SE452040B - Mineral wool prods. mfr. - Google Patents

Abstract

The molten mineral material flows to the plant which comprises a fast rotating cylindrical body. Fibres are thrown out and are guided by a gas stream to a moving collector surface which is gas permeable. Air currents remove fibre webs in such a way that the wet weight/area is reduced. Subsequently the web speed can be reduced so that the weight per unit area can be increased up to more than double. The web is then folded, heat treated, cooled and divided up into the required pieces.

Description

452 uno too expensive, and in addition the fire properties of the products deteriorate. -Too little binder causes poor mechanical properties, not least in terms of elasticity. This is accentuated if the binder is placed so that the mineral wool 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 manufacturing economy. . l in g 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 allowed to flow continuously out of the furnace _and into a fibrillation unit. The fibrillation assembly may, 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 droplet droplets hit the fibers as they end up on the collection means.

As a rule, the collection has taken place in one step so that the desired basis weight is formed on the collecting means. In other cases, a primary web has been formed, which is then converted by a folding procedure to a final web with the desired basis weight. 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 oao k to the collecting surface or collecting plane, the fibers swirl around in a rather uncontrolled movement 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 fiber material. 1 The fibers will not lie straight, in the plane of the product or at equal distances from each other. 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 drop of binder 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 permanently fixed by the subsequent fixation, connection 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 fiber products are in fact inactive and do not serve as a bond between two fibers.

Among the ideas central to the invention, therefore, is an effort to avoid fiber-to-fiber collisions 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 fiberizing assembly to the collecting surface so that collisions are avoided. Thereby, fiber will be stored on fiber on the collecting surface itself. 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 an extremely short distance device between the fiber wheel and the collection surface. However, such an arrangement can only make 452,040 E of very thin layers, and with the binder supply shown in the patent, the suture surface will be soiled very quickly while the binder will be very unevenly distributed in the product. It is also known that the process has never been applied. p ',.

The American patent 2,450,9l6 (Coss) would have a somewhat greater condition, since the process shows a folding operation with the aid of which even thick layers can be built up. Even 'here', however, the binder supply is so arranged that it either gives "heavy soiling of the collecting surface so that it quickly clogs and loses its function or, in the late application option, means an uncontrolled and uneven binder application. The same applies in U.S. patent 2 D2,967 (Powell) and, in particular, U.S. Patent 2,45D, 915 (Powell). All of the patents cited also disclose the process with unacceptably low capacity. The folding devices shown are readily apparent. A limited maximum speed. This speed also determines the speed at which the primary formed mineral fiber web can be driven. In order to have a reasonable capacity, it must therefore mean that a primary mineral fiber web with a high basis weight must be manufactured. This becomes completely impossible to impregnate on. manner specified by the patent. '.

These problems have also been highlighted. For example, British Patent 772,628 shows an arrangement (see Figure 21), which is very similar to the last of the American patents cited above.

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

Theoretically, the collecting means could also be operated at high speed, but this is not possible in view of how the formed mineral fiber web is expected to behave later in the process.

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 fiber web. However, due to the speed limitations of such a system, this also has an excessively limited capacity. Figure 452 040 18 of the patent shows a way to remedy this shortcoming by manufacturing several primary mineral fiber webs in separate fibrillation and collection plants in the same plant and then assembling them in a folding procedure. As pointed out above, however, this solution means that each fiber assembly 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 fiber products, in particular those in which the fibers are fixed to each other with a binder, so that a more or less dimensionally stable product is formed, and wherein 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 directed, and fibers are formed by forcing the melt from this periphery, which fibers of a gas stream are removed from the fibrillation assembly. and against a movable collecting surface, through which the gas is diverted while leaving the fibers on the collecting surface in the form of one or more continuously advancing primary mineral fiber webs. The method according to this invention means: - that the formed primary webs or webs are removed in a first step - removed by such a speed that the basis weight becomes low; that the speed of the primary web (s) is reduced in a later stage so that a new, intermediate web is formed, the basis weight of which is greater than, preferably twice as large as, the total basis weight of the primary web or primary tracks; During a folding procedure, a final web is built up by the intermediate web, after which it is heat-treated, cooled and divided into the desired pieces in a manner known per se.

As mentioned at the outset, a binder is an important ingredient in most mineral fiber products. The binder is advantageously added to the primary web or webs, which entails little 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. A transport of fibers from the fiberizing unit, which is relatively 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. ... aëfa 452 040 The supply of binder to the primary web or webs takes place suitably so that the webs pass past the mineral fiber material directed, widespread streams of binder particles. Liquid binders are usually used, in which case the particles are droplets. However, mineral fiber webs have also been successfully exposed to streams of finely divided, dry binder. The particles should have an incentive to penetrate the mineral fiber web. This incentive can be the particle velocity I and inertia.

It is difficult to avoid that the side of a mineral fiber web which is hit by the binder particles has a higher binder content than the opposite side. It is therefore necessary to make the impregnation double-sided, ie to expose both sides of the mineral fiber web to particulate streams. I. Even if binder is added to the pre-cured primary webs, it may be appropriate to add a portion, preferably a smaller portion, of the binder already in connection with the fiberization and collection.

This gives the mineral fiber web a certain basic impregnation, which means, among other things, that the requirement for low basis weight in the later impregnation of none of the primary web or webs can be mitigated. There is nothing to prevent the use of different binders in the two steps in such a two-step impregnation. In fact, there should be a great advantage here, especially if a non-stick adhesive is chosen in the first step.

Most mineral fiber products must be equipped with something that eliminates or at least reduces dust emissions. Dust from mineral fiber 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 achieved mechanically, but it is also possible to use dispersants of a chemical nature. In some cases it is desired to avoid the bonding of binder and oil, and it is then appropriate to add oil in connection with fiberization and collection and to add the binder to the already formed web. g D In addition to fibers and binders, mineral wool usually contains 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 at the same time introducing binder particles from the surface layer is to expose the mineral fiber web or webs to the combination of a static, constant force directed at an angle to the web or webs, e.g. the gravitational force or pressure of an air stream, and oscillating energy, preferably acoustic energy of such frequency, and strength that particles on or in the orbits are caused to travel in the direction of the consonant force, removing not only undesired particles in the orbits but also desired particles from it the upper surface layer is forced to penetrate into the interior of the mineral fiber webs. In the mineral fiber 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 mechanical properties and insulating ability, respectively.

However, you may also want to give the mineral wool new properties. A supply of activated carbon in finely divided form in this way could give the mineral wool an absorption capacity for gases, which it would not otherwise. Such an absorption capacity would be valuable in certain contexts when the mineral wool is used as a filter. In Man, however, it has been very difficult to get such complementary particles to penetrate into the mineral wool. The fibrous structure of the mineral wool with very small mutual fiber distances gives the same good filtering properties, something which in itself can be Leftish-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, as 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 with the help of 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 pivoting energy; preferably acoustic energy. 452 040 The phenomenon which arises in this connection is very difficult to study in detail. It is believed that the acoustic energy causes such relative movements of the powder and / or the mineral fibers that the powder can move with the aid of the constant force in relation to the fibers to an extent which far exceeds the previously observed.

This mobility of particles in relation to the fibrous structure Q can now be utilized so that particles in the fibrous structure are thereby caused to migrate out of it. It turns out that the invention has 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 fiber web. Therefore, with a method according to this method, the mineral fiber 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.

Thus, the method can also be used to cause a powder, scattered over the mineral fiber web, to migrate into the mineral fiber 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 fiber 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 otherwise simplified. The discharged particles will then move away from the mineral fiber web as well as it will be easy to initially apply the powder to the surface of the mineral fiber web which is to be caused to penetrate into the mineral fiber web by the process.

As will be readily appreciated, the method can be applied only in one direction, - namely in the direction of the constant force. Often, however, one wants to remove particles from both surface layers of the mineral fiber 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 fiber web than would otherwise be possible.

It is thus expedient to allow the process described above to take place on both sides, whether it is now a matter of shaking or of shaking out particles. _ _ W The frequency and intensity that the oscillating energy must have in order to give the greatest effect is largely dependent on the density, orientation and diameter of the fibrous material and the shape, size and density of the powder and the loose g particles, respectively. 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 one simultaneously works with frequencies within two distinctly separated frequency ranges. As a rule, infrasound or sounds of very low frequencies prove to be suitable. The treatment that involves exposing the primary path (s) to a constant force and an acoustic energy should be initiated before introducing a liquid binaemeaei. _ i ¿_ The formation of the intermediate path can be accessed in different ways.

The simplest and generally expedient is to have the primary track or tracks discharged from a first, relatively fast conveyor system consisting of one or more conveyor belts or the like towards a more slow-moving conveyor system. The speed of the second transport system should in that case be considerably lower, preferably not more than half of the first transport system. . The thickening of the mineral fiber web that occurs during this reduction in speed is usually expressed in a fold. There is reason to control this folding so that it has a suitable course.

It can then suitably be controlled by, after the primary path or paths have been discharged from the first transport system, exposing them to impulses alternately from one side and from the other side. The impulses can be of a mechanical nature, but due to the speeds that are usually relevant, pneumatic impulses are generally more suitable. These impulses can consist of air shocks from alternating one and the other direction. However, it is also possible with the aid of the coanda effect in a fluidistor-like arrangement to cause the mineral fiber webs to deviate alternately in one direction or in the other.

When working with several primary courses, you have several options.

These can be combined after a possible impregnation within the first transport system, ie while maintaining the speed at which they were collected. The aggregation then takes place before delivery to the second transport system at its lower speed. The folding of the primary paths then takes place simultaneously. 4s2, o4oii, s no "However, a smoother intermediate path is obtained if the different primary paths are delivered separately and also folded separately on the receiving conveyor in a second conveyor system." 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.

Conveniently, 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. Thereby 7 lateral displacements and pulls are developed in the laid layers. g The properties of the mineral fiber products sought by the process are counteracted by the presence of melt splashes and unfibered particles. The risk of such is very special. large amounts of contamination if the collection takes place near 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 fiber webs is achieved while, of course, losses of melt are avoided.

The invention will now be described in more detail in connection with the accompanying drawings. It is to be understood, however, that the following description and the embodiments shown in the drawings are merely illustrative examples, and that many different modifications may be made within the scope of the appended claims.

In the drawings, Figure 1 shows a plant for the production of mineral fiber products by means of a method according to the invention.

Figure 2 shows an alternative device for producing mineral fiber products from a primary wool web. Figure 3 schematically shows an apparatus for producing products from four primary mineral fiber webs. Figure 4 similarly shows a device for producing products from three primary wool webs. Figure 5 shows a vertical section through a device for closed production of mineral fiber products according to the invention, and Figure 6 shows an application for double-sided impregnation of a mineral fiber web prepared according to the invention. . .

In The plant shown in figure 1 contains a shaft furnace 1, from 452 0-40 '.-. which a continuous melt flow 2 via a melt gutter 3 flows down on - a fibrillation assembly 4, which consists of a number of rapidly rotating cylindrical wheels; to whose mantle surfaces the melt is carried. Due to the action of the centrifugal force, melt particles are thrown out of the rotating wheels, thereby forming fibers. the plane of the wheels by means of a gas stream 5. 'The gas stream 5, which essentially The formed fibers are removed from the enclosing the fiber assembly comes via a line from a fan system not shown in the figure. The formed fibers 6 are carried towards a collecting device consisting of two perforated catching drums 7 and 8 placed one above the other. In the drums 7, 8 there are suction boxes 9, 10, which are evacuated through the ends of the drums 7, 8 by suction fans not shown in the figure. The gas stream 5 with fibers coming from the fiberizing unit hits the drums 7, 8. The gas 5 enters the suction boxes 9, 10 and further through the suction fans' supply out of the plant. The perforated drums 7, 8 are then left with fibrous layers 11, 12, which on rotation of the drums leave a single mineral fiber web 13. The upper drum_ rotates counterclockwise and the lower drum l0 clockwise. In order to facilitate the detachment of the fibrous web from the drums, there are two blowing ramps 14, 15 inside the drums, which cooperate with transport rollers 16. from which a stream of binder particles is directed towards the fibrous web 13. The path is then led down between two impulse means 19 and 20, which act alternately and give the path a waveform. The corrugated web Z1 is now laid down on a conveyor belt 22.

Because the conveyor belt 22 moves significantly slower than the web 13, the now formed web 23, which is called the intermediate web, has a substantially higher basis weight than the web 13.

Via a system of conveyor belts 24, 25, which cooperate with guide rollers 26, 27, the intermediate web 23 is guided to a folding device 28. The folding device 28 basically consists of two conveyor belts 29 and 30, which cooperate with a receiving belt 31.

The receiving belt 31 runs over rollers 32. The receiving belt 31 goes slower than the belts 29, 30 at the same time as these with their lower part make; 452 ~ o4o in _12 a reciprocating movement, and thus a final layer 33 will be deposited on the receiving belt 31, having an even higher basis weight than the intermediate web 23.

By carefully setting these mutual speeds and the movement pattern of the folding device 28, a final mineral fiber layer can be deposited on the belt 31 with a width and basis weight which within wide limits are within predetermined values. .

Figure 2 shows how the fiber-containing gas stream 5,46 is directed towards the drums 7 and 8 and then led in between the impregnation devices 17. The impregnated mineral fiber web continues to grow gracefully. speed between the impulse means 19, 20, which give the web a waveform.] The advancing mineral fiber web is directed towards and rests on the conveyor belt 34, which runs over rollers 35.- Under the conveyor belt 34, which is air-permeable, there is a suction box 36. This is evacuated through a conduit 37 of a fan not shown in the figure. Suglädan 36 has the task. to suck away the air present between the bays or waves in the mineral fiber web 23 when it settles on the conveyor belt 34.

The conveyor belt 34 moves at a speed which is substantially lower than the speed of the wool web, and the new, intermediate wool web formed on the conveyor belt 34 therefore has a higher basis weight than the wool web formed primarily on the drums 7, 8. Between the rollers 42 and 43, the intermediate wool web 44 is then compressed so that it has a reasonably smooth upper surface and is then fed into the folding device 28 between the conveyor belts 29 and 30. It is then laid out on the Vdet receiving conveyor belt 31 by the folding device 28, which perpendicular to the plane of the drawing. Figure 3 shows how a fiber-containing gas stream 45 is directed towards an arrangement of four perforated drums 46, 47, 48 and 49, which are evacuated by an evacuation device not shown in the figure. Layers are formed on the drums 46-49, which are removed by means of the conveyor belts 50, so that four primary fiber layers 51, 52, 53 and 54 are formed. These are impregnated separately by impregnating devices 55 and then laid down on a conveyor 56, so that a total, four-fold layer 57 is formed. This layer is then laid down on a conveyor belt 58, which runs slower than the conveyor belt 56. The laying on the conveyor belt 58 is controlled by the impulses 59 and 60, which work with compressed air.

Figure 4 shows an arrangement where a fiber-containing gas stream of beer in sz oao. [n. Y "ifatt * .gi, l is directed towards three perforated drums 62, 63 and 64, which as previously described each deliver their primary mineral fiber web 65, 66 and 67, which by means of conveyor belts 68, 69 and 76 are respectively carried forward and past By means of the encoders 72 and 73, one set for each path, the three paths 65, 66 and 67 are each laid down separately on a conveyor belt 74. This conveyor belt runs slower than the conveyor belts 68, 69 and 70, for which they the primary webs are folded, one on top of the other, so that a new intermediate web is formed by the thus-folded webs 75, 76 and 77. This intermediate web 75-77 is then passed to a folding device, in which a final web of predetermined basis weight Figure 5 shows how a primary web 78 is led into a chamber 79 - between two sealing rollers 80. In the chamber, the primary web 78 is employed by adhesive particles from impregnating devices 81, which can be constituted by compressed air nozzles. binder and any compressed air are passed by means of the lines 82. g From the chamber 79 the primary web falls into the chamber 83 together with an air stream 84, which also contains the binder particles which have not been attached to the primary web. At the entrance to the chamber 83, the path 78 is subjected to pulses from the jet nozzles 85 and 86, which are fed from the chambers 87 and 88. The latter is kept under overpressure, and connection to the nozzles 85 and 86 is provided via a valve not shown in the drawing. At the bottom of the chamber 83 is a perforated conveyor belt 89, which runs over a turning roller 90.

Below the conveyor belt 89 there is a suction box 91, which is evacuated through a line 92 by means of a fan device not shown in the figure. By the action of the jet nozzles 85 and 86, which operate alternately, the web will form bends 93 and 94 and then be deposited on the conveyor belt 89. The air, partly binder-particle-laden air coming from the chamber 79, will be forced to pass it on the belt 89 due to the structure of the device. closed track. The binder particles are then filtered off. The air passing out through the conduit 92 is taken in mainly next to the guide and sealing rollers 80. From the chamber 83 the now formed intermediate web is discharged between the rollers '95 and 96 and then passed on to a folding device in the manner previously described.

Figure 6 shows how the fibers in a fiber-containing gas stream 452 '14 are deposited on the perforated drums 7, '8, so that after the assembly a primary mineral fiber web 13 is formed. This mineral fiber tap is passed over a conveyor belt 97 under a device 98, which supplies binder for the mineral fiber web. The mineral fiber web 13 is then lowered to a new conveyor 99, where it is now driven with the previous underside facing up. From the impregnating device 100 the new top binder is supplied, and with the aid of a conveyor 101 the mineral fiber web is then moved again in the original joint and direction. The double-sided impregnated mineral fiber web 13 is then handed over to a new conveyor 102, which runs at a much lower speed than the conveyor 101. Thereby a new, intermediate mineral fiber web 103 is formed, which is folded in the manner previously described and subjected to other continued treatment.

Claims (27)

1. as? 040 '15 P a t e n t'k r a v 1. ' Process for the manufacture of mineral fiber products, especially those where the fibers are fixed to each other with a binder, so that a more or less dimensionally stable product is formed, whereby a mineral material, for example some stone or slag, is melted and in molten form is allowed to flow continuously. a fibrillation assembly (4), consisting of rapidly rotating cylindrical wheels, to which jackets the melt is passed, and from which it is ejected, forming fibers (6), which in turn are removed from the fibrillation assembly by a gas stream (5). and against a collecting device consisting of one or more movable, gas-permeable surfaces (7, 8), through which the gas penetrates while the fibers are delivered on the collecting surface (7, 8) in the form of one or more continuously advancing primary mineral fiber webs (11, 12). ), characterized in that the primary web (s) (11, 12) is removed at such a speed that the basis weight becomes low, that the speed of the primary web (s) in a later step g is reduced by supplying from a first conveyor system a second conveyor system which moves at a lower speed than the first conveyor system, preferably not more than half as fast, so that a new, intermediate web (23) is formed, the basis weight of which is greater than, preferably more than twice as large as the basis weight of the primary web (11, 12), or the total basis weight of the primary webs (13), and in that during a folding procedure (29-33) a final web is built up by the intermediate web (23), after which it is heat-treated, cooled and divided into desired pieces in a manner known per se. _ 2. A method according to claim 1, characterized in that the primary web or webs (51-54; 65-67) are impregnated (55; 71) before aggregation and deceleration. a w 13. Method according to claim 1 or 2, characterized in that the collecting distance between the fiberizing assembly and the collecting device is less than 800 mm and preferably less than 400 mm. 452if04ll to _16 .. 4 ,. Method according to one of Claims 1 to 3, characterized in that the basis weight of the primary web (11, 12) or the basis weights of the primary webs are below 200 and preferably below 100 g / m 2. _ 5. A method according to any one of the preceding claims, characterized in that the web or webs are passed past the mineral fiber material directed, in the direction of the webs widespread streams (e.g. 17) of binder particles, preferably drops of a liquid binder. Method according to claim 5, characterized in that the web or webs are moved freely during the impregnation step. A method according to claim 5 or 6, characterized in that the web or webs are impregnated on both sides. A method according to any one of the preceding claims, characterized in that liquid binder in drop form is applied in connection with fiberization and collection. _ ' A method according to any one of claims 4-8, characterized in that other additives, preferably dust binding oil, are added at the same time as the binder, preferably distributed therein, 10. A method according to any one of claims 1-8, characterized in that dust binding oil is supplied in connection with fiberization and collection. ' ll. Method according to one of the preceding claims, characterized in that each of the primary paths is exposed partly to a constant force, directed at an angle to the path or paths, eg the gravitational force, partly also at the same time thereby acoustic energy with such frequency and strength, that particles on or in the path or paths are forced to travel in the direction of the constant force. 12. A method according to claim 11, characterized in that a particulate material, for example a finely divided dry binder, is added and introduced. 13. A method according to claims 11 and 12, characterized in that the constant force is at least partially exerted by an air flow which is forced through the mineral fiber web. . l 1 14. A method according to claims 11-13, characterized in that the treatment takes place on both sides. 15. A method according to claims 11-14, characterized in that the treatment takes place before an impregnation of the primary web or the primary webs. 7 'Û, 452 o4o, '17 1 A method according to claim 1 ,. It is possible that the primary path or paths in connection with the transition from the first transport system to the second transport system are given impulses (eg through 19, 20), preferably pneumatic impulses, to assume a waveform, so that the closure of the other transport system takes place during folding. _ '' _ _ Method according to claim 16 in the presence of several prinear paths, characterized in that these primary paths (65-67) are supplied to the second transport system (74) one by one. in' A method according to claims 16 in the presence of several primary tracks, characterized in that these primary tracks (50-54) are first combined (57) before they are delivered from the first transport system (56) to the second (58). 19. A method according to any one of the preceding claims, characterized in that the folding process is designed so that substantially all parts of the intermediate web are discharged directly above the places where they are to lie in the final web and on the same height above the same. Method according to one of the preceding claims, characterized in that the melt jet (2) is protected and advanced so that melt splashes which can hit the collecting surface or the collecting surfaces are avoided; 's Device for carrying out the method according to any one of the preceding claims, consisting of one or more fibrillation assemblies (4) arranged to be supplied with a mineral melt (3) to form a stream of 2 mineral fibers (6), which after collection and processing form a final mineral fiber mat of desired thickness, characterized in that the device comprises a means (22) for forming an intermediate mineral fiber web (23) of the primary mineral fiber web (s), the intermediate web (23) having a basis weight which is greater than, preferably double as large as, the basis weight of the primary web or the total basis weight of all primary webs and a folding device which produces a final web of the intermediate web. , Device according to claim 21, characterized in that it consists of two or more catching drums (7, 8), which are arranged at a distance of less than 800 and preferably less than 400 mm distance from the fiberizing assembly (4), and which is counter-rotating, 452 040 Is I and on which the newly formed fibers (6) carried by a gas stream (5) are captured while the gas stream is diverted through the drums, the drums (7, 8) emitting a primary mineral fiber web (13), which after impregnation (17) is formed into the intermediate mineral fiber web (23L which in turn is formed into a final mineral fiber web) (Figures 1, 2, 6). Device according to claim 21, characterized in that it contains two or more parallel-acting catching drums (46-49; 62-64), which catch and each form a primary mineral fiber web (51-54; 65-67). , and in that the device comprises either means for forming from each primary web an intermediate mineral fiber web, which after aggregation form the final mineral fiber web, or means for fusing all primary webs and from these creating an intermediate web, which after folding forms the final mineral fiber web. (Figures 4 and 3, respectively) Device according to claim 22 or 23, characterized in that the means for forming the intermediate mineral fiber web consist of a folding means (e.g. 19, 20) for forming the primary web or webs by mechanical folding impulses or by air shocks or coanda effects. with reciprocating folds in the direction of travel of the primary web. A Device according to any one of claims 21-24, characterized in that it comprises means for subjecting the primary mineral fiber web or webs to a constant force, for example the gravitational force or the force of a gas or air stream, directed at an angle to the path or 2 paths and in combination therewith simultaneous acoustic energy of such frequency and strength that particles on and in the path are forced to travel in the direction of the constant force. Device according to any one of claims 21-25, characterized in that the means for applying binder consist of disc-like rotary spreaders, which emit a thin and wide jet of binder substantially over the entire width of the mineral fiber web. Device according to any one of claims 21-26, wherein the fibrillation sees through ejection from the mantle surface of rapidly rotating wheels, characterized in that the melt jet is protected from particles ejected from the wheels. IN