WO2016180899A1

WO2016180899A1 - Continuously operating press

Info

Publication number: WO2016180899A1
Application number: PCT/EP2016/060602
Authority: WO
Inventors: Reto PATTIS
Original assignee: Dieffenbacher GmbH Maschinen- und Anlagenbau
Priority date: 2015-05-11
Filing date: 2016-05-11
Publication date: 2016-11-17
Also published as: EP3294539A1; DE102015107381B4; CN107592835B; DE102015107381A1; CN107592835A

Abstract

The invention relates to a continuously operating press comprising - two endlessly circulating steel belts (3) that pull the material to be pressed (8) through the press (1) and form a press nip between one another for compressing the material to be pressed (8), - temperature-controllable heating plates (10) that support the steel belts (3), - a rolling-bearing support arranged between the steel belts (3) and the heating plates (10), - a plurality of frames (2), arranged transversely to the circulating direction (6) of the steel belts (3), for absorbing the pressing forces which are introduced directly into the heating plate (10) via a plurality of hydraulic working cylinders (4), arranged in a row (R), per frame for compression and for setting the press nip, - an inlet region (KV) for deaerating the material to be pressed (8), and - a pressing section for the material to be pressed (8), which is able to be subdivided into at least two different regions (HD, MD, ND) on account of the embodiment of the frames (2) and/or the hydraulic working cylinders (4). In order to improve the settability in one region (HD, MD, ND), at least two frames (2) are arranged in an offset manner to one another transversely to the circulating direction of the steel belts (3) and/or, within one region (HD, MD, ND), at least one working cylinder (4) of a first frame (2) is arranged in an offset manner to at least one working cylinder of a second frame (2) in the circulating direction (6) of the steel belt (3).

Description

CONTINUOUS WORKING PRESS

The invention relates to a continuously operating press according to the preamble of patent claim 1.

In the large-scale industrial production of wood-based panels usually continuous presses are used. In these presses, as described in DE 39 13 991 C2, the pressing force is transmitted to the pressed material by hydraulic actuators on the press and heating plates and further on steel belts, which are supported by a rolling element carpet (rolling rods) arranged circumferentially. The power flow for the forces generated in the hydraulic actuators is guided and supported substantially by the press racks. Further developments of such presses are described in DE 40 17 791 C2 and
DE 43 40 982 B4 to find.

All this state of the art has in common that along the press line the continuously operating presses are divided into several areas. At the beginning there is the inlet area. This is neglected below, since it is a specific construction of the first compression zone, as known from DE 43 01 594 C2, and is known in the art as a so-called inlet wedge compressor. This takes over the pressed material mat from a loading device and compacts it according to a preset main compaction profile. If the press nip has essentially reached the thickness of the final product, the material is in the high-pressure range (HD), subsequently it reaches the medium-pressure range (MD) and the low-pressure range (ND). The heating and plasticizing takes place essentially in the first two areas. Due to their high required pressing forces, these areas essentially have massive press racks. The low pressure area (ND) usually gives the material plate time to finish bonding.

The main differences between these three areas are the different constructions of the press racks, which are designed for the different maximum forces in order to save manufacturing costs. The differences between these areas are plant technology in different material thicknesses of the frame construction, in the number and size of hydraulic cylinders used per row (transverse to the production direction), in the intervals of the necessary support of the press plates by the press racks and the like. It is also known and to a person skilled in the art, in this case a mechanical engineer, to use parts that are as similar as possible to the same areas with the same requirements and to arrange them symmetrically.

Thus, it is known to arrange different frames for different areas (HD, MD, ND) along a continuously operating press, wherein the same press racks are used in each area and differ the press racks and their embodiments only at the transition between two areas.

Due to the rising costs of metal and steel construction and the possibilities of the FEM in connection with modern PC-based design technology, it has happened that the amount of metal used has been reduced more and more. This has meant that today's presses no longer have the required stiffnesses. At the same time, however, it is also the goal to compensate for temperature-induced deformations of the press by bending and adjusting the press plates and to produce the most accurate possible end product.

For the production of an optimum end product with the most accurate dimensional accuracy, it has been shown disadvantageous that the directly impacted with hydraulic cylinders press plates inaccuracies in their longitudinal and transverse extent, since in the areas without pressurizing the press plate "breathes" and yields along a bending line. This results in poorer thickness tolerances on the material plate to be produced.

WO 2005 046 950 A1 has disclosed a particle or chipboard and a method for its production. This particle plate consists of at least three layers, the outer layers are made of fine material, whereas the middle layer consists of coarser material. In order to save a maximum amount of material, it is intended to produce the plate basically with low material content, only a higher proportion of material to be scattered at the points of the plate, which is later required for the incorporation of fittings or fasteners to compounds to make with other parts. For this purpose, it is proposed to continuously scatter a higher proportion of material on the forming belt or on the already existing lower cover layer in the longitudinal direction or in the production direction of the pressed product mat in order to obtain in the production direction spaced tracks with higher material input of Pressgutmatte after manufacturing have a uniform in length and width plate, a higher density. In addition, by at least one transversely movable to the production direction nozzle at certain points, preferably in the transverse direction stain similar additional material are applied. This serves to obtain from a split strand of strand particleboard having a higher density for mounting fittings or fasteners but using less material and density in the area.

In the production of the nonwoven, a basis weight profile is produced across the width or length of the nonwoven, which of course can also generate different nonwoven heights in consequence. In this case, the density (at different heights) does not necessarily have to be different. If, however, the nonwoven is pressed uniformly across the width, or passes through a press nip which is uniform across the width, it will have different densities due to the different basis weights.

In addition to the problems in the production of a nonwoven fabric difficulties have shown in the compression of a nonwoven with different basis weights. In particular, it is problematic that a continuously operating press with rotating steel belts tends to steel strip course, as different pressures over length and width on the steel bands and possibly. Act on the rolling support. To make matters worse, that the previous support and frame distances can be influenced in unfavorable constellations too much of the resulting density fluctuations or are designed too weak.

The invention has for its object to provide a continuously operating press, which makes it possible to increase the accuracy of the continuous press in a range of equal requirements. As an extension of the task, the calibration area at the outlet of the press, which is responsible for the dimensional accuracy of the end product, should be improved, in particular for material plates with different density profiles along and / or transversely.

The invention is based on a continuous press comprising the following features:
two endlessly circulating steel strips pulling the pressed material through the press, forming a press nip between them for pressing the pressed material,
- temperature controlled heating plates supporting the steel strips,
a rolling bearing support arranged between the steel strips and the heating plates,
- Several arranged transversely to the direction of rotation of the steel bands frames for receiving the pressing forces, which are introduced via several arranged in a row hydraulic cylinder per frame for pressing and for adjusting the press nip directly into the hot plate,
- An inlet area (KV) for venting the material to be pressed
- A press line for the pressed material, which is subdivided into at least two different areas (HD, MD, ND) due to the embodiment of the racks and / or the hydraulic cylinder.

The solution to this problem for this continuously operating press is that in an area at least two frames are arranged offset from one another transversely to the direction of rotation of the steel bands and / or
within a range at least one working cylinder of a first frame is arranged offset to at least one working cylinder of a second frame transversely to the production direction.

Among other systems, a roll bar circulation has been established as a rolling bearing support in this type of presses. Each area has several (press) racks in which several cylinders are arranged, which direct their forces, usually with the interposition of insulation, in the hot plate initiate and adjust the press nip on the back pressure of the material or retraction cylinder. The inlet area is understood in the usual sense as an area, but is to be regarded as a special construction, since here in the foreground is the pressed material by the shortest route to vent and compact. For a finer adjustment of the inlet area but the application of the invention would be quite useful.

As already mentioned, a continuously operating press has several areas with different pressure ranges, based on the maximum possible pressure. The high-pressure area (HD) at the beginning of the press section, the medium-pressure area (MD) and the low-pressure area (ND) at the end of the press section. The low-pressure area is in itself the crucial area for the success of the production of a material plate, since a calibration zone is present here. In this the dimensional accuracy of the material plate is set.

The press racks are designed and constructed constructively on the basis of the maximum expected pressure. In a conventional press about five cylinders are arranged across the width, which in a conventional arrangement provides the ability to regulate the press force profile in five tracks across the width.

The inventive solution is obtained in a favorable manner by a small number of working cylinders a larger differentiated arrangement of the adjustable tracks in the press racks.

This is particularly advantageous if a material plate with different densities over the length and / or width to be produced, which is a challenge for any continuously operating press.

in einer differenzierten Bauweise/Konstruktion der Gestelle,
durch die maximal mögliche Kraftaufnahme,
Unterschiede in den Stützabständen oder der Größe bzw. der Anzahl der Arbeitszylinder der Gestelle,
unterschiedliche Abstände der Gestelle, und/oder
unterschiedliche Druckzonen

Advantageously, the different areas (HD, MD, ND) can be distinguished as follows:

in a differentiated construction / construction of the racks,
by the maximum possible power consumption,
Differences in the support distances or the size or the number of working cylinders of the racks,
different distances of the racks, and / or
different pressure zones

It is preferably provided in a region in the case of several frames that at least two hydraulic working cylinders of two frames form a track (S) parallel to the direction of rotation in the direction of rotation of the steel bands.

Preferably, tracks will be formed on working cylinders that are parallel to the direction of rotation or the direction of production, wherein the tracks are identified by at least four racks, as always two racks define a track by the corresponding arrangement of the working cylinder.

It is preferably provided that at least three racks have alternating rows of cylinders.

Particularly preferred is the embodiment that the same arrangement of the cylinders and the racks in the press every two, three or more racks recurring.

In order to save on additional technical equipment fixed supports can be arranged instead of working cylinders. It is preferably provided that form a same arrangement at a predetermined distance of several frames or their working cylinder, in particular by the working cylinder in a run respectively track. For example, if 10 racks are arranged, it is sufficient, for example, with a doubling of the tracks (4 working cylinders width across the tracks = 8) to provide only two or three active cylinder per track and to provide the remaining support points with fixed supports. Thus, an enlargement of the regulatable tracks can be made possible with approximately the same amount of pressure cylinders in an advantageous manner.

The working cylinders can be double-acting and / or single-acting with retraction cylinders.

In particular, it can be provided that at the outlet of the press for the material plate, a measuring device is arranged, which is suitable across the width, preferably divided into the tracks to perform analyzes on the material plate and is in operative connection with a control or regulating device, the measurement results to control signals for one or more racks and / or working cylinder converts and transmits to this.

Due to the large number of tracks, it is now possible in an advantageous manner to realize a narrower pressure profile across the width in one area, preferably in the calibration area (low-pressure area). This application is particularly advantageous when it is desired to set different density profiles over the width of material plates by pressing differentiated basis weights.

In a further embodiment, working cylinders with different thicknesses or different diameters can be arranged in a row.

Alternatively or cumulatively can be arranged on at least one frame on the edge sides of the heating plate working cylinder with less or greater strength or diameter.

In particular, provision may be made for at least one working cylinder of lesser thickness or smaller diameter to be arranged on at least one frame with a smaller number of identical working cylinders than on at least one adjacent frame.

Further advantageous measures and embodiments of the subject matter of the invention will become apparent from the dependent claims and the following description with the drawing.

In the drawing was dispensed with a complete picture of a continuous press. The prior art already explained and based here is known to the person skilled in the art.

1 shows above a schematic side view of a press 1 with two endlessly rotating steel bands 3 and a production direction 7 from left to right. The steel belts 3 are guided in opposite directions in the direction of rotation 6 to idler pulleys 5 and form between them a press nip for pressing of pressed material 8 and thereby pull the pressed material 8 through the press 1. The steel belts are supported on rolling bearings (not shown) to the in frames. 2 mounted heating plates 10 from which are acted upon in this embodiment from above with working cylinders 4 with pressure, with the working cylinder 4 again supported on the racks 2. In the lower plan view of FIG. 1, the wedge compressor KV can be seen on the inlet side of the press 1. In the production direction 7, the high-pressure region HD, the medium-pressure region MD and the low-pressure region ND follow. The areas HD, MD and ND differ significantly by the design of the working cylinder 4 and the racks 2 from each other. In the exemplary embodiment, the high-pressure area HD has the largest working cylinders 4. These are frame plates in the racks 2, which are designed significantly stronger than the frame plates of the racks 2 in the medium pressure range or low pressure range ND. On a detailed design of the racks is omitted, since the distinctive features between the individual areas are so well explained.

The size and configuration of the working cylinder varies in the direction of production 7 from a high value to a lower value. For example, the working cylinder 4 are still supported in the high pressure area HD with two strong frame plates, which form a frame 2, in the medium pressure range MD, these two frame plates are much thinner, in the low pressure range ND may even be sufficient only a frame plate for supporting the smaller cylinder. 4 provided. This representation is also reflected in the upper drawing, the side view of the continuous press 1 again.

Now, if the low pressure region ND is carried out according to the invention, for example, all two frames 2 of the working cylinder 4 are arranged offset. After four racks forms each by two lying in a line cylinder 4 a parallel to the production direction 7 track S, which are numbered from top to bottom with S1, S2, S3, for example. The number of racks 2 may vary depending on the press, but will be significantly more than the exemplary number of the embodiment.

In the context of the invention, it is also when the racks 2 are offset in the production direction 7 and with them the working cylinder 4, which act on the heating plate 10.

The embodiment of the invention are set very few limits, it can for example only ever in pairs on the frames 2 dislocations occur; For example, two rows of racks remain the same in succession, with the next two or at least one next row Rn + 1 being offset with respect to the rams 4 and / or racks 2, and so on.

Advantageously, the working cylinders of a track or row could be exchanged for solid stops in various variations, provided that each track has at least one, preferably two, in particular preferably four active working cylinders 4 in one area.

The press 1 may be followed by a measuring device 12, in which the compressed material plate 11, preferably in sections over the width, is examined. The one or more measurement results can be automatically transmitted to a control or regulating device 13 and adjusted with respect to the setpoints. The control or regulating device 13 then transmits control or regulating signals to the remote control of the press 1 or directly to the working cylinder 4 and / or the racks 2.

In Figure 2, a separate area is shown in an enlarged view, are arranged in the working cylinder 4 different thickness or with a different diameter D / d. In particular, it is lifted to the outer diameter, the size of which also has physical effects on the force flow behavior in the press 1. In the illustrated embodiment, the working cylinder 4 are made smaller on the outer sides of the heating plates 10, ie at the longitudinal edges of the press 1, and thus have a smaller diameter d. This is particularly useful if by displacing the working cylinder 4 with respect to an adjacent frame 2, a working cylinder 4 with a large diameter D is no longer to be arranged in a row R meaningful and lastflusstechnisch meaningful and thus eliminated. In particular, the embodiment shown is advantageous if bending of the longitudinal edges of the press 1 or the heating plates 10 is to be avoided.

According to Figure 3 is proposed to expand the adjustment options on the press 1 respectively for setting an optimal pressure profile at the longitudinal edges (parallel to the production direction 7), in particular in the low pressure region ND, working cylinder 4 in a smaller embodiment, thus as lesser size respectively smaller diameter d , To order to adjust the bending of the heating plate 10 at the longitudinal edges optimally.

List of Reference Numerals: P1494
1 press
2 frame
3 steel strip
4 working cylinders
5 revolving drum
6 circulation direction
7 Production direction
8 pressed material
9 conveyor belt
10 heating plate
11 material plate
12 measuring device
13 control or regulating device
KV wedge compressor
HD high pressure area
MD medium pressure range
ND low pressure area
R series
S track

Claims

Comprehensive press comprising

- Two endless circulating the pressed material (8) through the press (1) pulling steel bands (3), which form a press nip between them for pressing the pressed material (8),

- the steel strips (3) supporting temperature-controlled heating plates (10),

a rolling bearing support arranged between the steel strips (8) and the heating plates (8),

- Several transverse to the direction of rotation (6) of the steel bands (3) arranged racks (2) for receiving the pressing forces over several in a row (R) arranged hydraulic power cylinder (4) per frame for pressing and for adjusting the press nip directly into the Hot plate (10) are initiated

- An inlet area (KV) for venting the material to be pressed (8),

a press section for the pressed material (8) which can be subdivided into at least two different areas (HD, MD, ND) on the basis of the embodiment of the frames (2) and / or the hydraulic working cylinders (4),

characterized in that

in an area (HD, MD, ND) at least two frames (2) are arranged transversely to the direction of rotation of the steel bands (3) offset from one another and / or

within a range (HD, MD, ND) at least one working cylinder (4) of a first frame (2) to at least one working cylinder of a second frame (2) is arranged offset transversely to the production direction (7).
Press according to claim 1, characterized in that in a region (HD, MD, ND) at least two working cylinders (4) of two frames (2) in the direction of rotation (6) of the steel bands (3) a track (S) parallel to the direction of rotation (6 ) train.
Press according to claim 1, characterized in that the different constructions of the frames (2), and / or the hydraulic working cylinder (4) are characterized by a differentiated

- Construction of the racks (2),

- maximum power consumption,

- Support distances between the racks opposite the heating plate or each other,

- size of the working cylinder (4),

- Number of working cylinders (4) per frame (2) and / or

- maximum pressure zones.
Press according to claim 1, characterized in that form tracks (S), wherein the tracks (S) are identified by at least 4 racks, as always two aligned working cylinder by the arrangement of the racks (2) or the working cylinder (4) itself define a track (S).
Press according to claim 1, characterized in that three frames (2) have a differentiated number of working cylinders (4).
Press according to claim 1, characterized in that fixed supports are arranged instead of working cylinders (4).
Press according to one or more of the preceding claims, characterized in that the working cylinders (4) are double-acting.
Press according to one or more of the preceding claims, characterized in that at the outlet of the press (1) for the material plate (11) a measuring device (12) is arranged, which is suitable over the width, preferably divided into the tracks (S), to carry out analyzes on the material plate (11) and to be in operative connection with a control device (12) which converts and transfers the measurement results to control signals for one or more racks (2) or working rams (4).
Press according to one or more of the preceding claims, characterized in that in a row (R) working cylinder (4) are arranged with different thickness or different diameter.
Press according to one or more of the preceding claims, characterized in that on at least one frame (2) on the edge sides of the heating plate (10) working cylinder (4) are arranged with a smaller or larger thickness or diameter.
Press according to one or more of the preceding claims, characterized in that at least one frame (2) with a smaller number of similar working cylinders (4) than at least one adjacent frame (2) at least one working cylinder (4) with lesser thickness or smaller diameter is arranged.