Press section on a pulp dryer

Abstract

The invention relates to a press group (10) on a pulp dryer. The press group comprises a couch roll press section (11) equipped with a suction roll (14) via which a forming wire (29) is adapted to run, at least two press nips (12, 13) arranged after the couch roll press section, at least one press nip (12) being equipped with a suction roll (15) and at least on one side with a common fabric loop (16). At least two press nips following the couch roll press section are single press nips (12', 13'). The invention also relates to a pulp dryer.

Description

Technical Field

[0001] This invention relates to a press unit on a pulp dryer, comprising:

[0002] - The Gautschpresse section is equipped with suction rollers, and the forming screen is adapted to run via these suction rollers.

[0003] - At least two press nip sections are arranged after the press section, at least one press nip section is equipped with a suction roller, and at least one fabric loop shared by the two press nip sections is provided on at least one side. Background Technology

[0004] A pulp dryer is known, whose wet end includes, for example, a forming section and a subsequent press section. The forming section includes a flat wire. Following the press section is an evaporator dryer and a cutting section located thereon. Sheets are formed in the cutting section. They were packaged together and sold as commercial pulp.

[0005] Figure 3 An example of a press unit according to the prior art is shown. The press section associated with the wet end is typically formed by a so-called combined press section 37. Here, the web W passes through two press zones 12”, 13” in a channel from the forming section to the press section in a supported and guided manner. These two press zones 12”, 13” are formed on suction rollers 15 that move the web W. One of them is formed by rollers 23 of the forming section, and the second is formed by pressure rollers 38 of the lower fabric loop 24” of the web W in the press section. At the end of the forming section, there may be a separate press zone 41, a lump breaker 11. Its main purpose is to break up prematurely formed fiber agglomerations. The lump breaker 11 and the combined press section 37 are so-called suction roller presses. It is also known that a separate boot-shaped press section 18 with drainage on both sides is arranged after the combined press section 37 and before the drying section 103.

[0006] However, there are problems with the wet-end press unit on this pulp dryer. Its disadvantage is that press section 37 may retain a large number of rollers with varying loads and low loading. Furthermore, if the boot press section 18 is part of the press unit, the lead of the web W from the combined press section 37 to the individual boot press section 18 is... Figure 3The area marked by reference numeral 39 in the attached figure is open. This relatively long unsupported lead and low dry matter content of the web can lead to operational problems. Furthermore, if the suction roll 15 assigned to the unit forms two single pressing zones 12”, 13”, their loading will produce a trade-off because the functions of the pressing zones 12”, 13” interact with each other, further affecting the operational capacity and making unsupported operation difficult.

[0007] Another drawback of the combined press section 37 is that the opening in the sleeve of the suction roller 15 often fills with water after the two press zones 12” and 13”. Here, it is difficult to condition the suction roller in the cleaning zone. As the machine speed and press zone load increase, water floats on the suction roller 15 and rotates with it, wetting the fabric traveling in the press zone because the opening cannot be quickly emptied at the end of the suction zone after the second press zone. Summary of the Invention

[0008] The object of this invention is to provide a press unit for a pulp dryer, which has a simpler design, higher operating capacity, and allows the web drying level to reach a higher level before the drying section. Another object of this invention is to provide a wet end for a pulp dryer.

[0009] The press unit adapted to the wet end of a pulp dryer according to the invention has only a single press zone. In one application, a flat roll press precedes the drying section, followed by two single press zones, wherein the first single press zone is equipped with a suction roll. A single press zone here refers to a single press zone arranged only between two rolls, wherein the rolls are adapted to be loaded only relative to each other.

[0010] According to one application, one or more single press zones are adapted to form a boot-shaped press section. According to one application, a fabric loop shared from one side is adapted to run along at least one boot-shaped press section for at least two press zones. Thus, the web is guided in a closed-lead manner onto the third single press in sequence, which is the boot-shaped press section. According to one application, the boot-shaped press section may also be configured as a boot-shaped press section, following at least one other single press zone before the pulp dryer. The two pressure rollers of the boot-shaped press section have their own fabric loops. It is located alone on the lower side of the first boot-shaped press section, and on the boot-shaped press section mentioned last, especially on both sides of the single press zone arranged in front.

[0011] The single-pressing technology according to the present invention improves the function of the suction roller belonging to its pressing zone. With this invention, the opening of the suction roller can be emptied, and water will not flow around the suction roller or fill the holes in the sheath. Furthermore, the single-pressing solution has the advantage that a single pressing zone is significantly easier to design and operate well compared to, for example, two matched roller pressing zones in a combined pressing section.

[0012] In particular, compared to known combined pressing sections in the prior art, the first boot-shaped pressing section achieves wide load control, where loading occurs briefly relative to the roller pressing zones that are suspended from each other. Because the pressing zone of the boot-shaped pressing section is bend-compensated, it is always straight regardless of the load. Therefore, the straight, bend-compensated boot-shaped pressing section is significantly superior to the second and third pressing zones of the boot-shaped pressing section according to the prior art, where the load and roller flexure must always meet the same narrow load range.

[0013] The result of this invention is that the dry matter content of the web after the pressing section is 1-3% higher than that of the pressing section according to the prior art, which includes combined pressing. This reduces energy consumption in the evaporative drying process and also reduces dust in the dryer, for example, during waste removal. Furthermore, it has been found that the first open lead has a higher dry matter content than, for example, the case of combined pressing according to the prior art. This reduces the risk of web tearing to some extent. As a result of this invention, the same rollers / shrouds can also be used in different pressing zones. Other advantages achieved by this invention will be set forth in the specification and the characterizing portion of the claims. Attached Figure Description

[0014] The invention will now be described in more detail with reference to the accompanying drawings, but is not limited to the application forms shown below, wherein:

[0015] Figure 1 A schematic example of the pressing unit as seen from the side is shown.

[0016] Figure 2 An example of the wet end of a pulp dryer as viewed from the side is shown, and

[0017] Figure 3 An example of a pressing unit according to the prior art is shown. Detailed Implementation

[0018] exist Figure 1 The diagram shows a schematic example of a press unit 10 on a pulp dryer, viewed from the side. Along the running direction of the web W, the press unit 10 includes a flat roll press section 11 and at least two subsequent press zones 12, 13 before the drying section 103.

[0019] The flat roll press section 11 is located at the end of the forming section 101. The flat roll press section 11 is equipped with a suction roller 14 arranged below the pressing zone 41. The forming web 29 of the forming section 101 is adapted to operate about this suction roller, and the web W is guided to the flat roll press section 11. Therefore, the suction roller 14 also functions as a guide roller 29 for the forming web and is equipped with a driver. The loaded roller 30 of the flat roll press section 11 is the upper flat roll 31. For this purpose, a loading mechanism 33 is arranged on the flat roll 31. Thus, the suction roller 14 and the flat roll 31 together form the first pressing zone 41 of the press unit 10. The fiber accumulation of the fiber web on the flat roll press section 11 is broken down, that is, the web W is broken down, but the web W is also flattened more evenly.

[0020] The flat roller press section 11 follows at least two press zones 12, 13, which are part of the actual press section 102, along the running direction of the web W. At least one of these press zones 12, 13 is equipped with a suction roller 15. This press zone equipped with the suction roller 15 is now the first press zone 12 following the flat roller press section 11, which, in the press unit 10 according to the invention, is in the sequence of the second press zones. Furthermore, the press zones 12, 13 are equipped with a common fabric loop 16 from at least one side. In the illustrated application, the flat roller press section 11 is also arranged as part of the common fabric loop 16 that follows the two single press zones 12', 13', and due to this arrangement, this fabric loop can now also be referred to as the upper fabric loop.

[0021] The press section 102 includes at least two press zones 12, 13 that follow the roll press section 11 along the running direction of the web W, just as the individual press zones 12', 13' of the roll press section 11. For example, compared to the combined press section 37 consisting of three rolls, it improves and simplifies the controllability of dewatering of the web W. If the press zones 12, 13 are independent and separate press units formed by two rolls arranged opposite each other, then adjustments to the loading of these press units only affect themselves, thus improving the runnability of the web W and providing more precise control over dewatering. For example, if the press zones are traveling with separable loading, then with the present invention, the loading of one press zone does not affect the loading on the second press zone, as would occur, for example, in the combined press section 37 with three rolls.

[0022] In the at least two single press zones 12', 13' equipped with a common upper fabric loop 16, the first single press zone 12' is adapted to form an upper suction roller 15 forming the press zone 12 and a guide roller 23 that serves as a guide roller for the lower forming web 29 of the press zone 12, and is equipped with a driver. Thus, the fabric circulation 28 of the forming web 29 extends from the couch press section 11 to the single press zone 12'. The common fabric loop 16 of the plurality of press zones 12, 13 extends at least through the guide roller 20 between the couch press section 11 and the subsequent single press 12' equipped with the suction roller 15. At least one fabric adjuster 27 may be arranged before and / or after the guide roller 20. Accordingly, it may also be arranged before the couch press section 11.

[0023] In at least two single-press zones 12', 13' equipped with a common fabric loop 16, the suction roller 15 of the first single-press zone 12' is adapted to the machine base structure 34 of the pressing section 102. Therefore, the suction roller 15 is secured above to the machine base 34 of the pressing section 102 by a bearing housing, and the pressure roller 23, serving as a guide roller for the forming web 29, is correspondingly secured to the lower machine base of the forming section 101 and equipped with a loading mechanism 32 for loading the suction roller 15. By supporting the two rollers 23, 15 on the machine base, loading control is improved compared to, for example, a combined pressing section 37. Here, the support for the suction roller 15 occurs floatingly on the same machine platform as the roller 38 of the next pressing zone 13", and its own loading mechanism is also arranged on both sides of the suction roller 15, which is adapted to act on the two pressing zones 12" and 13" of the combined pressing section 37. Now, according to the present invention, independent control of the loading can be achieved using single pressing zones 12' and 13', and therefore it can be done more precisely.

[0024] According to one application, the sleeves 14', 15' of the flat press section 11 and the suction rollers 14, 15 of the first single press zone 12' equipped with at least two single presses 12', 13', are adaptively adjusted relative to each other. Here, the length and diameter of the sleeves 14', 15' of the suction rollers 14, 15 can be equal. The two sleeves 14', 15' can also have holes, making the sleeves 14', 15' replaceable. In the press unit 10, the thickness of the sleeve 15' of the second sequential single press zone 12' of the suction roller 15 can be as thin as the thickness at the suction roller 14 of the flat press section 11. This improves the spare parts supply at the wet end of the pulp dryer when multiple components that differ significantly from each other are not required. Therefore, the two suction rollers 14, 15 can share the main components, and for example, only the suction zone / suction box can differ from each other. The suction roller pressing zone can have the same pressing zone loading range. For example, it can be 40-60 kN / m.

[0025] According to one application, in at least two single-press zones 12', 13' equipped with a common fabric loop 16, the latter (i.e., the third single-press zone 13' in sequence) is adapted in the press unit 10 according to the invention to be formed by a boot-shaped press section 18. Therefore, the guidance of the web W from the single-press zone 12' surrounding the suction roller 15 to the boot-shaped press section 18 occurs in a supported guiding manner along the entire path up to the fabric 16'. Here, the single press 12' including the suction roller 15 is adapted to the auxiliary material W such that it allows attachment to the fabric 16', through which the web is supportedly guided to the boot-shaped press section 18 beneath the fabric 16'. Therefore, of the at least two single-press zones 12', 13' equipped with a common fabric loop 16, the first single-press zone 12' is adapted to act as a transfer zone 26 to loosen the web W from the forming web 29, transfer it to the actual press section 102, and be guided into the boot-shaped press section 18 in a manner supported on the fabric 16'.

[0026] According to one application, the winding angle α of one or more suction sections of at least two single-press pressing zones 12', 13' equipped with a common fabric loop 16 following the first single-press pressing zone 12' of the press fabric 16' is 25-120 degrees after the single-press pressing zone of the suction roller, preferably 40-90 degrees in one or more suction chambers 40. Therefore, for example with... Figure 3Compared to the combined press section 37 known according to the prior art, the winding angle of the suction section in the technical solution according to the present invention is longer because, in the combined press section 37, the fabric 16' is only briefly wound on the suction chamber after the second press zone 13'. Therefore, the pressed fabric 16' does not immediately "leave" from its suction roller 15' after the press zone 12, i.e., return to the fabric loop 16, but continues for a distance on the associated suction roller 15 after the press zone 12'. Here, the suction roller 15 has a longer suction chamber 40 after the press zones 12, 12' than, for example, in the standard combined press section 37. Therefore, the suction roller 15 is adapted to, by means of the suction chamber 40, remove the fabric 16' from the press zone 16' before the subsequent second single press zone 13'. Moisture is removed, and the fabric 16' does not wet, for example, the supported and guided web W being transported to the single press zone 13'. The good operation of the suction roller 15 is further improved in the embodiment of the invention because water is only pressed into the fabric 16' in one press zone 12. In the combined press section 37 according to the prior art, the fabric winding on the transfer suction roller is longer than that in the embodiment of the invention because there the fabric 16' will continue to travel along the direction of the suction roller 15 to the return portion of the fabric loop 16. Therefore, in the embodiment of the invention, the fabric 16' is released from the suction roller 15 earlier because its movement along the machine direction MD will continue to the next single press zone 13'.

[0027] On the boot-shaped press section 18, dewatering of the web W is carried out in two directions using fabric loops 16, 24 on both sides. In the illustrated application, the upper fabric loop 16' is together with the previous single press zone. The lower fabric loop 24 is adapted to the boot-shaped press section 18's own fabric loop 24 so as to run through the single press zone 13'. The upper fabric loop 16 returns to the flat press section 11 via guide rollers after the boot-shaped press section 18. Thus, a common fabric loop 16 is arranged on at least two single press zones 12', 13', where the latter is configured as the single press zone 13' of the boot-shaped press section 18, partially adapted to the forming section 101. Here, the fabric loop 16 can, for example, extend one meter from the flat press section 11 along the direction of the headbox 110.

[0028] For at least two single-press zones 12' and 13', where the latter is the single-press zone 13' implemented as a boot-shaped press section 18, the pulling / driving of the common fabric loop 16 is adapted to occur on the guide roller 20 before the suction roller 15 and on the boot-shaped press section 18 of the fabric 16'. Therefore, the transfer suction roller 15 can also be implemented without driving. With this invention, the pick-up fabric 16' is also advantageously 2-12 meters longer than the upper fabric 16” of a typical combined press section 37. This compensates for the larger load generated on the boot-shaped press section 18.

[0029] According to one application, the press unit 10, particularly the pressing section 102, also includes a fourth single-press zone 19' preceding the pressing section 103. According to another application, this fourth single-press zone 19' is, in sequence, a second boot-shaped pressing section 19 in the press unit 10. The second boot-shaped pressing section 19 is also equipped with its own fabric loops 21, 22 on both sides. This allows for supplementary dehydration of the independently adjustable single pressing zones 12', 13', and achieves optimal overall dehydration results.

[0030] According to one application, the boot-shaped press sections 18 and 19 can also be identical, advantageously having common spare parts. According to one application, the boot-shaped press sections 18 and 19 are adapted to be at least compatible with each other to the roller sleeve 17. Here, the sleeves 36' of the boot rollers 35.1, 35.2 and / or the opposing rollers 36.1, 36.2 are mutually compatible. If the same roller sleeves 17, 36', loading mechanisms, and other spare parts associated with the two boot-shaped press sections 18 and 19 can be used in this boot-shaped press section 18 and 19, this simplifies the spare parts supply for the press section 102.

[0031] The boot-shaped press sections 18 and 19 are formed by so-called boot rollers 35.1 and 35.2 and opposing rollers 36.1 and 36.2 arranged for this purpose. The boot rollers 35.1 and 35.2 can be loaded relative to the opposing rollers 36.1 and 36.2. Here, an elongated pressing zone is formed between the rollers along the machine direction MD. In this pressing zone, the surface of the boot 25 follows the shape of the surface of the opposing rollers 36.1 and 36.2.

[0032] The protective sleeve 17 of the shoe rollers 35.1 and 35.2 is formed by a belt loop. This belt loop rotates about the shoe 25, for example, by fastening it to the end flange of the roller. This belt loop is adapted to rotate about the loading shoe 25 by means of a pair of rollers 36.1 and 36.2 equipped with a drive, pulled by the pressure contact portion. Inside the belt loop is a medium-lubricated shoe 25, which has a loading and support mechanism (not shown). The shoe 25 and the loading mechanism are supported on a pressure shaft (not shown) located inside the shoe rollers 35.1 and 35.1, which is generally I-shaped in profile when viewed in basic cross-section in the loading region.

[0033] Inside the sheath 17 are the boots 25 of the boot rollers 35.1 and 35.2, adapted to the pressure shaft. The boots 25 are located on one side of the opposing rollers 36.1 and 36.2 and are adapted to load them. The boots 25 have a loading mechanism, which is also arranged similarly within the sheath 17. The boots 25 of the boot rollers 35.1 and 35.2, together with the opposing rollers 36.1 and 36.2, form the aforementioned single press zones 13' and 19'. The boots 25, sometimes also referred to as pressure boots or sliding boots, are elongated and lubricated by a medium between the sliding surface of the sheath 17 and the boot 25.

[0034] The loading device of the shoe 25 may include, for example, one or two rows of hydraulic cylinders with loading pistons that act on the shoe 25, either via a pressure plate or directly. During loading, and due to the concave shape of the shoe 25, the sections of the rollers 36.1, 36.2 are slightly pressed, as in the shoe rollers 35.1, 35.2, thus the single press zone 13' becomes elongated (e.g., 100-320 mm) along the machine direction MD. The rollers 36.1, 36.2 may also include a shoe-shaped loading system. Advantageously, the rollers 36.1, 36.2 are bend-compensating rollers. The rollers 36.1, 36.2 are essentially used to pull the two rollers through pressure zone contact. The rollers in this unit can also be exactly the opposite.

[0035] The loading range of the boot-shaped press sections 18 and 19 can be, for example, 100-1250 kN / m. In the case of two boot-shaped press sections 18 and 19, the loading range of the first boot-shaped press section 18 along the running direction of the web W can be, for example, 400-700 kN / m, and the loading range of the second boot-shaped press section 19 can be, for example, 1000-1250 kN / m. The first boot-shaped press section 18 particularly allows for wider loading control compared to, for example, the combined press section 37, which has fixed roller sleeves at the pressure zones 12” and 13”.

[0036] Figure 2 This diagram illustrates, in principle, an example of the wet end of a pulp dryer as viewed from the side. The wet end of the pulp dryer includes a headbox 110, a forming section 101, and subsequently a press section 102. Following the press section 102 is the drying section 103, sometimes also called a trockenschrank. The direction of travel of the web W and the fabric is indicated by arrows. The pulp exiting the lip opening of the headbox 110 is delivered onto the flat wire section 101.1 belonging to the forming section 101, on the surface of its lower wire ring, or its forming wire 29. The delivered pulp first encounters the forming roll 111, along which the forming wire 29 is adapted to travel.

[0037] According to the illustrated application, the forming section 101 is now horizontal, and in the illustrated application, it primarily includes a flat wire section 101.1, in which water is removed from the pulp to be conveyed from the headbox 110 to the forming wire 39, for example, a strip dewatering section 112. Therefore, this dewatering occurs at least in one direction along the entire main length of the forming section 101, which is now downwards. A fabric loop is arranged on the forming wire 29, in which different dewatering mechanisms, such as the strip dewatering section 11 described above, are arranged in the flat wire section 101.1. Instead of the flat wire section 101.1, the forming section 101 can also be a horizontal clamping forming device (not shown). Here, the pulp is fed directly into the gap between the two fabric loops.

[0038] Furthermore, the forming section 101 now also includes an upper dewatering section arranged in the flat web section 101.1, which has a fabric circulation 113, a fabric conditioner 114, and a dewatering mechanism 115 arranged therein. In other words, a web-feeding unit 101.2 is arranged on the flat web section 101.1 so that dewatering is also performed upwards. The web-feeding unit 101.2 is arranged at least partially in the flat web section 101.1, or rather, along the length of the forming section 101 in the machine direction MD, now in the rear half. It can be noted that the forming section 101 ends at the flat roll press section 11, from which the web W is guided by the forming web 29 to a single press zone 12' equipped with a suction roller 15, where the pressure roller 23, as a guide roller of the forming web equipped with a driver, serves as the opposite roller of the suction roller 15. The suction roller 14 of the forming web 29 guides the forming web 29 and the web material W located thereon at the end of the forming section 101, where the web material bends towards its siphon suction roller 15 in specific sections of the forming web. At the height of the suction section of the suction roller 14 of the forming web 29, there is a pressure roller 30 arranged opposite to it from the side of the web material W; this pressure roller is a so-called flat roller 31 (block crusher). Its purpose is to seal the web material W relative to the suction roller 14 of the forming web 29, improve the strength of the web material W, and reduce the amount of fiber accumulation in the web material W. The dry matter content of the web material W is typically about 20% after the forming section 101.

[0039] like Figure 1As shown in the application, according to one application, the press unit 10 may include a press unit 10 with a single press according to the invention. In the application shown, it includes four single press zones 41, 12, 13, 19. Here, it includes two successively arranged suction roller press sections or flat roller press sections 11 and a subsequent single press zone 12' equipped with an upper suction roller 15. Accordingly, at least one, or two in the application shown, single press zones 13', 19' are adapted such that the two single press zones are now boot-shaped press sections 18, 19. The first boot-shaped press section 18 is adapted here to be part of the same fabric loop 16 on one side, having at least the forward-arranged single press zone 12' including the suction roller 15, and in the application shown, also having the flat roller press section 11. The second boot-shaped press section 19 is equipped with its own fabric loops 21, 22 on both sides. Figure 2 The image also shows a waste conveyor 117 with a waste handling unit 116.

[0040] The differences between pulp drying and papermaking are, for example, significantly different weight per unit area: 600-1000 g / m² for pulp, a maximum of about 550 g / m² for paperboard, and a maximum of about 150 g / m² for paper. Furthermore, pulp dryer speeds are typically less than 200 m / min, while paper machine speeds can exceed 1600 m / min. Additionally, the temperature of the semi-pulp drawn from the headbox in a pulp dryer is at least 55°C in older machines, and typically above 60°C, preferably about 70°C, in newer machines, while in a paper machine this temperature is typically below about 45°C. Perhaps one of the most specific differences is that paper / paperboard is always the final product, and its requirements are completely different from those of dried pulp as raw material. The requirements for dried pulp mainly involve treatment during the drying process, handling of the dried pulp, transport in the paper mill, and dissolution. The pulp dryer does not attempt to significantly affect the properties of the actual pulp sheet. Conversely, in the manufacturing process of paper and paperboard, the quality characteristics of the final product determine the process, such as smoothness, gloss, opacity, and imprinting. This demonstrates that the conditions in a pulp dryer are significantly different from those in a paper machine; in fact, the technical solutions implemented on a paper machine are generally unsuitable for the pulp machine environment.

[0041] It should be understood that the above description and related drawings are for illustrative purposes only. Therefore, the invention is not limited to the embodiments described above or defined in the claims; on the contrary, many variations and modifications will be apparent to those skilled in the art, which are possible within the framework of the inventive concept defined by the appended claims.

Claims

1. A press unit on a pulp dryer, comprising: - The flat roller pressing section (11) is equipped with a suction roller, and the forming net (29) is adapted to run via the suction roller. - At least two pressing zones (12, 13) are arranged after the pressing section (11), at least one pressing zone (12) is equipped with a suction roller, and at least one side is equipped with a fabric ring (16) shared by at least the two pressing zones (12, 13). The feature is that at least two pressing zones (12, 13) following the pressing section (11) are single pressing zones (12', 13'). In at least two single press zones (12', 13') equipped with a common fabric loop (16), the first single press zone (12') is adapted to form the suction roller and a pressure roller (23) that can be loaded relative to the suction roller and serves as a guide roller for the forming web (29).

2. The pressing unit according to claim 1, characterized in that, In at least two single press zones (12', 13') equipped with a common fabric loop (16), the latter being a first boot-shaped press (18) with bend compensation, on which the web (W) is adapted to achieve a guide supported by the fabric loop (16).

3. The pressing unit according to claim 1 or 2, characterized in that, In at least two single-press zones (12', 13') equipped with a common fabric loop (16), the suction roller of the first single-press zone (12') is adapted to the machine structure (34) of the pressing section (102).

4. The pressing unit according to claim 2, characterized in that, In at least two single-press zones (12', 13') equipped with a common fabric loop (16), the first single-press zone (12') is adapted to serve as a transfer zone (26) for disengaging the web (W) from the forming net (29) and transferring it to the actual press section (102).

5. The pressing unit according to claim 1 or 2, characterized in that, The winding angle (α) of one or more suction sections in at least two single press zones (12', 13') of the press fabric (16') following the first single press zone (12') is 25-120 degrees after the first single press zone (12') of the suction roller.

6. The pressing unit according to claim 5, characterized in that, The winding angle (α) is 40-90 degrees.

7. The pressing unit according to claim 3, characterized in that, The pressing section (102) includes a fourth single pressing zone (19'), which is adapted before the drying section (103).

8. The pressing unit according to claim 7, characterized in that, The fourth single-press zone (19') is, in sequence, the second boot-shaped press section (19) of the press unit (10) for bending compensation.

9. The pressing unit according to claim 8, characterized in that, The second boot-shaped press (19) is equipped with its own two side fabric rings (21, 22).

10. The pressing unit according to claim 8, characterized in that, The first boot-shaped pressing section (18) and the second boot-shaped pressing section (19) are compatiblely adapted to the roller sleeve (17).

11. The pressing unit according to claim 1 or 2, characterized in that, The sheaths (14', 15') of the suction roller of the press section (11) are adapted to be compatible with the sheaths (14', 15') of the first single press zone (12') of the at least two single press zones (12', 13') equipped with a common fabric ring (16).

12. The pressing unit according to claim 2, characterized in that, The common fabric loop (16) is used for at least two single press zones (12', 13'), wherein the latter is partially adapted to the forming section (101) as a second single press zone (13') implemented as a first boot-shaped press section (18).

13. The pressing unit according to claim 1 or 2, characterized in that, For at least two single-press zones (12', 13'), the latter being the second single-press zone (13') implemented as the first boot-shaped press section (18), the pulling / driving of the common fabric loop (16) is adapted to occur on the guide roller (20) before the suction roller of the first single-press zone (12') and on the first boot-shaped press section (18).

14. The pressing unit according to claim 1 or 2, characterized in that, For the flat roller pressing section (11), one or more of the following are implemented: - Adapt the press section (11) to be part of the common fabric loop (16) of the two single press zones (12', 13'), and / or - The loaded roller (30) of the flat roller pressing section (11) is a flat roller (31).

15. A wet end of a pulp dryer, comprising: - Molding section (101) - Press unit (10), including: - The flat roller pressing section (11) is equipped with a suction roller, and the forming net (29) is adapted to run via the suction roller. - After the pressing section (11), at least two pressing zones (12, 13) are arranged, at least one pressing zone (12) is equipped with a suction roller, and at least one side is equipped with a fabric loop (16) shared by at least the two pressing zones (12, 13). The characteristic feature is that the pressing unit (10) corresponds to any one of claims 1 to 14.

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