JPH069410B2 - How to prevent the spread of cable - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for preventing spread of a cable by using a sheet produced from a foamed fireproof composition.

[Prior Art] A cable or a power cable is usually installed at a predetermined location by using a so-called ladder-shaped cable supporting device. Then, the cable power cable is provided with a measure to prevent the spread of the fire in case a fire occurs after the cable is installed in a predetermined arrangement. As a typical method for this purpose, there is a method in which a flame spread prevention tape is wound around the surface of a cable installed in advance.
In this method, a means for continuously and continuously winding the wound long cable on the cable is adopted.

Thus, when winding the fire spread prevention tape around the cable in such a state, the cable is lifted from the pedestal supporting the cable from below, and the tape wound in advance in a ring shape is passed under the cable. I had to wrap it, I had to lift the cable to a considerable height,
It is extremely troublesome and time consuming, and its workability is extremely poor.

In addition, in the fire protection measures of this type of cable, in addition to the requirement that workability is excellent, there are two requirements that the disaster prevention performance is excellent and that the current capacity is not reduced as much as possible. is necessary.

Currently, there is no fireproofing device that satisfies the above two requirements and is excellent in workability, and this development is strongly desired.

[Problems to be Solved by the Invention] A problem to be solved by the present invention is to develop a method for preventing the spread of a cable that can meet the above-mentioned conventional demands. More specifically, it has excellent disaster prevention performance and current capacity. The purpose is to develop a method for preventing the spread of power cables, especially power cables, which has extremely low workability and which does not reduce the temperature as much as possible.

[Means for Solving Problems] Means for solving the problems are (a) the specific thermal resistance value produced from the foamed fireproof composition is 600 ° C. · cm / W or less, and Fire spread prevention sheet (1) provided with a double-sided adhesive layer (8) on at least part of one side
(B) The surface of the cable (2) is overlapped with the longitudinal ends (3), (3 ′) of the sheet (1-1) and the double-sided adhesive layer (8) is on the inner side. Wind it vertically so that it will be on the (cable side), and (c) Wrap the same flame spread prevention sheet as in (a) above on it in the same way as one layer, leaving both ends (7) in the circumferential direction. It is solved by turning (d) and then forming an impermeable layer (10) from above, and (e) finally fixing both ends (7) in the circumferential direction of (c) above.

[Operation and Configuration of the Invention] The inventor of the present invention has continued research to develop a fire protection measure for this type of cable, especially power cable, but has succeeded in developing an excellent means in this research. This means is to use a sheet produced from (A) foamed fireproof composition as a fire spread prevention sheet.

(B) This fire spread prevention sheet has a specific thermal resistance value of especially 60.
Must be 0 ° C / cm / W or less (However, the specific thermal resistance value at this time is the value measured by the following method.
SA-1412 was used to measure the thermal conductivity, and the intrinsic thermal resistance was calculated from this value according to the normal conversion method).

(C) The above-mentioned sheets having a thickness of 2.8 mm to 5 mm are sequentially laminated vertically on the surface of a one- or two-layer cable, and (D) the above-mentioned sheet is a sheet (1) as shown in FIG. ), (1)
..On the surface of the cable (2) and its longitudinal ends (3),
(3 ′) ··· are vertically stacked so that they overlap, and the overlapping portion is the fixing fastener (4),
(4) It is a means consisting of being fastened with '.

It is to be noted that vertically stacking the above sheet on the cable means that the sheet (1) is attached along the length direction (5) of the cable (2) as shown in FIG. It is a method in which it is wound around, and then sequentially repeated in the length direction of the cable (2).

The present inventor has continued to further research on this already developed fire protection means, but in this research, for a so-called small outer diameter cable in which the diameter of the cable is not particularly large,
Succeeded in developing a fire protection method with good workability,
The present invention is completed here.

In the method of the present invention, the above-mentioned (A)-
Although the means (D) is adopted, this means is further improved in the following points.

One of the improving means is a fire spread prevention sheet of the above (A).
As the thickness of (1), a thinner one is used, and this is lapped (longitudinally) at least twice, preferably 2 to 4 times.

As a second means, on the outermost layer sheet of the above-mentioned (A) sheet (the outermost sheet in the case of being lapped in 2 to 4 times, hereinafter referred to as the outermost layer fire spread prevention sheet),
To further form an impermeable layer with or without some margin. At this time, as the outermost layer fire spread prevention sheet, a fire spread prevention sheet on which the water-impervious layer (10) is previously provided may be used.

As the third means, the outermost flame spread prevention sheet
As shown in the figure, it is wound by leaving both ends (7) in the circumferential direction and fixing both ends (7) in the circumferential direction. Is to use the ingredients.

Fourthly, of the above-mentioned means (D), the means for fixing the overlap portion with the fixing fastener is not adopted.

In the method of the present invention, since the thin sheet is used as the fire spread prevention sheet (1), even if the cable has a small diameter, it can be easily wound with good adhesion without repulsion. Can be done. Further, since the double-sided adhesive layer (8) is provided on at least a part of one side of the fire spread prevention sheet (1), when the adhesive sheet is wound a plurality of times, each of the adhesive layers is
Since it is adhered by (8) and exhibits a sufficient initial adhesive force, each sheet can be surely overlapped wound without separating, and as a result, the fourth characteristic described above is exhibited and the sheets are tightened one by one. There is no need to tighten with tools.
Then, such a thin sheet is applied a plurality of times, preferably 2 to
By wrapping the sheet four times, compared to the case where one sheet is wound, the effect of further improving the fire spread prevention effect can be obtained even if the entire sheet has the same thickness.

In the method of the present invention, since the impermeable layer (10) is used,
It is possible to prevent moisture from entering from the outside.

In addition, in the present invention, the outermost layer spread prevention seal
As shown in the figure, since the both ends (7) in the circumferential direction are wound and the both ends (7) are fixed with a stapler, a clip, etc., the operation is extremely simple.

The method of the present invention will be described below in accordance with the procedure with reference to FIGS.

First, in the method of the present invention, the fire spread prevention sheet (1 of 1 is vertically attached to the surface of the cable (2), and the end portion of the sheet in the vertical direction is
(3), (3 '), etc. are overlapped with each other and a plurality of times, preferably 2 to 4 times, are vertically wound and overlapped. However, the outermost flame spread prevention sheet (1-2) is wound so that both ends (7) in the circumferential direction remain, as shown in FIG. At this time, as a method of winding the fire spread prevention sheet (1), as described above, the fire spread prevention sheet (1) is vertically attached and is wound 2 to 4 times.

As the fire spread prevention sheet (1) used at this time, for example, as shown in FIG. 4, a double sided adhesive layer (8) is formed on at least a part of one side of the fire spread prevention sheet (1). When the sheet (1) is used as the outermost layer fire spread prevention sheet, it should be shielded with or without a margin (9) on the other side of the sheet (1) as shown in FIG. Water layer
It is convenient to use the one formed with (10). Of course,
It is not always necessary to use the water-impermeable layer (10) previously formed on the sheet, and this water-impermeable layer (10) may be separately laminated.

The double-sided pressure-sensitive adhesive layer (8) does not necessarily have to be formed on the entire surface of the fire spread prevention sheet (1), and may be within a range in which sufficient initial adhesiveness is exhibited during winding. The means for forming the double-sided adhesive layer (8) is not particularly limited, and it is convenient to use a double-sided adhesive tape, for example. A vinyl chloride adhesive film is usually used as the water-blocking layer (10). This impermeable layer (10)
Is usually formed on the entire outer surface of the outermost flame spread prevention sheet, but a margin (9) may be left partially.

The fire spread prevention sheet (1) used is made of a foamed fireproof composition. At this time, the foaming fireproof composition is preferably a composition containing a foaming substance having a property of foaming and preventing fire by heat when a fire occurs. Specific examples include a polyhydric alcohol such as pentaerythritol, a foaming agent such as melamine, preferably a fine melamine that passes through 100 mesh, a flame retardant dehydrating agent such as ammonium polyphosphate, and halogen in an amount of about 25 to 50% by weight. Examples of the composition include a composition containing a halogen-containing polymer as a main component and an expansive inorganic material such as graphite or vermiculite mixed with a polymer substance. This sheet is preferable because it has a self-fusing property.

As another embodiment of the present invention, FIG. 6 shows an example of a fire spread prevention method in the case of a plurality of cables. However, FIG. 6 shows an example in which two sheets are used as the fire spread prevention sheet (1), the inner one is called the inner layer fire spread prevention sheet (1 of 1), and the outer one is the outermost layer as already mentioned. Fire spread prevention sheet (1-2). First, an inner layer fire spread prevention sheet (1-1) is vertically attached and sequentially wound around the surface of the cable (2) so that the double-sided adhesive layer (8) is on the cable side. The longitudinal ends (3) and (3 ') are in an overlapped state as shown in FIG.

Then, put the outermost sheet (1-2) on both ends (7) in the circumferential direction.
In the same manner as above, the water-impermeable layer (10) is formed. Fix both ends (7) with fasteners (11) such as staples or clips. In addition, in FIG. 3 and FIG. 6, (12) shows a cable pedestal.

As the fixing tool at this time, a stapler, a clip and the like can be exemplified as preferable ones, but particularly preferable ones are
It is a commercially available fixture as shown in FIG. 7. Thus, all the surfaces of the sheets laminated on the cable are impermeable layers.
It will be covered with (10).

For reference, the features of the fireproofing means of the method of the present invention will be slightly described below.

Regarding the above-mentioned basic configuration (B) of the fire prevention means, by setting such a specific thermal resistance value,
It is possible to suppress the decrease in current capacity to a minimum, and it is possible to suppress the decrease to such an extent that there is practically no problem. Originally, winding a fireproof tape around a cable tends to reduce the current capacity. It is said that one of the factors is that an air layer is formed between the cable and the tape, but in this fire prevention means, it is especially necessary to use the fire spread prevention sheet (1) as described above. In particular, in combination with treating this sheet by a method such as (C) above, even if there is a slight air layer, it is possible to stop the reduction of the current capacity within a range where there is substantially no hindrance. I can. Further, in this means, the fire spread prevention sheet (1) is vertically attached to the cable 2 to 4 times in sequence. By performing the construction as described above, excellent disaster prevention performance can be imparted, and the reduction in current capacity can be suppressed to a level at which there is substantially no hindrance.

In this way, spread the fire prevention sheet (1) to the vertical end (),
By overlapping (3 ') and fixing both ends (7) in the circumferential direction of the outermost layer fire spread prevention sheet with fixtures (11), excellent disaster prevention performance can be imparted and the conventional tape This makes it possible to work with an extremely simple method compared to the winding method.

[Advantages of the Invention] By adopting the method as described above, it is possible to extremely easily realize disaster prevention of a large amount of cables in a cave and small-diameter power cables, and with good workability, and the effects are immeasurable. Absent.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a drawing showing an example of a construction method for forming a fireproof structure, and FIG. 2 is a drawing for explaining a vertical attachment construction method adopted in the construction method of FIG. . Further, FIG. 3 is an explanatory view showing an example of the method of the present invention, and FIGS. 4 and 5 are drawings showing an example of a fire spread prevention sheet. FIG. 6 is a drawing showing a construction method using another fire spread prevention sheet of the present invention. FIG. 7 is a drawing showing an example of a fixture. (1), (1 ') ・ ・ ・ Fire spread prevention sheet (2) ・ ・ ・ ・ ・ ・ Cable (3), (3 ′) ・ ・ ・ End of fire spread prevention sheet (4) ・ ・ ・ ・ ・ ・Fixing fasteners (5) ・ ・ ・ ・ ・ ・ Cable length direction (6) ・ ・ Winding direction of the fire spread prevention sheet (7) ・ ・ ・ ・ ・ ・ Ends of outermost layer sheet ( 8) ・ ・ Double-sided adhesive layer (9) ・ ・ ・ ・ ・ ・ Margin (10) ・ ・ Water impervious layer (11) ・ ・ Fixing tool (12) ・ ・ ・... Cable pedestals

Claims (2)

[Claims] (A) A specific heat resistance value produced from a foamed fireproof composition is 600 ° C. · cm / W or less, and a double-sided adhesive layer (8) is provided on at least a part of one side thereof. Place the fire spread prevention sheet (1 of 1) on the surface of the (2) cable (2) and the longitudinal end of the sheet (1).
(3), (3 ') ... are overlapped, and the double-sided pressure-sensitive adhesive layer (8) is wound vertically so that it is on the inner side (cable side). Use the same fire spread prevention sheet (1-2)
One layer is wound in the same manner, leaving both ends (7) in the circumferential direction, (d) Next, the water-impervious layer (10) is formed on it, and (e) Finally, the circumference of (c) above. Secure both ends (7) in the direction. A method for preventing the spread of a cable, which is characterized in that 2. An impermeable layer (10) according to claim 1.
A method for preventing the spread of fire of a cable, wherein a water barrier layer (10) is formed in advance on the spread prevention sheet of (c) as a means for forming the spread.