PIPE WITH INTERNAL COATING

Abstract

The invention relates to a fire protection pipe (1) provided with orifices (2) passing through the thickness of the pipe wall (3). According to the invention, the pipe (1) comprises a uniform internal coating (4) covering its entire internal surface (5). Figure for the abstract: Fig 1

Description

Title of the invention: PIPELINE WITH INTERNAL COATING Scope of the invention

[0001] The invention relates to the field of piping, and more particularly to piping intended for fire protection.

[0002] More specifically, the invention relates to pipes intended to be equipped with sprinklers capable of extinguishing or containing a fire by releasing an appropriate quantity of water. State of the art

[0003] In general, pipes intended for fire suppression systems have a substantial wall thickness, ranging from 2.6mm for pipes with a nominal diameter of DN25 to 4.5mm for pipes with a nominal diameter of DN200, in order to compensate for wear and / or corrosion inherent in the long service life of these pipes.

[0004] Although widely used, these pipes have several major drawbacks.

[0005] Firstly, these pipes corrode over their service life, typically 30 years. This corrosion accumulates over the years, thus progressively reducing the pipe's thickness. Therefore, the thicknesses typically used anticipate this corrosion.

[0006] In addition, even with annual cleaning of the pipes, some corrosion residues are difficult to remove and may compromise the proper functioning of the sprinkler heads.

[0007] Moreover, these pipes have a significant weight due to the wall thickness and their diameters, which implies a risk of musculoskeletal disorders for manufacturers and technicians installing fire-fighting devices, as well as an increased risk of accidents.

[0008] Finally, the dimensions of these pipes imply a large environmental footprint during their manufacture, and a large consumption of water when these pipes are installed and in use.

[0009] In fields other than fire protection, where pipes are not pre-drilled to accommodate sprinklers, it is known to coat the inner and / or outer face of the pipes with a coating that limits corrosion.

[0010] In the field of piping intended for fire-fighting devices, this technique is not used because the installation of sprinklers conventionally requires a Welding stage of the sprinkler receiving sleeves. This welding has the effect of at least partially detaching the internal lining.

[0011] The technical problem that the present invention aims to solve is therefore the reduction of the size of these pipes intended for fire-fighting devices, in order to overcome the aforementioned problems. Description of the invention

[0012] The invention proposes to address this technical problem by applying a coating to the entire internal wall of the pipe, leaving no area or portion of the internal surface uncoated. This coating, which prevents corrosion from forming in contact with the pipe material, allows for the construction of pipes with reduced wall thickness.

[0013] Thus, it is possible to produce pipelines with a reduced diameter and a reduced wall thickness without compromising the structure of the pipelines in use. Furthermore, the weight and environmental impact of these pipelines are considerably reduced, while ensuring the reliability of fire suppression systems over their service life.

[0014] The invention arises from the observation that, contrary to the technical prejudice of the person skilled in the art, it is now possible to fix sprinklers on pre-drilled pipes without risk of detachment of the internal coating, typically by using a solution such as that described in document WO2022 / 189738.

[0015] According to a first aspect, the invention relates to a pipe intended for fire protection provided with orifices passing through the thickness of the pipe wall.

[0016] The invention is characterized in that the pipeline comprises a uniform internal coating over the entire internal surface of said pipeline.

[0017] In this way, all areas of the internal surface of the pipeline exposed to corrosion are protected, eliminating any rust formation and any wear related to oxidation or usage stresses.

[0018] According to one embodiment, the internal coating is in the form of an aqueous phase paint, a solvent phase paint or an epoxy paint, so as to simplify the deposition of this coating and to use the anti-corrosive properties of certain paints.

[0019] Preferably, the internal coating has a resistance to cracking and / or peeling between 1mm and 10mm according to ISO 6860, and / or a resistance to impact by dropping mass between 300g / 50cm and 500g / 50cm according to NF EN 477.

[0020] In this way, the creation of the orifices through the wall of the pipe, which in practice does not require welding or deformation by thermal input / partial melting of the wall, does not compromise the integrity of the internal lining, which remains intact in the vicinity of said orifices.

[0021] Preferably, the orifices have a diameter suitable for the installation of a sprinkler head with a nominal diameter of DN15, DN20 or DN25, in order to be able to adapt to a plurality of types of sprinkler heads.

[0022] Preferably, the wall thickness of the pipe is between 1.8 and 2.9 mm, which implies a significant reduction in the weight of the pipes compared to the pipes usually used.

[0023] Preferably, the piping complies with the standard NF EN 10217-1, so as to be able to comply with the standards for fire protection devices.

[0024] Preferably, the pipe has an outside diameter between 33.7mm and 219mm.

[0025] Preferably, the pipeline is made of raw steel or stainless steel, so as to exhibit good fire stability in the event of a fire.

[0026] According to a second aspect, the invention relates to a method of making a pipeline according to the first aspect, and is characterized in that the orifices made in the thickness of the pipe wall are made after the internal coating has been deposited uniformly over the entire internal surface of the pipeline. Brief description of the figures

[0027] The invention will be better understood upon reading the following description, given solely by way of example, and carried out in conjunction with the accompanying drawings, in which identical reference numerals designate identical or analogous elements, and in which:

[0028] Fig. 1 illustrates a schematic perspective view of a pipeline intended for fire protection according to the invention;

[0029] Figure 2 illustrates a schematic cross-sectional view of a pipe at an orifice; and

[0030] Fig. 3 illustrates a schematic cross-sectional view of a portion of the pipe wall according to the invention at the level of an orifice. Detailed description of the invention

[0031] Figures 1 to 3 describe a conduit 1 intended for fire protection according to the invention.

[0032] The pipeline 1 according to the invention comprises an internal lining 4 and orifices 2 formed through the wall 3 of said pipeline 1. This pipeline can can either be made in one piece, or be made up of several sections welded together.

[0033] With reference to [Fig. 1], the internal surface 5 of the pipe 1 is entirely covered by a coating 4, which in practice takes the form of a layer of water-based, solvent-based, or epoxy paint. This coating 4 has a thickness of between 0.5 mm and 3 mm.

[0034] The wall 3 of the pipe 1 also has orifices 2 drilled at regular intervals along the pipe 1. These orifices 2 have a diameter suitable for the installation of a sprinkler head of type DN15, DN20 or DN25, at the choice of a person skilled in the art.

[0035] The wall 3 of the pipe 1 is made of metal, and more particularly of raw steel, also known as black steel. The pipe 1 can also be made of stainless steel, which has fire resistance substantially similar to raw steel. Other metallic materials such as copper or cast iron can be considered, without departing from the scope of the invention.

[0036] Pipe 1 has a nominal diameter DN between DN25 and DN200, which corresponds to an outside diameter between 33.7 mm and 219 mm. The different possible dimensions for pipe 1 according to the invention are as follows: DN25, DN32, DN40, DN50, DN65, DN80, DN100, DN125, DN150 and DN200, which correspond respectively to an outside diameter of 33.7 mm, 42.4 mm, 48.3 mm, 60.3 mm, 76.1 mm, 88.9 mm, 114 mm, 140 mm, 168 mm and 219 mm.

[0037] The pipes 1 according to the invention also have a wall thickness 3 of 1.8mm to 2mm minimum for pipes 1 of type DN25, DN33, DN40 and DN50; a wall thickness 3 of 2.3mm minimum for pipes 1 of type DN65, DN80 and DN100; and a wall thickness 3 of 2.9mm minimum for pipes 1 of type DN125, DN150 and DN200.

[0038] These wall thicknesses 3 represent a reduction in wall thickness 3 of 0.8mm to 1.6mm compared to the pipes 1 usually used in fire protection devices, namely the pipes 1 conforming to APSAD, EN12845 and / or FM standards.

[0039] With reference to figures 2 and 3, the orifices 2 pass completely through the wall 3 of the pipe 1 and the coating 4 present on the internal surface 5 of the pipe 1.

[0040] The orifices 2 are in practice made in the wall 3 after having coated the entire internal surface 5 of the pipe 1 with a protective coating 4.

[0041] During the drilling of these holes 2, there is no delamination, cracking, or crazing of the paint in the vicinity of the hole 2, such that no area of ​​the internal surface 5 of the wall 3 is exposed to corrosion. These holes 2 are preferably made without melting and without deformation by the application of thermal energy. such as by welding, by flow drilling or by friction, so as to preserve the good hold of the coating 4 and to avoid its detachment or even its destruction on the edge 6 of the orifice 2 drilled in the metallic wall 3 of the pipeline 1.

[0042] The resistance to cracking or peeling of the coating 4 is usually 3 mm according to ISO 6860, which is measured by bending a conical mandrel. Thus, the wall of the orifices 2 exhibits continuity between the metal wall 7 of the orifice 2 and the edges 8 of the orifice 2 cut into the coating 4.

[0043] The internal surface 5 of the pipe 1 is thus entirely protected by the coating 4, or even at the ends of the pipe 1. There is no discontinuity in the coating 4 over the entire internal surface 5 of the pipe 1.

[0044] The paint exhibits, in addition to its resistance to cracking, one or more of the following properties: a resistance to impact by falling mass of 400g / 50cm by direct or indirect impact according to standard NF EN 477, a Persoz hardness of 183 seconds at 24h according to standard NF EN ISO 1522, anti-corrosive properties and excellent water resistance.

[0045] The present invention thus enables the production of fire protection pipes 1 with a wall thickness 3 considerably reduced compared to pipes 1 commonly used in the prior art, and by eliminating corrosion phenomena on the internal surface 5 of the pipe 1. The present invention therefore reduces the physical risks incurred by manufacturers and technicians, while ensuring reliable operation of fire protection systems and reducing the environmental footprint. Advantageously, the present invention also reduces the production costs of the pipes 1.

Claims

Demands

1. Pipeline (1) intended for fire protection having orifices (2) through the thickness of the wall (3) of the pipe (1), characterized in that the pipe (1) comprises a uniform internal coating (4) over the entire internal surface (5) of said pipe (1).

2. Pipeline (1) according to claim 1, wherein the internal coating (4) is in the form of an aqueous phase paint, a solvent phase paint or an epoxy paint.

3. Pipeline (1) according to any one of the preceding claims, wherein the internal coating (4) has a resistance to cracking and / or peeling between 1mm and 10mm according to ISO 6860, and / or a resistance to impact by falling mass between 300g / 50cm and 500g / 50cm according to NF EN 477.

4. Pipeline (1) according to any one of the preceding claims, wherein the orifices (2) have a diameter suitable for the installation of a sprinkler head of type DN15, DN20 or DN25.

5. Pipeline (1) according to any one of the preceding claims, wherein the wall thickness (3) of the pipeline (1) is between 1.8 and 2.9 mm.

6. Pipeline (1) according to any one of the preceding claims, wherein the pipeline (1) conforms to standard NF EN 10217-1.

7. Pipeline (1) according to any one of the preceding claims, wherein the pipeline (1) has an outside diameter between 33.7mm and 219mm.

8. Pipeline (1) according to any one of the preceding claims, wherein the pipeline (1) is made of raw steel or stainless steel.

9. Method of making a pipeline (1) according to any one of claims 1 to 9, characterized in that the orifices (2) made in the thickness of the wall (3) of the pipeline (1) are made after the internal coating (4) has been deposited uniformly over the entire internal surface (5) of the pipeline (1).

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