SI8210401A8 - Centrifugal device for forming mineral fibers and coating the samewith glue - Google Patents

Description

A technical problem

Based on the preparation of a centrifugal type for forming and drawing mineral fibers in which molten fiber production material flows to the outer circumference of the wheels, where fibers are formed by centrifugal force, the invention is based on the problem of how to further develop this device in order to improve it. the mechanical and insulating properties of the fibers and these fibers are evenly coated with a diffused bonding fluid and that the preparation will allow continuous production.

The state of the art

Free spin is known, in which a jet of molten mineral material is fed to the circumference of a rotating wheel and then to the circumference of the second or third rotating wheel. Furthermore, arrangements are known for supplying molten material to the axis of a spinning wheel having nozzles for discarding fibrous jets of molten material near the circumference of the spinning wheel.

A device is also known in which the fiber material is laughed at the head of the disc or a drum whose periphery is perforated and equipped with nozzles from which the material escapes under the influence of centrifugal force.

Centrifuging with a reel does not lead to fine fibers. In addition, the use of certain materials used in this type of product is prohibited.

Techniques whereby fiber production is performed by feeding material externally to the circumferential surface of the wheels are also not satisfactory.

Given the large number of factories in fiber formation, these techniques are difficult or difficult. little suitable for systematic analysis.

Various suggestions have been made to improve these techniques, but fiber production could not be considered separately from the technology of gluing fibers into the carpet.

In one known embodiment, the scattering is carried out in the path of a gas jet that carries the fibers to the collecting surface at a distance from the fibers to form the fibers. However, this method does not guarantee a homogeneous coating of fibers.

In order to improve the coating of the fiber with the bonding fluid, it has already been suggested that the bonding fluid be sprayed onto the fiber path on the other side of the fiber forming wheels at the same speed and in the same direction as the gas-carrying fiber. However, even these measures did not improve the results in a satisfactory way.

In order to prevent the problems mentioned above, it has already been suggested that the bonding fluid should be sprayed near the fiber forming wheels, preferably in a gas jet designed to drain the fibers and to separate the fibers from the improperly processed particles. In this case, it diffuses into the gases before they get in contact with the fibers.

One of the disadvantages is the installation of spray elements near the surface of the wheel. In this position, the spray elements are exposed to thermal radiation from surfaces which, due to contact with the molten material, are heated to a high temperature. The spray elements are exposed to the spray of the molten material. In this way, the lining that clogs them quickly appears on the spray elements. To reduce this disadvantage, they can otherwise use nozzles whose outlet mouths are relatively large, which for a given flow means a reduction in the number of nozzles. Due to the smaller number of nozzles, the nozzles are more spaced apart, resulting in a non-homogeneous assembly of fibers, which degrades the quality of the finished product.

In the case of multi-castors for fiber production, it is desirable from the point of view of the material coming from one wheel to the other to prevent blowing and / or scattering between the wheels, in particular in order not to cool the material which has not yet been converted into fibers. . In general, they tried to form fibers outside these zones between the wheels. However, a certain amount of fibers, which have either been formed or taken away, enter these zones so that the dispersed binder does not come directly into contact with these fibers, which of course increases the inhomogeneity.

A description of the solution to a technical problem with examples of execution and a list of images

The problem is solved according to the invention in the pursuit of the goal of creating means by which fibers can be better formed and processed, to increase the percentage of the material obtained in the form of fibers in relation to all the material used, in order to improve the quality of the product obtained, in particular its mechanical and insulating properties, and to facilitate continuous operation of the device by reducing the frequency and duration of shutdowns.

It is a further object of the invention to improve the adhesive coating of fibers, whether or not the fibers appear in the form of a web. According to the invention, the fiber production material is guided in a state to be towed to the circumferential surface of the centrifuge wheel. At least a portion of this fiber-shaped material departs in the radial direction, after which these fibers are taken away by a gas jet, which is transverse to the wheel in the direction of departure of the fibers. The fiber-bearing gas jet deviates from its original path and comes into contact with the liquid binder in a diffused state for treating the fibers.

It is proposed to introduce a binder from the inside of the fiber layer transversely to the carrier gas stream. The force that must be exerted on the liquid binder originates from the rotation of the mechanical element into which the adhesive enters, which subsequently flows under the influence of centrifugal force and penetrates the gas stream.

The fiber layer and the gas flow that it carries are oriented in such a way that they essentially follow the direction of the rotational axis of the wheel.

Centrifugation of the liquid adhesive proceeds from an element which is compatible with the fiber fabrication wheel. Liquid adhesive droplets fly off essentially perpendicular to the rotary axis and to the gas stream carrying the fibers. The adhesive is sprayed close to the fiber forming wheel, as long as the droplets meet the gas-carrying gas stream at a point where the gas flow has not yet been disturbed by the ambient air mixing.

In preferred embodiments, the distance separating the downstream edge of the centrifuge wheel from the plane in which the adhesive is sprayed is of a maximum size of 150 mm and preferably less than 60 mm at a gas flow distance from the surface of a spinning wheel of the order of 10 to 200 mm, preferably 25 to 100 mm.

The radial exit velocity of the adhesive is between 50 and 120 m / s, preferably between 70 and 100 m / s.

Liquid adhesive is normally applied under minimum pressure.

In order to facilitate the delivery and penetration of droplets into the gas stream, it is desirable that the droplets be relatively large, since the final dispersion of the droplets is effected by the action of a gas stream.

Under the preferential conditions of rotational velocity and blowing velocity, the droplet droplets have average dimensions that are 10 times larger than the aerosol droplet dimensions which they consider to allow good distribution. So we have e.g. in conventional water-based adhesive intended to be sprayed on mineral fibers, 90% of the droplets with an average size of 30 χ IO ^-6 m. However, if the adhesive is sprayed by centrifugation, the droplet size will be between 50 x IO ⁶ and 500 χ IO ^-6 m, with an average of 250 χ 10 ^-6 m.

The gas stream is designed as a wrapper around the spin wheels and reaches a speed of between 50 and 180 m / s, preferably between 100 and 150 m / s, at a circumferential speed of the spin wheels, depending on the substance used (slag, basalt, diabase, glass) from 60 to 150 m / s. Under these conditions, the gas velocity to circumferential velocity displacements are between 1.8 and 0.8, and in particular between 1.5 and 1.

Increasing the speed of gas flow helps to produce finer fibers.

The amount of carrier gas must be sufficient for a uniform velocity along the wheel surface so that the gas diverts and takes with it the fibers as well as the adhesive. It is advisable that in the case of water vapor, its amount is 0.5 to 2 kg per kilogram in the fibers of the processed material.

The distance between the outlet nozzles and the upstream edge of the surface of the fiber wheel should be as small as the construction allows. By placing these mouths closer to the wheel surface, it is ensured that the flow velocity at the wheel level will be barely different from that at the point of discharge.

The distance between the outlet mouth and the level relative to the flow of the upstream edge of the wheel surface is preferably less than 50 mm.

The outlet nozzles can be positioned at the level of the wheel surface or even slightly beyond, without disturbing the fiber path.

If we use small-sized jets that come from a mouth whose width does not exceed 6 mm, preferably between 0.5 and 5 mm, and under the conditions previously stated for the distance between the mouth and the surface of the wheel, which is required to give a suitable velocity to a gas stream, typically ranging from 1 to 10 χΙΟ ⁵ Pa.

The fiber fabricator according to the invention comprises at least one centrifugal wheel, on which the outer circumference laughs the material to be stretched. A feature of the invention is that the device comprises an adhesive fluid spraying element by centrifugal force. This element is positioned relative to the spinner wheel so that the adhesive protrudes at a distance from the rotary axis of the wheel that is almost identical to the radius of that wheel.

The adhesive spray element is connected to a spinning wheel, which is also rotary driven. Preferably, this element and the fiber forming wheel are coaxial. This element preferably has the shape of a reel consisting of two interconnected supports that define the adhesive chamber with one another. This chamber is connected, on the one hand, to the inlet duct and, on the other, to the mouth, which is located at or near the circumference of the reel. The mouth may be designed as a circular slot. The nozzles are arranged in a circle sufficiently close to each other, also in several concentric rows, preferably on one side of the spray element on a plane substantially perpendicular to the rotary axis and at a certain distance from the circumference.

To guide the adhesive radially to the circumference of the disc, grooves or radial fins are provided on the surface of the adhesive.

In order to prevent heat transfer between the fiber forming wheel and the integral spraying element, an attachment is provided near the hub, i.e. in an area that is slightly exposed to heat, with a distance of several millimeters between the wheel carrier and the spray element. The work surface of the wheel can protrude through the supports and even through the part of the liquid glue spray element.

A circular flange mounted on the wheel carrier may be used to secure the adhesive release element. A special element that is attached to the bracket may also be used.

In all cases, the radial dimensions of the spraying element shall be such that the adhesive is sprayed at a distance of at least 70% of the radius of the fiber forming wheel.

For the supply of liquid adhesive to the sprinkler element, there are axial grooves arranged in the wheel shaft.

Preparations for the manufacture of fibers from materials requiring high temperatures generally provide means to prevent deformation and rapid wear of the parts subjected to the highest stresses. To this end, cooling water is provided through the ducts located in the wheel shaft, which protects the liquid adhesive from unwanted increase in temperature.

In a variant embodiment, the spray element is a rotating surface to which the adhesive is applied. To counteract this, the disc has faces extending perpendicular to the rotary axis, which is achieved by grooves or radial ribs that prevent the fluid composition from sliding. In a further modification, the sprinkler element is a concave plate i.pd.

The fiber forming device generally has a first wheel, which is tasked with accelerating and dividing the material into the adjacent wheel. This first wheel has virtually no fiber production, so there is no need to be equipped with a blower element.

The flow of gas must take place in a continuous layer, so the mouths should be positioned so that the adjacent jets are in contact with each other.

We usually use one type of mouthpiece; However, if there is a need to increase the gas flow or to provide a constant speed along the surface of the fiber forming wheel, it is possible to install several types of mouthpieces, among which may be those having different characteristics: the dimensions of the mouth, their inclination in relation on the wheel axis or their relative position relative to the wheel. Number or the dimensions of the mouths are selected as a function of the zone to which these mouths belong. In areas where a large amount of fiber is separated from the bicycle, it is desirable to have several larger mouths or to have a larger number of mouths. The mouth is powered by a ring-shaped chamber.

In the following description we will describe in detail the preparation according to the invention based on the accompanying embodiments and the accompanying drawings, in which FIG. 1 shows a device for forming, separating and spraying fibers according to the invention in perspective projection; 2 is a side elevation view of a fiber fabrication wheel according to the invention, FIG. 3 is a detail view of the assembly of FIG. 2, FIG. 4 shows a further detail of the assembly of FIG. 2, FIG. 5 is a schematic view of the main elements of a device according to the invention with measurement data determining the relative position of these elements; FIG. 6 is a detail of a cooling water inlet, FIG. 7 is a detail of a supply line for a liquid adhesive composition, and FIG. 8 is a radial cross-sectional view of a portion of another embodiment of a diffuser element of a liquid fiber adhesive composition.

The preparation of FIG. 1 comprises three spin wheels 1, 2,

3, of which the hollow wheels 2, 3 are assembled to form fibers, and wheel 1 is a distributor wheel. The fiber forming material flows from channel 4 to the distributor wheel 1. Here, it accelerates and passes to the wheel 2, which rotates in the opposite direction from the wheel 1. The material, which is not sufficiently fastened, flies from the wheel 2 to the wheel 3, the rest of the material. , which is sufficiently cohesive, accelerates until it is detached in the form of jets due to centrifugal force.

These jets run into the gas stream surrounding wheel 2 and take it with them against a perforated conveyor belt not shown in the plan. Gas flow is generated in the mouth, which is located on the blower 5. This wreath produces gas flow only in the areas where the fibers peel off. tear from wheels 2, 3 to form fibers.

Preparations with four or only two wheels are also possible.

In FIG. 1 is a spray roll 10 for liquid adhesive surrounded by a flange 32. The adhesive protrudes through the annular slot 22 at the head of the spray roll 10. In FIG. In Fig. 2 shows the elements of the device according to the invention that are directly involved in the formation of fibers, namely a spinning wheel 3 consisting of a ring 7, which is mounted between the beams 8, 9 and mounted on a shaft 6, a spray disc 10 consisting of two beams 11, 12, and a stationary blower locus 13 integral with the frame not shown.

A detail of the shaft assembly 6 is given in FIG. 3 and 4. The bracket 8 is pressed against the annular support 17 of the shaft 6. Each of the brackets 8j 9 has a projection 14, 15 at its circumference, which rests in the corresponding groove of the ring 7. The end of the hub 16 of the bracket 11 of the 10-strong ring 10 is inserted into the recess of the support 9 The hub 16 is screwed to the projecting threaded end 18 of the shaft 6, thereby interconnecting the support 8, 9 and the ring 7.

An embodiment of the spray roll 10 and the channels for supplying cooling water and liquid glue are shown in FIG. 7, where, for the sake of clarity, no vi1.1 is shown. t strong 19. The disc bracket 12 is secured to the bracket 11 by means of unscrewed screws at the level of the shelf 20. The brackets 11, 12 thus form a liquid adhesive chamber 21. The chamber 21 is open to the outside through a separate annular channel 22. The adhesive flows from the chamber 21 towards the channel 22 through a series of grooves cut into the shelf 20.

In the axis of the shaft 6 are located concentric channels 23, 24. The inner channel 23 leads the adhesive to the chamber 21, and the outer channel 24 contains cooling water for the wheel 3. The channels 23, 24 are connected by means of a ring pin 25, which closes the channel 24 The plug 25 may be twisted or otherwise secured. The grooves 23, 24 are positionally held in the axis of the shaft 6 by means of a rolling bearing 26 mounted on the inside of the hub 16. The bearing 26 is longitudinally supported by a spring ring 27 and on the other side it rests on a gasket 28 that rests on the hub attachment 29 16.

The cooling water circulation (Fig. 6) is driven by a channel 24 and its intermediate openings 34 inside the shaft 6 and the throat 30, which is made in the wall of the shaft 6.

The throat 30 directs the water towards the openings 31 which are located at the base of the throat 30 so that water flows between the supports 8,9 of the wheel 3- As shown in FIG. 3, the openings 31 are angularly displaced relative to the screws 19.

When water comes in contact with ring 7, it evaporates and escapes through the non-exposed openings on the sides of the wheel 3 ·

A variant embodiment of the spray disc 10 is shown in FIG. 8.

rii

Liquid adhesive flows to the concave conical disc 33, the concave part of which is facing the wheel 3, and then drains away from the inside of the concave conical disc 33. The conicity of the disc 33 holds the adhesive in its travel towards the circumference of the disc 33 in a disjointed state.

FIG. 4 shows an embodiment of a safety flange 32 for a spray disc 10. The flange 32 is fixed to the support 9 and partially encloses the disc 10. The edge of the disc 10, of course, from which drops of liquid adhesive fly off, is of course not obscured.

Ring 7 is provided with non-exposed longitudinal grooves to facilitate material gripping.

Claims (5)

PATENT APPLICATIONS A centrifugal device for forming mineral fibers and coating them with an adhesive, characterized in that an integral hollow wheel (2, 3) is arranged on the hollow shaft (6) of the associated hollow wheel (5). wheels (2, 3) connected by screws (19) inserted through the wheel (2, 3) and screwed into the annular backrest (17) of the shaft (6), the assembled hollow spray disc (10). Device according to claim 1, characterized in that the assembled hollow wheel (2, 3) comprises disc supports (8, 9) which, with their respective circumferential outgrowth (14, 15), hold the working ring (7) in a locking manner, and that the spray disc (10) consists of disc brackets (11, 12) surrounding the chamber (21), the bracket (8) being mounted on a shaft (6) to the annular support (17) and the bracket (11) being screwed to the threaded end (18) of the shaft (6) and with its hub (16) rests on the bracket (9). Device according to claim 1 or 2, characterized in that the support (11) is supported by a spring ring (27) against the threaded end (18) of the shaft (6) via a rolling bearing (26), which is held against the carrier (12) by a spring ring (27). ) and sealed with a gasket (28) that rests on the hub (29) nozzle (16), pivotally connected to the tubular axial groove (24) through which it is inserted and through it via a ring pin (25) separating the inside of the groove (24). ) from the chamber (21), a tubular channel (23) is connected, wherein openings (31) are arranged between the supports (8, 9) and openings (34) are arranged opposite them in the wall of the shaft (6), meanwhile when the channel (23) is open towards the chamber (21). Device according to one of Claims 1 to 3, characterized in that the disk carrier (12) with the inner surface rests on the grooves provided with the shelf (20) of the carrier (11) to which it is attached, opposite to the supporting surface at the circumference of the carriers (11, 12) form a separate annular outlet duct (22). Device according to one of Claims 1 to 3 and in modification I, characterized in that a concave conical disc (33) having an external diameter equal to the carrier (9) is mounted with screws (19) on the hub (16). the outer diameter of the ring (7).