EP2253354B1 - Method for manufacturing an element of a fire protection network using automatic sprinklers and associated element - Google Patents

Description

The invention relates to fire protection systems by sprinkler system (or sprinklers).

Such a network comprises pipes (or antennas) conveying a fluid, typically water, under pressure, and automatically performing a sprinkling on a firebox when the ambient air reaches a predetermined temperature and / or when fumes are detected. .

Conventionally, and as illustrated on the figure 1 an element 100 for a sprinkler fire protection network comprises a pipe 10 provided with a plurality of sprinklers 20 fixed to the pipe 10 by screwing into sleeves 30.

The pipe provided with the sleeves is made (i) by drilling a generally cylindrical tube 10, to form a plurality of orifices of a given diameter (depending on the type of sprinkler 30 used), (ii) tapping sleeves 30 the diameter of the thread of the sprinklers 20, and (iii) notching and welding of the sleeves 30 on the pipe 10 opposite the orifices. The sprinklers 20 are then screwed into the sleeves 30, in order to obtain an element 100 of sprinkler network.

These elements have already been proven and are now widely used in fire protection systems of buildings.

However, they remain perfectible from an economic point of view, their manufacturing process being consumer including manpower and material.

The known elements may also be subject to leakage if they are subjected to intensive use or are provided with low quality welds, thus reducing the effectiveness of the fire protection network more or less inconveniently (leaks, pressure drop in the pipes, etc.). Moreover, such leaks can convey microbes, which is particularly contrite in buildings such as hospitals or pharmacies.

The document DE 44 17 446 discloses a method of manufacturing a pipe for a sprinkler array in which holes are bored in a pipe by means of a conical tool, and then the material pushed back into the grooves is deburred (with removal of material) holes by means of a conventional drill, before tapping the holes thus obtained to obtain threaded bushings.

The document DE 28 26 141 describes a dry sprinkler network comprising an elastic membrane adapted to contain granules. During a fire, the membrane is pierced so as to release the granules.

The document GB 2,069,386 discloses a method of manufacturing a pipe for a sprinkler array in which a hole in a pipe is deformed with a conical tool, and the resulting holes are tapped to obtain threaded bushings.

The document US 5,174,500 describes a sprinkler array element comprising a valve adapted to block or allow a flow of water to pass.

Finally, the document US 1,906,953 discloses a method of manufacturing a pipe in which an opening in the wall of a thin and malleable pipe is formed using a tool that rotates rapidly to generate heat by friction and plastically deform the metal.

The invention therefore aims to provide a sprinkler fire protection network element whose risk of leakage are reduced, and which is also a lower manufacturing cost.

Another object of the invention is to provide a method for manufacturing a sprinkler fire protection network element and an associated pipe, which is more reliable and less expensive to produce.

For this, the invention provides a method of manufacturing a sprinkler fire protection network element according to claim 1. In this way, the pressure losses inside the pipe are reduced thanks to the limitation of the overflow in the internal volume of the pipe of a part of the base of the sprinkler when this one is fixed on the pipe.

• l'étape i)b. comprend les sous-étapes suivantes :
  • i)b.1) réaliser les douilles par perçage avec déformation plastique de la paroi ; et
  • i)b.2) tarauder les douilles ;

Some preferred but non-limiting aspects of the method of manufacturing a pipe according to the invention are the following:

• step i) b. includes the following substeps:
  • i) b.1) making the sleeves by drilling with plastic deformation of the wall; and
  • i) b.2) tapping the bushings;

• le taraudage des douilles est réalisé avec déformation plastique de la matière formant les douilles ;

Such a method thus makes it possible to obtain a pipe according to the invention which is devoid of sleeves, thus avoiding the risks of leakage and reducing its manufacturing costs.

• the tapping of the sleeves is made with plastic deformation of the material forming the sleeves;

• l'étape i)b.1) est réalisée par fluoperçage ;
• l'étape i)b.2) est réalisée par fluotaraudage ;

The implementation of tapping and / or drilling by plastic deformation with heating of the material forming the sleeves makes it possible to obtain a pipe provided with sleeves integrally and integrally with the pipe, adapted to maintain in a sealed manner the sprinklers.

• step i) b.1) is performed by flow-through;
• step i) b.2) is performed by cold forming;

The cold-forming and the fluo-piercing are processes respectively for drilling and tapping, in which the material is plastically deformed by heating by virtue of the friction of the tool against the wall of the pipe. They can be easily implemented on conventional drill press machines by simple adaptation of the drilling or tapping tool. They are therefore particularly adapted to the implementation of the method according to the invention and do not require substantial modifications of the machines commonly used in industry.

The prior step of drilling pilot holes with removal of material in the wall reduces the amount of material flowing during the manufacturing process, and thus the size of the sleeve inside the pipe.

• La figure 1 est une vue en perspective d'un élément d'un réseau de protection contre l'incendie par asperseur conforme à l'art antérieur ;
• La figure 2 est une vue en perspective d'un élément d'un réseau de protection contre l'incendie par asperseur conforme à l'invention ;
• La figure 3 est une vue en coupe d'une douille de la conduite de la figure 2 ;
• La figure 3a est une vue en coupe de la douille de la conduite de la figure 3, dans laquelle un asperseur a été monté selon un exemple ne faisant pas partie de l'invention ;
• La figure 4 est une vue en coupe de la douille d'une deuxième forme de réalisation d'un élément d'un réseau de protection contre l'incendie par asperseur selon un exemple ne faisant pas partie de l'invention ; et
• La figure 5 est une vue en coupe de la douille d'une troisième forme de réalisation d'un élément d'un réseau de protection contre l'incendie par asperseur conforme à l'invention.

Other aspects, objects and advantages of the present invention will appear on reading the following detailed description of preferred embodiments thereof, given by way of nonlimiting examples and with reference to the appended drawings in which:

• The figure 1 is a perspective view of an element of a sprinkler fire protection network according to the prior art;
• The figure 2 is a perspective view of an element of a sprinkler fire protection system according to the invention;
• The figure 3 is a sectional view of a sleeve of the conduct of the figure 2 ;
• The figure 3a is a sectional view of the sleeve of the conduct of the figure 3 , in which a sprinkler has been mounted according to an example not forming part of the invention;
• The figure 4 is a sectional view of the socket of a second embodiment of an element of a sprinkler fire protection network according to an example not forming part of the invention; and
• The figure 5 is a sectional view of the socket of a third embodiment of an element of a sprinkler fire protection system according to the invention.

As shown on figures 2 and 3 an element for a fire protection network according to the invention comprises a pipe 10 and at least one sprinkler 20 conventionally formed of a head 21 and a threaded base 22.

The pipe 10 comprises a generally cylindrical wall 11 made of a metallic material, for example steel, and a plurality of sockets 12 threaded to the diameter of the threads of the bases 22 of the sprinklers 20.

For example, the pipe 10 is a metal pipe of circular section, in which a plurality of sockets 12 integrally formed were formed and tapped.

Thus, unlike the conventional elements 100, no welding is necessary in order to obtain a fire protection network element, since no sleeve 30 is welded to the pipe 10.

Element 1 according to the invention is manufactured as follows:
First provided is a pipe 10 formed of a generally cylindrical wall 11 closed metal, for example a steel pipe. Such conduct may be manufactured on site, or in a separate location.

The sleeves 12 are made by plastic deformation of the wall of the pipe 10. For this purpose, the wall 11 is heated locally at the location where it is desired to form a sleeve 12, and the heated material is rejected. in order to form the sleeve 12. The sleeve 12 has thus come integrally with the pipe 10.

In a preferred embodiment, the sockets 12 are made by flow-piercing. A pulverizing tool is then used, such as a drill press equipped with a conical drilling tool whose outer surface is rough and rotated at a high speed. When the conical tip of the tool comes into contact with the surface of the wall 11, the material is simultaneously heated, drilled and plastically discharged radially and axially, without removal of material, as illustrated in FIG. figure 3 . There is therefore no external supply of heat, the material being heated only by the friction between the tool and the wall 11 of the pipe 10. The resulting sleeve 12, resistant and in one piece with the pipe is then constituted by an extra thickness of substantially cylindrical material surrounding the opening formed during the operation.

The portion discharged outwardly during the flow can be leveled to obtain a smooth contour line, or kept as is.

Practically, the rotational speed of the flow-forming tool and the axial force exerted on it are adjusted according to the duration of the required operation, the material of the wall of the pipe and its thickness, or of the desired piercing quality.

Prior to the realization of the sleeve 12, a pilot hole by a conventional drilling process with removal of material is carried out in order to reduce the amount of material flowing during the drilling process by heating and plastic deformation. The bushing 12 is then of reduced length relative to the bushing obtained without a pre-hole, which makes it possible to reduce the bulk of the bushing 12 inside the pipe 10 and thus the pressure drops.

The sleeves 12 are then threaded in the conventional manner, or by plastic deformation of the material.

For example, each bushing 12 is made by the cold forming technique using a suitable tap which delivers the material at the sleeve 12 and uses it to form a net 13, again without removal of material. By this method, the structure of the metal is not weakened, which makes it possible to obtain a threaded bush 12 having a better surface state and better mechanical strength than traditional tapping methods.

According to another embodiment, possible in the case where the thickness of the wall of the pipe 10 is sufficiently large, the sockets 12 are obtained by drilling an orifice through the wall of the pipe 10 according to a drilling method conventional and then cold-forming, so as to create a threaded bushing 45 integral material from the area of the pipe surrounding the orifice obtained.

It is therefore sufficient for at least one of the drilling and tapping steps to be carried out by plastic deformation of the wall 11, to obtain a threaded bushing 12 formed integrally and formed directly from the wall 11 of the pipe 10.

The deformation is carried out hot to the extent that the material is heated by friction of the tool against the wall 11 of the pipe 10.

In a particularly advantageous embodiment, both the drilling and tapping step are performed by plastic deformation of the wall 11, for example by flow-forming and cold-forming, so as to reduce the amount of material used, the production time. , labor, etc. while obtaining a pipe 10 of high quality, provided with a sleeve 12 having an excellent surface and excellent mechanical strength.

Finally, the sprinklers 20 are fixed by screwing their threaded base 22 into each of the threaded sleeves 12 so as to obtain the element 1 according to the invention.

The sprinkler 20 is a conventional sprinkler, for example of the bulb type, made of steel.

According to a variant not forming part of the invention as illustrated on the figure 4 , in order to reduce the pressure drops due to the overflow in the internal volume of the pipe 10 of a part of the base 22 of the sprinkler 20 when this latter is fixed on the pipe 10, specific sprinklers can be produced. 20a having a reduced axial base length 22a. For example one can realize bases 22a having an axial length of the order of 5 to 10 mm.

According to the invention, as illustrated on the figure 5 between the base 22 of a conventional sprinkler 20 and the bushing 12 is an upstanding ring 30 which, again with the aim of reducing the pressure losses, limits the axial overflow distance of the base 22 into the interior space of the pipe 10.

Of course, the present invention, defined in the claims, is not limited to the embodiments described and shown, but the skilled person will be able to make many variations and modifications.

Claims (5)

1. A method for manufacturing a network element for protection against fire by sprinklers comprising the steps consisting of:

   i) manufacturing a duct (10) by means of a method comprising the steps consisting of:

   a. providing a metal duct (10) including a generally cylindrical closed wall (11); and

   b. performing in the duct (10) a series of threaded inserts (12) integrally formed by plastic deformation of the wall (11), by flow-drilling and/or flow-tapping,

   which method for manufacturing a duct further comprises, prior to the production of the series of threaded inserts, a step of drilling pilot holes with removal of material in the wall (11),

   ii) providing a series of sprinklers (20) each including a base (22) and a spray head (21);

   iii) placing an enhancement ring (30) on each base (22) of sprinklers, then

   iv) fastening each sprinkler (20) through its base (22) in a respective insert (12) of the duct (10).
2. The method according to claim 1, wherein step i)b. comprises the following sub-steps:

   i)b.1) making the inserts (12) by drilling with plastic deformation of the wall; and

   i)b.2) tapping the inserts (12).
3. The method according to any of claims 1 and 2, wherein the tapping of the inserts (12) is made with plastic deformation of the material forming the inserts (12) .
4. The method according to any of claims 2 or 3, wherein step i)b.1) is carried out by flow-drilling.
5. The method according to any of claims 2 to 4, wherein step i)b.2) is carried out by flow-tapping.

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