CN116324086A

CN116324086A - Shoe press for paper and related method

Info

Publication number: CN116324086A
Application number: CN202180067869.6A
Authority: CN
Inventors: F·托奈罗; A·阿尔巴诺
Original assignee: A Celli Paper SpA
Current assignee: A Celli Paper SpA
Priority date: 2020-09-03
Filing date: 2021-08-11
Publication date: 2023-06-23
Also published as: WO2022048877A1; IT202000020926A1; EP4208598A1; BR112023003733A2

Abstract

A shoe press (1) comprises a flexible cylindrical sleeve (5), the flexible cylindrical sleeve (5) co-acting with an opposing roller (205) and defining therewith a pressure nip (8). A shoe (7) is arranged inside the cylindrical sleeve, supported by the support beam (3) by means of a rod (21). The bar (21) is hinged to the support beam (3) about a first hinge axis (25), and the shoe is hinged to the bar about a second hinge axis (23) parallel to the first hinge axis (25).

Description

Shoe press for paper and related method

Technical Field

The present invention relates to improvements in papermaking machinery. Embodiments disclosed herein relate specifically to improvements to shoe presses for reducing the amount of water in cellulosic plies used to produce paper.

Background

In a wet papermaking process, a thin layer of an aqueous suspension of cellulosic fibers is formed on a forming wire. The aqueous suspension layer is dispensed from a headbox arranged in the transverse direction of the forming wire and initially contains a very low weight percentage (typically about 2-10%) of fibers. The moisture content gradually decreases along the feed path, thereby forming cellulose plies having a gradually increasing content of solid portions (i.e., cellulose fibers).

Typically, the first portion of water removal occurs by draining through the forming wire, optionally with the aid of suction rolls or boxes. When the percentage of dry material is high enough to give the cellulose plies formed by gradually removing water from the suspension of cellulose fibers a suitable mechanical strength, the cellulose plies are passed through a drying press and finally through a heating member, such as a dryer or a roll of a yankee cylinder.

In recent years, in order to obtain finer processing of paper (which maintains the thickness of paper as much as possible during the step of removing water by pressing), shoe presses have been developed. Examples of shoe presses and their uses are disclosed in US10697120, US8986506, US7150110, US6517672, US7291249, US6158333, WO 2007/123457.

Typically, shoe presses comprise a flexible cylindrical sleeve with two rigid heads supported by support bearings to rotate about an axis of rotation transverse to the feed path of the mat to which the cellulose plies are adhered. Inside the flexible cylindrical sleeve, a fixed beam extends parallel to the axis of rotation of the flexible cylindrical sleeve and orthogonal to the path of the cellulose plies to be dried. A suitably shaped shoe is mounted on the support beam, the shoe co-acting with and being pressed radially outwardly against the inner surface of the flexible cylindrical sleeve by a plurality of actuators. The flexible cylindrical sleeve cooperates with a rigid counter roller or cylinder having an axis of rotation parallel to the axis of rotation of the sleeve. The sleeve and opposing rollers or cylinders form an extended pressure nip through which an endless flexible element (typically a felt) with a cellulosic ply adhered thereto passes. The shoe presses the sleeve against the opposing roller or cylinder, thereby exerting pressure on the mat and cellulose ply, whereby water is drained from the cellulose ply.

Between the inner surface of the sleeve and the surface of the shoe with which it cooperates, a fluid, typically oil, is dispensed to form a gap that reduces friction between the sleeve and the shoe.

The counter roll or cylinder may be constituted by a counter roll or by a yankee cylinder.

Historically, shoe presses have been used to produce relatively high linear loads (about 1500 kN/m) in the pressure nip for the production of paper and paperboard. These high thrust forces are typically generated by hydraulic actuators that use high pressure oil supplied by a particular hydraulic circuit with an associated pump.

In recent years, shoe presses have been introduced into the field of tissue paper production. In these applications, the shoe press typically acts directly on the yankee cylinder. The linear load applied in the pressure nip is substantially low (about 90-120 kN/m). These loads can be generated by pneumatic actuators instead of hydraulic actuators, thereby significantly simplifying the construction of the press and its drive.

An important feature of shoe presses in the tissue field is that the load distribution can be applied in the pressure nip in the transverse direction (i.e. orthogonal to the direction of feed of the cellulose plies), in particular in the lateral areas (i.e. near the head of the yankee cylinder). This makes it possible to counteract any deformation of the yankee cylinder by means of the pressure distribution.

Another important feature is that the resultant force in the pressure nip can be adjusted in the machine direction (i.e., in the direction of feed of the flexible cylindrical sleeve and felt) to modify a particular pressure profile along the nip. This feature is applied in the water removal process.

WO2004/079090 discloses a shoe press in which the shoe is rigidly fixed to a rod hinged to a support beam inside a flexible cylindrical sleeve which cooperates with a counter-press roller. The shoe press geometry is not efficient because it only allows one angular operating position.

WO2019/138349 discloses a shoe press comprising opposing rollers against which an annular flexible element is pressed by a shoe, the shoe defining a pressure nip with the annular flexible element and the opposing rollers. The shoe is supported inside the annular flexible member by a beam and has a radial movement towards the opposite roller. Furthermore, in order to maintain the annular flexible member in a tensioned state, a support member is also provided inside the annular flexible member, which is positioned at a distance from the shoe and the pressure nip. The inner support element is radially and angularly movable by a dual actuator system to modify its position relative to the boot. The shoe (i.e. the member pressed against the counter member) has only radial movement with respect to the annular flexible element.

It would therefore be beneficial to provide a shoe press that allows for greater efficiency and that overcomes the problems of the prior art shoe presses, either entirely or in part.

Disclosure of Invention

According to one aspect, a shoe press is provided that includes an annular flexible member movable along a closed path. The annular flexible member may be a generally cylindrical sleeve or housing, but this is not required. Furthermore, the press comprises a support beam housed inside the annular flexible element. A boot is supported by the support beam and extends parallel to the support beam inside the annular flexible member. An opposing member is disposed outside the annular flexible element, the opposing member defining with the annular flexible element a pressure nip for passing a ply of cellulose. Furthermore, the press comprises a plurality of actuators aligned along the support beam and adapted to generate a thrust of the shoe against the opposite member, acting on the inner surface of the annular flexible element. The boot is supported by a rod hinged to the support beam about a first hinge axis extending parallel to the support beam. The actuator is arranged to act on the lever to rotate the lever about the first hinge axis. Characteristically, the boot is hinged to the lever about a second hinge axis.

The counter member may be a counter roller or a counter cylinder that rotates, in particular having a peripheral speed that is substantially the same as the peripheral speed of the cellulose ply pressed against it by the shoe press. As will be elucidated below, in the embodiments disclosed herein, the counter member may be a yankee cylinder, in particular a yankee cylinder for producing tissue paper.

With the shoe press according to the prior art, in particular with the shoe press described in WO2004/079070, an important technical effect is obtained with the shoe press according to the invention.

In fact, in the operating principle of the shoe press, two parameters defining the operating position of the shoe are related, namely:

-the distance between the operating surface of the shoe and the surface of the counter-member (e.g. counter-cylinder or counter-roller);

the angular orientation of the shoe, i.e. its inclination.

These two parameters must be kinematically independent of each other, since each parameter depends in a different way on the compressibility of the means interposed between the shoe and the opposite member (polyurethane sleeve forming the annular flexible element, cellulose ply, felt for feeding the cellulose ply) and on the hydraulic counter-pressure generated by the water contained in the material (felt, cellulose ply) and the dynamic conditions of the lubricating oil or other bearing fluid in the gap between the shoe and the inner surface of the annular flexible element. The latter is determined by the speed and physical properties of the oil. In other words, at each given distance of the boot from the opposing member, the boot must freely assume any angular position to adapt to the dynamic conditions. This condition is necessary to ensure the hydrodynamic lubrication function of the shoe and it is very important from a process point of view to obtain the desired pressure distribution in the machine direction to remove the water correctly.

The arrangement shown in prior art patent application WO2004/079090 limits the angular positioning of the shoe by means of the bar to which it is rigidly fixed to its distance from the opposite cylinder and will therefore not function and be unsuitable for the purpose. The shoe press of the present invention solves this problem.

Conveniently, the second hinge axis may be located on the opposite side of the bar to the side facing the support beam, i.e. on the side facing the pressure nip. Furthermore, advantageously, the second hinge axis may be located in an intermediate position of the lever between the first hinge axis and a coupling point of an actuator controlling a movement of the lever about the first hinge axis.

The opposing member may be an annular flexible element, or preferably a rigid roller. The terms "rigid" and "flexible" refer to the relative and normal operating conditions of the shoe press. Thus, the opposing member is a more rigid member (i.e., less deformable under load) relative to the annular flexible member. When the annular flexible element deforms during operation to assume a shape defined by the active surface (typically concave) of the shoe, the opposing members typically do not experience any significant deformation under the load conditions typically applied in shoe presses.

In the embodiments disclosed herein, the counter member may be constituted by a yankee cylinder, or another roll of a dryer of a paper machine.

Typically, the opposed members have a speed of circumferential movement that is substantially the same as the feed speed of the cellulosic plies through the pressure nip.

According to another aspect, disclosed herein is a method for pressing cellulose plies, wherein the cellulose plies are directed through a pressure nip formed between an annular flexible element movable around a support beam and an opposing member located outside the annular flexible element by means of a shoe extending parallel to the support beam and supported on a rod. The rod is hinged to the support beam about a first hinge axis and is pressed against the inner surface of the annular flexible member by a plurality of actuators aligned along the support beam. The boot is hinged to the lever about a second hinge axis.

Further advantageous features and embodiments of the method and the shoe press according to the invention are described below and defined in the appended claims, which form an integral part of the present description.

Drawings

The invention will be better understood from the following description and accompanying drawings, which illustrate non-limiting exemplary embodiments of the invention. More specifically, in the drawings:

FIG. 1 shows a schematic side view of an endless paper machine, wherein a Yankee cylinder cooperates with a shoe press;

FIG. 2 shows a schematic side view of the shoe press;

FIGS. 3, 4 and 5 illustrate an embodiment of the shoe press; and

fig. 6 shows a partial view of the VI-VI according to fig. 3 of a modified embodiment.

Detailed Description

Fig. 1 shows a schematic side view of a tissue making machine 2. The paper machine 2 is known per se and may take on different configurations known to the person skilled in the art. Therefore, the features thereof will not be described in detail.

It is sufficient to mention the following: the paper machine 2 comprises a headbox 201, which headbox 201 forms a cellulosic pulp layer on a forming wire or other water permeable endless flexible member, including a wire and/or felt and indicated generally at 203. The cellulose pulp is gradually drained by known means to reduce its water content until reaching the yankee cylinder 205 which cooperates with the shoe press 1. A mat 203 or other endless flexible element passes between the shoe press 1 and the yankee cylinder 205, and downstream of the shoe press, the cellulosic fiber plies are separated from the mat 203 and adhered to the yankee cylinder for drying. Doctor 207 separates the dried plies (indicated by V) from yankee cylinder 205.

Fig. 2 shows a schematic view of a section according to a plane orthogonal to the axis of the shoe press 1. In this figure, the shoe press 1 cooperates with a yankee cylinder 205. However, it should be understood that the shoe press 1 may be arranged, for example, upstream of the yankee cylinder 205, or be used in a paper machine 2 without a yankee cylinder 205 but provided with a series of drying rolls or other drying means. Thus, the member indicated with 205 in fig. 2 and the following figures may be any other anvil member, preferably in the form of a rotating roller or cylinder, in addition to a yankee cylinder.

As schematically shown in fig. 2, the shoe press 1 comprises a support beam 3, which support beam 3 extends in a transverse direction with respect to the feed direction F of the cellulose ply V on which the shoe press 1 has to act. The support beam 3 is attached at its ends to a load bearing structure, not shown. A flexible cylindrical sleeve 5 having a rotation axis a extends around the support beam 3, said rotation axis a being substantially parallel to the longitudinal extension of the support beam 3 and thus to the transverse machine direction (orthogonal to the feed direction F of the cellulose plies V through the shoe press 1).

A shoe 7 having an active surface 7A in contact with the inner surface of the flexible cylindrical sleeve 5 is arranged between the support beam 3 and the flexible cylindrical sleeve 5. The active surface 7A has a contour shaped to form a pressure nip 8 of suitable shape and extension between the outer surface of the flexible cylindrical sleeve 5 and an opposite surface formed, for example, by the cylindrical surface of the yankee cylinder 205. In a manner known per se, a lubrication gap is formed between the active surface 7A of the shoe 7 and the inner surface of the flexible cylindrical sleeve 5, into which lubrication gap a bearing fluid (e.g. oil) is fed.

In some embodiments, lubrication may be of the hydrostatic type, as is typical in prior art shoe presses. In this case, the bearing fluid is dispensed under pressure through a duct, the end of which opens into a cavity located on the active surface 7A of the shoe 7 of the press 1. The pressure of the bearing fluid is provided by the supply circuit.

Characteristically, in the embodiments described herein, the bearing fluid may be supplied from outside the gap and the pressure may be generated by a hydrodynamic effect, i.e. by the speed difference between the inner (movable) surface of the flexible cylindrical sleeve and the (fixed) active surface 7A of the shoe 7. In this case, the lubrication obtained in the gap between the shoe 7 and the flexible cylindrical sleeve is of the hydrodynamic type.

The two types of lubrication may also be combined.

The counter surface formed by the yankee cylinder 205 or other counter member rotates in the opposite direction relative to the direction of rotation of the cylindrical sleeve 5. The circumferential speeds of the flexible cylindrical sleeve 5 and the opposite surface are substantially the same in absolute value. The shape of the active surface 7A of the shoe 7 and the shape of the opposite surface of the yankee cylinder 205 are substantially complementary to each other so as to form an extended pressure nip 8 of approximately constant height (dimension normal to the opposite surface) along the path of the cellulosic ply through the nip 8.

The yankee cylinder 205 or other counter roller rotates at a feed speed that is substantially the same as the speed of one of the annular flexible members 203, one of the annular flexible members 203 passing through a pressure nip 8 formed between the yankee cylinder 205 and the portion of the flexible cylindrical sleeve 5 pressed against the yankee cylinder 205 by the shoe 7.

Characteristically, the shoe 7 is connected to a rod 21, said rod 21 having a first end 21A hinged to the support beam 3 by means of a hinge defining a first hinge axis 25 parallel to the support beam 3 and to the rotation axis a. Thus, the lever 21 is hinged to the support beam 3 so as to pivot about the first hinge axis 25.

The boot 7 is hinged to the lever 21 by a hinge forming a second hinge axis 23. In practice, the shoe 7 is therefore hinged to the lever 21 so as to rotate about the second hinge axis 23. The hinge axis 23 is approximately parallel to the rotation axis a of the flexible cylindrical sleeve 5 and the first hinge axis 25. At the opposite end 21B, the rod 21 is connected to a thrust actuator 27, said thrust actuator 27 generating a thrust of the shoe 7 against the opposite surface 9. The thrust actuator 27 is schematically shown in fig. 2 and may take various forms, some of which are described below with reference to the remaining figures.

In practice, the shoe press 1 comprises a plurality of actuators 27, said plurality of actuators 27 being aligned along the longitudinal extension of the shoe 7 and the support beam 3, i.e. parallel to the rotation axis a of the flexible cylindrical sleeve 5.

Fig. 3 schematically shows two series of

thrust actuators

27A and 27B, wherein each series of thrust actuators comprises a plurality of actuators aligned in the direction of the longitudinal extension of the support beam 3 and shoe 7.

Each actuator 27 may be a hydraulic actuator. In the preferred embodiment, particularly in the case where the shoe press 1 is associated with the yankee cylinder 205, the actuator 27 is a pneumatic actuator, which has a simpler construction and does not require a hydraulic drive circuit.

The arrangement of the two series of

actuators

27A,27B ensures that a sufficiently high linear pressure is generated in the pressure nip 8.

The

actuators

27A,27B may comprise actuators that utilize synthetic materials, such as synthetic rubber. This type of actuator may include an air spring, a shock spring (torpress), or an equivalent actuator.

In other embodiments, the actuator may comprise a piston-cylinder actuator. Fig. 4 shows an embodiment using multistage pneumatic piston-cylinder actuators, wherein each actuator comprises a cylinder divided into two

chambers

28A, 28B in which two

pistons

29A, 29B connected to a single rod 31 move. The dual actuator thus obtained, also indicated with 27, generates a thrust force which is the sum of the thrust forces generated on the two

pistons

29A, 29B by the pressurized fluid in the two

chambers

28A, 28B. In this way, high thrust is obtained by a compact and simple arrangement.

With the rod 21 and the shoe 7 made of a sufficiently flexible material, it is possible to generate a linear pressure distribution of a desired form along the longitudinal extension of the pressure nip 8, i.e. in a transverse direction with respect to the feeding direction F (machine direction) of the endless flexible element 203 and the cellulose ply V adhered thereto, by using a plurality of actuators 27 controlled independently of each other or in groups.

This makes it possible to counteract any local or global deformation of the opposite surface formed by the yankee cylinder 205 or by another opposite cylindrical member. This is particularly advantageous in case the opposite surface is formed by the outer surface of the yankee cylinder 205, which outer surface of the yankee cylinder 205 may be deformed in use due to its large size and its internal temperature and pressure. For example, and in particular, the Yankee cylinder 205 may expand radially more in the center than near the head, forming a bulge. Autonomous control of the single actuator 27 makes it possible to counteract this differential expansion, avoiding a greater pressure in the points of higher expansion with respect to the points of lower expansion.

While it is generally preferred that each actuator 27 or each pair of multiple series of

actuators

27A,27B aligned along the axis of rotation of the flexible cylindrical sleeve 5 be independent of each other, this is not strictly necessary. For example, the actuators may be divided into a plurality of groups aligned along the longitudinal direction of the support beam 3 and shoe 7 (i.e. parallel to the rotation axis a of the flexible cylindrical sleeve 5). The actuators of each group may be controlled together and the individual groups may be controlled independently of each other.

Fig. 6 schematically shows a modified embodiment, wherein the bar 21 is divided into sections or portions 21C aligned along the longitudinal extension of the support beam 3 and thus parallel to the hinge axes 23, 25. Fig. 6 is a view according to line VI-VI of fig. 3. The configuration of the rod in section 21C can be used in any of the embodiments, as well as in fig. 2, 4 and 5.

Each section 21C of the rod 21 is stressed by at least one respective thrust actuator 27 or by a pair of

thrust actuators

27A, 27B. Dividing the rod 21 into sections 21C allows greater operational flexibility and greater independence of the individual actuators when a load is applied to the shoe 7 that can vary along the extension of the pressure nip 8.

In a modified embodiment, one or more auxiliary actuators 35 may be associated with the boot 7, as schematically illustrated in fig. 5. In a practical embodiment, a series of auxiliary actuators 35 aligned along the linear extension of the shoe 7 may be provided. Also in this case, the auxiliary actuator 35 may preferably be a pneumatic actuator.

The auxiliary actuators 35 may be independent of each other or divided into independent groups.

Each auxiliary actuator 35 is interposed between the shoe 7 and the rod 21. If the rod 21 is divided into sections or segments 21C, as shown in fig. 6, at least one auxiliary actuator 35 may be provided for each segment 21C of the rod 21. The auxiliary actuator 35 allows the shoe 7 to rotate about the second hinge axis 23. In this way, the direction of the resultant force of the pressure exerted by the boot 7 on the opposing surface formed by the yankee cylinder 205 or other opposing member may be modified. If the auxiliary actuators 35 are independent of each other, individually or in groups, a resultant of the pressure forces can be applied in variable directions along the longitudinal extension of the shoe 7.

Although the embodiments described above and shown in the figures are provided with a cylindrical flexible sleeve 5, annular flexible elements other than cylindrical in shape may also be used, for example formed by a belt driven around a series of rollers and forming a non-cylindrical closed path.

In any case, the annular flexible element defines a closed path around the support beam 3, and a pressure shoe 7 is mounted on the support beam 3 by means of a double hinge around the

axes

23, 25, the pressure shoe pressing against the inner surface of the annular flexible element, thereby forming an extended pressure nip between the outer surface of the annular flexible element and the opposite surface of the outer part of the annular flexible element.

In some embodiments, the boot 7 may be made of a composite material. For example, the boot 7 may be made of a material having a matrix composed of a polymer resin, said material comprising reinforcing fibers, such as glass fibers or preferably carbon fibers. In some embodiments, the polymeric material may be an epoxy.

In order to obtain a more efficient operation, the boot 7 may have anisotropic properties, i.e. different physical properties in different spatial directions. For example, the shoe 7 may have different moduli of elasticity in the machine direction (i.e. the direction of feed of the ply V through the pressure nip 8) and in the cross-machine direction (i.e. the direction parallel to the support beam 3 and the longitudinal extension of the shoe 7).

In some embodiments, the shoe 7 may have a higher modulus of elasticity in the feed direction F of the cellulose ply V through the pressure nip 8 than in the cross-machine direction (i.e., parallel to the support beam 3 and transverse to the feed direction F of the cellulose ply V).

Furthermore, in the above description, specific reference has been made to a configuration in which a shoe press is used primarily to reduce the moisture content in the cellulosic plies, and for this purpose the shoe press is coacted with a felt or other flexible conveying member having the cellulosic plies supported thereon, which passes through the pressure nip. However, the features of the novel shoe presses disclosed herein may also be used in calenders in which the cellulosic plies can pass through a pressure nip without support by an endless member. In some embodiments, and vice versa, it is also possible to use, for example, a double flexible conveying member comprising two mats between which the ply V of cellulosic material is held.

Claims

1. A shoe press (1) comprising:

-an annular flexible element (5) movable along a closed path;

-a support beam (3) housed inside said annular flexible element (5);

-a shoe (7), said shoe (7) being supported by said support beam (3) and extending parallel to said support beam (3) inside said annular flexible element (5);

-an opposing member (205), the opposing member (205) being external to the annular flexible element (5) and defining with the annular flexible element (5) a pressure nip (8) for passing a cellulose ply (V), the pressure nip being formed between the opposing member (205) and the shoe (7);

-a plurality of actuators (27; 27a,27 b), aligned along the support beam (3) and adapted to generate a thrust of the shoe (7) against the opposite member at the pressure nip (8);

wherein the shoe (7) is supported by a lever (21), the lever (21) being hinged to the support beam (3) about a first hinge axis (25) extending parallel to the support beam (3), and wherein the actuator (27; 27A, 27B) is arranged to act on the lever (21) to rotate the lever about the first hinge axis (25);

characterized in that the boot (7) is hinged to the lever (21) about a second hinge axis (23).

2. Shoe press (1) according to claim 1, wherein the lever (21) comprises a first end (21A) hinged to the first hinge axis (25), and a second end (21B).

3. Shoe press (1) according to claim 2, wherein the actuator (27; 27a, 27B) acts in the vicinity of the second end (21B) of the rod (21).

4. A shoe press (1) according to claim 2 or 3, wherein the second hinge axis (23) is positioned along the rod (21) between the first end (21A) and the second end (21B).

5. Shoe press (1) according to one or more of the preceding claims, wherein said actuator (27; 27a,27 b) is a pneumatic actuator, in particular a pneumatic piston-cylinder actuator or a pneumatic spring actuator.

6. Shoe press (1) according to one or more of the preceding claims, comprising two series of actuators (27 a;27 b), each series of actuators comprising a plurality of actuators aligned along the direction of the support beam (3) and the shoe (7).

7. Shoe press (1) according to one or more of the preceding claims, wherein said bars are divided into a plurality of sections (21C) positioned side by side along the longitudinal extension of said support beam (3) and said shoe (7).

8. Shoe press (1) according to claim 7, wherein at least one actuator (27; 27a,27 b) acts on each section (21C) of the rod (21).

9. Shoe press (1) according to claim 7, wherein at least two actuators (27 a,27 b) act on each section of the rod.

10. Shoe press (1) according to one or more of claims 7 to 9, wherein the actuators (27; 27a,27 b) of each section (21C) or groups of sections of the rod (21) are controlled independently of each other.

11. Shoe press (1) according to one or more of the preceding claims, wherein at least one of said actuators (27; 27a,27 b) comprises a multistage piston cylinder actuator in series.

12. Shoe press (1) according to one or more of the preceding claims, comprising at least one auxiliary actuator (35), said at least one auxiliary actuator (35) being arranged to act between said rod (21) and said shoe (7).

13. Shoe press (1) according to one or more of the preceding claims, comprising a series of auxiliary actuators (35), said series of auxiliary actuators (35) being arranged to act between the rod (21) and the shoe (7).

14. Shoe press according to claim 13, wherein the auxiliary actuators (35) are controlled independently of each other or in independent groups.

15. Shoe press according to one or more of claims 12 to 14, wherein each auxiliary actuator (35) is a pneumatic actuator.

16. Shoe press (1) according to one or more of the preceding claims, wherein the shoe (7) is made of an anisotropic material having a modulus of elasticity in the direction of feed (F) of the cellulose ply through the pressure nip (8) that is greater than the modulus of elasticity in a direction transverse to the direction of feed (F) of the cellulose ply (V) through the pressure nip (8).

17. Shoe press (1) according to one or more of the preceding claims, wherein the shoe (7) is made of a composite material, preferably a fiber-filled polymer material, preferably a carbon fiber-filled polymer material.

18. A method for pressing a cellulose ply (V), wherein the cellulose ply is led through a pressure nip (8), which pressure nip (8) is formed between an annular flexible element (5) movable around a support beam (3) and an opposing member (205) located outside the annular flexible element (5) by means of a shoe (7), which shoe (7) extends parallel to the support beam (3) and is supported on a rod (21), which rod (21) is hinged to the support beam (3) around a first hinge axis (25) and pressed against the inner surface of the annular flexible element (5) at the pressure nip (8) by means of a plurality of actuators aligned along the support beam (3); wherein the boot is hinged to the lever (21) about a second hinge axis (23).

19. The method according to claim 18, wherein the shoe (7) is pressed at least by an auxiliary actuator (35) acting between the shoe (7) and the rod (21).

20. Method according to claim 18 or 19, wherein the channel between the active surface (7A) of the shoe (7) and the inner surface of the annular flexible element (5) is subjected to hydrodynamic lubrication, or hydrostatic lubrication, or a combination of hydrodynamic lubrication and hydrostatic lubrication.