Processing equipment for overcoming warping of paper edges

Abstract

The invention provides processing equipment for overcoming warping of paper edges. The processing equipment comprises a water feeding device, a drying device and a cooling device which are sequentially arranged along a raw paper flowing line, the water feeding device is used for providing moisture for the raw paper, the drying device is used for drying the raw paper soaked with the moisture, and the cooling device is used for cooling the dried raw paper. According to the processing equipment for overcoming deckle edge warping provided by the embodiment of the invention, by designing a structure with the water feeding device, the drying device and the cooling device, the problem of deckle edge warping can be effectively solved, the smooth and glossy cross section of the zero-plastic paper is realized, and the problems of back papermaking and quality abnormality are reduced; the problems of sharp increase of rejection rate, increase of energy consumption, failure of packaging and sealing, printing deviation, reduction of market trust, increase of carbon footprint and the like caused by hemming of finished products in the production process of zero plastic paper are solved.

Description

Technical Field

[0001] The present application relates to the technical field of papermaking equipment, and in particular to a processing equipment for overcoming paper edge warping. Background Art

[0002] With growing environmental awareness, reducing plastic pollution and promoting sustainable development have become a global consensus. "Plastic-free paper" has emerged as an innovative, environmentally friendly material designed to replace traditional plastic products, reduce environmental impact, and promote green living. Plastic-free paper is a type of paper or paper-based composite material designed to completely or partially replace the use of plastic and have minimal environmental impact throughout its entire lifecycle (from production, use, to disposal). It differs from traditional paper products in that it incorporates environmentally friendly concepts and technological innovations in its raw material selection, production processes, performance, and recycling processes, effectively replacing plastic products. In the plastic-free paper processing industry, edge curling is a core issue limiting product quality stability. Curling of the paper edge (i.e., curling) is a frequent occurrence during processing, significantly reducing the yield of the finished product. According to statistics, approximately 30% of plastic-free paper manufacturers worldwide experience scrap rates exceeding 8% due to edge curling, with some high-end product lines experiencing scrap rates as high as 15%. Curling occurs when the edges of paper warp upward or downward due to uneven stress distribution or temperature and humidity fluctuations. This not only affects the paper's flatness but also compromises the accuracy of subsequent processes such as printing, die-cutting, and laminating. Curling also weakens the paper's mechanical properties, reducing its tensile strength and burst resistance by 20%-30%, directly impacting the lifespan of end products. This has become a major technical bottleneck hindering the industry's transition to higher-value-added products.

[0003] Although the issue of paper curling has garnered widespread industry attention, a systematic solution remains unresolved, and mature, specialized equipment is even more scarce. Traditional papermaking techniques used to prevent curling (such as edge humidification and tension gradient control) for ordinary paper have limited effectiveness in the context of plastic-free paper. This is because plastic-free paper has a looser fiber structure, a hygroscopic expansion coefficient 40%-60% higher than traditional paper, and lacks the stress-buffering effect of a plastic coating. Paper curling severely hinders the industrialization of plastic-free paper. Frequent production downtime and equipment idling increase energy costs by 18%-25%, and processing scrap rates exceed theoretical values by 3-5 percentage points. At the end-use application level, curling increases the risk of seal failure in food packaging by 40%, and printing overprint errors exceed tolerance standards by twice, directly raising market concerns about the reliability of the material. This technical bottleneck not only drives up production costs but also creates a vicious cycle of "performance deficiencies, market resistance, and delayed technological iteration," becoming a key obstacle to the industry's green transformation. Summary of the Invention

[0004] An embodiment of the present application provides a processing device for overcoming paper edge warping, the processing equipment comprising: a water supply device, a drying device, and a cooling device arranged in sequence along the flow line of the base paper; the water supply device is used to provide moisture to the base paper, the drying device is used to dry the base paper after being soaked with moisture, and the cooling device is used to cool the dried base paper.

[0005] In some optional embodiments, the water supply device includes a bracket, a roller and a water trough, the roller is rotatably connected to the bracket, the water trough is fixed to the bracket and is used to hold water, the roller is partially immersed in the water in the water trough, the raw paper to be processed passes through the roller and drives the roller to rotate, thereby transferring the water on the roller to the raw paper to be processed.

[0006] In some optional embodiments, the roller includes a first roller and a second roller, the first roller and the second roller are arranged in parallel and rollingly attached, the first roller is used to contact the base paper to be processed and can rotate driven by the base paper, the second roller rotates driven by the first roller, and the second roller is partially immersed in the water in the water tank.

[0007] In some optional embodiments, a first adhesive layer is provided on the surface of the first roller, and the first adhesive layer is in rolling contact with the second roller.

[0008] In some optional embodiments, a second rubber layer is provided on the surface of the second roller, and the second rubber layer is in rolling contact with the first rubber layer of the first roller; wherein the hardness of the first rubber layer is less than the hardness of the second rubber layer.

[0009] In some optional embodiments, the water supply device further includes a compression adjustment unit, and the compression adjustment unit is used to adjust the compression force between the first roller and the second roller.

[0010] In some optional embodiments, the compression adjustment unit includes a driving member, a base and a connecting arm, the driving member and the base are respectively connected to the bracket, the middle part of the connecting arm is hinged to the base, and the two ends of the connecting arm are respectively connected to the driving member and the rotating shaft of the first roller.

[0011] In some optional embodiments, the driving member includes any one of a driving cylinder, a linear motor, a driving hydraulic cylinder and a driving motor.

[0012] In some optional embodiments, the water supply device further includes a scraper, which is provided corresponding to the outer surface of the second roller and is used to control and adjust the amount of water on the outer surface of the second roller.

[0013] In some optional embodiments, the water supply device further includes a scraper adjustment unit, which is connected to the scraper and is used to control and adjust the distance between the scraper and the outer surface of the second roller.

[0014] The processing equipment for overcoming paper edge warping provided in the embodiment of the present application can effectively solve the problem of paper edge warping by designing a structure with a water supply device, a drying device and a cooling device, achieve a smooth and glossy cross-section of zero-plastic paper, reduce the problems of copyback and quality abnormalities, and solve the problems of a surge in scrap rate, increased energy consumption, packaging seal failure, printing deviation, reduced market trust and increased carbon footprint caused by curling of finished products in the production process of zero-plastic paper. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0016] Figure 1 This is a schematic diagram of the overall structure of an embodiment of a processing device for overcoming paper edge warping according to the present application;

[0017] Figure 2 yes Figure 1 A schematic structural diagram of the processing equipment from another perspective in the embodiment;

[0018] Figure 3 yes Figure 1 Schematic diagram of the structure of the water supply device in the embodiment. DETAILED DESCRIPTION

[0019] The present application will be further described in detail below in conjunction with the accompanying drawings and examples. It is particularly noted that the following examples are only intended to illustrate the present application and are not intended to limit the scope of the present application. Similarly, the following examples are only some examples of the present application and not all examples. All other examples obtained by those of ordinary skill in the art without creative work are intended to fall within the scope of protection of this application.

[0020] The terms "first", "second" and "third" in the embodiments of the present application are used only for descriptive purposes and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second" and "third" may explicitly or implicitly include at least one of such features. In the description of the present application, "multiple" means at least two, for example, two, three, etc., unless otherwise clearly and specifically defined. All directional indications in the embodiments of the present application (such as up, down, left, right, front, back...) are only used to explain the relative positional relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly. The terms "including" and "having" in the embodiments of the present application and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or components inherent to these processes, methods, products or devices.

[0021] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0022] In response to the problems of curling of finished products during the production process of paper products such as zero-plastic paper, which leads to a surge in scrap rates, increased energy consumption, packaging seal failure, printing deviation, reduced market trust, and an increased carbon footprint, the embodiments of the present application provide a device to overcome paper edge warping, eliminate the curling caused by the uneven internal stress distribution generated during the production drying and rewinding process of zero-plastic paper, and then shape the paper through the sequential action of drying and cooling cylinders, fundamentally solving the problem of paper edge warping, achieving a smooth and glossy cross-section of zero-plastic paper, and reducing the problems of copyback and quality abnormalities.

[0023] Please also refer to Figure 1 and Figure 2 , Figure 1 This is a schematic diagram of the overall structure of an embodiment of a processing device for overcoming paper edge warping in the present application. Figure 2 yes Figure 1 A structural schematic diagram of the processing equipment in the embodiment from another perspective; the processing equipment for overcoming paper edge warping in the embodiment of the present application includes but is not limited to a water supply device 100, a drying device 200 and a cooling device 300.

[0024] Specifically, the water supply device 100, the drying device 200 and the cooling device 300 are arranged along the flow line of the base paper 88 ( Figure 1 The water supply device 100 is used to provide moisture to the base paper, the drying device 200 is used to dry the base paper 88 after being soaked with water, and the cooling device 300 is used to cool the base paper 88 after being dried.

[0025] See also Figure 3 , Figure 3 yes Figure 1 A schematic structural diagram of the water supply device in the embodiment, wherein the water supply device 100 in this embodiment includes a bracket 110, a roller 120 and a water trough 130, the roller 120 is rotatably connected to the bracket 110, the water trough 130 is fixed to the bracket 110 and is used to hold water, the roller 120 is partially immersed in the water in the water trough 130, the raw paper 88 to be processed passes through the roller 120 and drives the roller 120 to rotate, thereby transferring the water on the roller 120 to the raw paper 88 to be processed.

[0026] Optionally, the roller 120 in the embodiment of the present application includes a first roller 121 and a second roller 122. The first roller 121 and the second roller 122 are arranged in parallel and rollingly attached. The first roller 121 is used to contact the base paper 88 to be processed and can rotate driven by the base paper 88. The second roller 122 rotates driven by the first roller 121, and the second roller 122 is partially immersed in the water in the water tank 130.

[0027] A first adhesive layer 1210 is provided on the surface of the first roller 121, and the first adhesive layer 1210 is in rolling contact with the second roller 122; a second adhesive layer 1220 is provided on the surface of the second roller 122, and the second adhesive layer 1220 is in rolling contact with the first adhesive layer 1210 of the first roller 121; wherein the hardness of the first adhesive layer 1210 is less than the hardness of the second adhesive layer 1220.

[0028] The lower half of the second roller 122 is immersed in water. As the second roller 122 moves, it carries water to the first roller 121. The moisture adhering to the surface of the first roller 121 then penetrates into the interior of the paper, completing the water supply. Alternatively, for paper with a wider width or a higher dryness, the first roller 121 and the second roller 122 can each be equipped with a pair of gear motors to maintain counter-rotating motion. This significantly increases the amount of water carried by the first roller 121 due to the greater difference in speed between the two rollers in counter-rotating motion.

[0029] Optionally, the water supply device 100 in this embodiment further includes a compression adjustment unit 140, which is used to adjust the compression force between the first roller 121 and the second roller 122. The compression adjustment unit 140 includes a driving member 141, a base 142, and a connecting arm 143. The driving member 141 and the base 142 are respectively connected to the bracket 110. The middle portion of the connecting arm 143 is hinged to the base 142. The two ends of the connecting arm 143 are respectively connected to the driving member 141 and the rotating shaft of the first roller 121. The driving member 141 can drive the connecting arm 143 to swing, thereby adjusting the position of the rotating shaft of the first roller 121, thereby achieving the purpose of adjusting the compression force between the first roller 121 and the second roller 122.

[0030] Optionally, the driving member 141 in the embodiment of the present application may include any one of a driving cylinder, a linear motor, a driving hydraulic cylinder and a driving motor.

[0031] The surface material of the first roller 121 is designed with a first adhesive layer 1210 with greater friction and a softer texture. When the base paper passes through the first roller 121 from left to right, it drives the first roller 121 to move clockwise. At the same time, the first roller 121 maintains a contact state with the second roller 122 below under the action of the driving member 141. Driven by the friction force of the first roller 121, the second roller 122 simultaneously moves in the opposite direction, that is, counterclockwise (if the base paper moves in the opposite direction, the roller moves in the opposite direction). The lower half of the second roller 122 is immersed in the water tank, so the water adheres to its surface.

[0032] Optionally, a liquid level control valve 131 can be installed within the water tank 130 to automatically replenish water to a specified location upon detecting a drop in the liquid level. Because the cross-section of the second roller 122, which is wet on its surface, faces the opposite direction from the first roller 121, pressure on the second roller 122 partially transfers the water to the upper surface of the first roller 121. This surface water then evenly permeates the base paper as it moves across the first roller 121, thus providing water to the paper web.

[0033] Optionally, see Figure 3 The water supply device 100 in the embodiment of the present application also includes a scraper 150 and a scraper adjustment unit 160. The scraper 150 is set corresponding to the outer surface of the second roller 122, and is used to control and adjust the amount of water on the outer surface of the second roller 122; the scraper adjustment unit 160 is connected to the bracket 110, and the scraper 150 is connected to the scraper adjustment unit 160. The scraper adjustment unit 160 can move relative to the bracket 110 and is used to control and adjust the distance between the scraper 150 and the outer surface of the second roller 122.

[0034] Water volume control is primarily achieved through the combined efforts of the pressure adjustment unit 140 and the scraper 150. For coarse adjustment, the pressure between the first and second rollers 121, 122 is controlled by the driver 141. This pressure controls the rotational speed of the second roller 122. Greater pressure results in faster rotation and greater water delivery, while lower pressure results in less water delivered. For fine adjustment, a scraper is positioned at the cross-section of the second roller 122. The pressure applied by the scraper controls the amount of water adhering to the surface of the second roller 122, thereby achieving precise control of water delivery.

[0035] The first roller 121 and the second roller 122 are in contact and move in opposite directions for a long time. In order to maintain the long-term stable operation of the equipment and reduce the uneven water supply caused by surface wear and deformation of the first roller 121 and the second roller 122 due to surface contact and extrusion, the first rubber layer 1210 on the surface of the first roller 121 is made of a relatively soft material, and the second rubber layer 1220 on the surface of the second roller 122 is made of a relatively hard material. Pressure compensation is achieved through plastic deformation of the first rubber layer 1210 on the surface of the first roller 121, thereby reducing the deformation of the first roller 121 and the second roller 122.

[0036] Please continue reading Figure 1 The drying device 200 is located behind the water supply device 100 and can include a drying box 210, a hot air system 220 (such as a hot air blower, an electric hot air blower, a gas bellows, etc.), an auxiliary bracket 230, etc. (within the comprehension of those skilled in the art and not further described here). To ensure sufficient water supply, excessive water supply is generally used in the water supply device 100. At the same time, to ensure that the water is evenly distributed on the surface of the base paper, the hot air blown out of the drying box 210 can help evenly distribute the water in the base paper and absorb the water through penetration, thereby improving the stress on the paper edge and thus achieving the effect of overcoming paper edge warping.

[0037] After the base paper is dried, the surface of the paper web will have a certain amount of heat. If the paper web is not cooled in time, the curled roll will experience a large-scale tension imbalance due to thermal expansion and contraction, resulting in loose finished rolls, uneven end surfaces, surface damage, and other problems, affecting subsequent sales and printing. Therefore, a cooling device 300 is added. The cooling device 300 can be composed of a cooling cylinder group, a cooling system, and auxiliary devices. Generally, to ensure that the base paper is cooled to room temperature after passing through the drying oven, multiple cooling cylinders are required to work simultaneously. A cooling medium (usually low-temperature oil or cooling water) flows through the cooling cylinders, and heat is exchanged with the base paper on the surface of the cooling cylinder to achieve cooling of the base paper. To ensure the low temperature of the cooling medium, the oil or water is generally continuously cooled by a cooler, and supporting pipelines, circuits, and equipment fixtures are also required.

[0038] The device for combating paper edge warping works as follows: Warping of the parent paper edge is primarily caused by uneven stress distribution within the paper web. During the papermaking and rewinding process, factors such as fiber orientation differences, drying gradients, and mechanical tension lead to residual stress differences in the transverse direction of the paper web. When these internal stresses are released, they cause edge curling. The water supply device achieves stress redistribution by precisely controlling water penetration. Its working principle can be divided into three stages:

[0039] First, the water supply is evenly distributed across the paper web's horizontal width. Water molecules penetrate the interfiber spaces, forming a lubricating layer and softening binding substances like hemicellulose. This reduces the hydrogen bonding strength between fibers by approximately 40%, creating the necessary conditions for stress release.

[0040] Secondly, water penetration triggers axial fiber expansion (a transverse expansion coefficient of approximately 1.5-2%). By regulating the depth of water penetration (typically controlled at 30-50% of the paper web thickness), the surface fibers undergo controllable expansion. This expansion force offsets the original compressive stress and induces micro-displacement reconstruction in the fibers, achieving stress field rebalancing.

[0041] Finally, a matching drying oven performs instantaneous surface drying (temperature controlled at 85-95°C), rapidly setting the surface fibers. At this point, the interior still maintains a moderate moisture content (8-12%). During the subsequent natural drying process, the fibers gradually reach equilibrium through a stress-relieving mechanism. This treatment reduces the transverse stress difference of the paper web from an initial 200-300 N / m to below 50 N / m, effectively eliminating edge warping. This process achieves dynamic adjustment of the fiber network structure through precise control of moisture gradients and thermal parameters, permanently eliminating residual stress.

[0042] The core of the design is how the water supply device ensures that the water is evenly, controllably and stably distributed on the banner surface of the paper.

[0043] The processing equipment for overcoming paper edge warping in the embodiments of the present application, through the design of a structure with a water supply device, a drying device, and a cooling device, can effectively solve the problem of paper edge warping, achieve a smooth and glossy cross-section of zero-plastic paper, reduce the problems of copyback and quality abnormalities, and solve the problems of a surge in scrap rate, increased energy consumption, packaging seal failure, printing deviation, reduced market trust, and increased carbon footprint caused by the curling of finished products in the zero-plastic paper production process. It basically solves the problems of a surge in scrap rate, increased energy consumption, packaging seal failure, printing deviation, reduced market trust, and increased carbon footprint caused by the curling of finished products in the zero-plastic paper production process. Currently, the amount of paper edge warping can be effectively reduced by approximately 80%, the stable operation time of the equipment is maintained at more than three months, and the qualified rate of finished products is increased by approximately 92%, achieving the purpose of overcoming paper edge warping for zero-plastic paper. At the same time, it greatly reduces the intensity of manual labor and has achieved good working results in actual production.

[0044] The above descriptions are only some embodiments of the present application and do not limit the scope of protection of the present application. Any equivalent device or equivalent process transformation made using the contents of the description and drawings of this application, or directly or indirectly applied in other related technical fields, are also included in the scope of patent protection of this application.

Claims

1. A processing device for overcoming paper edge warping, characterized in that: The processing equipment includes: a water supply device, a drying device and a cooling device arranged in sequence along the base paper flow line; the water supply device is used to provide moisture to the base paper, the drying device is used to dry the base paper after being soaked with water, and the cooling device is used to cool the dried base paper.

2. The processing equipment according to claim 1, characterized in that The water supply device includes a bracket, a roller and a water trough. The roller is rotatably connected to the bracket. The water trough is fixed to the bracket and is used to hold water. The roller is partially immersed in the water in the water trough. The raw paper to be processed passes through the roller and drives the roller to rotate, thereby transferring the water on the roller to the raw paper to be processed.

3. The processing equipment according to claim 2, characterized in that The roller includes a first roller and a second roller. The first roller and the second roller are arranged in parallel and rollingly attached. The first roller is used to contact the base paper to be processed and can rotate under the drive of the base paper. The second roller rotates under the drive of the first roller. The second roller is partially immersed in the water in the water tank.

4. The processing equipment according to claim 3, characterized in that A first adhesive layer is provided on the surface of the first roller, and the first adhesive layer is in rolling contact with the second roller.

5. The processing equipment according to claim 4, characterized in that A second rubber layer is provided on the surface of the second roller, and the second rubber layer is in rolling contact with the first rubber layer of the first roller; wherein the hardness of the first rubber layer is less than the hardness of the second rubber layer.

6. The processing equipment according to claim 3, characterized in that The water supply device further includes a compression adjustment unit, which is used to adjust the compression force between the first roller and the second roller.

7. The processing equipment according to claim 6, characterized in that The compression adjustment unit includes a driving member, a base and a connecting arm. The driving member and the base are respectively connected to the bracket. The middle part of the connecting arm is hinged to the base. The two ends of the connecting arm are respectively connected to the driving member and the rotating shaft of the first roller.

8. The processing equipment according to claim 7, characterized in that The driving component includes any one of a driving cylinder, a linear motor, a driving hydraulic cylinder and a driving motor.

9. The processing equipment according to claim 3, characterized in that The water supply device further includes a scraper, which is arranged corresponding to the outer surface of the second roller and is used to control and adjust the amount of water on the outer surface of the second roller.

10. The processing equipment according to claim 9, characterized in that The water supply device further includes a scraper adjustment unit, which is connected to the scraper and is used to control and adjust the distance between the scraper and the outer surface of the second roller.

Images