include hydrostatic bearing elements and said connecting means includes means for connecting said bearing elements with said source, and further comprising means for regulating the flow of fluid between said source and said bearing elements. |
| Claim: | 34. The calender of claim 23, further comprising adjustable heating means for said at least one intermediate roll. |
| Claim: | 35. The calender of claim 23 for the treatment of paper webs which are threaded through said nips, further comprising means for moisturizing the webs prior to treatment of such webs in said nips. |
| Claim: | 36. The calender of claim 23 for treatment of webs which advance through said nips, further comprising means for monitoring at least one parameter of treated webs, said adjusting means being operative to adjust said deforming elements when the monitored parameter deviates from a desired parameter. |
| Claim: | 37. The calender of claim 36, further comprising adjustable means for heating at least one of said rolls, said adjusting means including means for adjusting said heating means as a function of deviation of monitored parameter from a predetermined parameter. |
| Claim: | 38. The calender of claim 23 for the treatment of material which advances through said nips, wherein said adjusting means comprises means for adjusting said deforming elements in accordance with a predetermined algorithm. |
| Claim: | 39. The calender of claim 38, further comprising adjustable means for heating at least one of said rolls, said adjusting means including means for adjusting said heating means in accordance with said predetermined algorithm. |
| Claim: | 40. The calender of claim 23, further comprising adjustable heating means for said bottom roll, said intermediate roll having a predetermined shape adjacent said second nip. |
| Claim: | 41. 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. |
| Claim: | 42. 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. |
| Current U.S. Class: | 100/38; 100/35; 100/47; 100/74; 100/93RP; 100/162B; 100/163R; 162/206; 1623/601 |
| Current International Class: | B30B 1534; B30B 304 |
| Patent References Cited: | 2908964 October 1959 Appenzeller 3060843 October 1962 Moore et al. 4290351 September 1981 Pav et al. 4311091 January 1982 Pav et al. 4319522 March 1982 Marchioro et al. 4328744 May 1982 Pav et al. 4347784 September 1982 Pav et al. 4370923 February 1983 Schmidt 4389932 June 1983 Pav 4389933 June 1983 Pav 4394793 July 1983 Pav et al. 4425489 January 1984 Pav et al. 4434713 March 1984 Hartwich et al. 4472958 September 1984 Biondetti 4480459 November 1984 Feldman et al. 4480537 November 1984 Agronin et al. 4520723 June 1985 Pav et al. 4625637 December 1986 Pav et al. 4633774 January 1987 Kuosa et al. 4653395 March 1987 Verkasalo 4729153 March 1988 Pav et al. 4757583 July 1988 Pav et al. 4757584 July 1988 Pav et al. 4848119 July 1989 Pav et al. |
| Other References: | "Nipco-Walzen in Superkalandern", Stotz, 1986, pp. 976-983. "Nip Load Uniformity and its control in Multi-Roll Calenders", Mueller et al., Apr. 1986, pp. 88-94. |
| Primary Examiner: | Col, Philip R. |
| Assistant Examiner: | Gerrity, Stephen F. |
| Attorney, Agent or Firm: | Kontler, Peter K. |
| رقم الانضمام: | edspgr.05029521 |
| قاعدة البيانات: | USPTO Patent Grants |
| الوصف غير متاح. |