DE29722652U1 - Fire protection mat - Google Patents

Description

BEETZ & PARTNERS ·' ·* ^! '·

Steinsdorfstraße ■ D-8O538 Munich "" *"" "* "European Patent Attorneys

Telephone (O89) 2959IO ^Fax (O89) 293963 _{founded 1926 by}

leiexö^O48 DipL-lng. R. BEETZ sen. (1897-1991)

671-52. 321G Dr.-Ing. R. BEETZ jun.

Dr.-Ing. W. TIMPE Dipl.-Ing. J. SIEGFRIED Prof. Dr.rer.nat. W. SCHMITT-FUMIAN Dipl.-Phys. Dr.rer.nat. C-M. MAYR Dipl.-Ing. A. PFEIFFER Dipl.-Ing. B. MATIAS

22 Dec 1997

Dieter Cremer
D-50259 Pulheim/Sinnersdorf

Fire protection mat

Various fire protection molded bodies made of so-called intumescent materials are already known, which foam up when exposed to heat and form a relatively dimensionally stable, fine-pored foam that fills open spaces and joints in a gas-tight manner and has high thermal insulation properties. These are always inherently rigid molded bodies, which are designed, for example, as plugs, stones or the like for sealing wall openings, as panels for lining or cladding housings, or as insulating layers in composite walls. To increase rigidity and other special properties, these known molded bodies can contain suitable fillers and/or reinforcements.

A generic fire protection mat is already known from DE-GM 8 008 190, which has a carrier made of preferably

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Expanded metal, a wire mesh or a glass fiber fabric with a large number of randomly distributed openings. This carrier is coated with a fire protection compound which forms an insulating layer of porous foam when exposed to fire. This mat must be attached to or around the bodies and products to be protected at a specified distance. The disadvantage is that it is not flexible enough for many applications and the coating tends to break when subjected to severe deformation, e.g. for the purpose of covering cables, lines, etc. In addition, the foam that forms from the coating mat when exposed to fire has relatively large pores in an irregular distribution, which significantly impairs the protective and insulating effect of this known fire protection mat. The relatively high rigidity of the mat also causes difficulties when laying or attaching it. A similar fire protection mat is known from US-A-4 255 483.

The subject of the invention is a fire protection mat which consists of a grid of heat-resistant and heat-resistant fibers, threads or strands which are coated with an intumescent material which, under the influence of heat, forms a shape-retaining, fine-pored insulating foam in the form of a carbon framework with a multiple increase in volume.

An essential aspect of the invention lies in the flexibility and bendability with a relatively high tensile strength of the fire protection mat according to the invention, which enables a tight sheathing of strands, such as cables, cable harnesses, pipes, etc., as well as a lining or covering of relatively complicated shaped components. It is also essential that the individual elements of the grid can be

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remain flexible and tensile at higher temperatures, so that the structure of the grid remains intact even in the event of a fire and can withstand relatively high mechanical stresses, such as increased tensile forces. These properties, in conjunction with the relatively low thickness of the mat of a maximum of a few millimeters, open up completely new application possibilities compared to known fire protection molded bodies.

To achieve an optimized fire protection effect, the structure of the grid including its mesh openings, the thickness of the coating of its elements and the foaming capacity of the intumescent material used are selected and coordinated so that in the event of a fire the mesh openings are largely filled by the developing insulating foam within a short period of time of just a few seconds and an essentially continuous, load-bearing foam layer is created that is several times thicker than the original mat thickness, in which the solid strands of the grid are embedded. This insulating foam layer provides heat insulation that is evenly distributed over the surface and thus effective fire protection for the component to be protected, whereby the retained tensile strength of the grid prevents cracks or breaks in the foam layer. Depending on the type of grid and the amount applied or the thickness of the coating, the spread of a fire can be prevented by 3 to 180 minutes. The heat transfer to the surface of the component to be protected is greatly reduced and the source of the fire is covered by the foam formed and prevented from spreading. Any halogenated acids that may be formed during the combustion of cable sheaths or other plastics are largely neutralized by the fine-pored foam and subsequent damage is also prevented.

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by corrosion can be kept within narrow limits. Furthermore, the strength of the fine-pored carbon foam has the further advantage that direct contact between conductors that are still carrying current and electrically conductive cable carriers is avoided even after the original cable insulation has melted or burned away. The open mesh of the grid guarantees sufficient heat dissipation from components that are moderately heated during normal operation, for example conductors under load, and thus prevents heat build-up, which can lead to the development of a fire in fully insulated components. Further advantages of the fire protection mat according to the invention are low weight, possible cutting with scissors or a knife, no contamination from paints or coatings during installation work, no covering work, no drying times, immediate functionality, exact compliance with required fire protection measures through controlled production, simple control of the fire protection measures carried out without the personnel carrying out the work needing any special specialist knowledge and finally its reusability after repairs to the respective component or other components. Of particular importance for the universal applicability of the fire protection mat according to the invention is its high flexibility and bendability, which enables tight coverings and linings of shaped bodies, such as cable harnesses, pipes, gutters or the like.

The manufacture of the fire protection mat according to the invention is also technically simple and cost-effective. Glass fiber fabrics are used as grids, either piece by piece or in continuous strips, which are coated, for example, by impregnation with the then flowable intumescent material. Glass fiber fabrics are particularly suitable if one of the pre-

a certain number of glass fibers are combined by a binding agent to form thread-like strands which form the weft and warp threads. Glass fiber fabrics with weft numbers of preferably 30/10 to 35/10 and with gross weights - including binding agent - of 150 to 220 g/m ² , in particular 190 g/m ² , are preferably used. The relatively break-resistant coating has elastic properties and a permanent adhesion to the glass fiber strands of the grid in order to guarantee the textile character of the mat and thus its easy handling and its universal application possibilities. The application quantities of this material after drying are preferably 700 to 1300 g/m ² , in particular 1000 g/m ² . A preferred type of intumescent material used as a coating contains, for example, ammonium polyphosphates, melamine phosphates together with polyhydric alcohols such as pentaerythritol or starch, as well as gas formers such as urea or melamine. Pigments for coloring, reinforcing fillers such as silicate-containing minerals, high-purity graphite powder as well as plastic dispersions, homo- or copolymer resins in significant amounts of over 50% by weight can be added to this insulating layer material.

Further features and advantages of the invention can be seen from the drawing and the following description of embodiments. They show:

Fig. 1 shows a partial section of a fire protection mat according to the invention in plan view;

Fig. 2 a· glass fibre grid of the fire protection mat in plan view,

Fig. 3 shows several of the possible applications of the fire protection mat according to the invention.

The fire protection mat shown as a part in Fig. 1 consists of the grid 2 shown in Fig. 2, which consists of glass fiber strands crossing at right angles. The individual glass fibers in each of these strands 3, 4 are held together by a so-called sliding test impregnation in the form of a suitable binding agent and processed into the grid fabric shown in natural size from thicker strands 4 and thinner cross strands 3, so that the grid has less flexibility in the direction of the strands 3 than in the cross direction. The glass fiber strands with the significantly larger number of glass fibers form the weft threads in the fabric shown in Fig. 2. The strands 3 forming the warp threads are designed as so-called leno threads, in which each strand 3 consists of two individual threads that are twisted together in such a way that each weft thread 4 is wrapped on both sides by one of these two threads at the crossing point.

The grid according to Fig. 2 is coated, for example, by impregnation with a fire protection compound with intumescent properties, whereby the fire protection mat 1 shown in Fig. 1 is produced. As can be seen, the mesh openings 5 of the grid have been retained in a reduced size, so that air and heat exchange is possible through these openings. Due to the applied thickness and the elastic properties of the coating material, the fire protection mat shown is flexible in any direction, whereby its flexibility in the transverse direction to the wider glass fiber strands 3 is naturally higher.

Fire protection mats of the type shown in Fig. 1 can be easily cut into pieces of the desired size for the applications shown in Fig. 3 using scissors or knives. Preferred applications of the fire protection mat are external cladding and internal lining of cable trays according to Fig. 3a and 3b, which can also be done in a similar way for cable ducts. Ventilation ducts and pipes can also be lined with the fire protection mats. Another preferred type of application is the cladding of electrical cables, cable bundles or cable harnesses shown in Fig. 3a to 3e, either in the form of a sleeve according to Fig. 3c, a single-layer spiral-shaped wrap according to Fig. 3d or in the form of a multi-layer spiral-shaped wrap according to Fig. 3e. The essential feature of the aforementioned applications is that the mat according to the invention can be arranged and attached to the objects to be protected without any gaps and in close contact.

The invention is not limited to the embodiments shown. Instead of the glass fibers used in this embodiment, other strong fibers based on minerals, metal, carbon or suitable plastics, as well as combinations thereof, can be used as strand-like elements of the grid.

Claims (3)

Expectations 1. Fire protection mat, consisting of a coarse-meshed glass fibre fabric as a heat-resistant carrier and a coating of a fire protection compound applied to the glass fibre fabric, which foams up to form a porous insulating layer when exposed to fire, characterized, that the glass fibre fabric (2) consists of weft threads (4) crossing at approximately right angles and warp threads (3) designed as leno threads, the weft threads (4) have a significantly larger number of glass fibres than the warp threads and the glass fibres in the threads (3 and 4) are held together by a binding agent, and that the coating consists of a crack-resistant plastic foam material which, when exposed to fire, forms a stable, relatively solid foam with a uniform, fine-pored structure. 2. Fire protection mat according to one of claims 1 to 3, characterized in that the mesh size of the grid (2), the thickness of the coating and the foaming capacity of the intumescent material forming the coating are coordinated with one another in such a way that in the event of a fire the mesh openings are filled with the fine-pored foam produced and a substantially continuous stable foam layer of considerably increased total thickness.. . . · 3. Fire protection mat according to one of claims 1 or 2, characterized in that the fire protection material contains heat-resistant fillers which strengthen the carbon skeleton. ■■'■'.■·.