Claims
- 1. A drying section of a machine for producing a material web comprising:at least one web guidance device; and at least one wire arranged to guide the material web through the at least one web guidance device; and said at least one web guidance device is arranged before, relative to a web travel direction, a first drying cylinder and after a last press nip, wherein said at least one web guidance device is structured and arranged to direct pressurized gas at the material web so that, in a web travel direction, the material web is alternately lifted from said at least one wire and resting against said at least one wire.
- 2. The drying section in accordance with claim 1, wherein the material web comprises one of a paper and cardboard web.
- 3. The drying section in accordance with claim 1, wherein said at least one web guidance device is driven by pressurized gas and is formed as an airborne web dryer.
- 4. The drying section in accordance with claim 3, wherein said at least wire is guided in a straight line through said pressurized gas-driven web guidance device.
- 5. The drying section in accordance with claim 1, wherein said at least one web guidance device comprises a plurality of nozzles arranged one behind the other in the web travel direction for directing said pressurized gas at the material web.
- 6. The drying section in accordance with claim 5, wherein said plurality of nozzles are positioned on both sides of said at least one wire.
- 7. The drying section in accordance with claim 5, wherein said plurality of nozzles comprises nozzle banks extending across a web width.
- 8. The drying section in accordance with claim 1, wherein said at least one web guidance device is arranged before a first drying cylinder.
- 9. The drying section in accordance with claim 8, wherein said at least one web guidance device comprises a pressurized gas driven web guidance device.
- 10. The drying section in accordance with claim 1, wherein said pressurized gas is air.
- 11. The drying section in accordance with claim 1, further comprising at least one impingement dryer with a drying hood, wherein at least one impingement dryer subjects the material web to at least one of hot air and hot steam impingement.
- 12. The drying section in accordance with claim 11, further comprising at least one support or suction roll associated with said at least one impingement dryer, wherein the material web is guided over said at least one support or suction roll.
- 13. The drying section in accordance with claim 12, wherein said at least one support or suction roll is arranged so that, as the material web is guided over said at least one support or suction roll, the material web is subjected to the at least one of the hot air and hot steam impingement.
- 14. The drying section in accordance with claim 12, wherein said at least one impingement dryer is located before a first drying cylinder.
- 15. The drying section in accordance with claim 12, wherein said at least one impingement dryer is located behind said at least one web guidance device in the web travel direction.
- 16. The drying section in accordance with claim 1, wherein at least one of when leaving a first drying cylinder and a first time pulled off a smooth heated surface, the material web has a dry content greater than at least about 58% to about 65%.
- 17. The drying section in accordance with claim 1, wherein said at least one web guidance device is located subsequent to a last pressing nip of a pressing section in the web travel direction.
- 18. The drying section in accordance with claim 1, further comprising an impingement dryer and at least one support or suction roll associated with said impingement dryer,wherein, subsequent to a last pressing nip of a pressing section, the material web is guided through said at least one web guidance device and is guided over said at least one support or suction roll before being guided to a first drying cylinder.
- 19. The drying section in accordance with claim 1, further comprising an impingement dryer through which the material web is guided,wherein said at least one web guidance device is formed as an airborne dryer, and wherein a drying speed in a region of at least one of said airborne web dryer and said impingement dryer is regulatable via at least one of a pressurized gas temperature, speed, and moisture.
- 20. The drying section in accordance with claim 1, wherein an air permeability of said at least one wire is greater than approximately 300 cfm.
- 21. The drying section in accordance with claim 20, wherein the air permeability is greater than approximately 500 cfm.
- 22. The drying section in accordance with claim 1, wherein the material web departing from a last pressing nip of the pressing section is guided to a first drying cylinder in a closed draw.
- 23. The drying section in accordance with claim 1, wherein the material web is transferred from a pressing section directly to said at least one wire.
- 24. The drying section in accordance with claim 1, wherein said at least one web guidance device comprises a plurality of web guidance devices and said at least one wire comprises a plurality of wires respectively associated with each of said plurality of web guidance devices.
- 25. The drying section in accordance with claim 1, wherein the material web is transferred from a pressing section to said at least one wire via at least one transfer belt.
- 26. The drying section in accordance with claim 1, wherein a felt is arranged through a last pressing nip of a pressing section, and the material web is transferred to said at least one wire from said felt.
- 27. The drying section in accordance with claim 1, wherein the material web is removed directly from a pressing roll of a last pressing nip of a pressing section.
- 28. The drying section in accordance with claim 1, further comprising at least one impingement dryer, and said at least one web guidance device comprises an airborne web dryer,wherein at least one of: said at least one web guidance device comprises a plurality of web guidance device and said at least one impingement dryer comprises a plurality of impingement dryers.
- 29. The drying section in accordance with claim 1, wherein said at least one web guidance device is oriented to guide the material web in a substantially horizontal direction.
- 30. The drying section in accordance with claim 1, wherein said at least one web guidance device is oriented to guide of the material web in a substantially vertical direction.
- 31. The drying section in accordance with claim 1, wherein said at least one web guidance device is oriented to guide the material web in a generally diagonally upward direction.
- 32. The drying section in accordance with claim 1, wherein said at least one web guidance device is oriented to guide the material web in a generally diagonally downward direction.
- 33. The drying section in accordance with claim 1, wherein said at least one web guidance device comprises a plurality of web guidance devices, andwherein at least some of said plurality of web guidance devices are associated with said at least one wire.
- 34. The drying section in accordance with claim 1, wherein said at least one web guidance device comprises a plurality of web guidance devices, andwherein said at least one wire is guided through said plurality of web guidance devices.
- 35. The drying section in accordance with claim 1, wherein said at least one web guidance device comprises a plurality of web guidance devices arranged to follow one another to guide the material web on said at least one wire, and said dryer section further comprises:at least one of suction rolls, transfer foils, and suction boxes which are located at least one or before, between, and after said plurality of web guidance devices.
- 36. The drying section in accordance with claim 1, wherein, in said at least one web guidance device, at least one of:the pressurized gas is directed at a surface of the material web facing away from said at least one wire and a vacuum is applied to a surface of the material facing said at least one wire.
- 37. The drying section in accordance with claim 1, wherein said at least one web guidance device comprises nozzle banks positioned on a side of said at least one wire opposite the material web to direct said pressurized gas toward the material web and vacuum boxes arranged between said nozzle banks.
- 38. The drying section in accordance with claim 1, wherein the pressurized gas directed at the material web has a temperature of in a range of approximately 20° C. to approximately 150° C.
- 39. A drying section of a machine for producing a material web comprising:at least one airborne web dryer with at least one wire positioned at least one of (a) between a last pressing nip of a pressing section and a first drying cylinder and (b) inside a predrying section, wherein the at least one airborne web dryer is structured and arranged to direct pressurized gas at the material web so that, in a web travel direction, the material web is alternately lifted from said at least one wire and resting against said at least one wire.
- 40. The drying section in accordance with claim 39, wherein the material web comprises one of a paper and cardboard web.
- 41. An airborne web dryer comprising:a single wire arranged to support the web, wherein said single wire is arranged to transport the web after a last press nip and before a first drying cylinder.
- 42. The airborne web dryer in accordance with claim 41, further comprising a plurality of nozzles arranged in a web travel direction so that the material web is alternatingly lifted off the wire and resting on the wire.
- 43. The airborne web dryer in accordance with claim 41, wherein the material web comprises one of a paper and cardboard web.
- 44. A process for transporting a material web through a drying section of a machine that includes at least one web guidance device and at least one wire, said process comprising:pressing the material web in a last press nip; guiding the material web from the last press nip through the at least one web guidance device on the at least one wire; directing pressurized gas at the material web, whereby, in a web travel direction, the material web is alternately lifted from said at least one wire and resting against said at least one wire; and guiding the material web from the at least one guidance device to a first drying cylinder.
- 45. The process in accordance with claim 44, further comprising suctioning, between the areas at which pressurized gas is directed in the web travel direction, the material web toward the at least one wire.
Priority Claims (1)
Number |
Date |
Country |
Kind |
100 24 358 |
May 2000 |
DE |
|
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority under 35 U.S.C. §119 of German Patent Application No.100 24 358.4, filed on May 17, 2000, the disclosure of which is expressly incorporated by reference herein in its entirety.
US Referenced Citations (8)
Foreign Referenced Citations (1)
Number |
Date |
Country |
2942030 |
May 1980 |
DE |