FR2468674A1 - - Google Patents

Abstract

The invention relates to continuously manufactured metal fiber mats, devices for their manufacture and various methods for their use. These mats consist of fibers 1, the length / diameter ratio of which can vary from 1000 to 2000. Each mat is maintained as a whole by the length and the surface structure of the fibers 1 obtained from the devices 2, as well as by the application in 5 of a bonding agent, these fibers being, during the manufacture of the mat, distributed in a uniform or disordered manner via flow guide walls 4, on a support surface. These mats can be used for reinforcing cement or concrete, as well as rubber and plastics, and find notable application in the manufacture of thin-walled articles or products.

Description

The present invention relates to mats or fiber mats

  devices designed for their manufacture and various

  dice of use of these mats. In addition, this invention also relates to

  an industrial process for the production of thin articles adapted to constitute walls and walls9.

  several reinforcing mats in metallic fibers.

  Many products are now being produced

  shot of a base material consisting of metal fibers. Among these

  known products include, among others, conventional fabrics constituting

  killed by a reticulated yarn, of the net or tulle type, and of wool of

  whose fibers are obtained, for example, by means of a turning process. Sintered fiber mats are another type of these

  known products which are manufactured by processes used in the indus-

  textile sorting. However, it is difficult and expensive to manufacture certain types of fiber mats, especially when one wishes to achieve

  and get a product of uniform quality.

  Accordingly, it is an object of the present invention to

  to obtain such a product of uniform quality in the form of a

  short metal fibers, using a process which consists of

  distribute these fibers evenly on a support surface, without this

  these have a definite orientation. By this manufacturing process se-

  invention, when a sufficient amount of fiber is thus distributed

  However, if these fibers are provided of sufficient length, they can intertwine or intertwine, thus binding to each other. In this manner, according to the present invention, it is possible

  hold a mat of metal fibers in which these fibers have a long

  but they are randomly oriented and distributed uniformly, in such a quantity that they are sufficiently linked together to be able to move Gre as a whole and without any great change in

  their continuous appearance, thus constituting a mat having a good co-

hesion as a whole.

  Another similar type of mat may be obtained, in accordance with

  in accordance with the present invention, by disproportionately distributing

  short and / or continuous on a support surface, until a

  thin and uniform layer is obtained.

  In addition, the cohesion of the mat is improved by the over-

  rough outer surface of the fibers or by the shape thereof. In addition

  these fibers can be flattened so as to produce hollows or corrugations, either at certain intervals or throughout their course.

  length, before they are distributed on a support surface.

  Another improvement in the cohesion can also be achieved by applying a binding agent on the distributed fibers, this

  agent which can be applied in the form of a finely dispersed

  on the entire mat so that the fibers are fixed or

  rusted together in the form of a well interwoven mat. It should be noted in this regard that a preferred binding agent should contain a large proportion of orthosilicate. Other types of bonding agents can be distributed in nets or continuous thin layers that bind the mat as a whole

  along its length. US Pat. No. 3,047,444, for this purpose, describes a

  bonded adhesive for non-woven materials applied in the textile industry. Another known method which makes it possible to bind the fibers together in a mat consists of. use ligation yarns that are sewn or woven into the mat and hold the fibers together

fixing in their neighborhood.

  In general, the known methods for attaching the fibers together to form a mat or carpet can be classified in the following categories: a) bonding by binder spraying or dipping in a bath b) bonding by application of nets or thin layers glue c) heating or melting the applied material d) building or weaving

  e) application of material to the fibers for delayed reaction

  solvents f) molding the mat by enclosing the fibers in a mold

  g) rolling and welding in seams or stitches.

  It should be noted that as regards point (c), a process

  mixes a certain proportion of plastic fibers,

  polypropylene, in the metal fiber mat and for example

  put these fibers together by heating under slight pressure.

  A mat produced in accordance with the present invention may

  advantageously be plated on a sheet of plastic material,

  pier or similar material, this sheet to stabilize the mat and maintain it as a whole. Using such a sheet

  as a support material, it is possible to wind the mat

  on a reel or use another kind of packaging. Moreover, it is possible to manufacture a mat made of oriented fibers in

  one direction, passing the fibers between two flat walls,

  hopper-like, to converge towards an opening of dis-

  narrow and elongated tribution, by which these fibers can be oriented in the same direction as the length of this opening. In another manner, by placing an electric coil in a suitable position, the

  fibers can be magnetically oriented when this coil is

  running. On the other hand, with a view to improving the manufacturing technique

  cation of the mats, the fibers may be subjected to a mechanical vibration

  that or electromagnetic. Moreover, by forming layers of

  rallies in different directions, their orientation can be made op-

  timum as desired. In addition, a mat or carpet can be preformed

  at the factory in a general configuration chosen for the product.

  In accordance with the invention, and with a view to ensuring a distribution

  In the case of uniform fiber production, a method used consists of feeding a wire and cutting it into sections of fibers at a fairly high speed. In a practical example, a feed speed of the yarn, between 8 and

  meters / second, is used to entralize a steel wire that is

  at this speed, by means of rotary knives, in sections or

  bres of definite length. Because of their flexibility and their

  The resulting fibers spontaneously intertwine to form a mat that can withstand a certain number of manipulations. An indentation or

  deformation of the wire makes it possible for the mat obtained to tolerate a change in

  rough pulation. It should be noted that a uniform distribution of fibers is facilitated

  by direct production of these on a support surface o

  they form a mat. Much greater difficulties are presented

  when the fibers are first stored in piles, then fed into a separating device, such as a rotating drum with holes or pins mounted radially inward, and finally discharged on said support surface. Note that a technique of this nature is

  described in GB 1 383 123. This patent indicates that straight fibers

  Mostly short, with a length determined by their diameter, that is to say an L / d ratio of 50 or so, could in practice be used. On the contrary, in

  implementation of the present invention, there is no such limitation

  The use of fibers and fibers having a length / diameter ratio of from 100 to 2000 is perfectly usable. Some products are dependent on this, such as mats or long fiber mats.

  A completely different process is to collect the

  by directing them in the same direction and storing them in a

  container, then unload them onto a support surface. This process

  curing the use of good fiber interlacing and can also

  the long fibers during temporary storage, with a view to

  uniform distribution on a support surface.

  Furthermore, in accordance with the invention, the adaptive equipment

  for the manufacture of fiber mats may include more than one

  fibers or devices for producing fibers from a yarn, which

  suitable lanes for distributing the fibers by spraying on a sheet, which may be moved alternately when the mat is being formed, the bonding or gluing agent being sprayed

  on this mat, then this one, as well as the sheet, being subjected together

  ble to a rolling operation. Alternatively, the fiber producing apparatus and the bonding agent spraying equipment are moved over the support or base surface on which the mat is formed, the latter remaining fixed. It should be noted that a faster rate of hardening by drying can be introduced in the treatment of the

  mat, for example, using any source of heating.

  The fibers are piled freely in the air under various

  concentration lumines, these volumes depending in part on their length / diameter ratio and, in part, their orientation. Randomly oriented fibers with a length / diameter ratio of about 300 contain approximately 98% air in their packing volume. On the other hand, a mat consisting of two layers of fibers, each of these layers having a uniform orientation of the fibers and these two layers being placed

  perpendicularly to each other, can be manufactured from

  more compact and have an air content of approximately 95-96%. Since the normal overall density of the fibers coincides quite well with the proportion of the desired volume in a composite material, it has been found that the fiber mats according to the present invention

  have a number of practical applications. -

  Indeed, in concrete technology, steel fiber mats are mainly used for the manufacture of walled articles.

  and, more particularly, those with two curved surfaces

  yees. Other important applications are the strengthening of the

  rubber and plaster, earth foundations, protection against

  erosion, construction of winter roads on ice by freezing

  in fiber mats, and the reinforcement of asphalt.

  A process practically applicable industrially, and

  form of the invention, will now be described according to the manufacture, inter alia, of plates, sieves, ducts, hulls of boats,

  storage tanks and the like, using a reinforcing mat

  is lying. This process consists of placing a fiber mat in a simple mold.

  solid or double-walled and impregnated with a concrete-based material. A preferred impregnation technique is to use a spray or pump device for the spraying of the concrete. Other techniques

  impregnation with concrete can be used, the simplest

  ple being the manual application of concrete by means of a trowel, a

  spreading water or similar tool. In other technologies, such as, for example, glass-fiber reinforced plastic, a fiberglass mat is impregnated in the same manner by spraying.

  on it of a resin, however, because at the same time the mat reinforces

  cement and the material used in concrete reinforcement techniques consist of inorganic materials, with large particles in the material and longer, thicker single fibers

  than those used in the techniques of strengthening the plastics material

  However, the manufacturing technique used differs greatly from one reinforced product to another. For example, the proportion by volume of glass fibers in the case of plastic is approximately 15 to 60%, whereas in the case of concrete, the proportion of steel fibers is

approximately 1 to 10%.

  The present invention also includes a vacuum treatment of the mold which may be single or double walled. By applying this

  surface treatment of the mold or a membrane and a surface of the mold.

  respectively, often consisting of a relatively impervious plastic sheet on a permeable sub-sheet, and subsequently removing the air so that the mass of concrete is simultaneously compressed,

  1 superfluous water is evacuated and the quality of the concrete is improved.

  SOE. In addition, the material and reinforcement are compressed together, if

  although the internal air pockets are suppressed and no expan-

  particularly strong steel fiber mat will not be feared.

  during the initial setting of the concrete. On the vertical walls or in

  slope, or when applied to a surface at the top, the

   Air intake can assist the retention of the material in place.

  In a molding operation made in a single-walled mold, an impermeable plastic sheet may, in some cases, be pressed against the newly molded surface. The air between

  the concrete and the sheet is then forced to evacuate using

  water or vibrating tools. By this method, the few fibers protruding from the concrete can be effectively compressed downwards. The sheet is then raised to separate it from the surface and then serves as a

  barrier against moisture when concrete is taken. The vibration operation

  improves the removal of the air contained in the concrete and also

  compaction of the latter around each of the fibers constituting the mat. This is of decisive importance for the resistance of the

  which has been defined in accordance with the present invention to

  dye very high values. Resistance to sagging which

  less the presence of a defect, exceeds the resistance to

  pressure of the concrete, is reached. This reinforcement technique is sim-

  implementation and insertion of reinforcement mats requires considerably less skill or experience than reinforcement

means of bars or lattices.

  A particularly advantageous technique, which is especially used for waterproof concrete, during the protection of the

  molding surface in the manufacture of boat hulls and tanks

  yoirs, is used in the following process. A molding surface is

  clothed or sprayed with a gelling agent which, when somewhat gelled, is subjected to a projection of fibers

  such as glass or steel fibers, or polypropylene

  lene, electrostatically charged to flatten the entire surface. The resulting fiber mat can then be pressed into the coating

  gelled. When this coating has hardened, the filler material is then

  against the latter, and if that material is made of concrete, it

  It is possible to use polymers to increase adhesion.

  A technique that can alternatively be used to obtain

  an increase in adhesion between the gelled coating and the concrete,

  consists of covering a single-wall mold with a conventional layer

  as hot-applied plastic material, such as a polyester or epoxy resin. This plastic is pigmented to the desired color. By this means, an outer layer, impermeable and colored (as well as brilliant),

  is obtained. When this layer has hardened, a new layer is applied

  to receive, before it hardens, a bonding material, which may be constituted by a steel fiber mat. This fiber mat

  is pressed against the plastic layer and concrete is then

  by, for example, spraying, until a good

  impregnation of this reinforcing mat is carried out, this impregnating

  possibly followed by vacuum treatment and

  vibration. Another method that can alternatively be used for

  get a good bond between the concrete and the gel product coating

  It involves spraying a thin layer, mainly composed of mineral compounds or polymers, on this coating before pouring the concrete. If a polypropylene cloth or other suitable material is applied before the mat is emptied, when casting on a single-wall mold, and if this is followed by the application of a foil

  conventional superior and inferior for vacuum treatment, a sec-

  surface can be obtained, free of any protruding fiber, and which gener-

  usually increases the quality of the product. It has been found during tests of

  load, that a finished product having a surface containing polypro-

  pylene and a steel fiber base had a strength and hardness

  (cracking resistance) of great value.

  It is obvious that the products and processes described above

  are not limiting. Thus, additive products, small aggregates

  gers, agglomerates and other materials may be used. The fiber mat can be fabricated with fibers oriented in the direction of the main tension due to the loads which determine the dimensioning. The products can be manufactured in sections or fractions using a single or double wall mold. In highly mechanized techniques, vacuum treatment, compression, vibration and impregnation of the

  may be made using permanent special equipment

  in a general installation.

  Note, moreover, that manufactured metal mats

  to serve as a means of liaison can be used for a certain number of

  different goals and, among other things, to serve as filters, electro-

  electrolytic treatment, acoustic panels, samples,

  cheureurs, silencers, etc.

  Other features of the present invention appear

  the following description, made in connection with the drawings below:

  joints, in which: - Figure 1 shows a form of fiber used in the manufacture of mats according to the invention - Figure 2 schematically shows a method used for the manufacture of a mat; FIG. 3 shows an oriented fiber mat obtained by implementing the methods according to the invention.

  FIG. 4 shows a variant embodiment of an incorporating mat

continuous fibers.

  As can be seen from these figures, the fiber represented

  1 is used in the manufacture of the mats and has a special shape adapted to contribute to the cohesion of the fibers, as well as to allow a suitable interlacing thereof, ensuring a good immobilization between them in the whole of the mat made at

  the apparatus shown in Figure 2. As shown in this figure,

  2, the fibers 1 produced by the

  2 and 3 pass through a distribution channel 4. This arrangement is adapted to implement one of the variants of the method according to the invention, by which a support sheet 3, moved in. one direction passes under the distribution opening of the corridor 4 and is covered with a uniform layer of fibers. This layer is then sprayed with bonding agent from the nozzles 5, which is then dried under the infra-red heating device 6. After this drying, the fiber mat 8 thus formed is rolled up to form a

roll 7.

  As shown in FIG. 3, a fiber mat

  longitudinally can be obtained by implementing one of the variants of the process according to the invention. Note that in this mat,

  the fibers are ligated with threads 9 which are threaded transversely

  to them. In FIG. 4, which shows an alternative embodiment of a longitudinally oriented fiber mat, it is seen that in addition to transverse ligation wires, this mat incorporates continuous longitudinal fibers 10 which have been threaded together with the formation of the

uniform layer of short fibers.

Claims (21)

R E V E N D I C A T I 0 N S CLAIMS   1.- Metallic fiber mat, characterized in that   its fibers are distributed more or less uniformly over an   face with a disordered orientation and are of sufficient length   to intertwine and intertwine, thus linking together   if to each other. 2. A mat according to claim 1, characterized by the fact that   - its fibers are linked together as a result of their external surface ru-   pigs and their adapted shape to immobilize and lock them in core more firmly between them.   3. A mat according to either of claims 1 or 2,   characterized by the fact that its fibers are, moreover, bound together by a bonding or bonding agent.   4. A mat according to any one of claims i to 3,   characterized by the fact that its fibers have hollows or corrugations   at any given intervals or over their entire length, these hollows or corrugations having been made by flattening or crushing these fibers before they are distributed in a uniform layer on said surface.   5. Mat according to any one of claims 1 to 4,   2,7 characterized by the fact that its fibers are linked together by an agent   which is suitable for constituting a surface protection agent. sky against corrosion.   6. A mat according to any one of claims 1 to 5,   controlled by the fact that its fibers are covered by a layer of   gn d; ture or collages whose thickness is less than 20% of their diameter.   7. A mat according to any one of claims 1 to 5,   taken by the fact that its fibers are bound together by an agent of   binding or gluing that was distributed in thin nets.   8. A mat according to any one of claims 1 to 5,   characterized by the fact that its fibers are bonded together by an agent of   bond containing orthosilicate.   9. batten according to any one of claims i to 5,   characterized by the fact that its fibers are bound together by a binding agent consisting of a product compatible with the material of which the mat must serve as reinforcement.   10. A mat according to claim 1 or claim 2, wherein   characterized by the fact that its fibers are bonded together by welding or by heating. 2468674   11. A mat according to either of claims 1 or 2,   characterized by the fact that its fibers are bound together by threads of   binding or ligation that are sewn, snuck or woven into the mat.   12.- Device adapted for the manufacture of a fiber mat having one or more of the features claimed in one of   any of claims 1 to 11, characterized in that it comprises   one or more apparatuses adapted to produce fibers, wherein the apparatus is arranged to distribute a uniform flow of fibers to a supporting sheet or strip   continually and directly below this flow, in order to   covered, that sheet or strip thus covered with a mat of fibers   both then wound on itself so as to constitute a mat roll whose fibers are lying one turn on the other, this device may also include a bonding agent applicator device, adapted to move over of the fiber layer that constitutes the mat made continuously.   13.- Device according to claim 12, characterized in that said bonding agent applicator device or bonding is arranged transversely to the scroll of the fiber mat and can be followed, downstream, by a device adapted to activate the hardening of   liaison officer before the mat is rolled up, the latter is   may be constituted by a heating device or by a device hardener agent tributor.   14.- Device according to either of claims 12 or   13, characterized in that it comprises a corridor adapted to the output of the fiber-producing apparatus, this corridor being constituted by at least two opposite fiber-guiding walls which terminate at their lower end, just above of the sheet or support strip, this corridor being designed so that the fibers, during their flow,   oriented and guided in their position on the said sheet of Harbor.   15.- Device according to either of claims 12 or   13, characterized in that it comprises an electrical coil arrangement   that, adapted to influence a mass of fibers in such a way that   they are oriented uniformly and, if necessary, vibrated.   16. A method of using fiber mats, such as   sold in claims 1 to 11 for the manufacture of products   or thin-walled articles, such as wallboard, sieves,   screens, storage tanks, hulls of boats and the like, by   using a cementitious binder material in a single or double mold 11 2 4 68 6 74   wall, characterized in that it consists in placing one or more   In the mold, these mats, intended to serve as reinforcements for the wall of the manufactured article, are then impregnated by means of shotcrete or otherwise distributed on the inner surface of the mats.   17.- Method of manufacturing articles or products with min walls   these according to claim 16, characterized by the fact that it consists of   to fart several times the operations of setting up successive mats, interrupted by operations of impregnation of these mats with concrete,   to obtain an article or product with a laminated wall.   18.- Method of manufacturing articles or products with min walls   These according to claim 16, characterized in that it consists in placing a molding plate or a membrane on the article or the molded product and, subsequently, in evacuating the air and the water contained in the latter, while   by at the same time subjecting it to a vibration operation.   19.- Method for manufacturing articles or products with min walls   these according to any one of claims 16 to 18, characterized by the   it consists in first coating the wall of the mold with a   plastic material such as epoxy resin, then harden this coating   by applying a layer of gelling agent and then applying   a new layer of coating and, before it is hard   cie, to apply on it a mat of steel fibers, this mat being then pressed maç-on it is pressed into this last layer of coating, a mass of concrete being then projected on the surface of this mat until that it is fully impregnated, after which 1 evacuation of the air and water contained in the concrete is carried out by means of said membrane and the wall of the mold respectively, at the same time   time that we undergo a vibration operation to this mass of concrete.   20.- Method of manufacturing articles or products with min walls   these according to any one of claims 16 to 18, characterized by the   it consists in first coating the wall of the mold with a   plastic material such as epoxy resin, then to harden this coating by the application of a layer of gelling agent and then to apply a new layer of gelling product and, before this layer is hardened, to apply on it a layer of bonding material, a steel fiber mat being then placed on the latter layer, and then depressed   in it and impregnated with a mass of concrete.   21.- Method for manufacturing articles or products with min walls   these according to any one of claims 16 to 20, characterized by the   It consists in applying a layer of gelling product on the surface. 12 2468674   face of the mold and then to project short fibers on this layer,   these fibers then being caused to straighten more or less perpendicularly   of the plane of this layer, by subjecting them to a treatment of electrostatic charge.