JPH10202175A - Method for drying coating of paper web and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the use of high temperature for an air supply to a turning device and the removal of a large amount of high temperature air to be exhausted from the area under control without adversely affecting the traveling properties of a paper web, and further, prevent a heated air from being discharged unlimitedly into a machine chamber. SOLUTION: The coating of a paper web W is dried, in a non-contact manner, by the blowing of a air from drying devices 30, 40 positioned on both sides of the paper web W, and the direction in which the paper web W travels is turned by the blowing of the air for drying. An exhaust from the drying device 30 is removed by a common exhaust device 34 close to the paper web W. Both turning device 20 and drying device 30 arranged alongside of the turning device 20 are disposed in a common enclosure 25, so that the exhaust is prevented from penetrating into an ambient space.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drying method in which a running direction of a paper web is turned by a spray generated by a turning device in a non-contact manner, and a coating on the paper web is contactlessly provided on both sides of the paper web. The present invention relates to a method for drying a coating such as a paper web which is dried by spraying of an apparatus.

Further, the present invention has a turning device for changing a running direction of a paper web or the like in a non-contact manner, and a drying device for drying a coating of a web or the like in a contactless manner. The present invention relates to a device for drying a coating on a paper web or the like, comprising a nozzle for performing spraying and an exhaust device for removing exhaust gas from the vicinity of the paper web or the like.

[0003]

BACKGROUND OF THE INVENTION As is well known, in some coating processes it is necessary to be able to change the running direction of the web in a contactless manner after the coating has been applied to the web surface and before the coating has set. . Often, these processes also require that the web be dried quickly and efficiently to contact dryness, not for quality or equipment reasons. However, at the same time, it is necessary to maintain good running properties of the web. As is well known, this type of process is often performed using a turning device and also using an infrared dryer and possibly an air dryer. However, in such a case, the drying equipment is subject to some constraints that are dictated by the process and equipment that affect the length of the machine. At the same time, there is a difficulty in running the equipment. One example of this type of problem is a free draw of at least about 0.5 meters between the turning device and the subsequent drying device, which is commonly used in currently used systems.

[0004]

With respect to the prior art relating to turning and drying equipment of the type described above, priority is given to Finnish Patent Application No. 943657 (German Patent Application No. 4400158 and European Patent Application No. 93112695). See It describes an apparatus in which a paper web is colored by two rolls arranged in parallel to each other, these rolls forming a gap between the rolls and passing the paper through the gap. The apparatus is provided with at least one jet printing device for applying the color layer to the mantle surface of the rolls and transferring the color layer from the roll mantle surface to one side of the paper web in the gap between the rolls. I do. The apparatus also includes a carrier air beam, which creates a cushion of carrier air between the paper web and the face of the carrier air beam facing the paper web. The conveying air beam described above is configured to change the direction of the paper web at least once after the gap between the rolls. In this prior art approach, at least one carrier air beam is connected immediately after the gap between the rolls and is spaced apart from the gap formed by the two rolls.

With respect to the prior art, see also EP 0507
See Issue 218. This describes a drying unit in which the web is turned by a web running device in a non-contact manner, and a drying device is disposed after the web running device and away from the turning device.

[0006] With regard to the prior art, reference can also be made to DE-OS 44 15 581. This describes a non-contact air dryer provided outside the turning sector of the turning roll.

It is an object of the present invention to provide a method and apparatus for drying a coating on paper web or the like that eliminates most of the disadvantages associated with the prior art or at least minimizes the catastrophic effects of the above-mentioned disadvantages. .

[0008]

SUMMARY OF THE INVENTION In order to solve the above and other objects which will become apparent, the method according to the invention has the following main features. That is, the running direction of the paper web or its equivalent is turned by dry spraying,
The exhaust of the turning device and the drying device provided on the turning device side is removed by a common exhaust device from the vicinity of the paper web or its equivalent, and the drying device provided on the turning device and the turning device side is provided in a common box. Located below the structure, this prevents exhaust from entering the surrounding space.

On the other hand, the turning device according to the present invention has the following features. That is, a turning device for the paper web or its equivalent, and a drying device arranged on the same side as the turning device for the paper web or its equivalent are arranged under a common box structure, and this device is a turning device. The drying device, including the means for generating a dry spray, arranged below the turning device and the turning device under the common box structure, has a common exhaust member.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail with reference to the accompanying drawings, but the invention is not restricted to the details of these descriptions.

As shown in FIG. 1, an apparatus 10 is arranged on a paper web W, which comprises a turning device 20 in a box 25 and a drying device 30 which immediately follows the turning device. Is provided. The diverting device 20 has a nozzle 21 from which air is blown for contactless diverting of the web W. Drying equipment 30
Has a nozzle 31 from which air is blown to dry the coating on the web W. In the drying device 30, an exhaust opening is provided between the nozzles 31, through which moisture is removed from between the web W and the drying device 30. Air supplied by the turning device 20 is also removed from the area of the nozzle 31 of the drying device 30, preferably through an exhaust opening in the first end. Under the paper web W, a drying device 40
This is provided with nozzles 41 and an exhaust opening between them for removing moisture. Hot air blows out from the nozzle 41 to dry the coating of the paper web W. The lower drying device is also included in the box structure 45. The lower dryer 40 extends into the region of the upper dryer 30 and also partially or entirely into the region of the turning device. Air is sent into the turning device 30 from the duct 22 by the blower 23. Air can also be pumped from outside the device through the duct 26 to the turning device 20, the adjustment plate of which is indicated by the reference numeral 27. The diverting device 20 uses the combined return air of the drying device and the diverting device, and the returned air is sent along the duct 24 through the adjusting plate 29. Drying air is sent to drying devices 30 and 40 through ducts 32 and 42. Grating gates for air supply per drying unit, see numbers 33 and 43
Indicated by Air is sent into the burner system through the combustion air blower 63, and the gas flow to the burner device 62 is adjusted by the adjusting valve 64. The air from this burner device is further sent along duct 51 to drying devices 30 and 40. By opening the open / close grid type gate 56 through the duct 55,
Further, by closing the open / close lattice type gates 54 and 53 at the same time, a short circulation system can be passed. This short circuit is used during periods such as production interruptions when the entire system should not be shut down. Return air from the upper drying device 30 and the lower drying device 40 is fed from the ducts 44 and 34 through the adjusting grid type gates 35 and 46 to the duct 52, and from there to the turning device through the adjusting gate 29, or exhausted. Through the regulating gate 57 to the exhaust duct 58, or as a return circulation to the blower 61 through the guide blade adjustment device 59, where the return air is returned to the circulation. The adjustment lattice type gates 37 and 38 can adjust the balance of the exhaust air of the drying device 30 and the turning device 20.
The runnability of the web in the area between the turning devices can be influenced. As for the supply device of the air to the turning device 20, an adjusting grid type gate 28 is attached in front of the blower 23.

The embodiment shown in FIG. 2 is substantially similar to that shown in FIG. 1, and the same reference numerals are used for similar elements. Compared with the embodiment shown in FIG. 1, in the embodiment shown in FIG. 2, a gap 16 is provided between the turning device 20 and the drying device 30 through which the exhaust gas passes from the turning device 20 to the drying device 30.
Is sent to exit 34. The turning devices 20 and 30 are placed inside the same box 25, a partition wall 12 is attached between the turning device portion 20 and the drying device portion 30, and an opening 15 is provided in this, and through this opening, Exhaust gas is sent, thus enhancing run stability and controlling exhaust equipment. By sending part of the exhaust of the diverting device through the gap 15, an unfavorable air flow from a driving point of view is avoided. The lower drying device 40 is the same as that shown in FIG. 1 except that it extends only to the region of the upper drying device 30, even if it can also be extended to the region of the turning device. The gap between the turning device 20 and the drying device 30 is a perforated plate,
It is covered with a net 17 or the like, so that the paper piece can be prevented from entering the above-mentioned gap according to the return air.

The embodiment shown in FIG. 3 is similar to that shown in FIGS. 1 and 2, and the same reference numbers are used for similar elements. In this embodiment, compared to the embodiment shown in FIG.
An additional drying device 13 is mounted in the space 16 between the turning device 20 and the drying device 30. This additional drying device dries the web W in this gap, which can be, for example, an infrared dryer as shown in the figure.
In this embodiment, the exhaust of the turning device 20 is supplied to the infrared dryer 13.
To the outlet of the drying device 30 from both sides of the
In addition, the air is sent from a space 15 provided in the partition wall 12 to an outlet of the drying device through a space 14 above the infrared dryer 13. The lower drying device 40 is the same as the drying device shown in FIG.

The PI diagram shown in FIG. 4 illustrates one embodiment of the automated configuration and the adjustment of the control of the process and drying equipment. In this figure, similar elements have the same reference numbers as used in FIGS. 1-3. The amount of air for the turning device is adjusted by the guide blade adjusting device 28 or by adjusting the rotational speed 73 of the blower. This amount of air is adjusted based on the pressure measurements of the air cushion 72 and the air intake 71 so that a sufficient and desired pressure and thickness of air cushion can be obtained from the viewpoint of web turning.

The exchange air entering the diverting device is one coming from the machine room, one coming from the outside air, or preheated air, the amount of which is adjusted by the adjusting plate 27. The amount of exhaust air from the drying device is adjusted by the adjusting plate 57. These two
By adjusting the ratio of the plates, an air balance in the drying device is ensured.

The other adjustment parts of the air-supported dryer are the same as the traditional adjustment principles used in similar conventional air-supported dryers.

FIG. 5A is a schematic diagram of an apparatus according to the present invention, with the upper portion designated by reference numeral 10 and the lower portion designated by reference numeral 11. The paper web W travels between these elements without contact,
Thereby, the coating of the paper web W is dried, and the web is turned. 5B to 5D show the tail of the web W.
Show some examples how to open the device when multiplied by the W _I. In the embodiment shown in FIG. 5B, the lower device 11 moves downward while remaining parallel, for example, along a guide (not shown) attached to the frame structure. In the embodiment shown in FIG. 5C, the upper device 10 rotates about the center point of the turning device portion, so that the web turning is properly maintained during web loading, and the drying device does not affect the web loading. . In the embodiment shown in FIG. 5D, a hinge is provided on either the drive or monitor edge of the lower device 11 and the device rotates about the hinge axis when the web is hung on the tail.

The present invention has been described with reference only to some embodiments, and the present invention is not limited to those contents. Many changes and modifications can be made within the spirit of the invention as defined in the following claims.

[0019]

According to the present invention, drying is most commonly performed by a turning device and an air dryer, which are physically made as a single device, thereby freeing up prior art devices. It is possible to eliminate some of the free draws in prior art equipment where draws created a danger of runnability.

In the solution according to the invention, both the length of the turning device and the length of the free draw which existed in prior art systems are used for drying. In such a situation, drying can begin about 1.2 to 1.5 meters earlier than in the prior art.

The solution according to the invention can also use circulating hot air in the turning device. This is because the exhaust of the turning device is collected together with the exhaust of the air-supporting drying device. In the prior art system, the turning device uses, in principle, cold air taken from the machine room, in which case the drying effect of the turning device is negligible. The use of hot air in a conventional turning device imposes heat and moisture on the machine room, which is uneconomical in terms of energy consumption,
It can be dangerous from a work safety standpoint.

According to the present invention, the web turning device and the web drying device are combined to separate the common return air region into a plurality of regions, separately from the traveling characteristics and the air control characteristics. , So that the air can be adjusted individually. The combination of the turning and drying functions is achieved by including the turning function in a conventional air-supported drying box.
Alternatively, this is achieved by providing a common insulated housing for suctioning the return air in each individual device.

In the device according to the invention, high temperatures can be used for the air supply of the turning device, since the turning device and the drying device are integrated in one device box. Desirably, the temperature of the air supply of the diverter is about 100-300 ° C.
Since the air discharged from the diverting device is sucked into the air system as return air, a large amount of high-temperature air can be removed from the area while controlling the traveling performance without affecting traveling performance. At the same time, the danger at the time of operation, which is caused by the unlimited discharge of the hot air into the machine room, is eliminated.

The drying section of the apparatus according to the invention can be arranged substantially immediately after the turning section or at some distance, independent of running or installation reasons, as required. A suitable distance in the installation according to the invention is
Typically about 100-700 mm. According to the invention, this area can be provided with features that promote runnability and / or drying, such as drying and / or exhaust and / or profiling devices, or other similar devices.

The air-supporting device section used in connection with the device according to the invention can be achieved in a conventional manner known per se or by the principle of high capacity. In the latter case, the temperature can be up to 450 ° C and the speed can be up to 100 meters per second. Otherwise, the air support device part is known per se from the prior art to a person skilled in the art.

In the device according to the invention, the combined return air of the drying section and the diverting section is used as or part of the air supply for the diverting device. A part of this air supply can also be taken from the machine room or from the outside air or as air preheated by heat recovery for the diverting device. This air taken in from the outside simultaneously serves as a common exchange air for the entire drying unit.

In connection with the device according to the invention, the temperature of the air supply for the turning device can be measured and adjusted automatically.
At the same time, the amount of air in the turning device can be checked and the amount of air used in the turning device can be adjusted. Further, the degree of vacuum of the united box can be automatically measured and adjusted.

When the tail is hung, the combination device is desirably operated, and the turning device is operated to ensure non-contact turning of the web. However, the drying unit is switched off or switched to a short circulation system. deep. During tailing, circulating air, or air from the machine room or the outside air, or a suitable combination of circulating air and machine room / outside air can be used as the air supply for the turning device.

[Brief description of the drawings]

FIG. 1 is a schematic view of an embodiment of the device according to the present invention.

FIG. 2 shows a second embodiment of the device according to the invention.

FIG. 3 is a schematic view of a third embodiment of the device according to the invention.

FIG. 4 is a diagram showing a specific example of a PI diagram of the device according to the present invention.

FIG. 5 is a schematic diagram of some embodiments of how the apparatus of the present invention opens during webbing.

[Explanation of symbols]

 20 Turning device 25 Common box structure 30, 40 Drying device 34 Common exhaust device

Claims (26)

[Claims] 1. The running direction of a paper web is diverted in a contactless manner by spraying generated by a turning device, and the coating of the paper web is contactlessly sprayed by a drying device arranged on both sides of the paper web. A method of drying a coating of a paper web or the like to be dried, the method comprising: turning a running direction of the paper web or an equivalent thereof by dry spraying; and drying the turning device and a drying device disposed on a side of the turning device. Is removed from the vicinity of the paper web or its equivalent by a common exhaust device, and the turning device and a drying device provided on the side of the turning device are disposed under a common box structure, and A method for drying a coating on a paper web or the like, wherein the exhaust gas is prevented from entering a space around the exhaust gas. 2. The method according to claim 1, wherein the air supply for the diverting device comprises air taken in from a return air duct of the drying device and air taken in from a machine room or outside, or preheated exchange air. A method for drying a coating, characterized in that it is carried out as a mixture of: 3. The method according to claim 1 or 2, wherein the air removed from the turning device is controlledly sent from an area between the turning device and the drying device,
A method for drying a coating, comprising forming return air of the drying device. 4. The method according to claim 1, wherein the web is dried by a drying device substantially immediately after the turning of the web by the turning device. Drying method. 5. The method according to claim 1, wherein the method further comprises, after the turning device, diverting a web through an intermediate space and passing at least exhaust air from the turning device through the intermediate space. Coating characterized in that a part is fed into the box structure of the drying device through an opening arranged between the intermediate space and the box of the drying device and / or through an opening provided for a web. Drying method. 6. The method according to claim 1, wherein the balance between the return air of the deflecting device and the return air of the drying device is set by means of a regulating plate. How to dry the coating. 7. The method according to claim 1, wherein at least a part of the exhaust gas from the turning device is sent to the return air space of the drying device through the intermediate space and the opening. A method for drying a coating, characterized in that an undesired flow of air is reduced at the web opening between the turning device and the drying device, in terms of runnability. 8. The method according to claim 1, wherein the paper web is arranged under the same box structure in a space between the turning device and the drying device. A method for drying a coating, comprising drying with a radiation device. 9. The method according to claim 8, wherein the infrared radiation device is realized as a profiling device. 10. The method according to claim 1, wherein the temperature of the turning device is 25 to 300 ° C.
And drying the coating, preferably by blowing air at 100 to 300 ° C. 11. The method according to claim 1, wherein the temperature of the air blown from the drying device is
100 to 450 ° C, and air is 20 to 100 meters per second,
Preferably, the coating is blown at a temperature of 150 to 400 ° C at a speed of 40 to 75 meters per second. 12. The method according to claim 1, wherein the air used as air supply blown from the diverting device is at least partially circulating air returning from the drying device. How to dry the coating. 13. The method according to claim 1, wherein air used as air blown from the turning device is circulated from the drying device and taken in from a machine room or from outside. A method of drying the coating, characterized in that the temperature of the blowing air of the diverting device is adjusted by the ratio of these airs. 14. The method according to claim 1, wherein the air used as the air blown from the diverting device is the dry air supplied to the drying device, the machine room, or the outside air. A method for drying a coating, characterized in that it is a mixture with air taken in from the air or with preheated exchange air. 15. The method according to claim 1, further comprising, when tailing the web, a drying device connected to the turning device to form a part of the drying device. A method for drying a coating, comprising rotating the web away from the web about a point. 16. The method according to claim 1, wherein the tailing of the web is arranged on a side of the web opposite to the turning device and forms part of the drying device. A method for drying a coating, comprising: moving a drying device away from the web. 17. The method according to claim 1, wherein the tailing of the web is arranged on a side of the web opposite the turning device and forms part of the drying device. A method of drying a coating, comprising rotating a drying device away from the web about an edge parallel to a machine direction of the drying device. 18. A turning device for changing a running direction of a paper web or an equivalent thereof in a non-contact manner, and a drying device for drying a coating of the web or the equivalent in a contactless manner, wherein the turning device and the drying device are provided. A drying apparatus for coating a paper web or the like, comprising: a nozzle for performing spraying; and an exhaust device for removing exhaust air from the vicinity of the paper web or the equivalent thereof. A turning device and a drying device located on the same side of the paper web or its equivalent as the turning device are arranged below a common box structure, the device including means for performing dry spraying with the turning device. , The turning device,
A drying device for coating a paper web or the like, wherein the drying device disposed together with the turning device below the common box structure has a common exhaust member. 19. The drying device according to claim 18, wherein
Coating characterized in that the air supply for the diverting device is a mixture of air taken from the return air duct of the drying device with air taken from the machine room or from the outside, or with preheated exchange air. Drying equipment. 20. The drying device according to claim 18, wherein
Apparatus for drying a coating, characterized in that the air exiting the diverting device is controlled and sent out of the area between the diverting device and the drying device and constitutes the return air of the drying device. 21. The drying device according to claim 18, wherein the turning device and the drying device disposed below the box structure are disposed directly and alternately in the traveling direction of the web. An apparatus for drying a coating, comprising: 22. The coating device according to claim 18, wherein the turning device and the drying device disposed below the box structure are separated from each other by a certain distance. Drying equipment. 23. The drying device according to claim 18, wherein an infrared radiation device is provided between the turning device disposed under the box structure and the drying device. Characteristic coating drying equipment. 24. The drying device according to claim 23,
An apparatus for drying a coating, characterized in that said infrared radiation device is realized as a profiling device. 25. The drying device according to claim 18, wherein a drying device arranged on the opposite side of the web from the turning device has a region of the drying device on the opposite side,
And an apparatus for drying the coating, characterized in that it extends over part, and possibly all, of the area of the turning device. 26. The drying device according to claim 18, wherein the drying device arranged on the side of the web opposite to the turning device extends into the area of the drying device on the opposite side. An apparatus for drying a coating, comprising: