EP0799931B1 - Cylinder press - Google Patents

Abstract

`A roller press for a, esp. paper mfg., machine has a suction press roller (4) which with an encircling felt (6) accepts a material web (A), e.g. cardboard or paper, from a machine wire (1) etc. and a delivery press roller (7) forming a pressure gap (B) with the suction roller and taking the web for delivery to a following machine section. An auxiliary press roller (14, 24) is assigned to suction and delivery rollers to form an additional pressure gap (R, S) with each. A press felt (15, 25) is led over each auxiliary and at least one of the additional gaps is extended in the direction in which the web runs.

Description

The invention relates to a roller press of a machine such as in particular a paper machine with a material web like in particular a cardboard or paper web from one Screen or the like taking over suction press roll with assigned around the suction press roll and press felt one with the suction press roll forming a press nip, the Material web from the delivery press roll taking over the suction press roll to deliver the material web to a subsequent one Part of the machine (see FR-A-2 355 117).

Such a roller press is used in particular for dewatering the material web in question. Here is the respectively achieved Drainage capacity, among other things, by the number dependent on the press nips. An increase in the number of press nips however, there are usually limits. So it was already proposed, that of the suction press roll and the delivery press roll formed pair of rollers at least one more separate pair of rollers to form a respective additional Downstream of the nip. The resulting one However, space requirements are considerable. Are also problematic the resultant between the respective pairs of rollers open trains.

The aim of the invention is to provide a roller press of the type mentioned To create the kind that takes up a minimum of space higher press performance, i.e. a higher drainage capacity ensures.

The object is achieved according to the invention in that both the suction press roll and the delivery press roll in each case at least one additional press roll is associated with the suction press roll or the delivery press roll at least in each case to form an additional press nip, being about each additional press roll in turn guided a press felt is and that at least the additional press nip between the delivery press roll and the associated additional press roll is an extended press press.

This training results in an extremely compact Roller press with high press performance. In the simplest case results a three-nip roller arrangement from only four rollers with double-sided drainage in the Area of the first press nip between the suction press roll and the associated additional press roll, at least one unilateral drainage in the area of the press nip between the suction press roll and the delivery press roll and at least one unilateral drainage in the area of the third press nip between the discharge press roller and that assigned to it additional press roll. It also emerges from the sieve-side takeover point to the delivery point a closed path with pre-drainage of the Cardboard or paper web. Because of the minimum reduced rewetting can be a maximum Achieve dryness. Due to the lack of open trains between There is also any paper stretch in the roller assemblies locked out. There are no losses in wet strength on. The first open move only follows to the press arrangement with maximum wet strength. A crucial one The advantage of the invention is particularly in that too see that due to the at least one extended additional Press nip despite the extremely compact roller arrangement a significantly higher press performance or drainage performance is achieved.

It is particularly advantageous here if at least the additional one Press nip between the discharge press roll and the assigned an additional press roll an extended Press nip is.

In a practice preferred embodiment of the The roller press according to the invention lies over the suction press roller the assigned press felt for the direct takeover of the Material web on the sieve. This is the simplest of construction the takeover of the material web is considerably simplified.

Advantageously, at least one of the additional press rolls a deflection compensation roller with a rotating one Roll shell, a yoke penetrating the roller shell and at least one hydrostatic and / or hydrodynamic Support element by which the roller jacket is supported on the yoke is.

In a preferred embodiment, the suction press roll is the discharge press roll and the additional press rolls in such a way arranged and / or stored that the forces of the press nips are short-circuited to each other and not by the machine foundation and / or a possibly provided outside seating be included.

According to a preferred embodiment variant of the invention provided that the discharge press roll at least one as Deflection compensation roller trained additional press roller with a flexible roller jacket, the flexible one Yoke passing through the roller jacket and at least one not convex hydrostatic and / or hydrodynamic support element is assigned to one in with the discharge press roll Direction of the material web to form an extended press nip.

Because of the difference between the discharge press roller and the associated one additional press roll resulting extended press nip is made from maintaining a compact, a small number of rollers existing roller assembly achieved an optimal drainage performance.

Preferably, the suction press roll is at least one as Deflection compensation roller trained additional press roller with a flexible roller jacket, the flexible one Yoke passing through the roller jacket and at least one not convex hydrostatic and / or hydrodynamic support element assigned to one in the direction of rotation with the suction press roll the material web to form an extended press nip, whereby achieved a further optimization of the drainage performance becomes.

The dispensing press roll can also advantageously be a deflection compensation roll with a circumferential roller jacket, a yoke penetrating the roll shell and at least a hydrostatic and / or hydrodynamic support element by which the roller jacket is supported on the yoke.

It preferably has one as a deflection compensation roller trained delivery press roll a rigid roll shell. In principle, however, this roller can also be used with a flexible jacket.

The roll shell of a deflection compensating roll Dispensing press roll can be used at least during operation be radially fixed at its ends. So that are radial movements at least essentially during operation locked out. Thus, even under pressure a position to be maintained.

Especially in the case that the delivery press roll at least an additional designed as a deflection compensation roller Press roll is assigned and also the discharge press roll is a deflection compensation roller, the hydraulic actuated hydrostatic and / or hydrodynamic Support elements of the additional press roll and the delivery press roll advantageously coupled hydraulically be what, for example, in connection with a position control is an advantage.

The delivery press roll is used to achieve the best possible conditions preferably without the possibility of radial Deflection in a defined position on a stand attached, which in turn is firmly mounted on the machine foundation is.

The discharge press roll can act as a deflection compensating roll with a flexible roller jacket, the flexible roller jacket penetrating yoke and at least one non-convex hydrostatic and / or hydrodynamic support element be designed to with the associated additional press roll and / or suction roll in the direction of travel of the material web to form an extended press nip.

Is also the additional assigned to the discharge press roll Press roll a deflection compensation roll with a flexible Roll shell, so can advantageously the support elements the discharge press roll and the associated additional Press roll on their facing roll shell Side be at least essentially flat, to form an at least substantially flat press nip.

In certain cases it may be useful, at least one of the rollers as a deflection compensation roller with radial form displaceable roll shell. In this case the roll shell in question is preferably rigid.

In principle, however, it is also possible to use one flexible roller jacket to use.

Again, to achieve the most defined possible conditions is expediently at least that between the delivery press roll and the associated additional press roll Press nip during operation through appropriate position control held firmly in a certain position.

The suction press roll can be a hollow roll with a be supported on the inside of the roller jacket. In this case, the suction roll is preferably with an outer one Provide suction box through which a located inside the roller Area is suctioned off.

Further advantageous design variants are in the subclaims specified the roller press according to the invention.

Figur 1

eine vereinfachte schematische Teildarstellung einer Ausführungsform einer Walzenpresse,

Figur 2

eine vereinfachte schematische Darstellung einer weiteren Ausführungsform der Walzenpresse,

Figur 3

eine Teildarstellung der in Figur 2 gezeigten Walzenpresse mit angedeuteten Kraftflußverläufen in den Spaltbereichen,

Figur 4

die in Figur 2 gezeigte Walzenpresse in einer Phase, in der der Preßfilz für die Saugpreßwalze ausgewechselt wird,

Figur 5

die in Figur 2 gezeigte Walzenpresse in einer Phase, in der der Preßfilz für die der Abgabepreßwalze zugeordnete zusätzliche Preßwalze ausgewechselt wird,

Figur 6

die in Figur 2 gezeigte Walzenpresse in einer Phase, in der der Preßfilz für die der Saugpreßwalze zugeordnete zusätzliche Preßwalze ausgewechselt wird,

The invention is explained in more detail below on the basis of exemplary embodiments with reference to the drawing; in this show:

Figure 1

a simplified schematic partial representation of an embodiment of a roller press,

Figure 2

a simplified schematic representation of a further embodiment of the roller press,

Figure 3

2 shows a partial representation of the roller press shown in FIG. 2 with indicated force flow profiles in the gap areas,

Figure 4

the roller press shown in Figure 2 in a phase in which the press felt for the suction press roll is replaced,

Figure 5

the roll press shown in Figure 2 in a phase in which the press felt for the additional press roll associated with the discharge press roll is replaced,

Figure 6

the roll press shown in Figure 2 in a phase in which the press felt for the additional press roll associated with the suction press roll is replaced,

In Figure 1 is a simplified schematic representation a roller press of a machine, in particular a paper machine shown. This roller press includes one a material web such as a cardboard or paper web in particular A from a screen 1 taking suction press roll 4 with an associated, around the suction press roll 4 guided press felt 6 and one with the suction press roll 4 forming a press nip B, the cardboard or paper web A from the suction press roll 4 Dispensing press roller 7 for dispensing the cardboard or paper web A an adjoining machine part.

As can be clearly seen, for example, from FIG. 1 is, the suction press roll 4 lies over the associated press felt 6 on the screen 1 so that the material web A immediately takes over.

Both the suction press roll 4 and the discharge press roll 7 an additional press roll 14 or 24 is assigned, around with the suction press roll 4 or the discharge press roll 7 each form an additional press nip R, S. Here is in turn a press felt over each additional press roll 14, 24 15, 25 out.

This shown in Figure 1 end of a wire section of the paper machine further comprises screen rolls 2, 3 around which the screen 1 is performed. Here, the suction press roll 4 lies above the assigned one Press felt 6 in the between the two screening rolls 2, 3 listed area on sieve 1.

The cardboard or paper web A formed on the screen 1 becomes through the press felt 6 and the suction press roll 4 from the screen 1 lifted and then one after the other through the three press nips R, B and S performed. This takes place in the first press nip R between the suction press roll 4 and the associated one additional press roll 14 double-sided drainage due to the pressing action of the suction press roll 4 or the additional press roll 14 associated press felt 15. In contrast, takes place in between the suction press roll 4 and the Dispensing press roll 7 formed nip B only one unilateral drainage due to the suction effect of the Suction press roll 4. Im between the discharge press roll 7 and the this associated additional press roll 24 formed Press gap S also occurs again one-sided Drainage on what by that of the additional press roll 24 associated press felt 25 is reached.

In the embodiment shown in Figure 1 is the suction press roll 4 as a hollow roller with a rigid roller shell 30 trained, which can be supported on its inside and revolves around a core 32.

Here, the suction press roll 4 with an outer suction box 34 provided by an area located inside the roller 36 is suctioned off.

In the embodiment shown in Figure 1 are both additional press nips R and S in the direction of travel of the material web A extended. The same applies in the present case for the press nip B between the suction press roll 4 and the discharge press roll 7.

For this purpose, both the two additional press rolls 14, 24 as well as the discharge press roll 7 each as a deflection compensation roll with a circumferential roller jacket 17, 26, 38, a yoke 16 passing through the roll shell and at least a hydrostatic and / or hydrodynamic support element 18, 27, 40 formed through which the roll shell in question 17, 26, 38 supported in the respective gap area on the yoke 16 is. The roll shell 38 of the discharge press roll 7 is thus not only in the area of the press nip S, but over the at least one hydrostatic and / or hydrodynamic Support element 40 also in the area of the suction press roll 4 formed press nip B supported.

The roller jacket 26 of the deflection compensating roller, the discharge press roll 7 associated additional Press roll 24 is flexible. The one that can be seen in FIG. 1 additional press roll 24 assigned hydrostatic and / or hydrodynamic support element 27 is on its Roller jacket 26 associated side is not convex, in the present Case just trained. The same applies to that the opposite discharge press roller 7 assigned hydrostatic and / or hydrodynamic support element 27, which the in the present case also flexible roll shell 38 of Dispensing press roll 7 supports. This results in an Direction of travel of the cardboard or paper web A extended level Press nip S.

In contrast, this is on the opposite side of the yoke 16 of the dispensing press roll 7 arranged support element 40 a concave contact surface, through which the flexible Roller jacket 38 against the rigid roller jacket 30 of the suction press roll 4 is pressed. Here too, however, there is a running direction the cardboard or paper web A extended press nip B formed.

Also the additional press roll assigned to the suction press roll 4 14 is again a deflection compensation roller with flexible Roller jacket 17, the flexible roller jacket 17th penetrating yoke 16 and at least one non-convex hydrostatic and / or hydrodynamic support element 18 educated. In the present case, this has a support element 18 a concave contact surface. This extends over a larger part of the circumference of the suction press roll 4 than that concave contact surface of the support element 40. Between the suction press roll 4 and the associated additional press roller 4 thus becomes one in the running direction of the cardboard or paper web A longer press nip R.

In particular, the one assigned to the discharge press roll 7 additional press roller 24 can also be used with a roller jacket be provided, the recesses for receiving press water owns. These recesses can be in the form, for example of circumferential grooves and / or blind holes.

The yokes 16 of the deflection compensation rollers are at least stationary during operation. In addition, in particular the dispensing press roll 7 is provided with a roll shell be radial at least at its ends during operation is fixed.

According to Figure 1, the suction press roll 4, the discharge press roll 7 and the additional press roller 24 assigned to it on a straight line that forms an angle with the vertical, in the present case, for example, about 45 ° is. The additional pressure roller assigned to the suction pressure roller 4 14 is arranged on the right below the suction press roll 4. The one running through the axes of these two rollers Just forms with the through the suction press roll 4, the discharge press roll 7 and the additional press roller assigned to it 24 straight lines at right angles.

In the embodiment shown in Figure 2 is that of the discharge press roll 7 assigned additional press roll 24 directly arranged above the dispensing press roll 7, so that the straight line extending through the axes of these two rollers in Vertical direction. Otherwise, the one in FIG roller press shown essentially the same structure like the press shown in Figure 1. Corresponding to each other Parts have been assigned the same reference numerals.

The respective storage of the Rollers.

So the discharge press roll 7 without the possibility of a radial Deflection in a defined position on a stand 42 attached, which in turn is firmly on the machine foundation 44 is mounted.

The jacket of the discharge press roller 7 can at least during the Operating at least substantially radially fixed at its ends be, so that it is essentially under pressure maintains unchanged position.

Position control can ensure that the press nip S remains in a predetermined position. In this position makes him independent of the respective one Pressing force and the respective machine speed. For this purpose, at least one position sensor and one Press force control for at least one of the concerned Support elements may be provided.

As can be seen in particular from FIGS. 2 and 3, are the rolls 4, 7, 14 and 24 forming the three press nips braced against each other during operation and / or connected that practically none Pressing forces are absorbed by other frame elements have to. These are only assigned to the roll neck or to accommodate the bearing parts bearing the roller yokes.

In Figure 3 they are in the area of the three press points resultant corresponding power flow curves through bold Lines indicated. Accordingly, result from the respective Press gaps in self-contained lines of force, which leads to that the generally relatively high press forces only from the assigned bearing parts that support the roll neck or the yokes must be included. The other chair elements therefore do not need to be designed for these high pressing forces his.

The connecting elements provided between these bearing parts can be solved for a roll or fabric change become.

In Figure 4, the roller press of Figure 2 is in one phase shown, in which the press felt 6 for the suction press roll 4th is replaced. After loosening the connecting elements to the dispensing press roll 7 and to the additional press roll 14 the press felt 6 from a cantilever 46 on the leader or carried freely by the operator. This is on the drive side supported. Previously, those shown in Figure 2 were Intermediate pieces 48 removed, first of all the one above Bearing arrangement was raised by means of a crane.

The one previously tensioned over a deflection roller 50 (see FIG. 2) Press felt 6 is partially wound onto a roller 52 according to FIG. 4.

FIG. 5 shows the roller press of FIG. 2 in one phase, in which the press felt 25 assigned to the discharge press roll 7 additional press roll 24 is replaced after beforehand again the corresponding intermediate pieces 48 (cf. Figure 2) have been removed.

To replace this press felt 25, the connecting elements are first the additional press roll 24 to the dispensing press roll 7 and for chairs on the driver's side. Then the additional press roller 24 by another Yoke attachable support device raised to which the Felt was draped beforehand.

The one previously tensioned over a deflection roller 54 (see FIG. 2) Press felt 25 is partially on a roller 56 according to FIG. 5 wound up.

The frame chair is only for carrying the felt running devices and to take up the own weights of the Pressing devices provided. It is therefore not used for recording of pressing forces exerted on the cardboard or paper web.

The frame frame can be placed in the upstream and screen section can be integrated and for a screen change corresponding interruption devices provided on the driver's side have. This is the frame from the cantilever of the suction press roll 4 on the Driver's side worn.

The entire press arrangement has no parts of the frame the paper machine on the machine floor, i.e. that before the driver 's machine beam on which the Frame stand and the stand of the dispensing press supported are free of such parts of the stool.

According to Figure 6 for a change of the additional Press roll 14 guided press felt 15 the additional press roll 14 after loosening the connecting elements on the driver's side to the suction press roll 4 on the driver's side by a Yoke of the press roll 14, the attachable support device is lowered, around which the new felt was previously draped. In the Support device can be, for example, a push-on tube act.

The roll press can be used for a respective roll change have a crane rail that runs across the paper machine and should at least fulfill the following functions:

This crane rail 58 is initially intended to be used as an extension aid serve the drive end of the suction roll 4. Further it is used as a run-in aid for carrying the drive end of the felt retractor for the Suction press roll 4 associated press felt 6. Finally, can it also as a run-in aid for carrying the drive end serve the felt retractor for the press felt 25, the around the additional press roll 7 assigned to the discharge press roll 24 is performed.

The roller press according to the invention has, inter alia, the following advantages:

There is a closed web guide from the screen side Admission point until the end of the press. Overall is low rewetting ensures what a maximum dryness. After between press existing open trains are missing, no paper stretching occurs and also no loss of wet strength. The first open tension after the press is at maximum wet strength. After only one transfer point after the press section maximum wet strength is guaranteed.

It can also be done with a production width variation always a constant paper width through all press nips or Ensure nips. A variable edge strip runs on the Central roller. It is also essential that felts and rollers can always be used with the same paper width. The the desired high dry content can also be achieved achieve with just one shoe press, which is a smaller number of rollers.

In addition, there is an extremely compact design, which except the space saving especially for problem-free conversions is essential.

There is a direct flow of force for all nips. A portal chair not applicable. There are no external ones on the driver's side Stand provided. In front of the machine there is more Free space created. There is no ceiling load.

Furthermore, for easy access through the bridge chairs worried. A respective felt and roller change is possible without any problems. It is also for better Accessibility for adjustment, maintenance and cleaning work worried.

If there is no cross member above the press, one results optimal nip arrangement as a 4-roller NipconFlex combi press.

With a fixed driven central roller (Nipco-P roller) results in a stationary web running geometry after the press after this roller is mounted on a stand is. A stable scraper connection is also possible. The arrangement is also insensitive to drive vibrations.

In addition, there is a high level of operational reliability for a respective shoe press in such an installation position. Due to the closed web inspection, the risk of chunks is raised reduced to a minimum. Manual threading (using a glass tube) as well as the two nips for pre-calibration in front of the shoe press. With inverted shoe arrangement this results in optimal press jacket lubrication.

Despite its compact design, changing the roller is relatively easy possible. The press rolls take up little time interchangeable independently. It can for All press roll extension devices can be provided. It results a short-term use of the crane. Basically is also a roll change without a crane, for example possible via rails in front of the machine.

The press felt assigned to the suction press roll can be fully cantilevered his. The felt can be easily moved through a felt change entry device be replaced.

The top felt is by means of a press jacket changing device portable. It can in turn be a felt change entry device be provided.

The bottom felt is portable (slip-on tube on Nipco yoke). Internal extendable felt guide rollers can be provided his.

It also improves accessibility for Scanpro measurements reached.

Ultimately, the overall result is an inexpensive press concept. Having no separate NipcoFlex press provided only a few reserve rollers are required. Because of the small space requirement also results in a small one Share of construction costs.

Reference list

1

scree

2nd

Screen roller

3rd

Screen roller

4th

Suction press roll

6

Press felt

7

Dispensing press roller

14

additional press roll

15

Press felt

16

yoke

17th

Roller shell

18th

Support element

24th

additional press roll

25th

Press felt

26

Roller shell

27

Support element

30th

Roller shell

32

core

34

Suction box

36

Area

38

Roller shell

40

Support element

42

Stand

44

Machine foundation

46

Cantilever

48

Spacers

50

Pulley

52

roller

54

Pulley

56

roller

A

Paper web

B

Press nip

R

additional press nip

S

additional press nip

Claims (24)

1. Roll press for a machine, such as in particular a papermaking machine, having a suction press roll (4) which picks up a material web (A), such as in particular a paper or board web, from a wire (1) or the like and has an associated press felt (6) that is led around the suction press roll (4), and having a hand-over press roll (7) which, with the suction press roll (4), forms a press nip (B) and picks up the material web (A) from the suction press roll (4), to hand the material web (A) over to a following part of the machine, both the suction press roll (4) and the hand-over press roll (7) each being assigned at least one additional press roll (14, 24) in order, with the suction press roll (4) and the hand-over press roll (7), to form at least one additional press nip (R, S) respectively, and, in turn, a press felt (15, 25) being led over each additional press roll (14, 24), characterized in that at least the additional press nip (S) between the hand-over press roll (7) and the associated additional press roll (24) is an extended press nip.
2. Roll press according to Claim 1, characterized in that the suction press roll (4) rests on the wire
      (1) via the associated press felt (6) and picks up the material web (A) directly.
3. Roll press according to one of the preceding claims, characterized in that the suction press roll (4), the hand-over press roll (7) and the additional press rolls (14, 24) are arranged and/or mounted in such a way that the forces of the press nips (R, B, S) are mutually short-circuited and are not absorbed by the machine foundation and/or any external framing which may be provided.
4. Roll press according to one of the preceding claims, characterized in that at least one of the additional press rolls (14, 24) is a controlled deflection roll having a revolving roll cover (17, 26), a yoke (16) passing through the roll cover (17, 26) and at least one hydrostatic and/or hydrodynamic supporting element (18, 27), by means of which the roll cover (17, 26) is supported on the yoke (16).
5. Roll press according to Claim 4, characterized in that the hand-over press roll (7) is assigned at least one additional press roll (24) which is designed as a controlled deflection roll and has a flexible roll cover (26), a yoke (16) passing through the flexible roll cover (26) and at least one non-convex hydrostatic and/or hydrodynamic supporting element (27), in order, with the hand-over press roll (7), to form a press nip (S) that is extended in the running direction of the material web (A).
6. Roll press according to Claim 4 or 5, characterized in that the suction press roll (4) is assigned at least one additional press roll (14) which is designed as a controlled deflection roll and has a flexible roll cover (17), a yoke (16) passing through the flexible roll cover (17) and at least one nonconvex hydrostatic and/or hydrodynamic supporting element (18), in order, with the suction press roll (4), to form a press nip (R) that is extended in the running direction of the material web.
7. Roll press according to one of the preceding claims, characterized in that the hand-over press roll (7) is assigned at least one additional press roll (24) which is designed as a controlled deflection roll and has a rigid roll cover (26).
8. Roll press according to one of the preceding claims, characterized in that the suction press roll (4) is assigned at least one additional press roll (14) which is designed as a controlled deflection roll and has a rigid roll cover (17).
9. Roll press according to one of the preceding claims, characterized in that the roll cover of at least one controlled deflection roll is provided with recesses to accommodate press water in the relevant press nip.
10. Roll press according to one of the preceding claims, characterized in that the hand-over press roll (7) is a controlled deflection roll having a revolving roll cover (38), a yoke (16) passing through the roll cover and at least one hydrostatic and/or hydrodynamic supporting element (27, 40), by means of which the roll cover (38) is supported on the yoke (16).
11. Roll press according to Claim 10, characterized in that the hand-over press roll (7) designed as a controlled deflection roll has a rigid roll cover (38).
12. Roll press according to Claim 10 or 11, characterized in that the roll cover (38) of the hand-over press roll (7) designed as a controlled deflection roll is fixed radially at its ends, at least during operation.
13. Roll press according to one of the preceding claims, characterized in that the hand-over press roll (7) is assigned at least one additional press roll (24) which is designed as a controlled deflection roll, in that the hand-over press roll (7) is a controlled deflection roll, and in that the hydraulically operated hydrostatic and/or hydrodynamic supporting elements (27) of the additional press roll (24) and of the hand-over press roll (7) are coupled hydraulically to one another.
14. Roll press according to one of the preceding claims, characterized in that the hand-over press roll (7) is preferably fitted such that it can rotate on a stand (42), on which it can be fixed in a defined position without the possibility of radial deflection, the stand (42) in turn being firmly mounted on the machine foundation.
15. Roll press according to one of the preceding claims, characterized in that the hand-over press roll (7) is a controlled deflection roll having a flexible roll cover (38), a yoke (16) passing through the flexible roll cover (38) and at least one non-convex hydrostatic and/or hydrodynamic supporting element (27, 40), in order, with the associated additional press roll (24) and/or the suction press roll (4), to form a press nip (R) that is extended in the running direction of the material web (A).
16. Roll press according to Claim 15, characterized in that the additional press roll (24) assigned to the hand-over press roll (7) is a controlled deflection roll having a flexible roll cover (26), and in that the supporting elements (27) of the hand-over press roll (7) and of the associated additional press roll (24) are designed to be at least essentially level on their side facing the relevant roll cover (26), in order to form an at least essentially level press nip (S).
17. Roll press according to one of the preceding claims, characterized in that at least one of the rolls is designed as a controlled deflection roll with a radially displaceable roll cover.
18. Roll press according to one of the preceding claims, characterized in that at least the press nip (S) formed between the hand-over press roll (7) and the associated additional press roll (24) is held firmly in a specific spatial position during operation by means of an appropriate position control system.
19. Roll press according to one of the preceding claims, characterized in that the suction press roll (4) is a hollow roll that has a roll cover (30) that revolves around a core (32) and is supported on the inside.
20. Roll press according to one of the preceding claims, characterized in that the suction press roll (4) is provided with an external suction box (34), by means of which suction is applied to an area (36) in the interior of the roll.
21. Roll press according to one of the preceding claims, characterized in that in order to replace at least one of the press felts (6, 15, 25), a respective felt-change insertion device is provided.
22. Roll press according to one of the preceding claims, characterized in that in order to replace the press felt (6) for the suction press roll (4), a cantilever support (46) is provided, which carries the press felt (6) in an unsupported manner.
23. Roll press according to one of the preceding claims, characterized in that in order to replace the press felt (25) for the additional press roll (24) assigned to the hand-over press roll (7), this additional press roll (24) can be raised by a supporting device which can be fixed to its yoke (16) and around which the press felt (25) can be draped in advance.
24. Roll press according to one of the preceding claims, characterized in that in order to replace the press felt (15) for the additional press roll (14) assigned to the suction press roll (4), this additional press roll (14) can be lowered by means of a supporting device which engages on its yoke (6), such as in particular a push-on tube or the like, around which the press felt (15) can be draped in advance.

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