Papermaking system for low-basis-weight paper

Abstract

The utility model discloses a low-basis-weight paper type papermaking system which comprises a surface layer headbox, a surface layer forming net, a bottom layer forming net, a paper tape composite part, a squeezing dehydration part and a post-processing assembly, and the surface layer forming net and the bottom layer forming net are arranged in the front-back direction and distributed at intervals in the up-down direction. The paper tape composite part, the squeezing dewatering part and the post-processing assembly are sequentially arranged behind the position between the surface layer forming net and the bottom layer forming net in the front-back direction, and the surface layer headbox is arranged in front of the surface layer forming net and used for supplying paper pulp to the surface layer forming net and the bottom layer forming net. The surface layer forming net and the bottom layer forming net are used for manufacturing paper tapes respectively, the paper tape composite part is used for compositing the two paper tapes into a paper tape composite body, the squeezing and dewatering part is used for squeezing and dewatering the paper tape composite body, and the post-processing assembly is used for sizing, drying and calendaring the squeezed and dewatered paper tape composite body. And efficient production of low-basis-weight paper types can be realized.

Description

Technical Field

[0001] The utility model belongs to the field of papermaking equipment, in particular to a papermaking system for low-weight paper grades. Background Art

[0002] Low weight paper, also known as LWC paper, has excellent printing performance. However, most of the existing low weight paper is single-layer paper tape, and the existing low weight paper machines run at a slow speed. The main reason for its slow running speed is that if the paper tape runs too fast, it will lead to low dehydration efficiency and uneven dehydration (low dehydration rate and uneven dehydration will inevitably lead to low strength of the paper tape, which is easy to break, so it is not easy to produce at high speed). Utility Model Content

[0003] In order to solve the above technical problems, the purpose of the utility model is to provide a low-weight paper grade papermaking machine with good drying effect and high papermaking efficiency.

[0004] In order to achieve the above-mentioned purpose, the technical scheme of the utility model is as follows: a low-weight paper grade papermaking system, including a surface layer flow box, a surface layer forming net, a bottom layer forming net, a paper tape composite, a pressing and dehydrating component and a post-processing assembly, the surface layer forming net and the bottom layer forming net are both arranged along the front-to-back direction and spaced apart along the up-and-down direction, the paper tape composite, the pressing and dehydrating component and the post-processing assembly are sequentially arranged behind the surface layer forming net and the bottom layer forming net along the front-to-back direction, the surface layer flow box is arranged in front of the surface layer forming net, the surface layer flow box is used to supply pulp to the surface layer forming net and the bottom layer forming net, the surface layer forming net and the bottom layer forming net are used to make paper tapes respectively, the paper tape composite is used to composite two of the paper tapes into a paper tape composite, the pressing and dehydrating component is used to press and dehydrate the paper tape composite, and the post-processing assembly is used to apply glue, dry and calender the pressed and dehydrated paper tape composite.

[0005] The beneficial effect of the above technical solution is that the surface layer flow box can supply pulp to the surface layer forming net and the bottom layer forming net respectively, and the surface layer forming net and the bottom layer forming net respectively process the pulp into two paper tapes distributed up and down, and the two paper tapes are compounded into a paper tape composite by a paper tape composite component, and the pressing and dewatering component dehydrates the paper tape composite so that the paper tape composite can be quickly transported on the entire production line, and the post-processing assembly performs subsequent gluing, drying and calendering treatments on the paper tape composite to obtain a finished paper tape.

[0006] In the above technical solution, two surface layer headboxes are provided, and the two surface layer headboxes are respectively provided corresponding to the surface layer forming net and the bottom layer forming net, and the surface layer forming net and the bottom layer forming net are used to respectively receive the pulp sent from the corresponding surface layer headboxes.

[0007] The beneficial effect of the above technical solution is that the two surface layer headboxes can operate independently without interfering with each other, which is beneficial to improving the operating efficiency of the surface layer forming wire and the bottom layer forming wire.

[0008] The above technical solution also includes a vacuum dewatering box and a vacuum pumping component. The vacuum dewatering box is horizontally arranged, and the front end of the vacuum dewatering box has two pulp feeding inlets spaced apart from each other up and down, and the rear end of the vacuum dewatering box has a paper tape outlet. The vacuum dewatering box has a negative pressure interface, and the air inlet of the vacuum pumping component is connected to the negative pressure interface. The surface layer forming net, the bottom layer forming net and the paper tape composite are all arranged in the vacuum dewatering box, and the two pulp feeding inlets correspond to the two surface layer flow boxes one by one, and each surface layer flow box feeds pulp into the vacuum dewatering box through the corresponding pulp feeding inlet.

[0009] The beneficial effect of the above technical solution is that negative pressure drying can be performed during the paper tape forming and compounding stage, which can further reduce the moisture in the paper tape, thereby further improving the strength of the paper tape during the forming and compounding stage, thereby achieving high-speed production and high-speed transportation of the paper tape.

[0010] The vacuum pump described in the above technical solution is a vacuum pump, and the lower end of the vacuum dehydration box protrudes downward in a conical shape, and a drain outlet is provided at the lowest horizontal point, and a drain valve is provided at the drain outlet.

[0011] The beneficial effects of the above technical solution are: its structure is simple and the pre-dehydration effect of the paper tape and the paper tape composite is good.

[0012] The vacuum pumping component described in the above technical solution is a gas-liquid separation device of a high vacuum system.

[0013] The beneficial effect of the above technical solution is that it can increase the negative pressure in the vacuum dehydration box and dehumidify the vacuum dehydration box.

[0014] In the above technical solution, a plurality of the pressing and dehydrating components are provided, and the plurality of the pressing and dehydrating components are arranged at intervals along the front-to-back direction between the paper tape composite component and the post-processing assembly.

[0015] The beneficial effect of the above technical solution is that the paper tape composite body can be dehydrated in multiple stages, so the dehydration effect is better.

[0016] The pressing and dehydrating component in the above technical solution is a pressing and dehydrating roller group.

[0017] The beneficial effect of the above technical solution is that it has a good dehydration effect.

[0018] In the above technical solution, two pressing and dehydrating components are provided.

[0019] The beneficial effect of the above technical solution is that it has a good dehydration effect and does not affect the high-speed transportation of the paper tape composite.

[0020] The post-processing assembly described in the above technical scheme includes a front-drying part, a gluing part, a post-drying part and a calendering part which are arranged in sequence along the front-to-back direction. The front-drying part is used to dry the paper-tape composite, the gluing part is used to apply glue to the surface of the dried paper-tape composite, the post-drying part is used to dry the glued paper-tape composite again, and the calendering part is used to calender the surface of the glued and dried paper-tape composite.

[0021] The beneficial effect of the above technical solution is that by drying the paper tape composite before and after gluing, the moisture content in the paper tape after the glue is solidified is avoided, and the calendering part can improve the brightness of the surface of the paper tape composite.

[0022] The post-processing assembly in the above technical solution also includes a paper roll, which is used to roll the paper tape composite after calendering.

[0023] The beneficial effect of the above technical solution is that the paper tape composite can be rolled into a tube after calendering. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the paper material flow in the low-weight paper grade papermaking system according to the embodiment of the utility model;

[0025] Figure 2 It is a structural schematic diagram of the vacuum dehydration box described in the embodiment of the utility model;

[0026] Figure 3 Another schematic diagram of the structure of the vacuum dehydration box in the embodiment of the utility model;

[0027] Figure 4 It is a schematic diagram of the specific structure of the low-weight paper grade papermaking system described in the embodiment of the utility model.

[0028] In the figure: 1 surface layer headbox; 2a surface layer forming net; 2b bottom layer forming net; 3 paper tape composite part; 4 pressing and dehydrating part; 5 post-processing assembly; 51 front drying part; 52 sizing part; 53 post-drying part; 55 calendering part; 55 paper winding part; 6 vacuum dehydration box; 61 pulp feeding inlet; 62 paper tape outlet; 63 negative pressure interface; 64 drain outlet; 65 drain valve; 7 vacuum pumping part; 8a paper tape; 8b paper tape composite. DETAILED DESCRIPTION

[0029] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention. The present invention is described in more detail in the following paragraphs by way of example with reference to the accompanying drawings. According to the following description and claims, the advantages and features of the present invention will be more clearly described. It should be noted that the drawings are all in a very simplified form and are not in precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention.

[0030] like Figure 1 As shown, this embodiment provides a low-weight paper grade papermaking system, including a surface layer flow box 1, a surface layer forming wire 2a, a bottom layer forming wire 2b, a paper tape composite 3, a pressing and dewatering component 4 and a post-processing assembly 5, wherein the surface layer forming wire 2a and the bottom layer forming wire 2b are arranged along the front-to-back direction and spaced apart along the up-down direction, the paper tape composite 3, the pressing and dewatering component 4 and the post-processing assembly 5 are sequentially arranged behind the surface layer forming wire 2a and the bottom layer forming wire 2b along the front-to-back direction, the surface layer flow box 1 is arranged in front of the surface layer forming wire 2a, the surface layer flow box 1 is used to supply pulp to the surface layer forming wire 2a and the bottom layer forming wire 2b, the surface layer forming wire 2a and the bottom layer forming wire 2b are used to make paper tapes 8a respectively, and the The paper tape composite part 3 is used to composite the two paper tapes 8a into a paper tape composite body 8b, the pressing and dehydrating part 4 is used to press and dehydrate the paper tape composite body 8b, and the post-processing assembly 5 is used to glue, dry and calender the paper tape composite body 8b after being pressed and dehydrated, so that the surface layer flow box can supply pulp to the surface layer forming net and the bottom layer forming net respectively, and the surface layer forming net and the bottom layer forming net respectively process the pulp into two paper tapes distributed up and down, and the two paper tapes are composited into a paper tape composite body by the paper tape composite part, the pressing and dehydrating part dehydrates the paper tape composite body so that the paper tape composite body can be quickly transported on the entire production line, and the post-processing assembly performs subsequent gluing, drying and calendering treatments on the paper tape composite body to obtain a finished paper tape.

[0031] In the above technical solution, two surface layer headboxes 1 are provided, and the two surface layer headboxes 1 are respectively provided corresponding to the surface layer forming net 2a and the bottom layer forming net 2b. The surface layer forming net 2a and the bottom layer forming net 2b are used to respectively receive the pulp sent by the corresponding surface layer headbox 1, so that the two surface layer headboxes can operate independently without interfering with each other, which is beneficial to improving the operation efficiency of the surface layer forming net and the bottom layer forming net.

[0032] like Figure 2As shown, the above technical scheme also includes a vacuum dewatering box 6 and a vacuum pumping member 7, the vacuum dewatering box 6 is horizontally arranged, the front end of the vacuum dewatering box 6 is provided with two pulp feeding ports 61 spaced apart from each other, the rear end of the vacuum dewatering box 6 is provided with a paper tape outlet 62, the vacuum dewatering box 6 is provided with a negative pressure interface 63, the air inlet of the vacuum pumping member 7 is communicated with the negative pressure interface 63, the surface layer forming net 2a, the bottom layer forming net 2b and the paper tape composite member 3 are all arranged in the vacuum dewatering box 6, the two pulp feeding ports 61 correspond to the two surface layer headboxes 1 one by one, each surface layer headbox 1 feeds pulp into the vacuum dewatering box 6 through the corresponding pulp feeding port 61, so that negative pressure drying can be performed in the paper tape forming and compounding stage, which can further reduce the moisture in the paper tape, thereby further improving the strength of the paper tape in the forming and compounding stage, thereby realizing high-speed production and high-speed transportation of the paper tape.

[0033] like Figure 3 As shown, the vacuum pump 7 in the above technical solution is a vacuum pump, and the lower end of the vacuum dehydration box 6 protrudes downward in a conical shape, and a drain port 64 is provided at the lowest level thereof, and a drain valve 65 is provided at the drain port 64, which has a simple structure and makes the pre-dehydration effect of the paper tape and the paper tape composite body good, or as Figure 3 As shown, the vacuum pump 7 is a high vacuum system gas-liquid separation device (such as the high vacuum system gas-liquid separation device disclosed in document number CN105107273B "High Vacuum System Gas-Liquid Separation Device"), which can increase the negative pressure in the vacuum dehydration box and dehumidify the vacuum dehydration box.

[0034] like Figure 4 As shown, in the above technical solution, a plurality of pressing and dehydrating components 4 are provided, and the plurality of pressing and dehydrating components 4 are arranged at intervals along the front-to-back direction between the paper tape composite component 3 and the post-processing assembly 5, so that the paper tape composite body can be dehydrated in multiple stages, so the dehydration effect is better.

[0035] The squeezing and dehydrating element 4 in the above technical solution is a squeezing and dehydrating roller group, which has a good dehydrating effect.

[0036] In the above technical solution, two pressing and dehydrating components 4 are provided, so that the dehydration effect is good and the high-speed transportation of the paper tape composite is not affected.

[0037] The post-processing assembly 5 in the above technical scheme includes a front baking component 51, a gluing component 52, a rear baking component 53 and a calendering component 54 which are arranged in sequence along the front-to-back direction. The front baking component 51 is used to dry the paper tape composite 8b, the gluing component 52 is used to apply glue to the surface of the dried paper tape composite 8b, the rear baking component 53 is used to dry the glued paper tape composite 8b again, and the calendering component 54 is used to calender the surface of the glued and dried paper tape composite 8b. By drying the paper tape composite before and after gluing, the moisture content in the paper tape after the glue is solidified can be avoided, and the calendering component can increase the brightness of the surface of the paper tape composite.

[0038] The post-processing assembly 5 in the above technical solution also includes a paper roll 55, and the paper roll 55 is used to roll up the paper tape composite 8b after calendering, so that the paper tape composite can be rolled into a roll after calendering.

[0039] In this embodiment, by providing a vacuum dehydration box, the moisture content of the paper strip after compounding can be reduced by 2% compared with the case where no vacuum dehydration box is provided. For the low-weight paper web, the strength of the wet paper sheet will increase by about 5% for every 1% decrease in its moisture content. As the strength of the paper strip increases, the operating speed of the entire low-weight paper papermaking system can be increased accordingly, and the probability of paper breaks can be reduced.

[0040] In this embodiment, the surface layer flow box 1, the surface layer forming mesh 2a, the bottom layer forming mesh 2b, the paper tape composite part 3, the pressing and dehydrating part 4, the front drying part 51, the sizing part 52, the rear drying part 53, the calendering part 54 and the paper winding part 55 all belong to the prior art and will not be described in detail here.

[0041] The paper tape production rate of the low-weight paper grade papermaking system provided in this embodiment can reach 1000m / min, while the average paper tape production rate before the improvement was 700-800m / min.

[0042] The above description is only a preferred embodiment of the utility model and does not limit the utility model in any form. Any ordinary technician in the industry can smoothly implement the utility model as shown in the drawings of the specification and described above. However, any equivalent changes, modifications and evolutions made by technicians familiar with the profession without departing from the scope of the technical solution of the utility model using the technical content disclosed above are all equivalent embodiments of the utility model. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the utility model are still within the protection scope of the technical solution of the utility model.

Claims

1. A low-weight papermaking system, characterized in that: The invention comprises a surface layer headbox (1), a surface layer forming net (2a), a bottom layer forming net (2b), a paper tape composite part (3), a pressing and dewatering part (4) and a post-processing assembly (5), wherein the surface layer forming net (2a) and the bottom layer forming net (2b) are both arranged in the front-to-back direction and spaced apart in the up-down direction, and the paper tape composite part (3), the pressing and dewatering part (4) and the post-processing assembly (5) are arranged in sequence in the front-to-back direction at the rear between the surface layer forming net (2a) and the bottom layer forming net (2b), and the surface layer headbox (1) is arranged on the surface layer forming net (2a). ), the surface layer flow box (1) is used to supply pulp to the surface layer forming net (2a) and the bottom layer forming net (2b), the surface layer forming net (2a) and the bottom layer forming net (2b) are used to respectively make paper tapes (8a), the paper tape composite (3) is used to composite the two paper tapes (8a) into a paper tape composite (8b), the pressing and dewatering component (4) is used to press and dewater the paper tape composite (8b), and the post-processing assembly (5) is used to apply glue, dry and calender the pressed and dewatered paper tape composite (8b).

2. The low-weight paper grade papermaking system according to claim 1, characterized in that: The surface layer headboxes (1) are provided with two, and the two surface layer headboxes (1) are respectively provided corresponding to the surface layer forming net (2a) and the bottom layer forming net (2b), and the surface layer forming net (2a) and the bottom layer forming net (2b) are used to respectively receive the paper pulp delivered by the corresponding surface layer headboxes (1).

3. The low-weight paper grade papermaking system according to claim 2, characterized in that: The invention also comprises a vacuum dewatering box (6) and a vacuum pumping member (7). The vacuum dewatering box (6) is arranged horizontally. The front end of the vacuum dewatering box (6) has two pulp inlets (61) spaced apart from each other in the upper and lower directions. The rear end of the vacuum dewatering box (6) has a paper tape outlet (62). The vacuum dewatering box (6) has a negative pressure interface (63). The air inlet of the vacuum pumping member (7) is connected to the negative pressure interface (63). The surface layer forming net (2a), the bottom layer forming net (2b) and the paper tape composite member (3) are all arranged in the vacuum dewatering box (6). The two pulp inlets (61) correspond to the two surface layer headstock boxes (1) one by one. Each surface layer headstock box (1) feeds pulp into the vacuum dewatering box (6) through the corresponding pulp inlet (61).

4. The low-weight paper grade papermaking system according to claim 3, characterized in that: The vacuum pump (7) is a vacuum pump, and the lower end of the vacuum dehydration box (6) protrudes downward in a conical shape, and a drainage port (64) is provided at the lowest level thereof, and a drainage valve (65) is provided at the drainage port (64).

5. The low-weight paper grade papermaking system according to claim 3, characterized in that: The vacuum pump (7) is a gas-liquid separation device of a high vacuum system.

6. The low-weight paper grade papermaking system according to claim 1, characterized in that: A plurality of the pressing and dehydrating components (4) are provided, and the plurality of the pressing and dehydrating components (4) are arranged at intervals along the front-to-back direction between the paper tape composite component (3) and the post-processing assembly (5).

7. The low-weight paper grade papermaking system according to claim 6, characterized in that: The pressing and dehydrating component (4) is a pressing and dehydrating roller group.

8. The low-weight paper grade papermaking system according to claim 6, characterized in that: The squeezing and dewatering components (4) are provided with two.

9. The low-weight paper grade papermaking system according to claim 1, characterized in that: The post-processing assembly (5) comprises a front-drying component (51), a gluing component (52), a rear-drying component (53) and a calendering component (54) which are arranged in sequence along the front-to-back direction. The front-drying component (51) is used to dry the paper-strip composite (8b), the gluing component (52) is used to apply glue to the surface of the dried paper-strip composite (8b), the rear-drying component (53) is used to dry the glued paper-strip composite (8b) again, and the calendering component (54) is used to calender the surface of the glued and dried paper-strip composite (8b).

10. The low-weight paper grade papermaking system according to claim 9, characterized in that: The post-processing assembly (5) also includes a paper roll (55), and the paper roll (55) is used to roll the paper tape composite (8b) after the calendering treatment.

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