NO134461B - - Google Patents

Description

Mineral wool is produced in such a way that, in a spinning machine, the formation of fine fibers of molten mineral, e.g. glass, stone, slag etc., which are thrown out by a fan towards a traveling belt, on which the fibers are collected. On the way from the spinning machine to the belt or possibly on the belt itself, the fibers are sprayed with various liquid products. Occasionally, an oil is added to bind lint produced during spinning and to give the fibers hydrophobic properties, and as a rule a binding agent is added, designed to fix the fiber mass into a certain shape. The binder is usually of the plastic type and acts so that the fibers are fixed to each other at the points of contact. The binder is stabilized by heat treatment. The purpose of the heat treatment is, by evaporation, to remove any water present, to harden the binder, if it consists of a thermosetting plastic or to melt it if it consists of a thermoplastic.

During the course from the spinning machine to the belt, the fibers form loops and bends, and when these fall onto the belt, they store

itself with the plane of the bay or sloyf completely or more or less almost parallel to the plane of the band. Thereby, a strongly pronounced layer formation occurs in the manufactured mineral wool mat, which leads to this becoming very compressible in a direction perpendicular to its own plane but significantly much less compressible in all different directions that fall parallel to the plane of the mineral wool mat.

For several purposes this characteristic may be desirable and useful, but for other purposes it is decidedly harmful. As an example of a case where the compressibility is harmful, the use of the mineral wool mat as insulation around rudders, cisterns and the like, which contain media whose temperature differs significantly from the surroundings, can be mentioned. When wrapping a mineral wool mat of the type specified above around e.g. a rudder, namely the outer layers are pulled together in the peripheral direction, which leads to compression of the material and reduced insulation effect. Another example is the application as insulation in floors and joists, where it must be possible to load the mineral wool mat in a direction perpendicular to its plane without it being pressed together. When placing a mineral wool mat in a joist layer for thermal insulation thereof, whereby the mat can be loaded with a force that acts perpendicular to its plane, it is likewise pressed together and becomes less thick but increases in density. The mineral wool mat thereby has less insulating capacity due to its reduced thickness, but at the same time the specific insulation figure increases slightly due to the increase in density.

Many other examples could be cited. With full clarity regarding these conditions, it has already been proposed to alternately cut open the mineral wool mat from one side and from the other, with part of the mineral wool mat remaining in an uncut state, and then to fold the mineral wool mat alternately in one and the other direction about the remaining , not re-cut parts, so that the mineral wool mat assumes a zigzag shape. However, this known method leads to a certain resilience occurring at each folding point, and this resilience in turn leads to a tendency to create longitudinal cavities at the folding points, so that the mat will not hang together well. It has already been proposed, after the mineral wool mat has hardened, to divide it into separate strips, which have been turned 90° around their own longitudinal axis and then joined together, so that what is called a lamellar product has been obtained. Instead of turning the strips 90° about the longitudinal axis, they can be reoriented in another way with the same effect. The joining has usually taken place simultaneously in two different ways or at least in each individual case in one of the two different ways. One has thus either glued the underside of the slats to a substrate, e.g. a layer of kraft paper or a suitable wood fiber board and/or you have glued together the opposite sides of the mineral wool slats into a flat formation.

The aforementioned gluing methods require costs and work and thereby make the manufactured product more expensive. The types of glue in question are usually flammable, and thus a flammable material has been inserted into the non-flammable material that forms the effective mass of the mineral wool mat, which increases the flammability of the mineral wool mat. If paper is used, this is also flammable.

The present invention primarily aims to avoid the gluing process according to the method used until now when producing laminated mineral wool mats or sheets. The invention is based on an observation, namely that it is advantageous, by observing certain special precautions, to provide a laminated consistency of the mineral wool mat already before it has been hardened. If one turns on edge or otherwise reorients the separated strips and presses them against each other, for the resulting mineral wool mat is inserted into the curing section, the added binder, usually a curable plastic, serves as a binder simultaneously between the fibers in the interior of the strips and between the strips, and you get a continuous mineral wool mat, where the fibers are oriented largely across the plane of the mat and without the need to add either glue or paper. If, however, the strips were to be brought together in the facing position in the direction of the curing apparatus without each individual strip in the package being under the pressure produced by compression, the strips could be separated from each other, they would be able to assume a sideways bent formation, and cohesion within the package could be largely lost. The invention therefore also relates to maintaining the pressure in the strips in the direction of the plane of the remaining package during its entire path to the curing apparatus.

The invention thus relates to a method for producing mats or sheets of cross-laminated mineral wool starting from spun and at least fixative-impregnated mineral wool in the form of a continuously running mat. The formed mat is divided into completely separate strips, and these are reoriented by turning by twisting. They lie tla parallel and next to each other, twisted at least by 90° about the longitudinal axis, so that they lie with their cut surfaces in the same plane, after which they are arranged in a parallel course closely

next to each other in such a direction that they will lie side by side.

According to the invention, the division of the mat into strips takes place for the curing of the fixing agent, but after the mat has been compressed, and the reorientation of the strips only takes place afterwards. In the reoriented position, the strips are fed to a device for curing the fixing agent, so that this will simultaneously serve as a binding agent between the individual fibers and as a binding agent between the strips. The strips are fed by twisting between pairs of cooperating conveyor belts, arranged to receive each strip from the dividing device and to twist it by at least substantially 90° and to transfer the strips to mutually parallel

positions next to each other until the curing device.

With this method, one achieves the great advantage that the strips are under continuous compression, so that in the interior of the individual strip no reorientation of the fibers can

take place beyond that which has occurred during the compression, and this ! compression is maintained until the case, when the strips pass through the curing apparatus, so that simultaneous bonding in it

easing off the strips and between the strips takes place.

The invention will be described in more detail below in connection with an embodiment shown in the drawings. It is understood, however, that the invention is not limited to this particular embodiment, as many different modifications of this can occur within the scope of the invention.

In the drawings, fig. 1 a schematic diagram of a device for the production of transversely oriented mineral wool according to the present invention, while fig. 2 shows a schematic detailed sketch of the spinning apparatus.

Fig. 3 shows a corresponding sketch of the dividing and turning apparatus,

and fig. 4 shows a corresponding sketch of the curing apparatus in a plant according to fig. 1.

In fig. 1 is a cupola furnace for melting the mineral designated 10. A jet of mineral melt 11 flows down towards the spinning device, which in this case is shown with only one spinning hole 12, although as a rule several spinning wheels arranged in cascade one after the other would be more expedient. The spinning wheels which thus in fig. 1 is represented by the wheel 12, rotates at high speed, and due to the centrifugal force the tough mineral melt is ejected in the form of fine threads 13. These are sprayed, e.g. on its way towards the collection device with a dissolution of a plastic, which when heated leads to evaporation of the solvent and thereby binds together the individual mineral fibers at their crossing points. The plastic shower is fed using a nozzle 14.

Impregnated in this way with a constantly liquid plastic solution, the mineral wool reaches a band 15, on which it is deposited under the influence of a fan 16, which sucks air through the band 15 into a suction box 17. The band is preferably laid out as an endless band, which moves over two rollers 18, 19, one of which is motor-driven (not shown in the drawing). A loose accumulation of strongly layered mineral wool is thereby stored on the belt in the form of a mat 20, which can suitably be compressed by pressure from a press roller 21. In a possibly compressed, not yet hardened and highly elastic state, the mineral wool mat passes out in the form of the mat 22.

Immediately after the mat has left the belt 15, it arrives

into the area of the dividing organs 23. These are shown in the form of saws. Several such saws are arranged next to each other, so that they hide each other, and consequently only one such saw is seen in fig. 1. The division does not of course need to take place in a plane, which is achieved with the help of saws 23. However, the mat is divided in this way into a number of strips, which travel into a turning device. This consists for each strip of two emitting rollers 24, 25, which are arranged with horizontal axes, and two receiving rollers 26 and 27, which are arranged with vertical axes. An endless belt 28 runs over the rollers 24 and 26, while a second endless belt 29 runs over the rollers 25 and 27. These belts 28 and 29 will thus between them catch the mineral wool strip and turn it by the twisting that the belts undergo on their way from the rollers 24, 25 to rollers 26, 27.

If compression of the strips has been carried out, retain these

during their movement between the belts 28, 29 constantly this compression, which is imparted to them by means of the roller 21, but they have a tendency to expand elastically in a direction which on the belt conveyor 15 acted vertically, but which due to the turning of the strip between the bands 28, 29 on a conveyor 30 following the rollers 26, 27 will act horizontally. Thereby, the adjacent strips are pressed against each other,

when, by means of the endless conveyor 30 moving over the rollers 31, 32, they are fed through an oven 33, in which the hardening of the plastic material sprayed on by the nozzle 14 takes place, e.g. by blowing through with hot gas. In the past, it was common to harden the plastic immediately after the mineral wool had passed the band 15, but in the present case, the hardening thus takes place only after division into strips and their turning.

It is previously known to spray on a plastic solution in a way that takes place with the help of the nozzle 14. You can then use this plastic solution as a binding agent after curing in the oven 33 not only in the manner known per se to bind together

but the fibers at the crossing points in each strip, but also on

connect the individual, mutually adjacent strips to each other in the above-mentioned manner. This ratio has already previously been used in connection with folded mineral wool. On the other hand, it is not known in the same way to join together loosely cut strips of mineral wool, which have been individually twisted in the above-mentioned manner. The invention is based on the observation that this is possible.

At the outlet side of the oven 33, a transversely continuous, continuous, cross-laminated mineral wool mat 34 appears. This is then cut using a knife, a saw, etc. 35

in customized lengths 36.

A cutting of the mineral wool mat into strips thus already takes place before curing, and after the cutting, the strips are arranged in a mutually cross-laminated position. When they are then hardened, in the same way as when the hardening took place immediately after the band 15, a bond occurs between the individual fibers occurring in each strip at their crossing points, but in addition to this, in the method according to the invention, a bond also occurs between a vertical plane on a strip and against this vertical plane under pressure the adjacent vertical plane of the adjacent strip.

It is now assumed that one knows how a spinning apparatus for the production of mineral wool is arranged. An example of such a spinning apparatus is thus schematically shown in fig. 1, containing the spinning wheel 12, but it is obvious that the invention is not limited to the use of just such a spinning apparatus, since any spinning apparatus can be used for the purpose of the invention.

Fig. 2 shows an example of how compression of the formed, from the beginning very loose mineral wool mat can take place to provide the expansion tendency which may be appropriate for, in a later phase, providing the pressure between the different strips, which are to be attached to each other for formation of the finally cross-laminated mineral wool mat.

As can be seen from the above, the strips can theoretically be cut to any angle to the longitudinal direction of the mat. For practical reasons, however, it will only happen that they are cut either across or along the length of the mat. Even if in the embodiment shown below the latter turns out to be the ratio, the invention shall not be limited to this.

The loose mineral wool 20 is transported in the direction of the arrow 37 by the endless belt 15, which runs over the roller 19. In fig. 1, the device for providing compression in the form of a roller 21 was schematically shown. The more complete device for this purpose consists of a second endless band 38, which runs over the rollers 39, 40 and 41, as a further roller 42 can be arranged to press down the upper lap of the band. The mat, which in its loose state 20 has the thickness shown on the left in fig. 2, is compressed in this way to a smaller thickness, but greater density, as shown at 22 to the right in the same figure.

Immediately after the roller 41, where the endless conveyor belt 38 faces, a set of saw blades 43 is arranged. It is of no decisive importance to the invention how these saw blades are arranged, if only their sawing direction is such that the compressed mat 22 is sawn into strips. These strips can thus e.g. go across the mat's lengthwise direction, but with the one shown

design, they run in the lengthwise direction of the mat. They are indicated at 44. By the line in the interior of the strips, the layering direction in them is indicated. In order to get a cross-laminated mineral wool mat from them, they must be turned 90° around their own longitudinal axis, so that e.g. the side as in fig. 2 is denoted by 45, forms the underside. This takes place in the device according to fig. 3,

which is intended to follow immediately after the device according to fig. 2, as also appears from fig. 1.

In fig. 3, for the sake of overview, only the mechanical equipment is shown, and this is even shown fragmentarily. However, the person skilled in the art will immediately understand what it looks like in complete condition. A motor 46 is provided for by means of a belt 47

to drive two rollers 48 and 49. For steering the belt 47 is also

a pair of additional auxiliary rollers 50 and 51 provided. Above each of the rollers 48 and 49 runs a set of endless conveyor belts, of which only the conveyor belts 52 and 53 is shown. These two conveyor belts are arranged so that between them they occupy the strip 44, see fig. 2. They are twisted, as rollers 48 and 49 run horizontally, while rollers 54 and 55 are vertical. The consequence is, as one can easily see, that the strip between the two belts 5 2 and 53 will be turned on its edge, so that its layer direction will be vertical, when it leaves the belts 5 2 and 53 at the rollers 54 and 55.

When the device is in operation, a larger number of such transversely oriented strips in width will thus be advanced past the rollers 54 and 55 resp. those with these parallel arranged rollers. They are thereby fed into the device shown in fig. 4. In this figure, you can find the two endless belts 5 2 and 53, which run over the rollers 54 and 54 respectively. 55. The entire package of such transversely oriented strips is taken up at the transition to the device according to fig. 4 between a pair of endless conveyor belts 56, 57, which run over the rollers 58 resp. 59, like a pair in fig. 4 not visible rollers at the opposite, to the right of the drawing not shown bays of the endless bands 56, 57.

It should now be noted that the strips have not yet hardened. After they have been compressed, they have retained their full elastic return force in relation to the compression to which they were possibly subjected in the device according to fig. 2 under the influence of the band 38, and they therefore seek to expand again. During this expansion, they are pressed in a horizontal direction against each other, so that in many cases a desirable contact pressure is obtained between them so that when they pass through the curing apparatus 33 they will stick well to each other, without the need to add glue and without it being necessary to line them with paper, woven fabric etc. material.

As a rule, the friction between the pack of strips on the one hand, and the bands 56, 57 on the other side, will not be sufficient to advance the pack of strips in a truly parallel movement. The bands 56, 57 are primarily intended to create a counter pressure against the expansion pressure from the strips. For that reason, in the device according to fig. 4 also a number, in the drawing two further endless belts 61 and 62 arranged to run around a horizontal roller 63 running perpendicular to the feed direction corresponding to the roller 31 in fig. 1, as well as a further turning shaft, which, however, is not visible in fig. 4, as it would fall to the right of the image surface, but which is shown at 32 in fig. 1. Between the bands 61 and 62 and on each side of these, smooth table tracks 64, 65 can be arranged, on which the package of cross-laminated strips runs on its way into the curing oven 33.

From the curing oven 33, the package then flows out with a bandage provided by curing it at the shower device 14, fig. 1, added plastic dissolution, partly in an already well-known way between the individual fibers in the mineral wool mat, especially at their crossing points, partly also between the vertical long sides of the strips.

In that the sawing of the mineral wool mat, fig. 2, occurred in the longitudinal direction of the mineral wool mat, the strips will run in the longitudinal direction of the entire mechanical equipment, figuratively speaking with infinite length, which in reality is only limited by the interruptions that inevitably occur when the machine is stopped for cleaning, service or cessation of work for other reasons . This is of course a great advantage, as it is thereby possible with a kappean arrangement, which, however, does not form any part of the present invention, but which is shown at 35 in fig. 1, to cut mineral wool mats into pieces 36 of the desired length. In addition, there can of course also be a side cutting device, which cuts off the possibly somewhat uneven edges of the mineral wool mat. However, the invention is in no way limited to this embodiment, although it has significant advantages. One can thus also, in cases where this is considered more advantageous for one reason or another, let the saws or the cutting members 43, see fig. 2, work in a direction across the longitudinal direction of the mat or otherwise in any appropriate direction, and one then only has to ensure that the produced strips are transported in a suitable way away from the sawing device to then be processed in the manner described above in connection with the one in the drawings

shown embodiment.

in

It is now obvious that the invention is not limited to the production of such planar formations of cross-laminated mineral wool, which are not provided with cladding. The manufacturing process itself according to the above offers in itself such great advantages that it is well suited for adaptation even if one wants to cover the mineral wool mat with an appropriate material known in and of itself, e.g. kraft paper. A particularly advantageous material is glass fiber cloth, which is not flammable but has greater tensile strength in all directions than paper. You can of course also attach the formed mineral wool mat to another substrate, e.g. a plywood sheet, fiberboard, etc.

The strength of the formed connection between the strips is, as will be understood from the above, dependent on several different circumstances. On the condition that the concentration of the plastic solution used and the chemical nature of the plastic are appropriately balanced, the amount of plastic solution sprayed on naturally affects this, but to a particularly high degree it has been shown that the strength depends on the elastic force with which the strips are attached or pressed towards each other during the passage of the apparatus shown in fig. 4. This elastic force can again depend on the degree of compression in the device, which is shown in fig. 2. In practical tests, it has been found that a compression of essentially 50%, i.e. such a compression that the thickness of the mat is reduced to approximately half of its original thickness is fully sufficient, that a weaker compression under certain circumstances can lead to a deteriorated connection , and that a significantly stronger compression is practically of no value for the goodness of the dressing. On the other hand, stronger compression can give the manufactured product other advantageous properties.

The stability of the manufactured cross-laminated mineral wool mat can be further improved by feeding in a reinforcement or reinforcement layer for the cutting into strips under and/or above the mineral wool mat, which of course should preferably be of a non-combustible material and can consist of glass fiber cloth. This or these layers will then be split up in connection with the formation of the strips, and they will follow with the mineral wool strips so that they are stored in a vertical direction at the joining rafts between the strips, where in the finished product they serve as extremely good reinforcements.

It is common for certain special purposes to provide a mineral wool mat, then also such a mineral wool mat where the mineral wool is transversely oriented, with a surface layer. Also in the present case, of course, such a surface layer can be

given after the joining of the strips, whereby the transversely oriented mineral wool mat is formed. The surface layer can be applied

on one side or on both sides. The surface layer or the surface layers can consist of a mineral wool layer, which is separated from the originally present web for dividing it into strips. It is of course also possible to apply a surface layer to the mineral wool web both before its division and after joining.

In fig. 4 is shown as an example of this supply of such a layer

67 around the roller 63. This thin layer can consist of mineral wool,

which has been cut in advance from the same mineral wool web 22 or from another mineral wool web, but it can also consist of paper, glass fiber cloth, wood fiber board or other suitable product. Such a surface layer can be placed not only on the underside or the top of the formed formation, but also, if desired, on both sides thereof. When passing through the curing oven 33

attach this or these layers to the produced laminated product.

Claims (16)

1. Method for the production of mats or plates (34, 36) of transversely oriented mineral wool starting from spun and at least fixative-impregnated mineral wool in the form of a continuously running mat (20), the formed mat being split into strips, and these are reoriented by being turned by twisting and then lying parallel and next to each other, twisted at least by 90° about their longitudinal axis, so that they lie with their cut surfaces in the same plane, after which they are arranged in a parallel course close to each other in such a direction that they will lie side by side, characterized in that the division of the mat (22) into strips (44) takes place before the curing of the fixing agent but after the mat has been compressed, and that the reorientation of the strips (44) only takes place after the compression, as the originally present mineral wool mat (20) is thereby exposed to strong compression for its division and for the reorientation of the strips side by side in relation to each other, that the strips will be pressed against each other by this compression; that the strips (44) in a reoriented position are supplied to an apparatus for curing the fixing agent, so that this will simultaneously serve as a binding agent between the individual fibers and as a binding agent between the strips; and that the mat (22) resp. the strips (44) on their way from the place of compression (21) to the place of hardening of the binder (33) are kept continuously under pressure in such a direction that the compression is maintained. 2. Method as stated in claim 1, characterized in that the mat (22) is divided into strips (44) which run in the original longitudinal direction of the mat (22). 3. Method as specified in claim 1 or 2, characterized in that a surface layer is placed under and/or above the mat (22) for its division into strips (44). 4. Method as stated in claim 3, characterized in that a surface layer consisting of a non-combustible material is inserted, e.g. fiberglass cloth. 5. Method as stated in any of the preceding claims, characterized in that the mat (22) is compressed to roughly half or less of its original thickness (20). 6. Method as stated in any of the preceding claims, characterized in that a surface layer is applied to one or both sides of the mineral wool mat formed of transversely oriented mineral wool. 7. Method as stated in claim 6, characterized in that a mineral wool layer is used as the applied surface layer, which has been separated from the originally present mineral wool web for its division into strips. 8. Method as stated in any of the preceding claims, characterized in that after the mineral wool (22) has been divided into strips and their turning, but for their hardening, a surface layer (26) is applied, e.g. consisting of mineral wool, on the underside and/or the upper side of the formed laminated product. 9. Device for carrying out the method as specified in any of the preceding claims for the production of mats or plates of transversely oriented mineral wool starting from spun and at least fixative-impregnated mineral wool in the form of a continuous mat, characterized in that the device in now mentioned sequence contains an organ for advancing the mat (22) in the form of a web of mineral wool (22) not yet divided into strips (44) over a running belt under a compression device (21) for compressing the mat to a reduced thickness (22) , a dividing device (23) for the division of the mineral wool mat (22) into strips (44), a turning device (24 - 29) for twisting the strips (44) formed by the splitting at least substantially 90° around themselves longitudinal axis, a device (56, 57) for joining these strips (44) side by side, as well as a hardening device (33) for the impregnating agent; that the mineral wool remains without hardening of the binder until the strips (44) are introduced into the hardening device (33); and that the device also contains means for exerting pressure against the mat or the strips in such a direction that the compression is maintained, which means are active from the place of compression (21) to the place of hardening of the binder (33). 10. Device as stated in claim 9, characterized in that the dividing device consists of a sawing body (23), arranged to divide the mat (22) into strips (44). 11. Device as stated in claim 9 or 10, characterized in that pairs of cooperating conveyor belts (53, 54) are arranged to receive each strip (44) from the dividing device (23) and during screwing with at least roughly 90° to transfer the strips (44) into mutually parallel positions next to each other. 12. Device as stated in claims 9-11, characterized in that the package of mutually parallel strips (44) is arranged to be caught between a pair of running bands (56, 57), which are arranged to attack this package from the edges for maintaining pressure in the package's direction of travel, parallel to its plane. 13. Device as stated in claim 12, characterized in that the running bands are arranged as endless bands (56, 57). 14. Device as stated in claim 12 or 13, characterized in that further belts (61, 62) are arranged to carry the package of strips (44), preferably in the form of endless belts, which reverse the direction of movement around horizontal rollers (63, 32 ). 15. Device as stated in claim 14, characterized in that smooth sliding tables (64, 65) are arranged between the latter bands (61, 62). 16. Device as stated in any of the claims 12 - 15, characterized in that the conveyor belts (56, 57, 61, 62) for the package of strips (44) are arranged to feed this package into a curing oven (33) designed curing device for curing the impregnating agent.