EP3917739B1 - Device and method for producing insulating panels - Google Patents

Description

The invention relates to a device with a first and a second zone for producing insulation or soundproofing panels from a pressed material mat which consists at least partially of lignocellulosic particles wetted with binding agents, wherein the first zone is designed for heating and/or compacting the pressed material mat and the second zone is designed for hardening the pressed material mat with the aid of calibration plates,
and wherein driven rotating screening belts are provided in contact with the upper and lower material mat surfaces.

The invention further relates to a method for producing insulation or soundproofing panels from a pressed material mat which consists at least partially of lignocellulosic particles wetted with binding agents, using the device mentioned.

Such a device is, for example, in the EN 10 2008 039 720 B4 In some cases, such devices are connected in series with pre-compression devices or after-acting pressing devices, e.g. continuous presses, but these are not important within the scope of the invention. The products produced on the device are offered, for example, by SOPREMA GmbH under the name Pavatex or by H. Henselmann GmbH + Co KG under the name Gutex. Binders that can be used include those based on the principle of polycondensation or polyaddition, such as PMDI.

DE102007044161 A1 discloses a plant for producing insulation boards consisting of a defibration device, a drying device, a gluing station, a pre-compaction unit, a spreading device with a forming belt arranged underneath and a subsequent calibration and curing unit, wherein the plant comprises several screening belts and pre-pressing belts.

Within the scope of the invention, insulation boards with densities of 100-240 kg/m ² should preferably be able to be produced. The sieve belts, or sieves for short, serve to guide the pressed material mat through the device at a desired speed by driving them at the same speed as the mat is to be transported. Steam can be introduced into the pressed material mat from the outside through the sieve, or liquid and air can be removed.

In such devices, it has been found that the screens, which are made of plastic or wire mesh, reach their tensile load limits when the drive power is exceeded. This inevitably leads to limited productivity (current limit of around 8 t/h for a 60 mm thick mat of pressed material), because if the permeable belts have a maximum tensile strength, this results in a limitation in the length of the curing section, which depends on the product density. The required curing time of the binding agent and the maximum length of the curing section determine the achievable speed.

On the other hand, in order to increase production, one would like to increase the production speed, which is therefore the task of the invention.

With regard to the device, the object is achieved by the features of claim 1.

The term "active contact" also refers to a contact where another circumferential porous belt runs between the pressed material mat and the sieve belt. This means that there are separate sieve belt systems for two zones, each the width of the pressed material mat. In each zone, at least one sieve belt is arranged above the pressed material mat and one sieve belt is arranged below the pressed material mat. The inventors have recognised that the load on the sieve belt is particularly high in the compression or steam heating area, i.e. in the first third of the entire device. For this reason, a separate sieve belt is used on both sides of the pressed material mat for the first zone, which can be driven independently of the sieve belts that operate in the curing area, i.e. the second zone. This means that the absorption of the resulting tensile forces is distributed between two belt systems. If the available drive power is used for a total of at least four sieve belts, significantly higher speeds of the sieve belts and pressed material mat are possible than previously. Calculations and tests have shown that at least 15 t/h of the desired insulation boards can be produced with such a device. The capacity can therefore be increased considerably if the friction forces of the screen belts acting on the conveyor belts at the top and bottom are distributed over several belt revolutions. so that a longer device for the production of insulation boards can be realized with the available sieve belts.

The at least four screening belts each have their own drive.

This means that each screen belt can be pushed to its limits. The tension on the screen belt can be recorded using suitable sensors and the results can be incorporated into the drive control system. This means that the drive torque can be kept within a permissible range. Driven deflection rollers are usually used to drive the screen. It is also advantageous if a device for applying steam to the mat of material to be pressed is provided in the first zone and a device for air cooling the mat of material to be pressed is provided at the end of the second zone.

The higher speed achievable with the invention allows for higher productivity with slightly higher energy input or slightly increased device length. This provides the energy required to harden the pressed material mat and its binding agent. The steam is designed in such a way that it penetrates at least to the middle of the pressed material mat and heats it. It can also be a steam-air mixture, in which case the dew point can also be set. On the opposite side of the pressed material mat, at least some of the moist air is preferably sucked out again or a vacuum is created by means of a suction system in order to assist the penetration depth of the steam into the pressed material mat and to reduce the curing time in the second zone. It is advantageous if there are at least two steaming stations in the first zone, one of which applies steam to the pressed material mat from above and the other from below. The first zone, which will be referred to below as the "steaming zone" to simplify readability in the description, is generally somewhat shorter than the second zone, which will be called the "curing zone".

The final purpose of air cooling is to cool the hardened pressed material mat to such an extent that no harmful processes, such as hydrolysis, can occur after it leaves the device and impair the quality of the panel.

Preferably, the device has a height-adjustable inlet.

The required drive power for the pressed material mat depends to a large extent on the thickness of the pressed material mat and its compaction. Since customers want to change their production temporarily and the product thickness preferably varies between 5 and 240 mm, an adjustment may be necessary to achieve additional compaction or to increase the distance to be adjustable between a sieve belt on the upper side of the material mat and a sieve belt on the lower side of the material mat.

This is advantageously ensured if a steaming device is arranged in the inlet.

By steaming the mat in the inlet area, the frictional forces that arise during transport of the mat are already greatly reduced because the mat to be pressed becomes softer.

The calibration plates are preferably heatable plates.

Calibration plates 3 are therefore arranged in the zones and preferably in zone 2. These can be heated using different systems. Examples of possible systems include channels with heating fluid, inductive heating, electrical heating or steam heating, whereby the latter can also release the steam directly to the mat of material to be pressed. This can accelerate the hardening process of the binding agent, so that the length of the device remains within reasonable limits.

Preferably, the first and second zones are immediately adjacent to each other.

In this context, immediate means that there is a maximum distance of 0.2 m in the direction of travel of the mat of material to be pressed between the last screen belt deflection roller in the steaming zone and the first screen belt deflection roller in the curing zone. This prevents energy loss to the environment of the heat required for curing in the device.

It is particularly advantageous if a sliding shoe is arranged between two screen belt deflection rollers, bridging the gap between the screen belt deflection rollers and the material mat or a screen belt.

If a mat of material to be pressed is guided over the gusset between two screen belt deflection rollers, there is a risk that the mat of material to be pressed expands under pressure and causes damage in the transition from the steaming zone to the curing zone or suffers damage itself. This is particularly critical in the transition area from the first to the second zone and can therefore be used sensibly there, because there is no further support in this area, for example from a calibration plate. To prevent the mat from expanding and thus causing damage, a sliding shoe extending across the width of the mat of material to be pressed is arranged between the screen belt deflection rollers. In direct contact with the mat of material to be pressed, it is then guided over the maximum 0.2 m long transition on the shoe surface. The sliding shoe has a flat sliding surface facing the mat of material to be pressed and its side walls are shaped so that they are adapted to the contour of the deflection rollers. In cross-section, this can be triangular, for example, with the hypotenuse (sliding side) being straight and the legs being curved to match the contour of the deflection rollers.

With regard to the method, the object of the invention is solved by the features of claim 8.

Further method claims correspond analogously to the device claims and exploit the aforementioned advantages.

• Fig. 1 eine schematische Darstellung einer ersten Ausführungsform der Erfindung
• Fig. 2 eine schematische Darstellung einer zweiten Ausführungsform der Erfindung,
• Fig. 3 eine schematische Darstellung einer dritten Ausführungsform nicht gemäß der beanspruchten Erfindung,
• Fig. 4 eine schematische Darstellung eines Ausschnitts mit überbrückendem Gleitschuh zwischen Zone 1 und 2

In the following, the invention is explained in more detail using drawings showing exemplary embodiments.

• Fig.1 a schematic representation of a first embodiment of the invention
• Fig. 2 a schematic representation of a second embodiment of the invention,
• Fig.3 a schematic representation of a third embodiment not according to the claimed invention,
• Fig.4 a schematic representation of a section with a bridging sliding shoe between zones 1 and 2

Fig.1 shows a schematic side view of the device according to the invention for producing insulation boards. Between an upper rotating screen belt 5a and a lower rotating screen belt 5d, a mat of pressed material, which consists at least partially of lignocellulosic particles wetted with binding agents, is treated in a first zone Z1 and a second zone Z2. The separation of the zones is indicated in all figures by a dash-dotted vertical line.

In the past, the mat to be pressed was heated with steam or a steam-air mixture within the upper and lower sieve circuits and finally hardened by applying heat via calibration plates. Speeds could only be achieved up to the tensile strength limits of the sieves.

In Fig.1 you can now see that two further rotating sieve belts are arranged within the rotating upper sieve 5a and the rotating lower sieve belt 5d. In the upper part of the device they are designated 5b and 5c, in the lower part of the device they are designated 5e and 5f. All rotating sieve belts 5a - 5f have their own drive, which is implemented via the driven deflection rollers 8.

In the front part of the device, in which the mat 2 in the inlet 9 springs back due to the compaction until the When the material to be pressed mat is softened by the steam 4a and 4b, a large part of the frictional power that the drive had to overcome is generated. With the invention, this zone Z1 receives two separate rotating sieve belts that are driven separately. This reduces the tensile load on the long rotating sieves 5a and 5d. The same applies to zone Z2, in which the material to be pressed mat 2 hardens. Here, too, a separate rotating and driven sieve belt 5c, 5f is provided both above the material to be pressed mat 2 and below it, which provides part of the transport power. Overall, significantly higher speeds can be achieved with this arrangement.

In zone 1, i.e. within the rotating sieve belts 5b and 5e, devices for applying steam 4a, 4b are also provided. The steam penetrates through the rotating sieves 5a and 5b or 5d and 5e into the pressed material mat 2 and condenses. Escaping residual steam and residual air can be removed via the suction devices 6a and 6b.

A further device for applying steam 4c can be arranged, for example, in the inlet 9. The moist surface produced also reduces the friction on the sieve belts 5a and 5d, which leads to additional energy savings.

In zone 2, effective calibration plates 3 are therefore arranged, which can be heated by different systems. For example, channels with heating fluid, inductive heating, electrical heating or steam heating systems, whereby the latter can also release the steam directly to the pressed material mat in the curing zone.

The mat of material to be pressed is cooled at the outlet of the device by an extraction system 6c, which draws cool air 14 from the environment through the mat of material to be pressed 2 in the form of an air cooling system 11.

In Fig.2 and 3 For reasons of clarity, the pressed material mat and the driven deflection rollers and the inlet have been omitted. Fig. 2 differs as a possible second embodiment of Fig.1 This is now achieved by omitting the rotating screens 5c and 5f. This is possible with some types of insulation boards without any major losses in the drive pitch on the at least four rotating driven deflection rollers being expected.

Fig. 3 then shows as a further embodiment, not according to the claimed invention, that the long rotating sieve can be dispensed with entirely. In the upper part of the device, therefore, only the sieve belts 5b and 5c are shown.

Since this naturally creates a gap between zones 1 and 2, as the deflection rollers 7 of the sieve belts 5b and 5c can come into close contact with one another, a sliding shoe 13 extending over the width of the pressed material mat 2 is inserted into the gusset 12 between two deflection rollers 7 of the two zones 1 and 2 and the pressed material mat. This allows the pressed material mat to be If possible, the gap should be less than 200 mm long and should not expand and cause damage. List of reference symbols 1 Device for producing insulation boards 2 Press mat 3 Calibration plate 4a, 4b, 4c Device for applying steam 5a, 5b, 5c, 5d, 5e, 5f Sieve belt 6a, 6b, 6c Suction device 7 Deflection roller 8th Driven deflection roller 9 enema 10 Inlet height adjustment 11 Air cooling 12 gore 13 Sliding shoe 14 Cooling air supply Z1, Z2 Zones 1 and 2

Claims (13)

1. Device with a first and a second zone (Z1, Z2) for producing insulating or acoustic panels from a press material mat (2), which consists at least in parts of lignocellulose particles coated with binding agents, wherein the first zone (Z1) is designed for warming and compressing the press material mat, and the second zone (Z2) is designed for hardening the press material mat with the aid of calibration plates (3),

   and wherein driven, circulating sieve belts (5a-5f) are provided that are in contact with the upper and the lower press material mat surface, wherein at least four circulating sieve belts (5a-5f) can be used in such a way that arranged within an upper sieve belt (5a) there is a further sieve belt (5b) or two further sieve belts (5b, 5c), and within a lower sieve belt (5d), there is a further sieve belt (5e) or two further sieve belts (5e, 5f),

   wherein of the at least four sieve belts, at least two are arranged in active contact with the press material mat (2) in the area of the first zone (Z1), and of which at least two are arranged in active contact with the press material mat (2) in the area of the second zone (Z2), wherein the term active contact is also take to mean such contact when a further circulating sieve belt runs between the press material mat and the sieve belt, wherein the at least four sieve belts (5a-5f) each have their own drive (8).
2. Device according to claim 1, characterised in that provided in the first zone (Z1) is a device for applying steam (4a, 4b, 4c) to the press material mat (2), and at the end of the second zone (Z2) a device for air cooling (11) the press material mat.
3. Device according to any one of claims 1 to 2, characterised in that the device comprises a height-adjustable inlet (9).
4. Device according to claim 3, characterised in that a steam application device (4c) is arranged in the inlet (9) .
5. Device according to any one of claims 1 to 4, characterised in that the calibration plates are heatable plates.
6. Device according to any one of claims 1 to 5, characterised in that the first and the second zone (Z1, Z2) are arranged directly adjoining each other.
7. Device according to any one of claims 1 to 6, characterised in that arranged between two sieve belt defecting rollers (7) is a sliding block (13) bridging the gusset (12) between the sieve belt deflecting rollers (7) and the press material mat (2) and/or a sieve belt (5a, 5d).
8. Method of producing insulating or acoustic panels from a press material mat, that at least partially consists of lignocellulose particles coated with binding agents, with a device according to any one of claims 1 to 7, wherein at least four circulating sieve belts are used, of which at least two act on the press material mat (2) in the area of the first zone (Z1) and of which at least two act on the press material mat (2) in the area of the second zone (Z2),
   wherein the at least four sieve belts (5a-5f) are each driven by their own drive (8).
9. Method according to claim 8, characterised in that in the first zone (Z1), a device for applying steam (4a, 4b, 4c) applies steam to the press material mat (2) and at the end of the second zone (Z2), an air-cooling device (11) cools the press material mat (2).
10. Method according to any one of claims 8 to 9 characterised in that an inlet (9) is adapted by means of a device (10) to the ingoing press material mat (2).
11. Method according to any one of claims 8 to 10 characterised in that steam is applied to the press material mat (2) in the inlet (9).
12. Method according to any one of claims 8 to 11 characterised in that the first and the second zone (Z1, Z2) are arranged directly adjoining each other.
13. Method according to any one of claims 8 to 12 characterised in that the press material mat (2) is guided in the gusset (12) between two sieve belt deflecting rollers (7) over a bridging sliding block (13) .

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