US3745060A - Heat insulating fibrous mass - Google Patents

July 10, 1973 R ET AL 3,745,060

HEAT INSULATING FIBROUS MASS Original Filed May 6, 1968 8 Sheets-Sheet '1 INVENTOR-S C4 4005 JUME'A/T/'fi 144 4/11! 504/4157 y 1973 C.JUMENTIER ETAL HEAT INSULATING FIBROUS MASS Original Filed May 6, 1968 8 Sheets-Sheet July 10, 1973 C JUMENT|ER ET AL 3,745,060

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Original Filed May a, 1968 July 10, 1973 C'JUMEN-HER ET AL 3,745,060

HEAT INSULATING FIBROUS MASS Original Filed May 6, 1968 8 Sheets-Sheet 4 July 10, 1973 c JUMENTER ET AL 3,745,060

HEAT INSULATING FIBROUS MASS Original Filed May 6, 1968 8 Sheets-Sheet f July 10, 1973 QJUMEN'HER ET AL 3,745,060

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July 10, 1973 QJUMENTER ET AL 3,745,060

HEAT INSULATING msnous mss Original Filed May 6, 1968 8 Sheets-Sheet 7 July 10, 1973 IER ET AL 3,745,060

HEAT INSULATING FIBROUS MASS Original Filed May 6, 1968 8 Sheets-Sheet a United sate; Patent 6 3,745,060 HEAT INSULATING FlBRUlUS MASS Claude Jumeutier, La Celia Saint Cloud, and Alain Bonnet, fllermont, France, assignors to Compagnie dc Saint-Gabain, Neuilly-sur-Seiue, France Original application May 6, 1968, Ser. No. 726,706, now Patent No. 3,616,030. Divided and this application Dec. 23, 1970, Ser. No. 101,060

Claims priority, application France, May 11 1967,

This is a division of application Ser. No. 726,706, filed May 6, 1968, Patent No. 3,616,030, Oct. 26, 1971.

The invention relates to the production of plates or sheets shaped from a mass of mineral fibers, particularly glass fibers, agglomerated by a binding agent, which present at the same time both a high insulating capacity as well as a high degree of indeformability. According to one characteristic of the invention, these plates or shaped sheets are constituted by a lattice-work or network of fibers which are joined to each other by a binder and by solid and indeformable particles in the form of unitary granules which are interlocked and encompassed separately in the meshes of the fiber network and distributed in a homogeneous fashion therein.

It is another characteristic of the invention that the particles which are employed are at the same time hard, whole and iudeformable, while being either solid or porous.

It has been determined that While the products of the invention present a very low tendency to deformation, particularly compression, they retain strongly the high heat-insulating capacity inherent in the porous structure of a mass of mineral fibers. This preservation of the high insulating quality is due to the fact that the hard particles or granules are in contact with the fibers of the meshes which encompass them only along points or lines of slight length, and thus there is practically no formation of thermal conducting paths or bridges between the particles and the fibers.

The high degree of indeformability of the products of the invention arises from the fact that each particle impedes the local deformation of the network in which it is enclosed, and that by reason of the homogeneous distribution of the particles in the entire mass, the deformation of the whole of the mass is prevented by the presence of all of these particles.

In a general way, it is possible to select the average granulometry of the particles which are used, as a function of the volumetric mass which is related to the mass of fibers. In all cases, the size of the particles or granules should be such that they are enclosed within the meshes of the network formed by the fibrous mass. If these meshes are very fine, small granules or particles of light granulometry are used; if the meshes are large, particles of larger dimensions may be used.

According to one embodiment of the invention, the fibers constituting the network may have a mean diameter between 3 microns and 16 microns; the apparent volume-mass characteristic or density of this fibrous mass may range between 25 kg. and 200 kg. per cubic meter, and preferably between 35 kg. and 100 kg. per cubic meter; the granulometry of the solid, whole, indeformable particles may be of the order of 0.10 mm. to 0.6 mm. and the proportion by volume of the mass of particles may be of the order of 2% to 20%, and preferably 3% to 15% of the total volume of the product.

According to another embodiment of the invention, the apparent volume-mass characteristic or density of the fibrous network may range between 35 kg. and 100 kg. per cubic meter, and the particles enclosed in the meshes of this network may be constituted by grains of sand of a granulometry of the order of 0.10 mm. to 0.40 mm.

Instead of sand, other solid particles may be used, for example, crushed glass, crushed rock, melted coal ashes, etc. The condition which these particles must always meet being that they are hard and indeformable.

Another improvement results from the use of hard and indeformable granules which include empty spaces. Advantageous characteristics are imparted to the structural units of the invention by the use of hard porous or foamed mineral particles, such as perlite or vermiculite. The products resulting from the use of such components are characterized by extremely light weight, high insulating capacity and a high degree of indeformability.

When use is made of fibrous masses having a slightly elevated specific density, the presence of these particles therein, particularly perlite, result in products which evi dence a strong resistance to deformation, particularly compression.

In the modes of execution of the invention with hard porous granules, the constituent fibers of the network may have a mean diameter ranging between 3 microns and 16 microns, the apparent volume-mass characteristic or density of this network may range between 8 kg. and kg. per cubic meter, preferably between 8 kg. and 50 kg. per cubic meter, with the granulometry of the granules being above 0.1 mm., and preferably between 0.5 mm. and 5 mm., and the proportion in volume of the mass of particles being of the order of 3% to 80%, and preferably between 10% and 50% of the total volume of the product.

The quantity of particles which is used per unit of volume of the final product depends on the density of the product and the mechanical properties which are sought to be attained. To obtain identical mechanical properties, for example, identical resistance to crushing under load, it is desirable that the proportion of particles be greater as the quantity of constituent fibers per unit of volume is lower. Otherwise, for a like quantity of fibers per unit of volume, the greater proportion of granules results in a higher degree of mechanical resistance.

It is the object of the invention to provide a method of producing structural units in the form of plates or shaped sheets of high insulating capacity and indeformability, as described above. This method consists in introducing the hard and indeformable particles, either in solid or porous form, throughout the mass of fibers in homogeneous fashion, by flowing the particles and projecting them into the mass of fibers which is treated with a binding agent, by the action of a gaseous current, and by then reducing the volume of said mass in such a way that the particles are completely enclosed and interlocked between the fibers after the binder sets. The reduction of volume may be effected advantageously by exerting a suction efi'ect through the mass of fibers.

As a variation, the method may also be executed by introducing all or part of the binder together with the solid or porous granules or particles, into the mass of fibers. Thereby a better distribution of the binder within the network of fibers is obtained. It has been determined that the binder introduced with the particles moves from the surfaces of the particles towards the fibers and assures the joining of these fibers at their crossing points without the binder remaining in contact between particles and fibers, thereby avoiding all thermal bridges between them.

In accordance with the invention, provision is made to vary the quantity of granules or particles introduced into the mass of fibers, which may be varied in dependance upon the mechanical characteristics sought to be imparted to the product.

The invention contemplates many different devices for executing the procedures described above. These devices comprise a distributor, wherefrom the particles flow by gravity, and members, such as blowing nozzles, for producing gas jets, which act on the particles to project them into the mass of fibers and distribute them homogeneously in the latter.

According to one embodiment of the apparatus, the projection of particles takes place on one side of the mass of fibers.

According to another embodiment of the invention, the distributor and blower members are arranged around the mass of fibers issuing from the production apparatus, and there is provided, under the blower members, an oscillating nozzle or conduit into which passes the mass of fibers with the particles which have been incorporated in it. The oscillations of the nozzle or conduit make possible the regular distribution of fibers on the cloth or other receiving surface onto which the mass is projected for the formation of a mat or sheet.

It is the particular objective of the arrangements in accordance with the invention to secure an efiective homogeneous distribution of the particles in the mass of fibers. This may be attained by introducing the granules or particles into the gaseous currents in the form of a sheet of particles which flows in a homogeneous and uniform fashion. This may be accomplished by feeding the particles onto a distributing surface surrounding the mass of fibers, which particles flow in a homogeneos and uniform fashion from the distributing surface in the form of a sheet which is subjected to the action of the gaseous currents. One of the features of the invention is that the particles move freely on the distributing surface in forming a natural flow.

When the fibers are produced by a rotary centrifuge, of the type well known in the art, the attenuated fibers gravitate in the form of a torus-shaped mass having a rotary movement. In this case, the particles may be projected into the mass of fibers by imparting a rotary movement to the annular sheet of granules which has a component in a direction opposite to the direction of rotary movement of the mass of fibers.

Also, the apparatus in accordance with the invention comprises a distributing member in the form of a crown surrounding the mass of fibers with elements which supply the particles onto the crown in the form of threads or streams. The crown has an inclination or slope at least equal to the slope of collapse or the angle of repose of the granules so that the several streams form sheets, which, by virtue of the positioning of the points of supply of the particles, merge together at the rim of the distributor crown to form a continuous and homogeneous layer of uniform thickness, which is then projected onto the mass of fibers by the blowers.

In accordance with another feature of the invention, the elements which supply the particles onto the distributor crown are formed by conduits which communicate with an apparatus which feeds the particles through a plurality of orifices, beyond which, the thickness of the beds or layers of particles issuing from the several orifices, is maintained substantially the same.

In accordance with another feature of the invention, the apparatus supplying the particles may consist of parallel tubes fitted with screw conveyers which advance and circulate the particles and feed them in streams or layers of substantially constant and adjustable thickness beyond the orifices which supply the conduits. The latter are preferably in the form of sluices or channels. In order to permit the regulation of the passage of the particles which enter these conduits or sluices, members in the form of perforated masks may be applied around the supply tubes along the length thereof, which permit any desired adjustment of the orifices through which the particles pass.

In another embodiment of the invention, the apparatus for feeding the particles consists of a tube in the form of a torus, which is disposed adjacent to the inclined wall of the crown, and which contains openings through which the particles flow onto the inclined wall. A helical member is provided in the tube for conveying the particles therethrough.

Other objects and purposes of the invention will appear from the following description in conjunction with the accompanying drawings, which illustrate several non-limiting examples, and wherein FIG. 1 is a view of a mass of interlocked mineral fibers, on a greatly enlarged scale, with binding agents incorporated therein,

FIG. 2 is a view similar to FIG. 1, following the compression of the mass of fibers in a vertical direction;

FIG. 3 is a view similar to FIG. 1 with the inclusion of separate hard and indeformable particles in the network of the mineral fibers, in accordance with the invention;

FIG. 4 is a view similar to FIG. 3 following the deformation of the mass of fibers by a compressive force of the same intensity as that employed on the mass shown in FIG. 2;

FIG. 5 is a front elevation, with certain parts in section, of an apparatus for executing the invention;

FIG. 6 is a sectional view, with certain parts in elevation, of a second embodiment of an apparatus in accordance with the invention;

FIG. 7 is a partial view of FIG. 6, on an enlarged scale, at the outlet of the receptacle and blower for the hard particles;

FIG. 8 is a front elevation of another embodiment of the invention, illustrating the incorporation of the granules within the mass of fibers issuing from a different form of fiber-producing apparatus;

FIG. 9 is a perspective view of still another embodiment of the invention;

FIG. 10 is a vertical sectional view through the installation shown in FIG. 9 with certain parts in elevation;

FIG. =11 is a diagrammatic plan view of the distributor shown in FIGS. 9 and 10, and indicating schematically the disposition of the conduits or sluices for feeding the hard particles thereto;

FIG. 12 is a vertical sectional view of a portion of the distributor crown at the outlet end of the supply conduits, illustrating the flow of the particles onto the distributor surface;

FIG. 13 is a vertical sectional View along line 13-13 of FIG. 9;

FIG. 14 is a sectional view of one of the perforated masks which are mounted along the supply tubes shown in FIGS. 9 and 10;

FIG. 15 is a side view of the mask shown in FIG. 14;

FIG. 16 is a perspective view of another embodiment of the invention; and

FIG. 17 is a sectional view along line 17-1.7 of FIG. 16.

FIGS. 1 to 4 illustrate graphically the advantageous features of the instant invention.

FIG. 1 shows a part of a mass of mineral fibers 1 which, as is known, are joined together at cross-points by a binder. Four of these cross-points are marked A, B, C, D.

If this mass is subjected to a mechanical stress, such as, for example, compression (FIG. 2), it is seen that the thickness of the mesh or lattice-work of fibers decreases, and that the quadrilateral A, B, C, D is reduced to form quadrilateral A, B, C, D.

FIG. 3 shows the same fibrous structure as that shown in FIGS. 1 and 2, but one in which hard, whole and indeformable particles or granules 2 are introduced and interlocked between the meshes of the network of fibers. The preceding cross-points are marked A", B", C", D" and occupy substantially the same relative positions as the cross-points indicated in FIG. 1. If the mass is subjected to the same compressive stress as that imposed on the unit shown in FIG. 2, the resulting product is illustrated in FIG. 4. It is seen that the presence of each particle prevents deformation of the mesh in which it is enclosed, the points A, B'", C' D' remaining in the same positions as points A", B", C", D", and that the assembly itself undergoes a decrease in thickness of much less extent than that in the case illustrated in FIG. 2.

FIG. 5 illustrates one embodiment of an apparatus for obtaining a fibrous mass according to the invention as shown in FIGS. 3 and 4.

Any suitable polymerizable resins may be used as binding agents, examples of which are set forth below. Furthermore, variations may be made in the details of the apparatus, for example, in the character of the air-permeable conveyor for receiving the mass of fibers combined with a resin binder and hard particles distributed therethrough. As set forth above, the latter may be in the form of hard solid and indeformable granules, such as sand, or these granules may be hard and indeformable with voids therein such as foamed or porous granules of perlite or vermiculite. The invention also contemplates the use of hard and indeformable light particles which are interlocked in the meshes of the fibrous network, such as crushed, foamed or porous glass.

Below are given examples of products of glass fibers according to the invention as well as comparative data, between these products and the same products which do not include hard and separate unitary solid or foamed indeformable particles, from the point of view of heatinsulating capability and resistance to deformation.

(b) Mean diameter of fibers: 6 microns Nature of binder: Phenol formaldehyde resin (d) Nature of particles: Sand (e) Mean diameter of grains: 0.2 mm.

Load

required Coefficient to reduce of thermal thickness conductivof product Composition of ity, KcalJ by Product product mm, C. kg./1n.

With sand Resin: 2 kg./m. 30. 2 880 Sand: 60 kg./m.

NorE.Kg./m. is abbreviation for kg. per cubic meter; kgJm. is abbreviation for kg. per square meter.

It is to be noted that while the products have substantially the same insulating power, the load necessary to obtain the same reduction in thickness in the product in accordance with the invention is nearly double.

EXAMPLE II Identical with those of Example I:

(a) Composition of the glass (b) Mean diameter of the fibers (0) Nature of the binder ((1) Nature of the granules or particles (c) Mean diameter of the granules Load required Coetficient to reduce of thermal thickness conduetivof product Composition of ity, KcalJ by 25%, Product product m. C. kgJm.

Fibers: 64.5 k ./m. Without sand 5.5 g 28.0 1, 510

Fibers: 54.5 kgJm With sand ..{Resln: 5.5 kgJmfimn} 31.0 2, 300 Sand: kg./m.

(2.) Composition of the glass: Percent SiO 61.3 A1 0 5.5 F 0 0.6 CaO 7.3 MgO 3.1 Na O 13.9 K 0 1.9 B 0 2.9 BaO 3.2

(b) Mean diameter of the fibers: 12 microns (0) Nature of binder: Phenol formaldehyde resin (d) Nature of granules: Sand (e) Mean diameter of granules: 0.2 mm.

Load required to reduce thickness oi product by Composition of 2 Product product kgJm.

Fibers: 99 kg. m.

Without sand 11 j 9,000

ibers: 99 kgJmfi- With sand Resin: l1 kg.lm. 16,000

Sand: 90 kg./m.

Set forth below are two examples of products of glass fibers with perlite and vermiculite, according to the in vention, these examples showing, comparatively, the differences from the point of view of insulating value and resistance to deformation between these products and the same products which do not include these particles.

9 EXAMPLE IV-Continued (a) Composition of glass: Percent 0.2

(b) Mean diameter of fibers: 6 microns (c) Nature of binder: Phenol formaldehyde resin (d) Nature of grains: Perlite (e) Diameter of grains: 0.1 mm. to 2 mm.

Load

required Coefliclent to reduce of thermal thickness conductivof product Composition of ity, KcaLl by 25%,

Product product m.7\, C. kgJm I Without perlite 2 {52 3 Fibers: 36 kgjmfin With perlite Resin: 4 kg./m. 30.0 2, 200

Perlite: 18 kgJml- It is to be noted that while both products have substantially the same insulating capacity, the load required to attain the same reduction in thickness is nearly tripled for the product in accordance with the instant invention.

We claim:

1. A heat-insulating product composed of a mass of mineral fibers agglomerated with a binder and characterized by a high insulating value and high resistance to compression and mechanical deformation, comprising a mass of mineral fibers arranged in an intersecting network of fibers agglomerated together at their intersecting points with a hardened binder and having separate spaced mineral particles which are hard and indeformable and which are homogeneously interspersed and interlocked in the spaces between the intersecting fibers and in contact with a plurality of said intersecting fibers within said spaces, to impose a limited capability of deforming movement thereto while retaining some of the air voids therebetween.

2. A product as set forth in claim 1 wherein the mineral fibers are freshly formed and attenuated glass fibers having mean diameters ranging from 3 microns to 16 microns, the density of the mass of fibers ranges from about 25 kg. to 200 kg. per cubic meter, the granulornetry of the hard particles ranges from about 0.10 mm. to 0.60 mm. with the proportion of solid particles ranging from about 2% to 20% of the total volume of the product.

3. An article as set forth in claim 1 wherein the hard and indeformable particles are solid and full.

4. An article as set forth in claim 3 wherein the particles are grains of sand.

5. An article as set forth in claim 1 wherein the hard and indeformable particles have void spaces therein.

10. A product as set forth in claim 1 wherein the mineral fibers are freshly formed and attenuated glass fibers having mean diameters ranging from 3 microns to 16 microns, the density of the mass of fibers ranges from about 35 kg. to kg. per cubic meter, the granulometry of the hard particles ranges from about 0.10 mm. to 0.60 mm., with the proportion of solid particles ranging from about 3% to 15% of the total volume of the product.

References Cited UNITED STATES PATENTS 3,025,202 3/1962 Morgan et a1. 161-158 UK 1,354,025 9/1920 Coryeli 161162 X 2,972,554 2/ 1961 Muskat et a1 117-76 3,199,714 8/1965 Bodendorf et al. 22-0--9 3,515,624 6/1970 Garnero 161-158 X 3,562,370 2/1971 Shannon 264-1 12 WILLIAM A. POWELL, Primary Examiner US. Cl. X.R.