FR2643291A1 - Improvement to devices for spraying jets of liquid for the purposes of cleaning and/or cutting - Google Patents

Abstract

Device for spraying at least one jet of liquid under a high pressure, greater than 500 bar, for the purposes of cleaning a surface or of cutting a material, and the device is characterised in that it consists, on the one hand, of a cylindrical body 1 forming a nozzle holder connected via a pipe 2 to a source of pressurised liquid, the said cylindrical body defining an internal chamber 5 extending the end of the said pipe, the said chamber including a plurality of openings 6, 7 towards the outside, and, on the other hand, of a plurality of removable nozzles 15, 16 each of which can be locked in place in one of the said openings.

Description

The present invention relates to a device for permitting under yield conditions and. improved efficiency and with considerably increased profitability, the projection of one or a plurality of liquid jets intended to participate in a cleaning operation, in particular industrial cleaning or cutting of materials.

The present invention will be described more particularly in connection with its application for cleaning operations, in particular industrial cleaning, within capacities, volumes, tanks and more especially still pipes, tubes or conduits.

Such volumes and pipes are frequently fouled and cluttered with deposits, in particular of mineral nature (caicaria or other) and these deposits constitute a brake in the movement of the liquid conveyed by the pipe, consequently reducing the flow rate and the yield of the installation.

It is therefore necessary to carry out from time to time and at regular intervals or not, cleaning operations aimed at eliminating the parasitic deposits which have accumulated on the walls.

It should however be understood that the invention is not limited to this application and will be usable each time a jet of liquid is used to attack a material with a view to piercing it, destroying its overall structure and eliminate it, either for the purpose of evacuating a parasitic deposit, or in order to carry out a cutting or a drilling in the structure itself.

In the presently known art, jets of liquid, in particular of water, are used under high pressure to be sprayed from treated steel nozzles.

The operating pressure generally used is of the order of 600 to 800 bars for cleaning operations, while it can exceed 2000 bars and reach 000 bars for material cutting operations.

It is understood that an essential condition for obtaining a maximum yield from the projected jet is its compactness and its homogeneity.

Insofar as the jet remains coherent and attacks the material at a precise point, allowing a punctual and focused action on an extremely reduced surface, the physical decomposition action of the material undergoing this force is more effective and therefore allows quickly destroy the structure of the attacked material.

However, experience shows that the nozzles currently used and made of treated steel, whose '' orifice is sim? Lemens drilled, deliver a I; emerging in the open air qJ rapidly loses its cohesion and which remains homogeneous only over a relatively short length of the order of 6 to 10 mm; beyond & the jet begins to disperse so that it attacks the material on a larger surface thus losing part of its effectiveness since the force is dispersed on an impact surface which becomes more and more important as measure as the distance between the nozzle and the attacked surface rises.

Experience also shows that the commonly used treated steel nozzles are rapidly degraded and eroded by the force of the liquid streams which pass through them; so that by a cumulative process, this degradation of the surface state of the nozzles leads to pressure drops and the formation of vortex movements within the jet which are a new cause of dispersion of the jet and of reduced efficiency.

The present invention relates to improvements made to water spraying devices and which make it possible to considerably improve the efficiency, profitability and yield of both cleaning and cutting operations.

To this end, the invention relates firstly to a device for projecting at least one jet of liquid under high pressure, greater than 500 bars, for the purpose of cleaning the surface or cutting material, and the device is characterized in that it consists on the one hand of a cylindrical body forming a nozzle holder connected by a pipe to a source of pressurized liquid, said cylindrical body defining an interior chamber extending the end of said pipe, said chamber comprising a plurality of openings to the outside and on the other hand a plurality of removable nozzles capable of being immobilized each in one of said openings.

It can be seen that according to this first characteristic of the invention, a mobile device consisting of a nozzle holder is used, in which the individual nozzles are removably mounted, thereby allowing the interchangeability of the nozzles after wear.

The use of a "nozzle holder" capable of receiving removable nozzles also makes it possible to adapt, as required, the individual nozzles which will be used on each head, in particular to adapt the dimensions and characteristics of the projected jets, dimensions which will be determined by the characteristics, in particular the outlet sections of said individual nozzles.

Finally it is still possible, thanks to the invention and using the nozzle holder thus specified, to produce a projection head capable of emitting a plurality of jets in diverging directions with preferably a resultant force capable of ensuring progression of the head inside the treated volume, the multiplicity of openings provided on the head making it possible to adjust not only the flow rate and the characteristics of the individual jets but also their number and their direction.

It is indeed possible according to the invention to put on the head forming nozzle holder thus produced a number of nozzles corresponding to the needs while some of the openings will simply be neutralized.

 According to another characteristic, the device thus comprises in key one and preferably a plurality of shutter members able to stay in place on one or more of said neutralized and closed openings without these openings comprising projection nozzles.

According to another characteristic, said openings provided on the nozzle holder include threaded bores and the nozzles themselves, as well as the shutter members, are provided with an external thread allowing them to be fixed by screwing in said bores.

According to yet another characteristic, the nozzles each consist of a removable sleeve capable of being engaged and immobilized in one of the openings of the cylindrical body forming a nozzle holder, and each nozzle comprises at its base a crown whose internal orifice defines the section passage of the jet and said crown is made of a material with a high hardness coefficient such as ceramic, natural and / or artificial stone.

For example, said crown is made of sapphire.

According to another characteristic, said openings are distributed in helices along the cylindrical body forming nozzle holders.

According to yet another characteristic, this cylindrical body forming a nozzle holder has a front wall closing off its distal end and this wall has openings for receiving projection nozzles.

More specifically, this front wall is of generally frustoconical shape and it forms an angle between 45 and 600 with the internal face of the cylindrical internal wall.

According to another characteristic, the openings arranged on the cylindrical body and receiving said nozzles are oriented in divergent directions and preferably in radial directions from the center of said body.

According to yet another characteristic, the frustoconical front wall has a central opening coaxial with the director of the cylindrical chamber forming nozzle holder.

According to another characteristic, the openings are arranged in such a way that the overall reaction thrust resulting from the addition of the forces constituted by the jets coming from the set of nozzles is exerted in a direction coaxial with the median axis of said chamber. and in a direction opposite to the connection on the liquid inlet and supply pipe.

According to yet another characteristic, the interior surface of the chamber within the cylindrical body forming nozzle holder is machined until a surface condition of less than 0.05 microns is obtained.

More especially still, each nozzle formed by a cylindrical sleeve, is dimensioned so as to come to bloom at the level of the external wall of the cylindrical body forming nozzle holder, on the one hand, and at the level of the internal wall of this cylindrical body d 'somewhere else.

According to yet another characteristic, each cylindrical sleeve is dimensioned so that the length of the internal bore in this sleeve represents li to 7 times the internal diameter of the crown defining the passage section of the liquid jet, and this tubular bore of the sleeve is greater than said passage section.

According to yet another characteristic, the sum of the surfaces of the nozzles, placed on the cylindrical body forming a nozzle holder, is between 2.9 and 0.1 times the internal surface of the chamber.

 Finally, the invention relates to a use of the preceding device * .er.v specified for a cleaning operation and it is characterized in that the speed in the supply line is between 0.6 and 0 , 4 times the speed of this displacement of the liquid jet within each unit nozzle, for a supply pressure between 600 and E33 bars.

Other characteristics and advantages of the invention will emerge from the description which follows and which is given in relation to embodiments presented by way of nonlimiting example and with reference to the accompanying drawings.

FIG. 1 represents a perspective view of the nozzle holder according to the invention with the bare openings.

Figure 2 shows the nozzle holder of Figure 1 in which the nozzles are put in place.

3 shows a sectional view of the nozzle holder of Figures 1 and 2 with placement of the nozzles in the receiving openings, it being specified that Figure 3 does not represent a section in the same plane but shows nozzles which are situate in different planes this for better clarity of the invention.

Figure 4 shows a sectional view of an individual nozzle.

FIG. 5 represents a perspective view of the nozzle of FIG. 4.

According to all of the figures, it can be seen that according to the invention, a cylindrical body 1 has been provided forming a nozzle holder connected to the end of a tube 2 for the arrival of the pressurized liquid, this tube 2 preferably being flexible for allow movement of the nozzle holder 1 in pipes or capacities that are difficult to access.

The nozzle holder 1 consists of a main cylindrical body 3 and ends in a distal wall, opposite the tubular supply 2; this distal wall 4 closes off the end of the tubular body 3 forming the nozzle holder t and it is of generally frustoconical shape.

The interior of the nozzle holder 1 defines a chamber 5 into which consequently the supply pipe 2 opens, and this chamber communicates with the outside, through the wall 3 by openings 6,7 (FIG. 3) or 8 , 9.10 (Figure 1).

Similarly, openings 71, 12 are arranged on the distal plot of cylindrical shape; and the latter ends with a front part offering a flat 13 which is itself crossed by an opening 14 thus arranged coaxially with respect to the director of the cylindrical body 3.

While FIG. 1 represents the nozzle holder in the naked state, FIGS. 2 and 3 represent this same nozzle holder furnished with a plurality of individual nozzles 15,16 respectively (FIG. 3), and 17,18,19 (figure 2).

Figures 4 and 5 show respectively sectional and perspective views of these individual nozzles which can be placed in the openings.

It is seen from Figure 2 that the openings are before a carefully distributed, to obtain a balance in the distribifiicr. openings avoiding creating zones of weakness in the cylindrical wall, along a helical line ong ce la paroI 3.

 As is shown in FIG. 4, each individual nozzle is made up of a sleeve 20 internally defining a bore 21 which constitutes a tube for protecting the jet 22 at its outlet from the passage section 23 defined by the crown 2+.

This crown is made of a material with a high hardness coefficient, for example ceramic and preferably natural or synthetic stone such as sapphire.

This ring 24 defines by its internal diameter the passage section 23 and therefore the characteristics of the jet 22.

The use of a crown defining this passage section made of material with high resistance to physical corrosion, makes it possible to improve the longevity of each individual nozzle r.zse in place on the nozzle holder.

The internal bore 21 also constitutes a protective structure which prevents the formation of vortices in the peripheral threads of the jet when the latter emerges in the open air. -
As seen in Figure 5, the outer wall of the sleeve 20 has a thread 20b which therefore allows the engagement and immobilization of the nozzle in its receiving opening 7t This thread 20b stops near the top 20a of the nozzle (outlet of the jet) allowing the nozzle to be blocked in its housing.

The opening 7,7 ', internally has a thread corresponding to the thread 20b of the nozzle so that the nozzle is easily engaged and immobilized in its housing formed by this opening 6,7 (Figure 3) or' 7 '(Figure 4 )
In order to facilitate the positioning of each nozzle, the head or crown 20a of this nozzle has a diametrical slot 20c which facilitates the tightening of the assembly by the play of a screwdriver.

We understand that it is easy to replace the nozzles on the nozzle holder head as and when they wear out similarly it is easy using the nozzle holder of appropriate diameter depending on the capacity in which it must work , to mount on this nozzle holder individual nozzles with characteristics, in particular of suitable passage sections determining as a function of a certain pressure, the exit speed of the liquid jet, this being controlled by the nature of the material to be attacked in its structure by; cleaning jets.

It is therefore possible from a single head to provide adaptations according to each need.

Likewise, it is not necessary for all the openings of the head to receive a nozzle and it is possible to adjust and modulate the jets dispersed from the head as required by neutralizing for example some of the openings by the installation of '' a shutter screwed purely and simply into this opening.

More specifically, it is provided in the context of the invention that the openings and therefore the directions of the nozzles placed in the openings, be shouted with a bifurcating diverging from a central position inside the chamber 5, the orientations of the nozzles and corresponding openings being provided generally radially.

It is in particular provided that the openings are arranged so as to provide a majority of openings directed towards the rear.

 Thus one obtains a thrust resulting from the joint addition of the forces corresponding to the cumulated jets, exerting in the direction of the front that is to say towards the frontal because thus ensuring a progression of the head traveling to the Interior of the pipe, as part of the cleaning of a tubular structure; the supply line 2 progressing following the nozzle holder head.

The inner wall of chamber 5 is machined so as to obtain a perfectly polished surface state, of the order of 0.03 microns, so as to avoid any source of parasitic vortex flow at the displacement of the threads. liquid along this wall inside the chamber 5. It is further provided that the section of each nozzle is flush and extend the inner wall of the nozzle holder.

In addition, according to the experiments and tests carried out by the applicant, it has appeared that within each nozzle, the diameter of the bore 21 must be slightly greater than the passage section 23 so as to allow the flow of the jet. 22 avoiding any friction and any dispersion.

The length of the bore 22 is preferably between 4 and 7 times the diameter of the passage section 23.

While it has also been defined by the tests and experiments of the inventor that the cumulative surface occupied by the base of the individual nozzles must represent approximately one tenth of the total surface of the interior wall of the chamber 5.

The device of the invention has been described more particularly in connection with its application for industrial cleaning operations, pickling, removal of parasitic deposits, etc.

 Ih can however be used under the same conditions for cutting operations and in this case the nozzle holder head will preferably be equipped with a single axial nozzle, the other nozzles being neutralized, shutters being placed in the openings .

In the case of using the device during cleaning, provision has been made for operation with a supply of liquid, for example water, such that the speed in the supply channel 2 is between 0.6 and 0.4 times the speed within each unit nozzle, the jet exit speed being of the order of 300 meters per second; the supply pressure is between 600 and 800 bars.

Claims (13)

1 - Device for projecting at least one jet of liquid under other pressure, greater than 500 bars, for the purpose of surface cleaning or cutting of material, and the device is characterized in that it consists of a part of a cylindrical body (1) forming a nozzle holder connected by a pipe (2) to a source of pressurized liquid, said cylindrical body defining an interior chamber '5) extending the end of said pipe, said chamber comprising a plurality of openings (6,7) to the outside and on the other hand a plurality of removable nozzles (15,16) capable of being immobilized each in one of said openings.  2 - device according to ia claim 1, characterized in that it thus comprises at least one and preferably a plurality of shutter members capable of being ms in place on one or more of said openings neutralized and closed without these openings projection spray nozzles. 3 - Device according to ia claim 1 and / or claim 2, characterized in that said openings (6,7,8,9,10) provided on the nozzle holder fl, comprise threaded bores and the nozzles themselves- same (15,16,17,18), as well as the shutter members, are provided with an external thread allowing their immobilization by screwing in said bores.  4 - Device according to one of claims 1 to 3, characterized in that the nozzles (15,16,17,18) each consist of a sleeve (20j removable capable of being engaged and immobilized in one of the openings of the cylindrical body forming nozzle holder, and each nozzle has at its base a crown (24) whose internal orifice defines the passage section of the jet and said crown is made of material with a high coefficient of hardness such as ceramic, natural stone and / or artificial. 5 - Device according to one of claims 1 to 4, characterized in that said openings (6,7,8,9,10) are distributed in helices along the cylindrical body forming nozzle holder. 6 - Device according to one of claims 1 to 5, characterized in that this cylindrical body (1) forming nozzle holder has a front portion (4) closing off its distal end and this wall has openings for receiving projection nozzles. 7 - Device according to one of claims 1 to 6, characterized in that this front section (4) is of generally frustoconical shape and it forms with the inner face of the cylindrical inner wall an angle between 45 and 600. 8 - Device according to one of claims 1 to 72 characterized in that the openings arranged on the cylindrical body and receiving said nozzles are oriented in divergent directions and preferably in radial directions from the center of said body. 9 - Device according to claim 8, characterized in that the openings (6, -7t8,9,10) are arranged so that the overall reaction thrust resulting from the addition of the forces constituted by the jets coming from the all of the nozzles are exerted in a direction coaxial with the median axis of said chamber and in a direction opposite to the connection on the inlet pipe and liquid supply. 10 - Device according to one of claims 1 to 9, characterized in that the inner surface of the chamber within the cylindrical body forming nozzle holder es; machined until a surface finish of less than 0.05 micron is obtained. 11 - Device according to one of claims 1 to 10, characterized in that each cylindrical sleeve forming a nozzle is dimensioned so that the length of the internal bore to this sleeve represents 4 to 7 times the internal diameter of the crown defining the passage section of the liquid jet, and this tubular bore of the sleeve is greater than said passage section. 12 - Device according to one of claims 1 to 11, characterized in that the sixteen surfaces of the nozzles, placed on the cylindrical body forming the nozzle holder, is between r, and 0.11 times the internal surface of bedroom. 13 - Use of the device according to one of claims 1 to 12 er. view of a cleaning operation and it is characterized in that the speed in the supply line is between 0.6 and 0.4 times the speed of movement =: ent liquid jet within each single nozzle , for a supply pressure between 600 and SO bars.