Knibbeler, Fredericus Johannes Maria (Baden Powellstraat 10, BW 's-Hertogenbosch, NL-5215, NL)
Helma, Reinigingsdienst Vof (Einsteinstraat 8, DR Goirle, NL-5051, NL)
Pols, Lambertus Henricus Guillaume Maria (Clercxstraat 25, EA Tilburg, NL-5017, NL)
Knibbeler, Fredericus Johannes Maria (Baden Powellstraat 10, BW 's-Hertogenbosch, NL-5215, NL)
| 1. | Device for cleaning a system of pipes or a system of underground channels (2) which has at least one access opening (3), which device comprises a flexible pressure line (10), which at one end is connected to a spray head (7,8), which can be placed in the said system (2) via the access opening (3) and is provided with at least one nozzle (17,36) for delivering a jet of flushing medium (19,37), and at the other end is connected to a pressure device (11), as well as a support member (9) on which the spray head (7,8) can be moved through the system, characterized in that at least one of the nozzles (17) is directed along the pressure line (10) in order to deliver a jet of flushing medium (17) which is directed backwards along the said pressure line (10), in such a manner that in operation a tensile force is exerted on the pressure line (10). |
| 2. | Device according to Claim 1, in which the spray head (7,8) has a connection for the pressure line (10), from which connection a diverter line (18) runs towards the nozzle (17) so as to divert the flushing medium to be delivered essentially through 180°. |
| 3. | Device according to Claim 2, in which the diverter line (18) is formed in such a manner that, during operation, the liquid streams are diverted for at least two dimensions in a completely streamlined manner. |
| 4. | Device according to one of the preceding claims, in which at least a second spray head (8) is situated on the support member (9), with one or more associated nozzles (36) for delivering a jet of flushing medium (37) in such a manner that the resultant of all the jets of flushing medium (19,37) delivered by the nozzles (7,8) exerts a tensile force on the pressure line (10). |
| 5. | Device according to Claim 4, in which the jet (37) of flushing medium is directed away from the pressure line (10). |
| 6. | Device according to Claim 2,3,4 or 5, in which at least one spray head (7,8) can be adjusted with respect to the support member about a transverse pin (30,31) in order to direct the jet of flushing medium (19,37) upwards and downwards. |
| 7. | Device according to Claim 6, in which at least one spray head (7,8) can be adjusted by means of a pistoncylinder device (34,35). |
| 8. | Device according to Claim 7, in which the pistoncylinder device (34,35) is connected to the pressure line (10), and the spray head (7,8) is continuously forced towards a base position under spring preloading (32,33), in such a manner that the spray head (7,8) can be displaced counter to this preloading depending on the pressure of the flushing medium. |
| 9. | Device according to one of the preceding claims, in which an upwardly directed nozzle (20,36) is provided. |
| 10. | Device according to one of Claims 18, in which a downwardly directed nozzle (21) is provided. |
| 11. | Device according to one of Claims 18, in which a nozzle (36) which is directed sideways is provided. |
| 12. | Device according to Claim 10, in which each downwardly directed nozzle (21) opens out into a chamber (23) which in turn opens out into an aperture of larger crosssection, in order to reduce the velocity and/or pressure of the emerging jet of flushing medium. |
| 13. | Device according to one of the preceding claims, in which the support member (9) is a carriage with a flat base plate (24). |
| 14. | Device according to Claim 13, in which the base plate (24) has an edge (25) which rises obliquely upwards on the front side facing away from the pressure line (10). |
| 15. | Device according to Claim 13 or 14, in which the base plate (24) has upright side edges (27,28) as well as an upright rear edge (26). |
| 16. | Device according to one of the preceding claims, in which at least two spray heads (7,8), with their associated support members (9), are provided, the spray heads (7,8) containing at least one nozzle (17) which is directed along the pressure line (10) in order to deliver a jet of flushing medium which is directed backwards along the said pressure line (10), in such a manner that in operation a tensile force is exerted on the pressure line. |
| 17. | Device according to Claim 16, in which at least two of the spray heads (7,8) are connected to their own pressure line (10). |
| 18. | Device according to Claim 16, in which all the spray heads (7,8) are connected to a manifold (40), which manifold is connected to a pressure line (10). |
| 19. | Assembly, comprising at least two devices (6) according to one of the preceding claims, which devices (6) are placed next to one another. |
| 20. | Assembly, comprising at least two devices (6) according to Claims 118, which devices (6) are placed behind one another. |
| 21. | Assembly according to Claim 19 or 20, in which each device (6) comprises at least one spray head (7,8) which is connected to its own feed hose (10). |
| 22. | Assembly according to Claim 19 or 20, in which each device comprises at least one spray head (7,8), and at least two spray heads (7,8) are fed by means of a common feed hose (10,40). |
| 23. | Method for cleaning a system of pipes or a system of channels (2) by means of a device (5) according to one of the preceding claims, comprising a flexible pressure line (10) which at one end is connected to a spray head (7,8), which can be placed in the said system (2) via the access opening (3) and is provided with at least one nozzle (17,36) for delivering a jet of flushing medium, and which at the other end is connected to a pressure device (11), as well as a support member (9) on which the spray head (7,8) can be moved through the system (2), and at least one of the nozzles (17) is directed along the pressure line (10) in order to deliver a jet of flushing medium (19) which is directed backwards along the said pressure line (10), in such a manner that in operation a tensile force is exerted on the pressure line (10) and the support member (9) is moved forwards, under the influence of the jet of flushing medium (19) delivered by the nozzle (17), pulling the pressure line (10) along with it. |
| 24. | Method according to Claim 23, in which the pressure line (10) is accommodated on a reel (12), and the forwards movement of the support member (9) is controlled by paying out or winding in the pressure line (10). |
| 25. | Method according to Claim 24, in which the reel is positioned on a mobile frame, which frame has a maximum weight of a few times the operational weight of the reel, including the pressure line. |
| 26. | Method according to Claim 23,24 or 25, in which the flushing medium is supplied at a pressure of 50400 bar. |
| 27. | Method according to Claim 26, in which the flushing medium is supplied at a pressure of 125225 bar. |
A device of this kind is known from GB-A-1,460,031. The spray head of this device is mounted on a type of carriage, which has to be pulled through the pipe to be cleaned by means of cables. The spray head is directed forwards and has to be held by means of the cables, since otherwise it would push the carriage, together with the pressure line, backwards as a result of the reaction force generated by the emerging jet of liquid.
The device can be used while the system of pipes or system of channels is in operation. In particular, the pipes or channels involved relate to systems which convey a mixture of water and substances which are released during oil refining, such as crude oil, lubricant, paraffin products and the like.
Sand and other fine particles usually settle out of mixtures of this kind.
Furthermore, it is also possible that certain liquids, such as heavy oils and fats, will congeal or coagulate. These various phenomena result in sedimentation or caking.
When the systems of pipes or channels are being cleaned, the highest part of the systems is treated first. The dislodged sediment or cake fragments then flow towards those parts which are situated at a lower level and are treated subsequently, so that the entire system can be completely cleaned. The dislodged sediment and/or cake fragments are generally sucked out downstream at a distance from the location where they are dislodged which is such that there is scarcely any resettling of this sediment.
Such a mixture of contaminated"black"liquid generally also contains volatile substances which are flammable and/or explosive. If cleaning work involves such a discharge system being drained, the problem arises that the volatile substances are released from the drained contaminated sediment. Even if the system is then
degassed, the risk of explosions remains high.
In GB-A-1,460,031, it is proposed to generate turbulence, by means of a spray head, in the liquid situated in the system, in such a manner that the sediment passes into a suspension and can then be removed by pumping.
However, a drawback of the known device is that the system is not easy to manipulate and move onwards. It is firstly necessary to tension cables which bridge the distance between two successive manholes. To position these cables, it is necessary, for example, to use a separate robot; as an alternative, the cables can be positioned manually. Such a procedure is laborious and not devoid of risk.
Particularly when the lines are full and/or there is a risk of explosion, it is necessary to use a robot which, however, can easily become stuck.
The object of the invention is therefore primarily to provide a device for cleaning a system of pipes or a system of underground channels which does not have this drawback. This object is achieved by the fact that at least one of the nozzles is directed along the pressure line in order to deliver a jet of flushing medium which is directed backwards along the said pressure line, in such a manner that in operation a tensile force is exerted on the pressure line.
In the device according to the invention, the support member is pushed forwards in the pipe or channel as a result of the reaction force of the jet of flushing medium which is directed backwards and is delivered at high pressure, and the pressure line is dragged along behind the support member. Meanwhile, the delivered jet or jets of the flushing medium exert a highly erosive action on the sediment.
Moreover, the suspended sediment is driven backwards, in such a manner that it can be sucked out at a suitable location, preferably in the region of the access opening via which the cleaning device is introduced.
As the spray head is moved forwards, with its movement being controlled by paying out the pressure line more or less quickly under the influence of the tensile force exerted by the flushing medium, the pipe or the channel is gradually treated further and further on. After a certain distance has been covered, the support member can be brought back by hauling in the pressure line. If desired, the cleaning process can be repeated from the beginning until the desired level of cleaning has been achieved.
The spray head may be designed in all kinds of ways. It has a connection for
the pressure line, from which connection a diverter line can run towards the nozzle, so as to divert the flushing medium to be delivered essentially through 180°.
Depending on the spray pressures to be delivered and the size of the pipes or channels to be treated, a plurality of nozzles which are directed backwards can be used.
Furthermore, at least a second spray head may be situated on the support member, with one or more associated nozzles for delivering a jet of flushing medium, in such a manner that the resultant of all the jets of flushing medium delivered by the nozzles exerts a tensile force on the pressure line. If the spray head is situated on the front part of the support member, it is preferred for the jet of flushing medium delivered to be directed away from the pressure line. If a forwardly directed spray head of this kind is used, the sediment can be subjected to a preliminary treatment, in such a manner that the sediment can be removed more quickly and more thoroughly when the backwardly directed spray head passes by.
Preferably, at least one spray head can be adjusted with respect to the support member about a transverse pin, in order to direct the jet of flushing medium upwards and downwards. By directing the jet in a suitable manner, it is possible to remove even any residual hard caking residues.
At least one spray head can adjusted by means of a piston-cylinder device; the piston-cylinder device is connected to the pressure line, while the spray head is continuously forced towards a base position under spring preloading, in such a manner that the spray head can be displaced counter to this preloading depending on the pressure of the flushing medium.
Furthermore, an upwardly directed nozzle and a downwardly directed nozzle may be provided in order to clean the entire cross-section of a pipe or channel.
Each downwardly directed nozzle can open out into a chamber which in turn opens out into an aperture of larger cross-section, in order to reduce the velocity and/or pressure of the emerging jet of flushing medium. These upwardly and downwardly directed jets, as well as optional jets which are directed sideways, can be used to blast free a caked-on layer, which may also be covered with loose sediment.
By means of the downwardly directed jets, the top layer of sediment can be brought into a liquid-like state, in such a manner that this layer can flow away as a liquid under the force of gravity.
This flow can be assisted further by means of one or more of the backwardly directed jets, which are preferably directed in such a manner that they do not erode the sediment situated behind, but rather accelerate the liquid-like sediment mixture towards the suction point.
Preferably, the support member is designed as a carriage with a flat base plate.
The base plate may have an edge which rises obliquely upwards on the front side facing away from the pressure line. Furthermore, the base plate may have upright side edges as well as an upright rear edge. The support member can rest on the sediment without sinking into the sediment sufficiently deeply to impair the effectiveness of the nozzles.
The spray head described above may have one or more nozzles. It is suitable for treating pipes or channels with specific cross-sectional dimensions which may not exceed a maximum which is determined by the force of the jets delivered and their position, so as not to impair the effectiveness of the device. To treat pipes or channels of relatively large cross-sectional dimensions, two or more spray heads may be provided, each with at least one nozzle which is directed along the pressure line, in order to deliver a jet of flushing medium which is directed backwards along the said pressure line, in such a manner that in operation a tensile force is exerted on the pressure line.
According to a first variant, at least two of the spray heads, with their associated support member, are connected to their own pressure line; as an alternative, all the spray heads may be connected to a manifold, which manifold is connected to a pressure line. The manifold may be formed in accordance with (a part of) the cross-section of the pipe or channel.
The invention furthermore relates to a method for cleaning a system of pipes or a system of channels by means of a device as described above, comprising a flexible pressure line which at one end is connected to a spray head, which can be placed in the said system via the access opening and is provided with at least one nozzle for delivering a jet of flushing medium, and which at the other end is connected to a pressure device, as well as a support member on which the spray head can be moved through the system, and at least one of the nozzles is directed along the pressure line in order to deliver a jet of flushing medium which is directed backwards along the said pressure line, in such a manner that in operation a tensile
force is exerted on the pressure line and the support member is moved forwards, under the influence of the jet of flushing medium delivered by the nozzle, pulling the pressure line along with it.
The pressure line may be accommodated on a reel in such a manner that the forwards movement of the support member is controlled by paying out or winding in the pressure line.
The reel is often attached to a mobile pressure device, but it is also possible for the reel to be situated on a mobile frame, in which case the frame has a weight which is a number of times less than that of the pressure device. A reel of this kind, which is mounted on a mobile frame of low weight, makes it possible to reach locations to which it is difficult to gain access, for example where the access opening to the system of pipes or channels is situated within an area with weak or poor ground conditions, or in areas with a small positioning surface which is only suitable for a mobile frame of this kind.
The flushing medium can be supplied at a pressure of 50-400 bar; preferably, the flushing medium is supplied at a pressure of 125-225 bar.
The invention will be explained in more detail below with reference to the embodiments which are illustrated in the figures, in which: Figure 1 shows a cross-section through a piece of ground with a pipe in which the cleaning device according to the invention has been placed.
Figure 2 shows a side view, partially in section, of a support member with spray heads.
Figure 3 shows a horizontal section through a spray head in accordance with Figure 2.
Figure 4 shows a partially cut-away section through a downwardly directed nozzle.
Figure 5 shows a bottom view of the support member.
Figure 6 shows a cross-section through an alternative nozzle.
Figure 7 shows a dual design of the cleaning device according to the invention.
Figure 8 shows an embodiment with four support members and spray heads.
The overview which is illustrated in Figure 1 shows a piece of ground 1 in which the pipe, which is denoted by 2, is arranged. The pipe is accessible via
manhole 3. A layer of sediment 4, consisting of sand and other fine particles, has formed in the pipe 2. The pipe is further filled with, for example, oil-containing water (5) (black water), comprising a mixture of water, fats, paraffin and other substances which are released during oil refining. In this example, the pipe is 100% full.
This sediment 4 has to be churned free and discharged when the pipe 2 is being cleaned. The cleaning device which is denoted overall by 45 is used to carry out this operation, the device comprising a unit 6 with attached spray heads 7,8, as well as a support member 9.
The spray heads are fed via a pressure line 10, which is connected to a lorry 11 on which are situated a pump and a water reservoir.
The pressure line 10 is preferably unwound from a reel 12 and is diverted to the unit 6 via a support 13.
A suction line 14 is also lowered into the manhole 3, which suction line is connected to a lorry 15 on which is situated a suction pump with a container for holding the sediment which is churned free.
The unit 6 is illustrated on a larger scale in Figure 2. It comprises a carriage- like support member 9, a rear spray head 7 and a front spray head 8. At the top, the unit is covered by a grid of bars 16 which protect the spray heads 7,8.
The backwardly directed spray head has a plurality of backwardly directed nozzles 17, as can also be seen in the horizontal section shown in Figure 3. The liquid, which is supplied at high pressure via pressure line 10, is diverted in the interior chamber 18 in the spray head 7 and is directed backwards, with the result that the emerging jets are obtained. These emerging jets of liquid 19 firstly push the unit 6 forwards, dragging the pressure line 10 along behind it. In addition, the jets of liquid 19 loosen the sediment, so that it becomes suspended in the liquid 5 and ultimately can be sucked out via the suction line 14.
With regard to chamber 18, it is preferred for the shape to be such that, during operation, the streams of liquid are diverted, at least with regard to two dimensions, in a completely streamlined manner.
One or more nozzles 20 which are directed further upwards are also arranged on the spray head 7, which nozzles deliver an upwardly directed jet of liquid in order to loosen parts of the sediment which are situated at a higher level.
A downwardly directed nozzle 21 is also provided in the carriage 9 of the unit 6. This nozzle 21, which is shown in section on a larger scale in Figure 4, is fed via line 22, which is connected to the pressure line 10.
The liquid emerging from the line 22 at high pressure passes into a widened chamber 23, in such a manner that the liquid emerges at the underside of the carriage 9 at a lower velocity, and can then additionally bring the sediment into suspension.
The carriage 9 has a flat bottom 24, as is also shown in the bottom view in accordance with Figure 5, as well as a front side 25 and rear side 26 which run obliquely upwards. Upright walls 27,28 are also provided. The advantage of a carriage 9 designed in this way is that the unit 6 will not sink quickly into the sediment. The forward movement of the unit 6 under the influence of the jets of liquid 19 delivered through the nozzles 17 causes the unit 6 to slide over the sediment without sinking too deeply into the latter.
As shown in Figure 2, both the spray head 7 and the spray head 8 can be arranged such that they can rotate about transverse pins 30,31. By means of the springs 32,33, both spray heads 7,8 are directed in such a way that their jets are directed only slightly upwards. The hydraulic piston-cylinder devices 34,35 act counter to the action of the springs 32,33. These piston-cylinder devices can be actuated, for example, by the liquid supplied via the pressure line 10. At a specific pressure of this liquid, the piston-cylinder devices 34 and 35 extend counter to the action of the springs 32 and 33, respectively. By changing the pressure of the liquid supplied via the pressure line 10, it is thus possible to change the direction of the jets of liquid delivered by the spray heads 7,8. It is thus possible for both higher and lower parts of the sediment to be reached directly by these jets.
The spray head 8 also has nozzles 36, which can be directed forwards, upwards and to the side, in order to deliver jets of liquid 37.
In the variant illustrated in Figure 6 of a nozzle which opens out on the underside of the base plate 24 of the carriage 9, the liquid line 38 is provided with a nozzle 39 which opens out into the housing 29 in an approximately tangential direction. As a result, a turbulent, downwardly directed stream is generated in chamber 23 of housing 29, which turbulent stream emerges outwards from the base plate 24 of the carriage 9. A turbulent jet of this kind can also be used to bring the sediment into suspension.
In the case of pipes which have a relatively large diameter, two units 6, each with their own pressure line 10, can be moved through the line next to one another.
As an alternative, it would also be possible for four units 6 of this kind to be connected to pressure line 10 via manifold 40 and to be moved jointly through the pipe in question.
The unit 6 is moved through the pipe 2 by unwinding pressure line 10 from reel 12 or winding it onto reel 12 in a controlled manner. The unit 6 can be moved backwards and forwards through the line 2 until the desired level of cleaning has been achieved.
Even if the unit 6 is situated at a relatively great distance from the manhole 3, the suspended sediment particles can still be sucked at that location. This is because the suspended sediment is conveyed towards the said manhole 3 under the influence of the backwardly directed jets of liquid 17 which are delivered by the spray head 7.