SE452041B - Mineral wool prodn. - Google Patents

Abstract

The raw material is melted and passes to the rotating cylindrical body. It flows from the perimeter as fibres which are guided away from the plant by a gas stream. The fibres pass to moving collector surfaces which comprises two gas permeable surfaces through which gas passes to free the webs from the surface. Two or more mineral fibre webs are formed. They subsequently form an intermediate web which is folded to the desired thicknesses

Description

452 041 - 'too expensive, and in addition the fire properties of the products deteriorate. Too little binder results in poor mechanical properties, not least the elasticity. This is accentuated if the binder is placed so in the .minera] wool that it does not work properly.

As a result of extensive experimental work, the present invention has emerged as a solution to the problem of realizing a reasonably ideal structure in the mineral wool with high capacity and good for economical operation.

The production of mineral wool products usually takes place in a furnace, such as a dome furnace, where mineral raw materials such as diabase, limestone, slag, etc. are melted. The melt is continuously allowed to flow out of the furnace and into a fibrillation unit. The fibrillation unit can, for example, consist of a series of rapidly rotating cylinders of steel, against whose mantle surfaces the melt is carried. By rotation, the melt is gradually thrown out of the mantle surfaces, and fibers are formed. The fibers are primarily thrown out in a plane perpendicular to the axes of the steel cylinders. They are deflected from this plane by means of an air stream and carried by this air stream towards a collecting means, which may for instance consist of a net conveyor. The binder has as a rule been applied so that the deflected fiber stream is sprayed with a liquid binder so that the fibers and the binder are brought together towards the collecting means. During transport, some of the binder has hit fibers. Other binder droplets hit the fibers when they end up on the collection means. D As a rule, the collection has taken place in one step so that the desired_weight weight is formed on the collecting member. In other cases, a primary web has been formed, which is then converted into a final web with the desired basis weight by a folding procedure. The web with the desired basis weight has then been taken to a so-called curing oven, in which the product has been given the right thickness and the binder has been fixed by a heat treatment. This was followed by cooling, formatting and packaging. Different types of surface coating and other additional treatment occur in connection with mineral wool production.

The present invention relates to the part of a process for the production of mineral wool which lies between the fiberization itself and the finished web with the desired, final basis weight.

The collection surface for the mineral wool has usually been arranged at a fairly long distance from the fiberizing unit, for example 1-2 meters or even longer. During its airborne movement from the fibrillation assembly '452 041 to the collecting surface or collecting plane, the fibers swirl around in a rather uncontrolled motion and will occasionally hit each other. Then tufts and tufts of fibers are formed, which make it impossible to form the desired fiber structure in the mineral wool material.

The fibers will not be straight, in the plane of the product or at equal distances from each other. g It has previously been thought that this process was beneficial to the extent that it would provide good binder utilization. The idea has been that a binder drop would hit a fiber and stick to it. Thereafter, another fiber would strike the first fiber and slide along it until it reaches the binder drop, after which a semi-permanent, later permanent fixation, by the subsequent fixation, would occur.

However, a careful study of the process has shown that it does not work in this way. Many of the binder droplets found in the mineral wool products are in fact inactive and do not serve as a bond between two fibers.

Among the thoughts central to the invention is therefore an effort to avoid collisions fiber to fiber during transport between the fiberizing assembly and the collection surface, and to control the binder supply so that most binder droplets actually end up at intersections between the fibers. The realization of the invention then includes transporting the fibers from the fibrillation assembly to the collecting surface so that collisions are avoided. Thereby, fiber will be stored on the fiber-on-itself 'collection surface. The fiber orientation will then be parallel to the surface of the collection plane, and the fibers, which are almost straight from the beginning, will be stretched to their full length. Coincidence will of course give variations in the mutual fiber distance, but noticeable accumulations of fibers occur very rarely.

One of the possible means of effecting this dispersed transport of the fibers from the fibrillation assembly to the collecting surface or plane has been found to be to make the distance between them very short. Possibly others have previously been this thought on the tracks.

Thus, U.S. Patent No. 2,399,383 (Powell) discloses a device with an extremely short distance between the fiber wheel and the collection surface. However, such an arrangement can only do - in addition, it reports processes with unacceptably low capacity. 452. 041 very thin layers, and with the binder supply shown in the patent, the collection surface will very quickly become soiled at the same time as the binder will be very unevenly distributed in the product. It is also known that the process has never been applied. The American patent 2,450,9l6 (Coss) would have a somewhat greater precondition, since the process shows a folding operation with the aid of which even thick layers can be built up. Fl Here too, however, the binder supply is arranged so that it either gives heavy contamination of the collecting surface so that it quickly clogs and loses its function or, in the case of late application, means an uncontrolled and uneven binder application. The same is true of U.S. Patent 2,502,967 (Powell) and, to a greater extent, U.S. Patent 2,450,9l5 (Powell). All of the cited patents Dewsme folding devices have, as will be readily appreciated, a limited maximum D speed. This speed also determines the speed at which the primarily formed mineral wool web can be driven. In order to have a reasonable capacity, it must therefore mean that a primary mineral wool web with a high basis weight is manufactured. This becomes completely impossible to impregnate in the ways specified by the patents.

D These problems have also been brought to attention. For example, British Patent 772,628 discloses an arrangement (see Figure 21) which is very similar to the last of the above-cited U.S. patents.

The capacity problem has been solved here to some extent by doubling the equipment. However, the problem with impregnation remains. On the one hand, the system causes a rapid soiling of the collecting drums, and on the other hand, a relatively thin web is required so that the impregnation does not become hopelessly bad. Each of the two fibrillation units must therefore be operated at low capacity, which entails severe economic disadvantages.

Other process variants according to this British patent (see for example Figure 20) show a double-sided supply of binder to a freely conveyed mineral wool web. Due to the speed limitations in such a system, however, this also has an excessively limited capacity. Figure 18 of the patent shows a way to remedy this shortcoming by manufacturing several primary mineral wool webs in separate fiberizing and collecting plants in the same plant and then bringing them together in As mentioned above, however, this solution means that each fibrillation unit must be operated at low capacity.

In the light of the reported problem analysis and description of the prior art, the present invention is a process for the production of mineral wool products, in which the fibers are fixed to each other with a binder, so that a more or less dimensionally stable product is formed, and in which mineral raw materials are melted, and the melt is allowed to flow continuously against a fibrillation assembly, for example consisting of rapidly rotating cylindrical wheels, towards the periphery of which the melt is guided, and fibers are formed by ejection of the melt from this periphery, which fibers are removed from the fibrillation assembly and against a movable collecting surface. , through which the gas is diverted while leaving the fibers on the collection surface in the form of a continuously advancing primary mineral wool web; According to the invention, the collection is arranged to take place in such a way that fibers emitted from the fiberizing unit or from each fiberizing unit may simultaneously form and emit two or more primary mineral wool webs, which are collected separately, after which the primary mineral wool webs are later combined into an intermediate mineral wool web. which is formed by a folding process into a final mineral wool web with the desired basis weight, which is finalized in a manner known per se. The solution to the problem thus lies in the fact that the fibers emitted from a feeding assembly are collected into - not one but - two or several primary webs, which are emitted separately. Through the division into several primary webs, the basis weight of each web can thus be kept arbitrarily low at a given feed speed, without this in principle limiting. With current conditions, it has been shown that two capacities on the individual fiberizing unit may well be sufficient. separately delivered primary mineral wool webs. should hardly be relevant.

A transport of fibers from the fibrous member, which is moderately more than four primary webs turbulence-free, is more easily created if the distance is small, and it has been found that the distance should not exceed 800 and preferably not 400 mm.

As mentioned in the introduction, a binder is an important ingredient in most mineral wool products. The impregnation with binder now takes place most advantageously after the primary webs have been removed from the collecting surface but before they are combined before insertion into the folding device. _ ___... _..- _. .___ .. .. ~ _4s2 o4i_ The end agent is advantageously added to the primary web or webs, which entails a small risk of contamination of the collecting device, well-utilized binder and small losses. In order for the webs to be well impregnated, they must not be too thick. Suitably the basis weight is below 200 and preferably also below 100 g / m2. ' It is difficult to avoid that the side of a mineral wool web which is hit by the binder particles has a higher binder content than the opposite side.

It is therefore usually necessary to make the impregnation double-sided, ie expose both sides of the mineral wool web to the particle stream. If double-sided impregnation is used, ie the binder is applied to both sides of the primary web, the basis weight can be kept higher, which means higher capacity in a given plant. This means that the feed speed of the receiving surface must be so high that it with a given fiber flow falls below the specified limits. W It is important that the different primary paths are reasonably similar in terms of, for example, basis weight. The capacity ceiling is first reached by the primary web, which has the highest basis weight, and the second should consequently have a basis weight which is as close as possible to this maximum basis weight.

I I The supply of binder to the primary web or webs preferably takes place so that the webs are passed towards the mineral wool material directed, widespread streams of binder particles. Liquid binders are usually used, in which case the particles are droplets. However, mineral wool webs have also been successfully exposed to streams of finely divided, dry binder. The particles should have an incentive to penetrate the mineral wool web. This incentive can be the velocity and inertia of the particle. Even if binder is added to the preformed primary webs, it may be convenient to add a part, preferably a smaller part, of the binder already in connection with the fiberization and collection.

This gives the mineral wool web a certain basic impregnation, which means, among other things, that the requirement for low basis weight in the later impregnation of the primary webs can be mitigated. There is nothing to prevent the use of different binders in the two stages in such a two-stage impregnation. In fact, there should be a great advantage here, especially if one chooses a non-stick adhesive in the first step. Most mineral wool products must be equipped with something that eliminates or at least reduces dust emissions. Dust from 452 041 v. _ I w. _, x l mineral wool products can cause respiratory irritation. As a rule, a mineral oil is used as a dust-binding agent. This oil can be added at the same time as the binder and then usually distributed in this.

The distribution can only be mechanically achieved, but it also happens that dispersants of a chemical nature are used. In some cases, the combination of binder and oil is to be avoided, and it is then expedient to add oil in connection with fiberization and collection and to allow the binaeaaaiec to form the already formed web.

Mineral wool usually contains, in addition to fibers and binders, coarser particles of a more or less fibrous nature. These include so-called pearls, ie completely unfiber drops of solidified melt. There is reason to avoid excessive levels of these particles. One way of disposing of such particles from the mineral wool and possibly simultaneously introducing binder particles from the surface layer is to subject the mineral wool web or webs to the combination of a static, constant, downward force, e.g. the gravitational force or pressure of an air stream, and a dynamic force, preferably acoustic energy of such frequency and strength that particles on or in the webs are forced to travel in the direction of the constant force, whereby on the one hand undesired particles in the webs are removed and on the other hand desired particles from the upper surface layer are forced to penetrate into the interior of the mineral wool webs .

In the mineral wool industry, there has long been a need to add particles. These are particles that give the mineral wool new or improved properties. Such particles can consist of binders in dry form but also of particles which increase the ability of the mineral wool to prevent infrared radiation. In these cases, it is a matter of improving the mechanical properties and the insulating ability. However, one may also want to give the mineral wool new properties. A supply of this form of activated carbon 1 'finely divided form could give the mineral wool an absorption capacity for gases which it otherwise does not have. Such an absorbency would be valuable in some contexts when mineral wool is used as a filter. However, it has been very difficult to get such complementary particles to penetrate the mineral wool. the fiber structure of the inner wool with very small mutual fiber distances gives the same good filtering properties, something which in itself can be desirable in some cases, but which nevertheless prevents the penetration of powder. Attempts have then instead been made to add powder in connection with the fiberization, so that the powder and the fibers have at one time deposited into a powder-enriched structure. The disadvantage of such a process is the difficulty of spreading the powder so that the powder content of the mineral wool becomes fairly even. Furthermore, it has been very difficult to avoid losses of powder, which can be a significant disadvantage, since it is often a question of qualified materials to be added.

It has now surprisingly been found that both of these seemingly different problems can be solved by means of the above-mentioned new method, which means that the mineral wool is subjected to a constant force acting at an angle to the plane of the mineral wool and to a simultaneous oscillating energy, preferably acoustic energy.

The phenomenon that arises is very difficult to study in detail. It is believed that the acoustic energy causes such mutual movements of the powder and / or the mineral wool fibers that the powder, by means of the constant force, can move in relation to the fibers to an extent which far exceeds that previously observed.

This mobility of particles in relation to the fiber structure can now be utilized so that particles in the fiber structure are thereby caused to migrate out of it. It then turns out that the invention does have a limited effect on larger particles and deep-lying particles, but a sufficiently large effect on particles which are close to the surface of the mineral wool web. Therefore, by a method according to this method, the mineral wool material can be freed from the majority of the particles which could otherwise be shaken loose during handling, and which could cause skin irritation and give dark color to the wool and also use the method to obtain a powder, spread over the mineral wool web, to migrate into the mineral wool layer. Nothing prevents both phenomena_ from happening at the same time.

. As mentioned, gravity can be allowed to be the constant force, but it can also be exerted by an air flow which is generated, for example, by passing the mineral wool web over a suction box, in which a negative pressure prevails.

However, it has been shown that the combination of these two measures provides a constant force that can be dimensioned much more freely. By utilizing gravity for the entry of the powder and the exit of the particles, the process is also simplified in other respects. The discharged particles will then move away from the mineral wool web and it will be easy to initially apply the powder to the surface of the mineral wool web which is to be caused by the process to penetrate into the mineral wool web. As is readily appreciated, the process can be applied only in one direction. direction of constant force. Often, however, it is desired to remove particles from both surface layers of the mineral wool web, and it is then advantageous to apply the method first in one direction, then in the other. In this way, added powdered material can also be distributed more evenly in the mineral wool web than would otherwise be possible. "The frequency and intensity that the oscillating energy must have to give the greatest effect is largely dependent on the density, orientation and diameter of the fibrous material and the powder. the shape, size and density of the loose particles. To some extent, forces acting between the particles, such as adhesion, will also play a role. However, it has been observed that it can sometimes give a noticeably much better effect if you work with frequencies within two at the same time. distinctly spaced frequency ranges.In general, infrasound or very low frequency sounds prove to be appropriate.

The treatment which involves exposing the primary webs to a constant force and an acoustic energy should be applied before a liquid binder is applied.

The properties of the mineral wool products sought by the process are counteracted by the presence of melt splashes and unfiber particles. In particular, the risk of such 'contaminants' is high if the collection takes place close to the fiberisation unit. Measures should therefore be taken to avoid such contamination. An important part of these comes from disturbances in the melt jet which cause it to split or flutter. By ensuring that the melt jet is protected from external influences, especially particles ejected from the spinning wheels, a satisfactory purity in the mineral wool webs is achieved while at the same time losses of melt are avoided. The process according to the invention comes into its own if the folding process, in which the final web is formed, takes place in an orderly and well manner, and so that no undesired folds and other irregularities are formed.

Suitably this part of the process is then designed so that substantially all parts of the intermediate web are discharged directly over the places where they are to lie in the final web and at the same height above it. Thereupon i. I l l za 452 041 1.0 I develops displacements and pulls in the laid layers.

The invention will now be described with reference to a number of embodiments of plants for carrying out the method, which are shown in the accompanying drawings.

In the drawings, Figure 1 shows a side view of a schematic representation. device for producing mineral wool products in accordance with the invention. Figure 2 shows a detail of the device in Figure 1 on a larger scale. Figure 3 shows, in the same way as in Figure 2, a modified I device for collecting primary mineral fiber webs. Figure 4 shows a further modified device for simultaneous collection of two primary mineral fiber webs, and Figure 5 finally shows a detail of a device for simultaneous collection of three primary mineral fiber webs.

The plant shown in Figure 1 generally consists of a melting furnace 1, from which the melt is fed to a fibrillation assembly 2, and from there the formed fibers are transferred to a collecting plant 3. Via a transport plant the formed primary webs 4 are transferred to an impregnation plant 5 and from there via a folding device 6 to a receiving band 7.

From the melting furnace 1, the melt flows continuously over the melting groove 8 down on the spinning wheel 9. A gas stream coming from the left in the figure, for example an air stream, emitted from a blowing plant not shown in the figure, leads the formed fibers towards two perforated drums 11 and 12. The fibers 13 present in the air stream then deposit in the form of layers 14 and 15 on the respective drum. The two layers are removed and continued with conveyors 16 and 17 up to discharge positions 16 'and 17', from where they are lowered towards the impregnation plant 5.

This is arranged to double-sided apply binder particles to the primary webs through nozzles 21. These can be of several types.

Most advantageous, however, is the type in which liquid binder is ejected in the form of a flat jet from a plate, which rotates at high speed. The primary webs are kept stretched by means of the coanda devices 18 and 19. These consist of a curved surface, along which an air stream is blown.

The coanda devices fix the primary webs to a position close to the curved surface and at the same time exert a certain traction on them. Via an auxiliary conveyor belt 20, the primary webs are brought together in the folding device 21, which consists of two parallel conveyor belts 22 and 23. The upper part of the folding device 21 is movable upwards and downwards, and the lower part 24 is movable back and forth by means of a figure not shown guide system. The reciprocating movement - of the lower part of the folding device is provided by a cranking device 25 driven by a motor 26. The combined primary webs 14 and 15 are laid out on a conveyor belt 27 after leaving the folding device. The device for collecting the two primary webs is shown in Fig. 3 shows a device similar to that of Figure 2. The spinning wheel 28, which is supported by the spindle 29, which contains the shaft which drives the spinning wheel, receives melt from a melting chute not shown in the figure.

From the spinning wheel 28, particles are ejected into the radial plane. These particles give rise to fibers 30, which are discharged by a gas stream 31, for example an air stream, through the nozzle ring 32, leading the fibers in axial A direction towards the collecting device with collecting drum rolls 11 and 12. The particles which the air stream is unable to bend are ejected further. in the radial plane. The upwardly directed particles end up in the so-called bead trap 33, from where they are removed by means of a sharp conveyor (not shown in the figure). The particles thrown sideways and downwards end up in the catch pocket 34, from where they are removed with a screw conveyor 35.

The fibrillation and collection process takes place in a chamber with a rear wall 36, 37, a roof 38 and a bottom part 39. The bottom part seals by close connection to the lower drum 11.

On the lower drum 11 a fibrous layer 40 is collected, which is carried out in the space between the drums 11 and 12, past the sealing roller 41 and over to the conveyor 42. The wool layer is lifted from the drum 111 by means of a blow-off jet 43, which comes from a blowing ramp 44. The drum 11 is evacuated by means of a pipe system and a suction fan, which are not shown in the figure. The part of the surface of the drum over which the suction takes place is delimited by the seals 45 and 46, so that no suction occurs through the part facing away from the chamber. of the drum 47. The upper drum l2 is designed in a corresponding manner.

The sealing roller 48 connects to the roof 38 of the chamber by means of the lip 49.

Figure 4 shows a corresponding arrangement, but here an intermediate roller 52 is arranged between the two collecting drums 50 and B1.

The intermediate roller 52 rotates in the opposite direction to the two collecting drums 50 and 51. At point 53, the fibrous layer is pulled apart so that the portion lying on the intermediate roll 52 moves downward and is joined together with the layer formed on the lower drum 50 while the layer; lying on the upper drum 51 moves upwards and is fed dt under the sealing roller 54. Fig. 5 shows an arrangement of three collecting drums 56; 57, 58. In the engagement between the drum 56 and the drum 57 a intermediate drum 59 is placed , and in the engagement between the drums 57 and 58 a second intermediate roller 60 is placed. The drums 56-58 rotate in the same direction as the arrows show, and the peripheral velocities are the same on all the drums and rollers 56-60. The figure shows how the three collecting drums 56, 57 and 58 are evacuated through their respective suction line beer, 62 and 63. These lines run together in a larger channel 64, which leads in the direction of the arrow to one or more suction fans. With the aid of the dampers 65, 66 and 67, the evacuation intensity in the drums is regulated and thus also the amount of fibers with which each drum is coated. If, for example, it turns out that the middle collecting drum 57 absorbs more fibers from the fibrillation assembly than the other two drums, the evacuation line 62 is throttled with the damper 66 or the dampers 65 and 67 are opened to increase the suction from the outer collecting drums 56 and 58.

Claims (21)

i 452 04,1 13 'P a t e n t k r a v A process for the production of mineral wool products, in which the fibers are fixed to each other with a binder, so that a more or less dimensionally stable product is formed, and in which a mineral raw material is melted and allowed to flow continuously against one or more fibrillation assemblies (2) , consisting of rapidly rotating cylindrical wheels (9h against the periphery of which the melt is allowed to flow, forming fibers (13) which are carried away by a gas stream from the fibrillation assembly (2) and against a movable collecting surface (3) consisting of one or more movable gas permeable surfaces, through which the gas is diverted while leaving the fibers on the collection surface in the form of one or more continuously advancing mineral fiber webs, characterized in that the fibers emitted from the fibrillation assembly (2) or each fibrillation aggregate are simultaneously collected into two or more primary fibers. (4), which are collected separately, wherein from the fibrillation assembly (2) or each fibrillation aggregate a stream of mineral fibers (13) suspended in a gas, e.g. air, is taken, which fiber stream is divided, preferably by horizontal divisions, in a flow for each of the primary mineral fiber webs to be formed, and is led to a collecting surface (3 ) for each of these flows,. and in that the primary mineral fiber webs (4) are at a later stage combined into an intermediate mineral fiber web, which is formed by a folding process into a final mineral fiber web of the desired thickness, which is finalized in a manner known per se. A method according to claim 1, characterized in that the primary mineral fiber webs (4) are impregnated (5), preferably double-sided, with a binder before they are joined to the intermediate web, and in that the mineral fiber web finally formed after folding is heat-treated. and cooled and divided into desired pieces. 452 041. ' A method according to claim 1 or 2 ,. characterized by the division of the flow by means of special dividing means (52; 59, 60) between the different collecting surfaces (50, 51; 56-58L A method according to any one of the preceding claims, characterized in that the formed primary mineral fiber webs are removed at such a rate that they have basis weights less than 200 g / m 2 or preferably less than 100 g / m 2. ~ 5. A method according to claims 2-4, characterized in that the impregnation takes place during free movement of the mineral fiber webs. Method according to one of the preceding claims, characterized in that oil is supplied to the mineral fibers separately and in connection with the supply of the binder, in which case it is preferably distributed in the binder. . Method according to one of Claims 2 to 6, characterized in that the primary mineral fiber webs (4) are subjected to a constant force directed at an angle to the webs, for example gravity, in combination with acoustic energy of such frequency and strength that particles on or in the webs are forced to migrate »into the mineral fiber webs in the direction of the constant force. 8. A method according to claim 7, characterized in that a particulate material, for example a finely divided dry binder, is supplied and introduced into the mineral fiber webs. 9. A method according to claims 7 and 8, characterized in that the constant force is at least partially exerted by an air stream which is forced through the mineral fiber webs. 10. A method according to claims 7-9, characterized in that the treatment takes place on both sides. Method according to claims 7-10, characterized in that the treatment takes place before impregnation of the primary mineral fiber webs. I 1 - Method according to one of the preceding claims, characterized in that the collection of the mineral fibers into primary mineral fiber webs (4) takes place at a distance from the fiberizing assembly (2) or assemblies of less than 800 mm and preferably less than 400 mm. 13. ' Method according to one of the preceding claims, characterized in that the folding process is carried out in such a way that substantially all parts of the intermediate web are discharged directly above the places where they are to lie in the final web and at the same height above them. Device for carrying out the method according to any one of the preceding patent claims consisting of one or more fibrillation assemblies (2) arranged to be supplied with a mineral melt to form a stream of mineral fibers (13), which after collection and processing form a final mineral fiber mat of desired thickness, characterized in that the device comprises means (3) for simultaneously forming from the fibrillation assembly (2) or each fibrillation aggregate two or more thin, primary mineral fiber webs (4) by preferably horizontal division of one from the fibrillation assembly (2) or each fiberizing aggregate drawn stream of mineral fibers (13) suspended in a gas, eg air, means (20, 22, 23) for joining the primary mineral fiber webs (4) to an intermediate mineral fiber web, and means (6) for forming by a folding process the intermediate mineral fiber web to a final mineral fiber mat of the desired size and thickness. IN Device according to claim 14, characterized in that the means for forming the primary mineral fiber webs (4) consist of perforated sheet metal drums (11, 12; 50, 51; 56-58) with horizontal axes or the like, through which against the fiberizing assemblies or the units (2) facing the fiber-bearing gas are forced, the drums (11, 12; 50, 51; 56-58) being mounted one above the other at a short distance from each other and arranged to rotate in the same direction and at the same peripheral speed and preferably cooperating with one or more smaller, perforated rollers (52; 59, 60) in the middle of each space between the drums (50, 51; 56-58) on the side where the fiberization takes place, which rollers (52; 59, 60) are arranged to rotate towards opposite direction but with the same peripheral velocity as the drums (50, 51; 56-58% Device according to claim 15, characterized in that it contains two perforated sheet metal drums (50, 51) and an intermediate roller (52). Device according to claim 15, characterized in that it contains three or more perforated sheet metal drums (56-58) and in the gaps between each pair of drums a fiber-distributing intermediate roller (59, 60). 18. A device according to any one of claims 15 or 16, characterized in that at least the lower (11; 50) of the metal drums (11, 12; 50, 51) are connected to means for creating a negative pressure in the drum resp. the drums, which causes flow and evacuation of the gas carrying the mineral fibers (13) from the fibrillation assembly or assemblies (2) to the drums (11, 12; 50, 51l). Device according to claim 18, characterized in that it contains four drums (11, 12; 50, 51; 56-58), and in that it is designed with means for individual regulation of the negative pressure in the different drums. ' Device according to claim 16 or 17, characterized in that the pile drums (11, 12; 50; 51; 56-58) with the meilan roller or the meienvaïs (52; 59, 60) are mounted at a collecting distance. from the fibrillation assembly (2) or the aggregates of less than 800 mm and preferably less than 400 mm. ~ 21. 2l. Device according to one of Claims 14 to 20, characterized in that the removal of the primary mineral fiber webs (4) and the joining thereof to the intermediate web take place with the aid of coanda devices (18, 19), which primary minera1fiber ~ webs stretched.during the fusion.