A forming paper machine with inclined wire

Abstract

This invention discloses a wire-forming papermaking apparatus, comprising a frame; a weir plate disposed on the frame and extending along a first direction to form a weir region; a forming wire that tilts upwards from the side near the weir plate to the side away from the weir plate to form a filtering forming region; and pulp guards that extend along the first direction from the weir region to the filtering forming region, with the pulp guards located on both sides of the first direction and positioned opposite each other in a second direction based on the first direction. During the process of conveying pulp from the front end of the weir region to the filtering forming region along the first direction, a portion of the pulp is conveyed along the first direction to the filtering forming region via the forming wire for filtering, while a portion of the pulp overflows over the top of at least one pulp guard and overflows along the second direction to outside the weir region or the filtering forming region, resulting in continuous dynamic flow and partial overflow outside the weir region or the filtering forming region during the conveying process. This invention can improve the forming quality of paper using conventional equipment.

Description

Technical Field

[0001] This invention relates to the field of inclined wire forming papermaking equipment, and in particular to an inclined wire forming papermaking device. Background Technology

[0002] Inclined wire formers are one of the commonly used wet forming equipment in the papermaking industry. Because their inclined wire surface can enhance gravity dewatering and make the fibers naturally oriented, they are particularly suitable for papermaking of long fibers, high basis weight and special filtration performance pulps. They occupy an important position in the production of specialty paper and high-performance fiber materials.

[0003] In actual production, it has been found that in the production of certain special papers (such as carbon fiber paper and glass fiber paper), the paper uniformity and physical strength properties of existing inclined wire forming paper machines do not meet the material requirements.

[0004] Chinese invention patent application CN202110468367.6 discloses a method for preparing carbon paper with a gradient pore structure. The method involves preparing carbon fibers with different aspect ratios into slurries, then sequentially laying them in a gradient manner according to their aspect ratio from high to low. The slurries are then formed using a skein-and-wire method to obtain a three-dimensional network structure carbon felt precursor. This precursor is then impregnated in a resin solution and subjected to hot pressing, carbonization, and graphitization to obtain the carbon paper. This method creates interconnected pores within the prepared carbon paper, with the pore size varying gradient along the thickness direction, which improves gas transport efficiency and effectively enhances the mass and heat transfer properties of the carbon paper. The carbon paper prepared by this method has the advantages of uniform thickness and pore structure, improving the tensile strength and reducing the resistivity of the paper.

[0005] Chinese invention patent application number CN201910369140.9 discloses a method for preparing basalt fiber paper. The method involves pretreating the basalt fiber slurry with alkali and acid treatments sequentially to improve fiber dispersibility. Then, a mixed dispersant of sodium hexametaphosphate and polyethylene oxide, along with organic binders such as sodium carboxymethyl cellulose and inorganic binders such as water glass, are added to enhance the inter-fiber bonding strength. This combined process significantly improves fiber uniformity and paper strength.

[0006] Chinese invention patent application number CN201320302888.5 discloses a structure for an inclined mesh forming device. The inclined mesh headbox is equipped with a multi-cavity square cone tube that is seamlessly connected to an orifice plate to achieve horizontal isobaric stratified slurry feeding. The forming box is composed of three parts and is equipped with a white water outlet and a flow guide baffle to adjust the dewatering rate in different zones. The stepped diffuser hole design of the orifice plate enhances turbulence and promotes uniform fiber distribution.

[0007] One method for preparing gradient-pore carbon paper optimizes the internal pore structure of the carbon paper by gradient-laying carbon fibers with different aspect ratios, improving thickness uniformity, tensile strength, and electrical conductivity, starting from the perspective of pulp ratio and layup process. Another method for preparing basalt fiber paper improves the dispersion uniformity and interfiber bonding force of basalt fibers by combining surface treatment agents, dispersants, and adhesives, thereby improving paper strength. A method for preparing inclined wire forming device achieves isobaric stratified pulp feeding and zoned dewatering through a multi-cavity square cone tube and perforated plate stepped diffusion design, thereby enhancing turbulence and promoting uniform fiber distribution. However, in actual production, it has been found that improvements in pulp ratio, additives, and equipment structure, when making paper from certain special materials, still fail to meet the requirements for paper uniformity and physical strength properties, resulting in persistent forming defects.

[0008] Therefore, it is urgent to research and develop a slanted wire forming papermaking equipment to solve the above-mentioned technical defects. Summary of the Invention

[0009] The purpose of this invention is to provide a wire mesh forming papermaking device that can improve the forming quality of paper using traditional equipment.

[0010] To achieve the above objectives, the present invention provides a slanted wire forming papermaking device, the specific implementation of which is as follows: A wire mesh forming papermaking device, including a frame; A weir plate, disposed on the frame, extends along a first direction to form a weir area, used to receive slurry and transport slurry along the first direction; The forming inclined mesh, tilted upwards from the side closer to the weir plate towards the side farther from the weir plate, forms a filtration and forming area for receiving slurry and filtering it; and The slurry guardrail extends from the weir flow area to the filtration and forming area along a first direction. The slurry guardrail is located on both sides of the first direction and is set opposite to each other in a second direction with the first direction as a reference. During the process of conveying the slurry from the front end of the weir flow area to the filter forming area along the first direction, part of the slurry is conveyed along the first direction to the filter forming area to the forming inclined mesh filter forming, and part of the slurry overflows the top of at least one side of the slurry guardrail and overflows along the second direction to the outside of the weir flow area or the filter forming area, so that the slurry continues to flow dynamically during the conveying process and partially overflows to the outside of the weir flow area or the filter forming area.

[0011] This invention provides a tilted wire forming papermaking device. Compared to existing technologies, by extending the pulp guard along a first direction from the weir flow area to the filtration forming area, during the process of conveying the pulp from the front end of the weir flow area to the filtration forming area, part of the pulp is continuously conveyed along the first direction to the tilted wire forming filtration forming, while part of the pulp overflows over the top of at least one side of the pulp guard and overflows along a second direction to outside the weir flow area or the filtration forming area. This ensures that the pulp continuously and dynamically flows during the conveying process and partially overflows outside the weir flow area or the filtration forming area. Even when the pulp supply rate is greater than the filtration rate of the filtration forming area, the excess pulp... The pulp will not remain on the forming slope for a long time, but can be continuously and dynamically discharged along the second direction, so that the pulp is always in a state of flow and renewal. It will not cause fiber flocculation and sedimentation due to pulp retention, thus solving the problem of forming defects such as clumps and spots in paper web forming caused by fiber flocculation and sedimentation due to pulp retention. It improves the uniformity and physical strength of paper web forming. Moreover, it can be used in traditional inclined wire forming equipment simply by adding a pulp guard structure and allowing the pulp to overflow from the top of the pulp guard along the second direction. It has the advantages of simple structure and low cost.

[0012] In some of these embodiments, The thickness direction of the slurry accumulated in the weir flow area or the filtration forming area is the first... Three directions The height of the slurry guardrail is adjustable in the third direction.

[0013] By making the height of the slurry guardrail adjustable in the third direction, flexible control of the overflow level threshold is achieved. The optimal overflow height can be matched according to the dewatering characteristics and process parameters of different slurries, thereby improving the equipment's adaptability to different slurry formulations and the flexibility of process adjustment.

[0014] In some embodiments, the slurry guardrail includes a plurality of first plates that are stacked sequentially in a third-order upward direction.

[0015] By setting the slurry guardrail to include several first plates and stacking these first plates sequentially in a third-order upward direction, the modular adjustment of the guardrail height is achieved. The overflow height can be changed simply by increasing or decreasing the number of stacked first plates. The structure is simple and easy to adjust, reducing the complexity of height adjustment and manufacturing costs.

[0016] In some embodiments, a seal is provided between two adjacent first plates, and the seal is sealed to the first plate.

[0017] By setting a seal between two adjacent first plates and sealing the seal with the first plate, leakage of slurry from the gaps between the plates is prevented, ensuring the overall sealing of the slurry guardrail during height adjustment and preventing unexpected slurry loss.

[0018] In some embodiments, the slurry guardrail includes a fixed baffle and a movable baffle, the fixed baffle and the movable baffle being staggered in a second direction, and the movable baffle being movable relative to the fixed baffle in a third direction.

[0019] By configuring the slurry guardrail to include a fixed baffle and a movable baffle, and staggering the fixed baffle and the movable baffle in a second direction, with the movable baffle moving relative to the fixed baffle in a third direction, stepless adjustment of the guardrail height is achieved. This enables fine adjustment of the overflow height, improves the accuracy and continuity of height adjustment, and enhances the equipment's adaptability to different working conditions.

[0020] In some embodiments, the slurry guardrail is a detachable second plate, and the height of the slurry guardrail in the second direction is adjusted by replacing the second plate.

[0021] By setting the slurry guardrail as a detachable second plate and adjusting the height of the slurry guardrail in the second direction by replacing the second plate, the height of the guardrail can be quickly changed. Different process requirements can be adapted simply by disassembling and replacing the second plate of different specifications. The structure is simple, easy to maintain, and reduces equipment maintenance and replacement costs.

[0022] Based on the above technical solution, the present invention has the following beneficial effects compared with the prior art: By extending the slurry guardrail from the weir flow area to the filtration molding area along a first direction, during the process of conveying the slurry from the front end of the weir flow area to the filtration molding area, part of the slurry is continuously conveyed along the first direction to the molding inclined mesh filtration molding, while part of the slurry overflows over the top of at least one side of the slurry guardrail along a second direction to outside the weir flow area or the filtration molding area. This ensures that the slurry continuously flows dynamically during the conveying process and partially overflows outside the weir flow area or the filtration molding area. Even if the slurry supply rate is greater than the filtration rate of the filtration molding area, the excess slurry will not remain on the molding inclined surface for an extended period. Instead of being retained, the pulp can be continuously and dynamically discharged along the second direction, keeping the pulp in a state of constant flow and renewal. This prevents fiber flocculation and sedimentation caused by pulp retention, thus solving the problem of forming defects such as clumps and spots in paper web forming caused by fiber flocculation and sedimentation due to pulp retention. This improves the uniformity and physical strength of paper web forming. Moreover, it can be used in traditional inclined wire forming equipment simply by adding a pulp guard structure and allowing the pulp to overflow from the top of the pulp guard along the second direction. It has the advantages of simple structure and low cost. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a structural schematic diagram from another perspective of the present invention; Figure 3 This is a cross-sectional view of the present invention.

[0024] Explanation of reference numerals in the attached figures: 100. Frame; 110. Weir area; 111. Weir plate; 120. Filter forming area; 121. Forming inclined mesh; 130. Slurry guardrail; 131. First plate; 140. Receiving space. Detailed Implementation

[0025] To facilitate understanding of the present invention, specific embodiments of the present invention will be described in more detail below with reference to the accompanying drawings.

[0026] Unless otherwise specified or defined, the terms "first," "second," etc., used in this document are for distinguishing names only and do not represent a specific number or order.

[0027] Unless otherwise stated or defined, the term “and / or” as used herein includes any and all combinations of one or more of the related listed items.

[0028] It should be noted that in this article, "fixed to" or "connected to" can mean directly fixed to or connected to a component, or indirectly fixed to or connected to a component.

[0029] like Figure 1-3 As shown, this embodiment provides a slanted wire forming papermaking device, including a frame 100, on which a weir plate 111 is provided. The weir plate 111 extends along a first direction to form a weir region 110. The weir region 110 is used to receive pulp and transport pulp along the first direction.

[0030] Understandably, the slurry being carried is a slurry that has been prepared and distributed to be used for filter molding.

[0031] It also includes a forming inclined mesh 121, which slopes upwards from the side of the connecting weir plate 111 toward the side away from the weir plate 111 to form a water-filtering forming area 120, used to receive slurry and filter it. In actual use, the water-filtering forming of the slurry on the forming inclined mesh 121 is achieved by using a vacuum component or natural water filtration.

[0032] It also includes a slurry guardrail 130, which extends from the weir flow area 110 to the filtration and forming area 120 along a first direction. The slurry guardrail 130 is located on both sides of the first direction and is arranged opposite to each other in a second direction with the first direction as a reference. In actual use, the relative arrangement of the slurry guardrail 130 in the second direction with the first direction as a reference can be symmetrical or staggered.

[0033] During the process of conveying the pulp from the front end of the weir region 110 to the filter forming region 120 along the first direction, part of the pulp is conveyed into the filter forming region 120 along the first direction, and part of the pulp overflows the top of at least one pulp guardrail 130 and overflows into the weir region 110 or the filter forming region 120 along the second direction. This ensures that the pulp is continuously and dynamically flowing during the conveying process, with some overflowing into the weir region 110 or the filter forming region 120. This keeps the pulp in a state of constant flow and renewal, preventing fiber flocculation and sedimentation due to pulp retention, thus solving the problem of forming defects such as clumps and spots in paper web forming caused by fiber flocculation and sedimentation due to pulp retention. It can be used with traditional inclined wire forming equipment simply by adding a pulp guardrail structure and allowing the pulp to overflow from the top of the pulp guardrail along the second direction. Compared with existing technologies, it achieves uniformity and physical strength in paper web forming while ensuring controllable production capacity and cost.

[0034] Understandably, since the slurry guardrail 130 extends from the weir flow area 110 to the filtration and forming area 120 along the first direction, the slurry can overflow and be discharged through the top of the slurry guardrail 130 throughout the entire process of the slurry entering the filtration and forming area 120 from the weir flow area 110 and running upward along the forming slope 121.

[0035] Specifically, this means that whether in the filtration and forming area 120, the weir flow area 110, or the junction of the weir flow area 110 and the filtration and forming area 120, when the slurry accumulates on the forming slope 121 due to insufficient filtration, the slurry can be discharged through overflow. When the feeding speed increases instantaneously, causing the liquid level to rise, the slurry can also be discharged in time through overflow, ensuring that there will be no abnormal slurry retention along the entire conveying path, which would lead to fiber flocculation and sedimentation.

[0036] The slurry accumulates in the weir flow area 110 or the filtration and forming area 120 in a third-dimensional direction. The height of the slurry guardrail 130 in this third-dimensional direction is adjustable, enabling flexible control of the slurry overflow level threshold. This allows for matching the optimal overflow height based on the dewatering characteristics and process parameters of different slurries, improving the equipment's adaptability to different slurry formulations and the flexibility of process adjustment. Weir flow area 110 or The deeper the filtration molding zone 120 is in the third direction, the thicker the slurry will be.

[0037] Optionally, the slurry guardrail 130 includes a plurality of first plates 131, which are stacked sequentially in the third direction. In actual use, the height of the slurry guardrail 130 in the third direction can be changed by increasing or decreasing the number of stacked first plates 131, thereby changing the overflow height of the slurry. It has the advantages of simple structure and convenient adjustment.

[0038] Furthermore, a sealing element is provided between two adjacent first plates 131. The sealing element is sealed to the first plate 131 to prevent the slurry from leaking from the gap between the plates, ensuring the overall sealing of the slurry guardrail 130 during the height adjustment process and preventing unexpected slurry loss.

[0039] In practical use, the sealant uses corrosion-resistant and high-temperature-resistant sealant from the prior art.

[0040] Optionally, the slurry guardrail 130 includes a fixed baffle and a movable baffle, which are staggered in a second direction, and the movable baffle moves relative to the fixed baffle in a third direction. The relative movement between the fixed and movable baffles allows for stepless height adjustment of the slurry guardrail 130 in the third direction, enabling fine adjustment of the overflow height, improving the accuracy and continuity of height adjustment, and enhancing the equipment's adaptability to different working conditions.

[0041] Specifically, the fixed baffle is fixed to the frame 100, and its upper edge remains unchanged in a third-direction position. The movable baffle is disposed inside or outside the fixed baffle and can move up and down relative to the fixed baffle in a third-direction. When the upper edge of the movable baffle is higher than the upper edge of the fixed baffle, the effective overflow height of the slurry guardrail 130 is determined by the upper edge of the movable baffle; when the upper edge of the movable baffle is lower than the upper edge of the fixed baffle, the effective overflow height of the slurry guardrail 130 is determined by the upper edge of the fixed baffle. By adjusting the position of the movable baffle, the overall effective height of the slurry guardrail 130 can be changed, thereby achieving stepless adjustment of the overflow level threshold.

[0042] Specifically, the bottom of the movable baffle can be screwed to the frame 100 by a screw. The relative position between the movable baffle and the fixed baffle can be adjusted by adjusting the height of the screw in the third direction. Of course, other existing structures such as guide rail sliders can also be used to realize the relative movement of the movable baffle and the fixed baffle, which will not be described in detail here.

[0043] Optionally, the slurry guardrail 130 is a detachable second plate. The height of the slurry guardrail 130 in the third direction can be adjusted by replacing the second plate. In actual use, different process requirements can be adapted by disassembling and replacing the second plate of different specifications. The structure is simple and easy to maintain, which reduces the equipment maintenance and replacement costs.

[0044] In this embodiment, the first direction is the direction between the weir flow area 110 and the filtration and forming area 120, the second direction is the direction in which the slurry guardrail 130 is set relative to the first direction, and the third direction is the direction from the bottom to the top of the weir flow area 110, i.e., the depth direction.

[0045] In this embodiment, a receiving space 140 can be provided on the frame 100. The slurry overflowing from the top of the slurry guardrail 130 along the second direction enters the receiving space 140 for collection or is transferred to an external collection container for subsequent slurry recycling.

[0046] In practical use, the height of the pulp guardrail 130 in the third direction can be adjusted according to the dewatering characteristics and process parameters of the pulp to control the liquid level threshold for overflow and adapt to the paper forming needs of different materials.

[0047] When controlling the overflow level threshold by adjusting the height of the slurry guardrail 130, the adjustment steps include at least one of the following three methods, depending on the specific structure used: Firstly, when the slurry guardrail 130 includes a plurality of overlapping first plates 131, the overall height of the slurry guardrail 130 can be changed by increasing or decreasing the number of first plates 131, thereby achieving modular step adjustment. Secondly, when the slurry guardrail 130 includes a fixed baffle and a movable baffle that is offset from the fixed baffle, the relative position of the movable baffle and the fixed baffle can be changed by moving the movable baffle along a third direction, thereby achieving stepless fine adjustment of the height. Third, when the slurry guardrail 130 includes a second plate that is detachably connected to the frame 100, the height can be quickly adjusted by disassembling the current second plate and replacing it with a second plate of a different specification.

[0048] The above three adjustment methods can be used individually or in combination according to actual production needs, in order to adapt to the dewatering characteristics of different pulps and the process requirements of different paper types, thereby improving the versatility of the equipment and production flexibility.

[0049] In this embodiment, the height adjustment of the slurry guardrail 130 in the third-party direction can also be achieved using other existing structures, not limited to the three methods described in this embodiment. Any structure that can achieve the height adjustment of the slurry guardrail 130 in the third-party direction is acceptable.

[0050] It is important to note that a deeply ingrained technical perception has long existed in this field: during the operation of inclined wire mesh forming equipment, the slurry overflowing the guardrails on both sides of the forming mesh 122 is considered a major process accident resulting in fiber loss and increased wastewater load, a state of process out of control that must be strictly avoided. Based on this perception, "preventing the slurry from overflowing the guardrails" is regarded as the core principle of inclined wire mesh forming process control. Any solution that might cause slurry overflow is considered a process regression and is not technically acceptable by those skilled in the art.

[0051] For example, in a non-contact sealing device for a wire forming machine disclosed in application number 201910304155.7, the sealing structures between the left side of the headbox and the wire section, the right side of the headbox and the wire section, and the lower lip plate of the headbox and the wire section are described. If the seal is not good, the pulp will spray out from the corresponding part of the headbox. Therefore, these sealing structures play a crucial role in the normal production of the wire forming machine and the paper surface quality. Similarly, in a slurry-blocking device for use with an insulating paperboard machine disclosed in application number 200920239950.4, the slurry-blocking plate can block the pulp when it is evenly sprayed onto the forming wire 122 and transported, preventing the pulp from flowing to both sides of the forming wire 122 and causing uneven pulp thickness. A water spraying device sprays water into the gap between the slurry-blocking plate and the forming wire 122, ensuring the straightness of the formed paper edge and preventing the slurry-blocking plate from scratching the edge of the formed paper and affecting the papermaking quality.

[0052] Therefore, it is evident that blocking the overflow of pulp in the filtration and forming area 120 by using the pulp guardrail 130 is a necessary technical means to prevent major process accidents such as fiber loss and increased wastewater load. Those skilled in the art would not realize that the paper web forming defects caused by fiber flocculation and sedimentation are due to the height of the guardrail blocking the overflow of pulp.

[0053] The inclined wire forming papermaking equipment provided in this embodiment, compared with the prior art, extends the pulp guardrail 130 from the weir region 110 to the filter forming region 120 along a first direction. During the process of conveying the pulp from the front end of the weir region 110 to the filter forming region 120, part of the pulp is continuously conveyed along the first direction to the forming inclined wire 121 for filter forming, and part of the pulp overflows over the top of at least one side of the pulp guardrail 130 and overflows along the second direction to outside the weir region 110 or the filter forming region 120. This allows the pulp to continuously and dynamically flow during the conveying process and partially overflow to outside the weir region 110 or the filter forming region 120, even if the pulp supply rate is greater than that of the filter forming region 110. At a filtration speed of 20, excess pulp will not remain on the forming inclined surface 121 for a long time, but can be continuously and dynamically discharged along the second direction. This ensures that the pulp is always in a state of flow and renewal, and will not cause fiber flocculation and sedimentation due to pulp retention. This solves the problem of forming defects such as clumps and spots in paper web forming caused by fiber flocculation and sedimentation due to pulp retention, and improves the uniformity and physical strength of paper web forming. Moreover, it can be used in traditional inclined wire forming equipment simply by adding a pulp guard 130 structure to the traditional inclined wire forming equipment and allowing the pulp to overflow from the top of the pulp guard 130 along the second direction. It has the advantages of simple structure and low cost.

[0054] Based on the disclosure and teachings of the foregoing specification, those skilled in the art can make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the protection scope of the claims of the present invention. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on the present invention.

Claims

1. A type of inclined wire forming papermaking equipment, characterized in that, include Rack (100); A weir plate (111) is provided on the frame (100) and extends along the first direction to form a weir area (110) for receiving slurry and conveying slurry along the first direction; The forming inclined mesh (121) slopes upward from the side connected to the weir plate (111) towards the side away from the weir plate (111), forming a water-filtering forming area (120) for receiving slurry and filtering it; and Slurry guardrail (130) extends from the weir flow area (110) to the filter forming area (120) along a first direction. The slurry guardrail (130) is located on both sides of the first direction and is set opposite to each other in a second direction with the first direction as a reference. During the process of conveying the slurry from the front end of the weir flow area (110) to the filter forming area (120) along the first direction, part of the slurry is conveyed along the first direction to the filter forming area (120) to the forming inclined net (121) for filter forming, and part of the slurry overflows the top of at least one side of the slurry guardrail (130) and overflows along the second direction to the outside of the weir flow area (110) or the filter forming area (120), so that the slurry continues to flow dynamically during the conveying process and part of it overflows to the outside of the weir flow area (110) or the filter forming area (120).

2. The inclined wire forming papermaking equipment as described in claim 1, characterized in that, The thickness of the slurry accumulated in the weir flow area (110) or the filter forming area (120) is in the third direction, and the height of the slurry guardrail (130) in the third direction is adjustable.

3. The inclined wire forming papermaking equipment as described in claim 2, characterized in that, The slurry guardrail (130) includes a plurality of first plates (131), which are stacked sequentially in a third direction.

4. The inclined wire forming papermaking equipment as described in claim 3, characterized in that, A sealing element is provided between two adjacent first plates (131), and the sealing element is sealed to the first plate (131).

5. The inclined wire forming papermaking equipment as described in claim 2, characterized in that, The slurry guardrail (130) includes a fixed baffle and a movable baffle, which are staggered in a second direction, and the movable baffle moves relative to the fixed baffle in a third direction.

6. The inclined wire forming papermaking equipment as described in claim 2, characterized in that, The slurry guardrail (130) is a detachable second plate, and the height of the slurry guardrail (130) in the third direction can be adjusted by replacing the second plate.

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