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(11) | EP 0 035 817 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Fire-retardant wall |
| (57) The invention relates to a fire-proof wall comprising metal wall parts and a layer
of heat insulating material covering said parts. According to the invention said wall comprises: (1) an inner wall comprising gutter-shaped metal elements contacting one another in side-by-side positions and heat insulating material filling out said elements, (2) an intermediate partition covering the inner wall and comprising a layer of heat insulating material, and (3) a thermally deformable outer wall comprising adjoining, profiled metal elements, in a manner such that the heat insulating material in the gutters and that of the intermediate partition are located between the metal walls. |
[0001] The invention relates to a fire-proof wall comprising metal wall parts and a layer of heat insulating material covering said wall parts.
[0002] Hitherto it has been common practice to construct such a wall in the form of welded, heavy metal sheets together enclosing, for example, a working space. On the side of the working space insulating material was applied after the sheets had been welded together. This insulating material often contained asbestos. Apart from the fact that it has in the meantime been found that due to its very fine fibre structure asbestos may be hazardous to the staff, the known construction in itself has some disadvantages. The erection is a labour-intensive operation since the various wall parts have to be welded together, which is very time-consuming. It is furthermore necessary to use hoisting implements for disposing the wall elements because with the thickness of at least 5 mms these wall elements are very heavy and cannot be manipulated. Moreover, welding and subsequent application of the heat insulating layer give rise to considerable soiling lso that any apparatus present should be covered up. In addition, the applied layer is mechanically unprotected on one side. In the event of fire from the outside the insulating layer is not effective in preventing heating up of the main structure. It is a further problem that due to cold on the outer side of an erected wall condensation may take place on the inner side, which brings about the risk of corrosion particularly under off-shore conditions.
[0003] A further consequence of the aforesaid problems is that the installation of the known wall is expensive.
[0004] The fire-proofness of various walls is commonly expressed in terms of fire-proofness classes. The present case concerns the class H-120. A H-120 fire-proof wall satisfies the following requirement; it maintains its function with respect to the entity of structure and fire resistance for 120 minutes when exposed to a standardized time-temperature curve characteristic of a hydrocarbon fire (i.e. oil or gas combustion). By way of illustration temperature variations according to the following table may apply:
With this temperature variation on the fire-exposed side of the wall the rise of the mean temperature on the non-exposed side must not exceed 139°C, whilst otherwise the temperature must not increase by more than 180°C at any point including connecting points.
[0005] The invention has for its object to satisfy the said standards of Class H-120 whilst avoiding the aforesaid disadvantages of the prior art. For this purpose the invention provides a fire-proof wall of the kind set forth in the preamble which is characterized by
(1) an inner wall comprising gutter-shaped metal elements contacting one another in side-by-side positions and heat insulating material filling out said elements,
(2) an intermediate partition covering the inner wall and comprising a layer of heat insulating material, and
(3) a thermally deformable outer wall comprising adjoining, profiled metal elements,
in a manner such that the heat insulating material in the gutters and that of the intermediate partition are located between the metal walls.
[0006] In a practical embodiment the outer wall also comprises adjoining gutter-shaped metal elements extending side-by-side and heat insulating material filling out said elements and facing the intermediate partition.
[0007] The intermediate partition may comprise at least one heat insulating sheet held at least at the lower edge in one profiled metal bar, said one bar being fastened to the gutter-shaped elements. In this case the profiled metal bar may serve as an element stiffening the entire structure and as a fastening element.
[0008] The outer wall elements may have substantially the same cross-section as the inner wall elements and be disposed in off-set relationship thereto. This variant has the advantage that in this way the longest possible thermal bridge is formed between the side exposed to the fire and the side not exposed of the wall. It is thus ensured that the non-exposed side heats up as slowly as possible.
[0010] The invention furthermore relates to a wall element for use in a fire-proof wall, said wall element being provided, in accordance with the invention, with a corrosion-pre venting coating. This is advantageous since it is in this way avoided that, for example, during transport or storage in the open air corrosion occurs before the wall element is employed for building a wall.
[0011] A further advantage resides in a gutter-shaped wall element provided in advance with heat insulating material filling out the gutter.
[0012] The invention provides excellent protection against hydrocarbon fire of the background structure because the outer wall is thermally deformable. This wall is so thin that at high temperatures stress of the material will produce folds. As a result the stress of the material is eliminated so that no forces are exerted on the main structure and the tightness of the wall is assured. Preferably the ratio between the material thickness of the inner wall and the linear dimensions of non-profiled wall parts is at the most 1:150. A further advantage of this embodiment is that the wall elements are quite light-weight. The thickness is of the order of 0.75 mm or slightly more. Obviously, as compared with the conventional thicknesses of more than 5 mms this provides appreciable saving of material and costs.
[0013] In the wall according to the invention the inner wall serves as a gas-tight seal and as a damp-inhibiting skin.
[0014] In contrast to the conventional construction in which the wall parts are directly coupled with the supporting structure the supporting structure of the wall according to the invention is completely protected by insulating material, which further contributes to safety.
[0015] Recapitulating it is noted that the invention provides a fire-proof wall which satisfies at least the class H-120 standard particularly suitable for off-shore use, said wall allowing erection by the staff without the need for hoisting means and being appreciably cheaper than the known fire-proof walls.
[0016] The invention will now be described more fully with reference to a drawing showing in
Figure 1 an elevational view partly broken away of part of a first embodiment of a fire-proof wall in accordance with the invention,
Figure 2 a front view of a wall panel in a second embodiment of the invention,
Figure 3 a sectional view taken on the line III-III in Figure 2,
Figure 4 a cross-sectional view of a profiled loose wall element and part of an adjoining, further wall element,
Figure 5 a cross-sectional view of a gutter-shaped wall element filled with heat insulating material, and
Figure 6 a partial cross-sectional view of a wall element in accordance with the invention.
[0017] Figure 1 is an elevational view partly broken away of one embodiment of a wall in accordance with the invention. The Figure shows two skeleton parts of the supporting structure present i.e. an I-section beam 1 and an I-section rule 2 fastened to the former at an angle of 900. Vertical, gutter-shaped elements 3 are secured by means of rust-proof self-tapping steel screws 4 to the rule 2. The gutter-shaped elements 3 hold blankets of heat insulating material 5.
[0018] The side of the gutter-shaped elements 3 not visible in the Figure constitutes the wall surface of the working room to be enclosed by the wall.
[0019] On the open side of the gutters 3, that is to say, on the side of the heat insulating blankets 5 extends a further layer 6 of heat insulating material. On the other side thereof two profile beams 7,8 extend in a horizontal direction. The fastening screws 4 thereof extend across the heat insulating layer 6 and are tightened in the rims of the gutter-shaped elements 3. In this way the beams 7, 8 are secured in place, whilst at the same time the position of the layer 6 is fixed. On the top side the profile beams 7 and 8 carry the lower edge of further heat insulating layers 9 and 10 respectively. Their lower edge covers the top edge of the heat insulating layer 10 and a further heat insulating layer 11. In this embodiment an L-section beam 12 extends on the top side of the heat insulating layers 6 and 9 on the top of the construction. This L-section beam is welded by tie elements 30 to the rule 2. To the free, vertical head faces of the profile beams 7 and 8 and the L-section beam 12 are fastened profiled elements 13. To this end rust-proof, self-tapping steel screws are used likewise.
[0020] The profile of the gutter-shaped elements 3 and that of the wall elements 13 will be described hereinafter. In advance it is now noted that the joints between the inner wall elements 3 are filled out with cement during assembling in order to establish a gas- and vapour-tight seal. The edges of the outer wall elements 13, as will be explained hereinafter, are located at such a place relative to the final outer surface that they are satisfactorily protected against climatic conditions. With respect to the gas-tight seal of the inner wall it should be noted that it is common practice in the domains of use concerned to maintain excess pressure in the working spaces bounded by the walls in order to ensure that any transport of gas will invariably take place out of the working space to the outside rather than from the outer side to the interior.
[0021] In the embodiment shown in Figure 1 the heat insulating elements 5 and 9, 10, 11 consist of calcium silicate reinforced by fibres. For the heat insulating layer 6 is employed material commercially known by the tradename of "Promatect" containing cement, silicate and fibrous reinforcement.
[0022] By the construction described above and the aforesaid selection of material the wall according to the invention is found to largely satisfy the standards of class H-120.
[0025] The variant shown in Figures 2 and 3 comprises an inner wall of the same structure as in the embodiment of Figure 1. Figure 2 shows a frame for a wall comprising two vertical elements 14 and 15 and two horizontal elements 16, 17. The elements 14 to 17 have an L-section profile.
[0026] A skeleton beam 19 has connected with it an L-shaped angular element 18, to which is fastened the L-section element 14. A semi-gutter-shaped inner wall element 28 is fastened to the L-section element 18. This is adjoined by further wall elements 3 corresponding with the embodiment shown in Figure 1.
[0027] By means of rust-proof, self-tapping steel screws 20 across a "Promatect" layer 21 a plurality of rust-proof steel strips 22 are fastened to the head faces of the elements 28, 3. These rust-proof steel strips 22 serve on the one hand for fixing the position of the "Promatect" layer 21 and on the other hand for carrying the gutter-shaped outer wall elements 3 by means of rust-proof steel screws 23. With the outermost left-hand inner wall element 3 co-operates one limb of the L-shaped element 19 in a manner such that a satisfactory seal is obtained.
[0028] Figure 3 clearly shows the shape of the profile of the gutter-shaped elements 28, 3. From this Figure it will be apparent how the respective, complementary profile parts co-operate for obtaining a substantially flat wall surface.
[0029] The gutter-shaped elements 28, 3, like the gutter-shaped inner wall elements 3 of the embodiment of Figure 1, hold heat insulating sheets 5.
[0030] From the foregoing description it will be obvious that the vertical, broken lines of Figure 2 correspond to the joints between the adjacent elements 28, 3, 3, ... of the inner wall, whereas the vertical solid lines correspond to the joints between the outer wall elements 3.
[0031] Attention is drawn to the comparatively long heat transfer path from the outer wall to the inner wall, that is to say, from an outer wall element 3 through a screw 23, through a rust-proof steel strip 22, through a screw 20 to an inner wall element 28, 3.
[0032] In the embodiment shown in Figures 2 and 3 the head faces of the outer wall elements 3 have a profile for enhancing the rigidity.
[0033] Attention is drawn to the fact that the protruding tag of the outer wall elements 3 has a shape slightly differing from that of the inner wall elements 3. By providing a curved fastening part on each outer wall element 3 it is ensured that the heat transfer surface is minimized. In the area of the inner wall elements there is no problem of an undesirably large contact surface, since here all heat is transferred through the stainless steel screws 20.
[0034] Figure 4 is a cross-sectional view of an outer wall, profiled element 13. This Figure shows more in detail how the cut edges 24, 25 of a profiled element are protected against the weather conditions likely to expose the cut edges to corrosion after the wall according to the invention is assembled.
[0036] Figure 5 shows a loose wall element according to the invention which corresponds with the gutter-shaped elements 3 and is filled with a heat insulating sheet 5. For the sake of clarity the protruding tag of the gutter-shaped element 3 in this Figure is shown with a screw 23 corresponding to Figure 3.
[0037] Finally, Figure 6 shows a detail of a wall element according to the invention which comprises a metal sheet 26 provided on both sides with a corrosion-preventing coating 27. This coating may consist of PVC. It should be noted that the thickness ratios of Figure 6 and the other Figures depend, for example, on the requirements of mechanical strength. For example, it may be imagined that the sheet element 26 of Figure 6 has a thickness of about 1 mm, whereas the PVC coatings each have a thickness of about 0.1 mm.
[0038] The invention is not limited to the embodiments described. For example, the direction of length of the gutter-shaped elements of the inner wall and/or the outer wall in the embodiment shown in Figures-2, 3 may be horizontal rather than vertical. Moreover, other heat insulating materials than those mentioned above may be employed.
1. A fire-proof wall comprising metal wall parts and a layer of heat insulating material
covering said parts, characterized by
in a manner such that the heat insulating material in the gutters and that of the intermediate partition are located between the metal walls.
(1) an inner wall comprising gutter-shaped metal elements contacting one another in side-by-side positions and heat insulating material filling out said elements,
(2) an intermediate partition covering the inner wall and comprising a layer of heat insulating material, and
(3) a thermally deformable outer wall comprising adjoining, profiled metal elements,
in a manner such that the heat insulating material in the gutters and that of the intermediate partition are located between the metal walls.
2. A wall as claimed in claim 1 characterized in that the outer wall also comprises
adjoining gutter-shaped metal elements extending side-by-side and heat insulating
material filling out said elements and facing the intermediate partition.
3. A wall as claimed in claim 1 or 2 characterized in that the intermediate partition
comprises at least one heat insulating sheet held at least at the lower edge in one
profiled metal bar, said one bar being fastened to the gutter-shaped elements.
4. A wall as claimed in claim 2 characterized in that the outer wall elements have
substantially the same cross-section as the inner wall elements and are disposed in
off-set relationship thereto.
5. A wall as claimed in anyone of the preceding claims characterized in that the wall
elements are secured in place by means of self-tapping steel screws.
6. A wall element for use in a wall as claimed in anyone of the preceding claims characterized
by a corrosion-preventing coating.
7. A wall element for a wall as claimed in anyone of the preceding claims, characterized
in that the ratio between the material thickness of the inner wall and the linear
dimensions of non-profiled wall parts is at the most 1:150.
8. A gutter-shaped wall element for use in a wall as claimed in anyone of claims 1
to 5 characterized by heat insulating material filling out the gutters.