NO20180168A1 - Cleaning apparatus for cleaning a submerged portion of a structure and method for use of said cleaning apparatus - Google Patents

Description

CLEANING APPARATUS FOR CLEANING A SUBMERGED PORTION OF A STRUCTURE AND METHOD FOR USE OF SAID CLEANING APPARATUS

This invention relates to a cleaning apparatus for removing organisms that are attached to a structure which is fully or semi-submerged in water. The structure may be a pipe-shaped floatation body in a fish pen. More particularly, this invention relates to a cleaning apparatus having cleaning means with adjustable orientation for creating a cleaning surface that have a similar shape as a surface on the structure to be cleaned, for example a pipe. Being able to adjust the orientation of the cleaning means, such that the shape of the cleaning apparatus may mimic the shape of the structure, means that a larger portion of the structure can be cleaned with each passing of the cleaning apparatus. This invention also relates to a cleaning apparatus that may pass obstacles on the structure to be cleaned without having to remove the obstacle or remove the cleaning apparatus from the structure. An obstacle may for example be a bracket connecting two pipe-shaped floatation bodies. The position of the cleaning means may be adjusted to allow the cleaning apparatus to pass the obstacle without contact between the cleaning means and the obstacle.

Structures that are fully or semi-submerged in water will over time become overgrown with various marine organisms. Such overgrowing, or fouling, involve shell, barnacle, seaweed and kelp. The fouling increases the weight of the structure to submerge it deeper than intended.

An example of a semi-submerged structure is a floatation body in a fish pen. The floatation body may have several shapes, but a common shape is a closed circular pipe. The floatation body may comprise two concentric pipes. The pipes are held together by radially oriented brackets evenly distributed along the floatation body. A walkway may be arranged on an upper side of the floatation body for personnel to move around the fish pen. The fish pen may further comprise a net connected directly or indirectly to the inner of the two pipes to form an enclosure for fish.

In certain jurisdictions, there are rules demanding that equipment being relocated between locations for fish farming must be cleaned and disinfected before relocation. The risk of transfer of infections from location to location will thereby be reduced.

Over time, the fish pens for fish farming have become larger and larger. The floatation body can for example be 120m long, and even longer. Thus, it is extensive work to clean the floatation body. It is an advantage to clean the floatation body regularly as this will reduce the weight of the fouling.

However, this requires that cleaning is performed with the net and moorings in place. With the known prior art is has proven difficult to clean the floatation body with the net connected to the pen.

Patent document WO 2011/087371 discloses a cleaning apparatus for a floatation ring in a fish pen. The net in the fish pen is removed in advance. The mooring of the floatation ring is released. The cleaning apparatus is installed hanging on the stern of a vessel, e.g. a ship or boat. A portion of the floatation ring is lifted above the water surface with a crane and placed on rollers in the cleaning apparatus. The floatation ring is long, and all material aspects of the floatation ring will float in the water surface. Some of the rollers is powered by a motor, and the floatation ring is displaced through the cleaning apparatus by the rollers rotating. As the floatation ring is released from the mooring, the floatation ring will slowly revolve while the vessel is still. A portion of the floatation ring that are raised above the water surface is cleaned by pressurized water from rotating nozzles. Fouling that are cleaned off the underside of the floatation ring are washed to sea.

Patent document NO 20101673 discloses an apparatus for cleaning of ship hulls. The apparatus comprises three cleaning devices. Each cleaning device being provided with a cleaning disc having a plurality of nozzles for ejecting a liquid under pressure against the surface to be cleaned. Each cleaning device is hinged to a central unit for minor adjustments of the orientation of the cleaning device.

Thus, there is a need for a cleaning apparatus for removing fouling on a floatation ring or a floatation collar in a fish pen while the net and mooring is connected to the float-ring. Such a cleaning apparatus would render possible cleaning of the float-ring while the fish pen contains fish and several cleanings during the harvest cycle. The cleaning apparatus should be capable of passing obstacles without disconnecting from the structure being cleaned. There is also a need for a cleaning apparatus that is not dependent on personnel moving on the walkway of the fish pen, as this constitute a safety hazard. Thus, it is advantageous having a remotely operated cleaning apparatus. It is also a need for a cleaning apparatus that can be configured to collect the main fouling removed from the float-ring or float-collar.

The invention has for its object to remedy or to reduce at least one of the drawbacks of the prior art, or at least provide a useful alternative to prior art.

The object is achieved through features, which are specified in the description below and in the claims that follow.

The invention is defined by the independent patent claims. The dependent claims define advantageous embodiments of the invention.

In a first aspect, the invention relates to a cleaning apparatus for cleaning a submerged portion of a structure, the cleaning apparatus comprising:

- a frame comprising a first side portion, a second side portion and a longitudinal axis;

- a plurality of cleaning means connected to both the first side portion and the second side portion of the frame, wherein each cleaning means has a centre and an adjustable orientation relative to the frame,

wherein at least one coupling unit is connected to at least two cleaning means on the same side portion.

The invention solves the above-mentioned challenges by providing a cleaning apparatus comprising cleaning means with adjustable orientation to follow the shape of the structure to be cleaned. Thus, the cleaning apparatus may clean for example a flat structure, a curved structure and in particular a circular structure. The cleaning means may be arranged such that a cleaning footprint of one cleaning means overlaps with the cleaning footprint of an adjacent cleaning means. The cleaning means may be connected to the frame by hinges for adjusting the orientation of the cleaning means.

The cleaning apparatus further comprises at least one coupling unit connected to at least two cleaning means and wherein a displacement of the coupling unit may result in an adjusted orientation of at least one of the cleaning means connected to the coupling unit. The displacement of the coupling unit may be a result of an external component of force acting on the coupling unit, for example if the coupling unit, in operational use, comes into contact with an obstacle. There may be obstacles on the structure to be cleaned that normally would require the cleaning apparatus to be removed from the structure to pass the obstacle, before continuing the cleaning. The coupling unit may render it possible for the cleaning apparatus to pass these obstacles without being removed from the structure. In operational use, the coupling unit may slide along the obstacle such that it is displaced. The displacement would result in one or both the cleaning means connected to the coupling unit also displacing, i.e. adjusting their orientation. Thus, the cleaning means may go clear of the obstacle and pass it without restricting a movement of the cleaning apparatus.

The coupling unit may for example be a rod, a cylinder or a damper. A first end portion and a second end portion of the coupling unit may be connected to the cleaning means by a rotatable joint, for example a ball joint. The rotatable joint may enable adjusting the orientation of one of the cleaning means connected to the coupling unit, without affecting the orientation of the other cleaning means connected to the coupling unit. The coupling unit may be extendable. This may further enable adjusting the orientation of one cleaning means without affecting the orientation of the other cleaning means.

In one embodiment, the cleaning means may be arranged in pairs, one on either side portion of the frame. The cleaning means in each pair may have an equal distance from their centre to the longitudinal axis of the frame, when arranged in the same orientation relative to the frame.

Two cleaning means, one on either side portion of the frame, may, in operational use, extend above a centre line of the structure, e.g. a pipe, being cleaned. Said cleaning means may extend out of the water in which the structure is submerged. Extending out of the water may cause the cleaning means to drag air around the submerged portion of the structure, which may improve the cleaning.

In one embodiment, a distance from the centre of at least two cleaning means to the longitudinal axis are different when arranged in the same orientation relative to the frame. In one embodiment, all the cleaning means may have a different distance from their centre to the longitudinal axis when arranged in the same orientation relative to the frame. In one embodiment, all the cleaning means connected to the same side portion of the frame may have a different distance from their centre to the longitudinal axis when arranged in the same orientation relative to the frame. In one embodiment, the cleaning means may be arranged in pairs, one cleaning means on either side portion of the frame, wherein both cleaning means in a pair have the same distance from their centre to the longitudinal axis when arranged in the same orientation relative to the frame, and wherein the cleaning means in the different pairs have different said distance when arranged in the same orientation relative to the frame.

In one embodiment, the cleaning apparatus may comprise a centre cleaning means arranged with the centre substantially in line with the longitudinal axis of the frame. The centre cleaning means may be connected to a front portion of the frame. The centre cleaning means may be connected in a fixed orientation. The centre cleaning means may create a continuous cleaning surface between the cleaning means arranged on the first side and the second side of the frame.

In one embodiment, the cleaning apparatus may further comprise a rotatable cleaning disc connected to each cleaning means, the cleaning disc comprising a rotational axis, a cleaning side, a back side opposite the cleaning side, a peripheral portion and at least one nozzle for emitting a fluid jet under pressure, the nozzle being in liquid communication with a liquid reservoir. The cleaning disc may have a rotational axis parallel to the centre axis of the cleaning means. In one embodiment, the rotational axis may coincide with the centre axis. The nozzle may be arranged on the cleaning disc with a distance from the centre axis. The fluid jet may, in use, cause the cleaning disc to rotate about the rotational axis.

The fluid jet may be a liquid, such as water. In one embodiment, the fluid jet may be a mixture of different liquids, such as water and chemicals. The chemicals may have biocidal properties for reducing biological growth after cleaning. In one embodiment, the liquid may be heated, for example to 60 degrees Celsius or 70 degrees Celsius. A hot liquid may have biocidal properties for reducing and/or delaying biological growth after cleaning.

In one embodiment, the cleaning disc may comprise a plurality of nozzles, and wherein the fluid jet emitted from each nozzle, in use, form an angle relative to a radial direction of the cleaning disc, said angle being different for each fluid jet. Fluid jets with different angles may increase the area being cleaned by each cleaning disc. In one embodiment, the cleaning disc may comprise two nozzles, three nozzles, four nozzles or more than four nozzles.

In one embodiment, said nozzles may be arranged in the peripheral portion. In one embodiment, the at least one nozzle is arranged at the peripheral portion. In one embodiment, the plurality of nozzles is arranged at the peripheral portion. The peripheral portion may be the portion of the cleaning disc furthest away from the centre axis. The further away from the centre axis the nozzle is arranged, the larger the moment arm from the fluid jet becomes, and the less force is required to rotate the cleaning disc. Arranging the nozzle at the peripheral portion may give maximum moment arm.

In one embodiment, the rotatable cleaning disc may further comprise at least one recess in the peripheral portion, the recess having a bore arranged angularly relative to the rotational axis and the radial direction of the cleaning disc, wherein the recess provides a channel for a surrounding liquid to flow from the cleaning side to the back side of the cleaning disc. When the cleaning disc is rotated, the recess may create a suction from the cleaning side to the back side if the cleaning disc. The suction may cause surrounding liquid and debris to be transported through the recess. The surrounding liquid may also partly consist of the liquid emitted from the nozzle. In one embodiment, the cleaning disc may comprise more than one recess. In one embodiment, the bore may be arranged angularly relative to the centre axis and angularly relative to a radial direction of the cleaning disc.

The cleaning apparatus may comprise a return system connected to the cleaning means for collecting debris and the surrounding liquid. Debris may be various marine organisms such as shell, barnacle, seaweed and kelp. In use, the liquid emitted from the nozzle may cut off debris growing on the structure being cleaned. The return system may collect the debris after it is sucked through the recess on the cleaning disc. The return system may transport the debris to a reservoir for further processing or disposal.

In one embodiment, the cleaning apparatus may comprise sensor equipment for detecting obstacles in the water. Sensor equipment may comprise different sensor components for use in water as known from the prior art, for example a sonar. The sensor equipment may be used to detect obstacles in the water if the visibility is poor.

The cleaning apparatus may comprise an attachment for connection to a remotely operated vehicle.

In one embodiment, a cleaning vehicle comprises the cleaning apparatus and a remotely operated vehicle, wherein the remotely operated vehicle is configured for relocating the cleaning apparatus in water.

In a second aspect, the invention relates to use of the cleaning apparatus for cleaning a submerged portion of a structure.

In one embodiment, the cleaning vehicle is used for relocating the cleaning apparatus in water.

It is also described a cleaning apparatus for cleaning a submerged portion of a structure, the cleaning apparatus comprising:

- a frame comprising a first side portion, a second side portion and a longitudinal axis;

- a plurality of cleaning means arranged on both the first side portion and the second side portion of the frame, wherein each cleaning means has a centre;

- at least one rotatable cleaning disc connected to the cleaning means, said disc having a rotational axis, a cleaning side and a opposite back side, a centre and a peripheral portion; and

- a plurality of nozzles arranged in the peripheral portion of the cleaning disc for emitting a fluid jet, wherein an angle of the fluid jet relative to a radial direction of the cleaning disc are different for each nozzle.

Such a cleaning apparatus has the advantage that the cleaning disc may clean a larger surface area due to the fluid jets being emitted in different angles. In one embodiment, the fluid jet may also be angular relative to the cleaning side of the cleaning disc.

It is also described a cleaning apparatus for cleaning a submerged portion of a structure, the cleaning apparatus comprising:

- a frame comprising a first side portion, a second side portion and a longitudinal axis;

- a plurality of cleaning means arranged on both the first side portion and the second side portion of the frame, wherein each cleaning means has a centre;

- at least one rotatable cleaning disc connected to the cleaning means, said disc having a rotational axis, a cleaning side and a opposite back side, a centre and a peripheral portion; and

- at least one recess arranged in the peripheral portion of the cleaning disc, wherein the recess has a bore arranged angularly relative to a radial direction of the cleaning disc and the rotational axis, wherein the recess provides a channel for a surrounding liquid to flow from the cleaning side to the back side of the cleaning disc.

In the following is described an example of a preferred embodiment illustrated in the accompanying drawings, wherein:

Fig.1 shows a perspective view of a cleaning apparatus according the invention;

Fig.2 shows, in the same scale as figure 1, a top view of the cleaning apparatus in a flat configuration;

Fig.3 shows, in a larger scale than figure 1, a top view of a cleaning disc;

Fig.4 shows, in the same scale as figure 3, a side view of the cleaning disc arranged in a cross section of a housing;

Fig.5 shows, in the smaller scale than figure 1, a side view of the cleaning apparatus in the flat configuration;

Fig.6 shows, in the same scale as figure 1, an end view of the cleaning apparatus positioned around a pipe;

Fig.7 shows, in the same scale as figure 1, a perspective view of a cleaning vehicle comprising the cleaning apparatus connected to a remotely operated vehicle;

Fig.8 shows, in a smaller scale than figure 1, an end view of the cleaning vehicle positioned around a floatation collar in a fish pen;

Fig.9a shows, in a larger scale than figure 1, a detail of the cleaning apparatus as it passes a bracket on the floatation collar;

Fig.9b shows, in the same scale as figure 9a, the same detail as in figure 9a from a different angle, and

Fig.10 shows, in the same scale as figure 7, a sideview of the cleaning vehicle.

The figures are depicted in a simplified manner, and details that are not relevant to illustrate what is new with the invention may have been excluded from the figures. The different elements in the figures may necessarily not be shown in the correct scale in relation to each other. Equal reference numbers refer to equal or similar elements.

In what follows, the reference numeral 1 indicates a cleaning apparatus according to one embodiment of the invention. Figure 1 and 2 show the cleaning apparatus 1 comprising a frame 2 with a surface 200. The frame 2 comprises a first side portion 202 and a second side portion 203, and a longitudinal axis 10 between the first side portion 202 and the second side portion 203. The cleaning apparatus 1 further comprise several cleaning means 3, 3a. In this particular embodiment, the cleaning apparatus 1 is shown with seven cleaning means 3, 3a. A centre cleaning means 3a is fixed to a front portion 20 of the frame 2. The remaining cleaning means 3 are arranged in pairs. Each cleaning means 3 in a pair is shown to have the same distance from a centre 300 of the cleaning means 3 to the longitudinal axis 10, the cleaning means 3 being arranged in the same orientation. The distance from the centre 300 of the cleaning means 3 to the longitudinal axis 10 are different for each pair, the cleaning means 3 being arranged in the same orientation.

The centre 300 of the cleaning means 3 arranged closest to the front portion 20 is closer to the longitudinal axis 10 than the centre 300 of the adjacent pair of cleaning means 3. The centre 300 of the cleaning means 3 arranged furthest away from the front portion 20 is further away from the longitudinal axis 10 than the centre 300 of the adjacent pair of cleaning means 3. It should be noted that the above is only one way of arranging the cleaning means 3 relative to the longitudinal axis 10, and that the position of the cleaning means 3 may be different for other embodiments.

The paired cleaning means 3 are shown to be connected to the frame 2 by hinges 30a, 30b, 30c for adjusting the orientation and position of the cleaning means 3. Thus, the cleaning apparatus 1 may form a shape according to the surface 101 on the structure 100 to be cleaned (see figure 6). The hinges 30a, 30b, 30c comprise a rubber pad 31. The rubber pad 31 forms a flexible joint. A stiffness of the rubber pad 31 may result in a force trying to rotate the cleaning means 3 towards the surface 101 to be cleaned.

The cleaning means 3, 3a comprises a housing 5. A cleaning disc 32 is arranged within the housing 5. Each cleaning means 3, 3a comprises a guiding element 40 connected to the housing 5. The guiding element 40 forms a curved surface for guiding the cleaning means 3, 3a over small obstacles and unevenness’s on or along the surface 101 (see figure 6) to be cleaned.

Now looking at figures 3 and 4, the cleaning disc 32 comprise a cleaning side 33 and an opposite back side 37. A centre 320 of the cleaning disc 32 is provided with a hollow axle 34 supported by a swivel (not shown) in the housing 5. The axle 34 forms an axis 301 also acting as the rotational axis 301 of the cleaning disc 32. The cleaning disc 32 further comprises at least one nozzle 35. The cleaning disc 32 is shown to comprise four nozzles 35 arranged at a peripheral portion 310 of the cleaning disc 32. In another embodiment, the number of nozzles 35 may be one, two, three or more than four. Supplying a pressurized liquid to each nozzle 35 may result in a fluid jet 4 being expelled from each nozzle 35. The fluid jets 4 may cause the cleaning disc 32 to rotate about the rotational axis 301. The fluid jet 4 forms an angle (α1 and α2 in figure 3) relative to a radial direction of the cleaning disc 32. The fluid jet 4 also form an angle (φ in figure 4) relative to the rotational axis 301. In this particular embodiment, the angle α1, α2 are shown to be different for each fluid jet 4. For each cleaning means 3 in a pair, the cleaning disc 32 may rotate in an opposite direction relative to each other as a result of a direction of the fluid jets 4.

The cleaning disc 32 further comprises at least one recess 36 in the peripheral portion 310. The recess 36 extends through the cleaning disc 32, from the cleaning side 33 to the back side 37. The recess 36 forms a bore 360 arranged angularly relative to the rotational axis 301 and relative to the radial direction of the cleaning disc 32, as shown by line 302 in figure 3. In the figures, each cleaning disc 32 is shown to have four recesses 36. When the cleaning disc 32 rotates, a surrounding liquid and particles, in the following called effluent, flows from the cleaning side 33 to the back side 37 of the cleaning disc 32, through the recess 36. The effluent may flow to a return system (not shown) and further to a return reservoir (not shown), as explained in more detail later.

Figure 5 shows the cleaning apparatus 1 in a flat configuration. The angle φ of the fluid jets 4 relative to the rotational axis 301 is such that they will form an angle relative to the surface 101 to be cleaned (see also figure 6). In the figures, this angle is shown to be small. In one embodiment, the angle of the fluid jet 4 relative to the surface 101 to be cleaned may be less than 30 degrees. The fluid jet 4 acts cuttingly against the attachment of fouling or debris to the surface 101 to be cleaned. A pressure of the fluid jet 4 may be high, for example 200 bar. The fluid jet 4 forms a counterforce on the cleaning means 3, 3a. The counterforce acts to push the cleaning means 3 away from the surface 101. However, a force, in the following called suction force, acting opposite the counterforce, is formed from the flow of the effluent liquid through the recess 36. The suction force may be greater than the counterforce from the fluid jets 4, keeping the cleaning means 3 in position against the surface 101. The guiding elements 40 are provided with an elevation 400 for maintaining a minimum distance between the cleaning means 3, 3a and the surface 101. If the cleaning means 3, 3a are sucked closer to the surface 101 than the minimum distance it may restrict movement of the cleaning apparatus 1 along the structure 100.

To obtain said suction force, the cleaning disc 3 must be positioned at a certain maximum distance away from the surface 101, in operational use. Figure 6 shows the cleaning apparatus 1 in an operable position against a pipe 100. The orientation of the cleaning means 3 is adapted to the curvature of the surface 101, in the figures shown as a circular surface 101. The cleaning means 3 may be provided with buoyancy means (not shown). The buoyancy means form an upwards-acting force on the cleaning means 3 when in water, creating a rotation of the cleaning means 3 about the hinge 30a, 30b, 30c. In another embodiment, the hinge 30a, 30b, 30c may be spring-loaded (not shown) for rotating the cleaning means 3, or the cleaning means 3 may be connected to a motor (not shown) for rotating the cleaning means 3. In one embodiment, the cleaning apparatus 1 may comprise sensor equipment (not shown). The sensor equipment may detect obstacles, such as brackets 81, in the water. The sensor equipment may comprise a sonar. In one embodiment, the sensor equipment may communicate with a control device (not shown) controlling the means for adjusting the orientation of the cleaning means 3. In use, the sensor equipment may detect an obstacle on the surface being cleaned. The sensor equipment sends a signal to the control device. The control device may then send a demand to adjust the orientation of the cleaning means 3 such that it may pass the obstacle 81.

The cleaning apparatus 1 further comprises a coupling unit 7 for connecting adjacent cleaning means 3 (see figure 2). The coupling unit 7 is shown as an extendable cylinder in the figures. A first end portion 70 of the coupling unit 7 is connected to the housing 5 of a first cleaning means 3 by means of a first rotatable connection 72a, in the figures shown as a ball joint 72a. A second end portion 71 of the coupling unit 7 is connected to the housing 5 of a second cleaning means 3 adjacent the first cleaning means 3 by means of a second rotatable connection 72b, in the figures shown as a ball joint 72b. The rotatable connection 72a, 72b enables the cleaning means 3 to be orientated independently, without being restrained by the coupling unit 7. The primary function of the coupling unit 7 is to guide, in operational use, the cleaning apparatus 1 past obstacles along the structure 100. Figure 8 shows the cleaning apparatus 1 operable on a floating pipe 102 of a fish pen 8. The floating pipe 102 is one of two concentric pipes 102, 103 connected by a plurality of brackets 81. The brackets 81 are distributed evenly along the pipes 102, 103. In operational use, the cleaning apparatus 1 is guided along the pipe 102 with the front portion 20 as a leading portion. The cleaning apparatus 1 may be guided manually, for example by a diver, or by a vehicle, for example a remotely operated vehicle. As the cleaning apparatus 1 reaches a bracket 81 the coupling unit 7 may come into contact with the bracket 81. The forward movement of the cleaning apparatus 1 may result in the coupling unit 7 sliding along the bracket 81 and pushing the cleaning means 3 connected to the first end 70 of the coupling unit 7 away from the pipe 102 so it can pass below the bracket 81. When the cleaning means 3 has passed the bracket 81, the cleaning means 3 will regain its initial position prior to passing the bracket 81.

Figure 7 shows a cleaning vehicle 19 according to one embodiment of the invention. The cleaning vehicle 19 comprises the cleaning apparatus 1 as described above connected to a remotely operated vehicle (ROV) 9. The ROV 9 may be manoeuvred to guide the cleaning apparatus 1 along the surface 101 to be cleaned. The cleaning vehicle 19 may be operated from a support vessel (not shown). The ROV 9 may be supplied with energy from the support vessel via an umbilical 96. Pressurized liquid may also be supplied from the support vessel to the nozzles 35. The cleaning vehicle 19 may be launched from the support vessel.

The ROV 9 comprises thrusters 91, 92, 93 for propulsion, manoeuvring and positioning. The thrusters 91, 92, 93 are arranged in a body 90 to reduce the risk of damage to the thrusters 91, 92, 93 and other objects such as a net in the fish pen. The ROV 9 is shown with four substantially vertical thrusters 91, two thrusters 91 on either side 900, 901 (see figure 8) of the ROV 9. The substantially vertical thrusters 91 may provide upwards and downwards propulsion. The ROV 9 is further shown with eight thrusters 93 for forwards and backwards propulsion (see also figure 10), four thrusters 93 arranged in a front portion 903 and four thrusters 93 arranged in an aft portion 904. The ROV is also shown with four thrusters 92 for sideways propulsion, two thrusters 92 in the front portion 903 and two thrusters 92 in the aft portion 904.

In the embodiment, the ROV 9 may comprise a camera (not shown) and light (not shown) arranged within a protective casing 95. A view from the camera may be transferred via the umbilical 96 to a control station (not shown) to operate the ROV 9 and/or cleaning apparatus 1. In water, the cleaning apparatus 1 may have a slight negative buoyancy, such as 5 kg. The ROV 9 may be provided with buoyancy elements (not shown) to achieve neutral buoyancy of the cleaning vehicle 19.

Figure 9a and 9b shows a detailed view of the cleaning apparatus 1, wherein the coupling unit 7 is in contact with the bracket 81 on the fish pen. The coupling unit 7 is shown to have abutted the bracket 81 and thus displaced the cleaning means 3 connected to the first end portion 70 of the coupling unit 7 away from the pipe 102. When the cleaning means 3 passes the bracket 81, it will move back into position against the pipe 102 by action of a combination of the suction force, buoyancy elements in the cleaning means 3 and the rubber pad 31. The cleaning apparatus 1 may also pass other obstacles.

Figure 10 shows a sideview of the cleaning vehicle 19. Effluent flowing, in operational use, through the recesses 36 on the cleaning discs 32 as described above may be transported from the cleaning means 3 to a return reservoir (not shown) via the return system (not shown) within the ROV 9. A flexible hose 61 connects each paired cleaning means 3 to the return system, forming a fluid communication between the cleaning means 3 and the return system. The hose 61 is flexible to enable adjustment of the cleaning means’ 3 position. The front cleaning means 3a may also be connected to the return system. The effluent may be transported from the return system to the return reservoir via a hose 60 connected to the ROV 9. In the figure, the hose 60 is connected to an underside 902 of the ROV 9.

Figure 10 further shows that the cleaning means 3, 3a comprise a connection 70 for a highpressure liquid supply. The high-pressure liquid supply system is not depicted in the figures. The connection is in fluid communication with the nozzles 35 on the respective cleaning discs 32.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb "comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Claims (13)

C l a i m s

1. A cleaning apparatus (1) for cleaning a submerged portion of a structure (100), the cleaning apparatus (1) comprising:

- a frame (2) comprising a first side portion (202), a second side portion (203) and a longitudinal axis (10);

- a plurality of cleaning means (3) connected to both the first side portion (202) and the second side portion (203) of the frame (2), wherein each cleaning means (3) has a centre (300) and an adjustable orientation relative to the frame (2),

c h a r a c t e r i s e d i n that at least one coupling unit (7) is connected to at least two cleaning means (3) on the same side portion (202, 203).

2. The cleaning apparatus (1) according to claim 1, wherein a distance from the centre (300) of at least two cleaning means (3) to the longitudinal axis (10) are different when having the same orientation relative to the frame (2).

3. The cleaning apparatus (1) according to claim 1 or 2, further comprising a centre cleaning means (3a) arranged with the centre (300) substantially in line with the longitudinal axis (10) of the frame (2).

4. The cleaning apparatus (1) according to any of the claims 1-3, further comprising a rotatable cleaning disc (32) connected to each cleaning means (3), the cleaning disc (32) comprising a rotational axis (301), a cleaning side (33), a back side (37) opposite the cleaning side (33), a peripheral portion (310) and at least one nozzle (35) for emitting a fluid jet (4), the nozzle (35) being in fluid communication with a fluid reservoir.

5. The cleaning apparatus (1) according to claim 4, wherein the cleaning disc (32) comprises a plurality of nozzles (35), and wherein the fluid jet (4) emitted from each nozzle (35), in use, form an angle relative to a radial direction of the cleaning disc (32), said angle being different for each fluid jet (4).

6. The cleaning apparatus (1) according to claim 4 or 5, wherein the nozzle (35) are arranged in the peripheral portion (310).

7. The cleaning apparatus (1) according to any of the claims 4-6, wherein the rotatable cleaning disc (32) further comprises at least one recess (36) in the peripheral portion (310), the recess (36) having a bore (360) arranged angularly relative to the rotational axis (301) and the radial direction of the cleaning disc (32), wherein the recess (36) provides a channel for a surrounding liquid to flow from the cleaning side (33) to the back side (37) of the cleaning disc (32).

8. The cleaning apparatus (1) according to any of the preceding claims, further comprising a return system, wherein the return system is configured to, in operational use, transport effluent from cleaning from the cleaning means (3, 3a) to a return reservoir.

9. The cleaning apparatus (1) according to any of the preceding claims, further comprising sensor equipment for detecting obstacles in the water.

10. The cleaning apparatus (1) according to any of the preceding claims, further comprising an attachment for connection to a remotely operated vehicle (9).

11. A cleaning vehicle (19) comprising the cleaning apparatus (1) according to any of the preceding claims and a remotely operated vehicle (9), wherein the remotely operated vehicle (9) is configured for relocating the cleaning apparatus (1) in water.

12. Use of the cleaning apparatus (1) according to any of the claims 1-9 for cleaning a submerged portion of a structure (100).

13. Use of the cleaning vehicle (19) according to claim 10 for relocating the cleaning apparatus (1) in water.