Abstract:
A fire protection material ( 10 ) for protecting conduits ( 20 ), such as cable channels or pipes, has a matrix ( 11 ) which is formed of a plastic material shrinkable under action of heat and into which inclusions ( 12 ) of an active fireproof material are embedded.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to a fireproof material for protecting conduits such as cable channels or pipes in case of fire.  
         [0003]     2. Description of Prior Art  
         [0004]     Fireproof material of the type mentioned above is used, e.g., in the form of pipe sections, matting, or as strips for shielding conduits such as cables conduits, cable routes, insulated steel pipes, plastic pipes, etc., to squeeze and to completely cut off the latter in case of fire. For this purpose, the cables, conduits, routes, etc. mentioned above are lined or covered in a ring-shaped manner by the fireproof material in the area of a wall lead through.  
         [0005]     WO 99/18303 A1 discloses a method of protecting from fire of pipes and cable conduits from fire according to which various fireproof materials are arranged in layers around pipes or cable conduits in the area where they pass through a wall. For example, a strip-shaped intumescent material is placed around a pipe conduit initially and a layer of a material that shrinks when acted upon by heat is then arranged around this layer. In the event of fire, this layer of the shrinkable material contracts when heated and reinforces the squeezing of the pipe by the intumescent compound.  
         [0006]     The known solutions are disadvantageous due to the necessary expenditure on the mounting of the fireproof material, which requires a plurality of work steps.  
         [0007]     Accordingly, it is the object of the present invention to provide a fireproof material that is simple to mount and has an excellent fire-protection effect in the event of fire.  
       SUMMARY OF THE INVENTION  
       [0008]     According to the invention, this and other objects of the present invention, which will become apparent hereinafter, are achieved by providing a fireproof material having a matrix of plastic material which can shrink when acted upon by heat and in which inclusions of an active fireproof material are embedded. The shrinkable plastic materials are, e.g., polyolefins, fluoropolymers and elastomers whose molecules are crosslinked, e.g., by radiation polymerization, while as the active fireproof material, e.g., an intumescent, ceramizing or ablative material can be used. This step provides a homogeneous fireproof material which can be arranged at a conduit in only one work step and can be sealingly shrunk over this conduit by heating.  
         [0009]     It may be advantageous in technical respects of manufacture when the inclusions are strand-shaped so that the fireproof material can be produced by a continuous method, e.g., as strip goods. This strip-shaped fireproof material can then be wrapped around conduits and subsequently sealingly shrunk thereon.  
         [0010]     Naturally, the inclusions can also be shaped in any other manner, e.g., be made spherical, granular, or rod-shaped.  
         [0011]     The fireproof material can advantageously be tubular. In this way, it can be pulled directly over a conduit and then shrunk onto it.  
         [0012]     An adhesive layer can be advantageously applied to a flat side of a strip-shaped fireproof material, and the fireproof material can be preliminary fixed on a conduit by the adhesive layer prior to shrinking.  
         [0013]     Further, the fireproof material can advantageously also be formed as a ductile or kneadable mass. This mass can be used in a flexible manner also for conduit lead-throughs that are difficult to access and can be pressed into very narrow gaps. By a subsequent heating, the kneadable fireproof material can then be sealingly shrunk over the cable. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]     Further advantages and features of the invention will become apparent from the following description when read with reference to the drawings. In the drawings:  
         [0015]      FIG. 1  is a cross-sectional view of a ring-shaped fireproof material according to the present invention, arranged around a conduit;  
         [0016]      FIG. 2  shows a view similar to that of  FIG. 1  with the fireproof being shrunk on the conduit;  
         [0017]      FIG. 3  shows a cross-sectional view of a strip-shaped fireproof material according to the invention;  
         [0018]      FIG. 4  shows a cross-sectional view of the strip-shaped fireproof material along line IV-IV from  FIG. 3 ; and  
         [0019]      FIG. 5  shows a cross-sectional view of a fireproof material in the form of a kneadable mass. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0020]      FIG. 1  shows a fireproof material  10  in the form of a tubular section which, in this case, is arranged around a conduit  20  and is formed as a pipe. The fireproof material  10  has a matrix  11  of a plastic material that is shrinkable under the influence of heat. Shrinkable plastic materials of this kind are, for example, polyolefins, fluoropolymers, and elastomers whose molecules are crosslinked, e.g., by radiation polymerization. Inclusions  12  of an active fireproof material, e.g., an intumescent, ceramizing or. ablative material, are incorporated in the matrix. Materials of this kind are, e.g., expandable graphite, vermiculite, sodium silicate, chemically intumescent materials (e.g., mixtures of APP, melanin, pentaerytrite). These inclusions  12  can be, e.g., granular, spherical, rod-shaped, strand-shaped, fibrous, or the like. The dimensions of the inclusions  12  can range from a fine dispersion (the size of dust particles) to one or more millimeters. In the case of strand-shaped or fibrous inclusions  12 , their length corresponds approximately to the axial length of the tubular fireproof material  10 .  
         [0021]     In  FIG. 2 , the tubular portion of fireproof material  10  is shrunk on the conduit  20  by a local heat treatment (e.g., heating to approximately 70° C.). The material of the matrix  11  is shrunk by the heat treatment to approximately 70%-25% of its original dimensions so that the fireproof material now tightly contacts the surface  21  of the conduit  20 .  
         [0022]     In case of fire when the material is heated, e.g., to above 100° C., the inclusions, e.g., of an intumescent material, swell and squeezes the conduit  20 . This prevents the spread of fire.  
         [0023]     In  FIG. 3 , the fireproof material  10  is formed as strip-shaped flat material. The matrix  11  is again formed of a plastic material which is shrinkable under the influence of heat and in which are incorporated inclusions  12  of active fireproof material, described above. An adhesive layer  13  is arranged at a flat side  14  of the fireproof material  10 . The fireproof material  10  can be fixed at least in a preliminary manner to a conduit by this adhesive layer  13 . As can be seen in  FIG. 4 , the inclusions  12  are strand-shaped in this case and extend approximately parallel to the longitudinal extension of the fireproof material  10 . In the mounted position of the fireproof material  10 , the latter compasses a line  20  analogous to  FIG. 2 .  
         [0024]     According to  FIG. 5 , the fireproof material  10  can also be formed as a kneadable or deformable mass and has a matrix  11  of a plastic material which is shrinkable when acted upon by heat and which is also elastically deformable. Inclusions  12  of an active fireproof material are again arranged in this matrix  11  as was already described above.  
         [0025]     The mass according to  FIG. 5  can be used in a very flexible manner and can also be applied in very narrow structural spaces.  
         [0026]     Though the present invention was shown and described with references to the preferred embodiments, such are merely illustrative of the present invention and are not to be construed as a limitation thereof, and various modifications of the present invention will be apparent to those skilled in the art. It is, therefore, not intended that the present invention be limited to the disclosed embodiments or details thereof, and the present invention includes all variations and/or alternative embodiments within the spirit and scope of the present invention as defined by the appended claims.