FR2916659A1 - DEVICE FOR APPLYING OR PROJECTING A MATERIAL OF HIGH DENSITY. - Google Patents

Abstract

This device for applying or projecting a layer of a high density material on a surface comprises: - a tank (1) receiving said material in which the latter is subjected to stirring by means of a stirrer (2 - a pumping system (3, 6) for conveying said material between the tank (1) and a projection or application member (7) .The agitator (2) is provided with means for: ▪ on the one hand, to maintain homogeneous the material to apply or to project, ▪ and on the other hand, to oppose the centrifugal effect of the corresponding agitation; The pumping system ensures a central and ascending pumping at the level of the device is provided with a return circuit (8) of said material extending between the projection or application member (7) and the tank (1), so that there is a permanent circulation in run in a closed loop.

Description

DEVICE FOR APPLYING OR PROJECTING A DENSITY MATERIAL

HIGH

  FIELD OF THE INVENTION The invention relates to a device for allowing the application or projection of a high density material. It relates more particularly to a device of the type in question intended to allow the application or projection of a liquid significantly loaded with metal powder, as part of the protection of surfaces against the corrosive action of the sea, and in particular hulls of ships and other offshore platforms, and in general, any surface subjected to the corrosive action of a fluid.

  PRIOR ART The coatings intended to be applied to hulls of vessels, with a view to protecting them against the corrosive action of the sea, but also against the encrustation of algae and other shells, have traditionally consisted of sauce or coating with a very high concentration of metal powder, typically copper, which can reach or even exceed 90% by weight of dry extract. This sauce also comprises a water-based or solvent-based epoxy resin which, when it polymerizes and hardens, thus making it possible to fix the coating sauce on the wall on which it is projected, in this case a shell ship or offshore platform beams. Due to this very high density, one must face a major problem, namely the projection or the application of this coating coating on the wall in question without risking the segregation between the liquid phase (epoxy resin and water or solvent) and the metal powder, which because of the very high concentration thereof, is likely to intervene very quickly, even almost instantly in the absence of agitation. Moreover, because of the very nature of this metal powder, the coating sauce has a particularly abrasive character.

  Finally, in order to facilitate the polymerization, the epoxy resin must be brought to a minimum temperature.

  To date, there is no known device capable of allowing the application or projection of such a coating coating in an efficient manner, on an industrial scale and at a reduced cost.

  It is precisely the object of the invention to provide such a device.

SUMMARY OF THE INVENTION

  This therefore relates to a device for applying or projecting a layer of a high density material on a surface, comprising: a tank receiving said material, in which the latter is subjected to stirring; a pumping system ensuring the conveyance of said material between the tank and the projection or application member.

  According to the invention: the agitator is provided with means for: on the one hand, homogeneously maintaining the material to be applied or sprayed, and on the other hand, to oppose the centrifugal effect of the corresponding agitation; The pumping system provides central and upward pumping at the tank; - The device is provided with a return circuit of said material extending between the projection member or application and the vessel, so that there is a permanent circulation during operation in a closed loop. In other words, the invention consists in subjecting the coating sauce to a particular and permanent agitation, and consequently in providing a central pumping of the medium thus agitated, thus making it possible to dispose at the level of the projection member. or to apply a homogeneous mixture permanently, and further prohibit any clogging of the pipes whose device is provided.

  According to the invention, the agitator comprises at least two sets of blades: a first set ensuring the proper agitation of the material to be applied; a second set, the blades of which are oriented in the opposite direction to the direction of rotation of the said first set, inducing, by virtue of this particular orientation, the displacement of the coating sauce in the central position relative to the axis; of revolution of the tank. According to another characteristic of the invention, the pumping system used is a horizontal membrane pump. It is even advantageously a pump with horizontal double membranes, such as for example marketed by the company GRACO under the reference TRITON 308. This pump ensures a flow rate of the coating source in the various pipes, that is to say that is to say especially between the tank and the member of projection or application, and back, at least 15 liters per minute.

  Said projection member is advantageously constituted by a nozzle operating with venturi effect operable by the user.

  According to the invention, it is mounted on the pipe upstream of the projection member, a heating member, in particular electric, capable of raising the temperature of the coating sauce to at least 30 C. The objective sought is to induce the polymerization of the epoxy resin contained in said coating sauce when it is a question of projecting an anti-fouling paint (Anglo-Saxon expression of the field, denoting a composition opposing the deposit and especially to the adherence of living organisms on a surface), anti-corrosive and anti-bacterial. Advantageously, the device further comprises a tank of water or of solvent, connected via a three-way valve to the main pipe extending between the tank and the projection member, and intended to allow the washing and rinsing the device after use, where the flow of water or solvent is again carried out by means of the aforementioned membrane pump.

BRIEF DESCRIPTION OF THE DRAWINGS

  The manner in which the invention can be realized and the advantages thereof will appear more clearly from the following exemplary embodiment given by way of non-limiting indication in support of the appended figures.

  Figure 1 is a schematic representation of the principle illustrating the device according to the invention. FIG. 2 is a diagrammatic representation of the agitator according to the invention. DETAILED DESCRIPTION OF THE INVENTION FIG. 1 shows a schematic view of the device according to the invention. In the present case, it has been shown in its mobile form, in that it is capable of being mounted on a trolley or a trailer, for example towed, or self-propelled, in order to allow a better fit of the positioning of the device. depending on the location of projection or application of the material. 10 In this case, the device in question is provided with the necessary means to ensure its autonomy, especially in terms of pneumatic or electrical power supply.

  The embodiment which will be described hereinafter relates to the more specific application of the invention to the more specific field of vessel hull coating by a particular paint having anti-fouling, anti-sticking properties, algae, anti-corrosive, even anti-bacterial.

  This device firstly comprises a tank 1 intended to receive the painting in question. This is basically composed of epoxy resin loaded to almost 90% by weight of dry extract of copper powder, in addition to a solvent or water.

  This mixture is agitated in the tank 1 by means of a stirrer 2, able to prevent the segregation between the copper powder, the epoxy resin and the solvent. This stirrer will be described in more detail in relation with FIG.

  In addition, a central suction tube, substantially axially with the stirrer, is inserted into a suction tube 3 opening into the lower zone of the tank, as can be seen in FIG. suction 3 is connected by a pipe 4 to a three-way valve 5, and more particularly to a diaphragm pump 6, in particular double horizontal membranes, which can be regulated. This pump is for example marketed by GRACO under the reference TRITON 308.

  This pump 6 feeds a projection member 7, for example consisting of a projection gun of the type marketed for example by the company ITW. This gun has a passage tube of the paint made of tungsten, to avoid the abrasion inherent in the flow of metal.

  The gun is provided with the necessary organs (especially pneumatic) capable of generating a strong venturi effect, which is implemented to ensure the application or projection of the paint when the gun trigger is actuated. This trigger allows the activation of a needle made of carbide, releasing access to the projection nozzle, the gun is equipped.

  This gun comprises a second channel for re-circulation of the paint through a pipe 8, returning said paint in the vessel 1, according to the circuit shown in broken lines in Figure 1, and that the nozzle is closed or not. In other words, the recirculation is permanent, the paint being taken from this recirculation during the phases of projection or application, that is to say, when the nozzle is open.

  In fact, because of the agitation in the tank 1, on the one hand and recirculation on the other hand, the paint is systematically in motion, thus avoiding any risk of segregation of its constituents and consequently the blocking of pipes 4 and 8.

  According to the invention, before reaching the level of the gun 7, the paint is heated by means of an electric heater 9, able to carry said paint at a temperature of 29 to 30 C, in any case at a temperature sufficient to induce the polymerization of the epoxy resin which allows its hardening, and corollary the effective fixing of the metal powder on the surface to be protected.

  This heater 9 is permanently activated, insofar as the duration of the mixture (in the Anglo-Saxon pot lift) allows it. Indeed, the epoxy resin consists of a mixture of a base and a hardener, whose caking time depends on the selected components. In this case, this duration is of the order of one to two hours.

  According to one characteristic of the invention, the stirrer 2 is capable first of all of providing the primary stirring function for which it is used within the vessel 1, and furthermore of concentrating the paint in central zone of said tank so that the suction by the suction tube 3 takes only the paint in a homogeneous composition, and whose quantity is determined by the pump 6.

  To this end, the agitator illustrated in FIG. 2 comprises, in the example described, two sets of blades respectively - lower stirring blades proper 10; - Concentration blades 11, which can be observed that they are oriented, and in this case, in a direction opposite to the direction of rotation of the lower blades 10.

  12 represents the motor ensuring the effective rotation of said stirrer. According to the invention, the tank 1 is provided with a cover 13, on which the stirrer 2 is mounted, and furthermore secured by a bracket 14 to an elevator 15, for example pneumatic. In doing so, it is thus possible to lift the lid when the device is not in operation by means of this pneumatic lift, and thus allow cleaning of the agitator, besides the tank periodically.

  The compressed air supply of the elevator is carried out by means of a thermal compressor 16, mounted in the case of the species on the mobile carriage.

  According to the invention, the three-way valve 5 mentioned above, communicates by its third way with a water or solvent tank 17, making it possible to ensure, always by means of the membrane pump 6, the cleaning of the pipes. 4 and 8, in addition to the tank 1 and the gun 7.

  The speed imposed by the membrane pump 6 is sufficiently high to avoid any risk of deposition, or even clogging of said pipe. In this case, it typically provides a flow is of the order of 20 to 30 liters per minute or more.

  It is thus conceivable that, with the device of the invention, it becomes possible to have a means of simple design, to allow the application or projection of a particular coating, according to specific quantities, which the we did not know how to do it effectively so far.

Claims (6)

  Apparatus for applying or projecting a layer of a high density material on a surface, comprising: - a tank (1) receiving said material, in which the latter is agitated by means of a stirrer (2); - a pumping system (3, 6) for conveying said material between the vessel (1) and a projection or application member (7), characterized in that the agitator (2) is provided with means on the one hand, to maintain homogeneous the material to be applied or to project, and on the other hand, to oppose the centrifugal effect of the corresponding agitation; in that the pumping system provides central and upward pumping at the vessel; in that the device is provided with a return circuit (8) of said material extending between the projection or application member (7) and the tank (1), so that there is a permanent circulation during operation in a closed loop.   2. Apparatus for applying or projecting a layer of a high density material according to claim 1, characterized in that the agitator (2) comprises at least two sets of blades: - a first set (10) ensuring the proper agitation of the material to be applied; a second set (11), the blades of which are oriented in the opposite direction to the direction of rotation of said first set, inducing, by virtue of this particular orientation, the displacement of the material to be sprayed or applied in a central position with respect to the axis of revolution of the tank (1).   3. Application device or projection of a layer of a high density material according to one of claims 1 and 2, characterized in that the pumping system is constituted by a horizontal diaphragm pump, preferably double horizontal membranes. 35   4. A device for applying or projecting a layer of a high density material according to claim 3, characterized in that the flow rate imposed by the pump is at least 15 liters per minute.   5. Apparatus for applying or projecting a layer of a high density material according to one of claims 1 to 4, characterized in that it comprises, upstream of the projection member (7), a heating member (9) for raising the temperature of the material to be sprayed or applied to at least 30 ° C.   6. Apparatus for applying or projecting a layer of a high density material according to one of claims 1 to 5, characterized in that it further comprises a reservoir (17) in water or solvent, connected via a three-way valve (5) to the main pipe (4) extending between the tank (1) and the projection member (7), and intended to allow the washing and rinsing of the device after use, the circulation of water or solvent being again, performed by means of the diaphragm pump (6).