Field of application

This invention refers to plants with an improved washing unit for washing and cleaning the hulls of ships, or rather plants located at ports, docks or piers, or in natural harbours, that include means for intervening upon the submerged hulls of the ships to be treated, which are positioned, by manoeuvring the plant, to embrace the hull of the ship to be treated, and act in a quick, economical, and semi-automatic or automatic fashion in carrying out the cleaning operations, which are designed to eliminate any dirt, vegetation or “fouling” present on the submerged part of a ship’s hull. There is also a way of use these cleaning and washing systems with an improved washing unit.

Known art

The state of the art includes various types of systems for cleaning the hulls of ships, which include various forms of semi-floating or floating basin plants designed to guide the means of washing and cleaning the hulls of the ships being treated while the ships are stationed in the area of the plant itself.

The art includes known designs of ship hull washing and cleaning plants, in which the washing water is immediately collected by a filtration device after being used to remove vegetation from the hull, and is then returned to the port free of any dirt, vegetation or“fouling.”

Furthermore, document EP 1060983 A1 refers to a cleaning system consisting of water jet nozzles, roller-shaped rotary brushes, and other cleaning devices. The washing area consists of the inner part of a floating basin moored to a quay, with the opening and closing of the relative area being delimited by bulkheads, which are lowered during the passage of the vessel. The body of the vessel in the washing area is held in place by supports, and the washing and cleaning equipment slides along the inside of the floating basin in order to treat the entire surface of the hull. The area inside the basin is then closed off at each end by two bulkheads in order to retain and purify the washing water. Although this plant already provides for the treatment and filtering of washing water, it is not suitable for various kinds of boats, both small and large, since the cleaning equipment moves along separate carriages within the floating basin, and the washing and cleaning operations, which take place with the boat floating, involve a large amount of water to be purified inside the basin. The cost of such a floating basin system is therefore rather high if designed for medium or large ships, while the amount of water to be purified is quite large in proportion to the size of the vessel’s hull.

The state of the art also includes document WO 9702983 A1 , which describes a floating basin suitable for cleaning the hulls of ships, with a ship hull cleaning method in which the floating basin is ballasted and rendered independent by its own motorisation. The floating basin includes equipment for receiving a ship’s hull, is essentially built in the shape of a U, and can be at least partially submerged so that a base portion, including the cleaning equipment, can be positioned underneath the hull of the ship. The lateral cleaning equipment is present on at least one interior side of the ship’s hull, and the receiving equipment can be adjusted to accommodate the shape of the hull itself, so that it comes into contact on one side of the ship’s hull. There are means for adjusting the position of the side and lower cleaning equipment, in order to allow them to basically follow the contours of the ship’s sides and hull. There are means for collecting the debris removed, with the water being collected during the cleaning operations and subsequently discharged in a remote location.

This prior plant described above also does not allow to embody of a plant that offers easy of use for quickly, economically, and effectively eliminating encrustations and marine vegetation from the hulls of small, medium or large-sized ships, while retaining, purifying and discharging the waste water when and where required, with the washing water and dirt being discharged directly into the port where the ship hull washing and cleaning system is located and operates, since there is no boundary between the space inside the basin and the surrounding seawater.

The art also includes ship hull cleaning systems in which one or more devices adhering to the submerged part of the hull are utilised, which cover a fairly small surface area; these are automatically moved to the various parts of the hull in succession, in order to clean a large portion of the ship’s hull, as described in document WO 0032467 A1. The device includes equipment designed to slide over the surface of the hull and mechanical equipment for cleaning the portion of the hull inside the compartment covered by the device, including pressurised water jets and localised suction to more effectively collect the dirty water. The device is connected to the necessary pipes for collecting the washing water and eliminating the water mixed with the removed dirt, which is conveyed and collected for subsequent filtering and controlled disposal.

The operations carried out by such devices are also rather slow in relation to the time frames for which the ships are able to remain in port, and cannot be carried out at the dock, even taking several hours to properly clean the hulls of large transport ships.

The aforementioned ship hull cleaning and washing systems are therefore insufficient, and do not provide for the continuous cleaning necessary to eliminate the dirt, marine vegetation, and“fouling” that continuously forms on the hulls of ships while stationed in ports and, to a lesser extent, during navigation. In fact, the ships that most require hull cleaning and washing are also subject to intensive use for the transport of merchandise, liquid products, or even passengers, including container carriers, tankers, and passenger vessels, and therefore do not have time to undergo the lengthy operations necessary to have their hulls thoroughly cleaned. Finally, these plants must comply with the local anti-pollution regulations, which require waste waters to be discharged in a controlled manner, but prohibit the discharge of waste from hulls coated with certain poisonous anti-vegetative paints.

The collection and elimination of the water polluted by dirt, marine vegetation or “fouling” must therefore take place in a nearly comprehensive manner and with limited amounts of treated water in order to avoid the need for excessively large water pumping and filtering equipment, while at the same time managing the ways in which the parts of the ship hull washing and cleaning plant are used in order collect the dirt or“fouling” in the most effective manner possible. This state of the art could be significantly improved with regard to the possibility of obtaining an improved washing unit for ship hull washing and cleaning plants, with a washing unit that overcomes the aforementioned drawbacks, and is able to be used for washing and cleaning ship hulls, providing for a significant reduction in treatment time, and ensuring maximum collection for the purpose of filtering and disposing of the waste waters containing the dirt, vegetation or“fouling” removed from the ships’ hulls.

The technical problem underlying this invention therefore consists of obtaining a ship hull washing and cleaning system with an improved washing unit that has an effective ability to separate, collect and purify the water that comes into contact with the ship’s hull during the treatment during the ship hull washing and cleaning operations, and is affordable in terms of construction and operating costs while at the same time ensuring effective functionality.

Another purpose of this invention is to achieve a plant that is able to effectively capture or collect water, while at the same time adapting to the hulls of ships of various sizes.

In order to achieve the above objective in the most effective manner, the invention must limit and reduce the quantity of water that comes into contact with the ship’s hull during the treatment, in order to facilitate its rapid collection for filtration and disposal.

Another objective of this invention is to realise a composition of equipment for the ship hull cleaning and washing plant that is able to adapt to the needs of various types of cleaning plants, including those equipped with washing units operating in connection or in proximity to the docks at the ports, as well as the floating and manoeuvrable types operating in harbours or in areas where ships are required to stop or transit.

Finally, in order to eliminate all the problems faced by ship hull cleaning and washing plants, it is necessary to limit the amount of water involved in the ship hull washing process by offering the possibility of performing intermittent and continuous cleaning and washing treatments in both automatic and semi- automatic mode. Finally, in order to overcome the technical problem as outlined, it is necessary to establish a usage method for the ship hull cleaning and washing plants built using the specific parts described herein and specified below.

Summary of the invention

According to this invention, this technical problem is resolved by a ship hull washing and cleaning plant with an improved washing unit comprises: submerged cleaning and washing equipment positioned below the water line and operating against the hull; systems for positioning the plant as it engages with and washes the entire length of the hull; systems for controlling and adjusting the plant’s displacement with immersion level control; the structure of the plant also includes a walled basin inside which the cleaning and washing equipment is positioned to form a washing unit; this basin is characterised by the fact that the cleaning and washing equipment is arranged therein and is brought into contact with the hull during the cleaning operations, with the floating of the plant and the positioning of the cleaning and washing equipment’s support elements being controlled in relation to the basin itself; the cleaning and washing equipment is accompanied by extraction openings for collecting the dirty post-treatment water; guidance systems for engaging and positioning the ship during the treatment;the cleaning and washing equipment is moved along the hull during the treatment via the movement of the basin, or rather the movement of the washing unit itself; the cleaning and washing equipment simultaneously works upon the section of the hull covered by the length of the washing unit; in the section of the hull being treated, there is at least one movable bulkhead on each end of the washing unit in order to create a boundary between the section of hull being washed and the surrounding seawater, and to facilitate the water’s collection and the elimination of the dirt, vegetation or“fouling” removed from the hull and polluting the water between the bulkheads; the movable bulkheads consist of flexible bulkheads with inflatable upper edges for controlling the displacement of the bulkhead itself, which are equipped with sliding contact elements or rollers for sliding against the hull; the movable bulkheads are accompanied by a pipe for extracting the dirty water generated during the treatment, which is positioned towards the inside of the washing unit near the inflatable edge in contact with the hull undergoing treatment, with the extraction holes facing the surface of treated hull.

On one specific variant: the section of extraction pipe near or above the water’s surface is even equipped with a special blocker designed to prevent air from entering the extraction holes.

On another variant: the extraction hole blocker is present inside the extraction pipe itself, and consists of a pipe with an inflatable casing inserted inside the extraction pipe designed to block the extraction holes; the internal blocker can be adjusted as necessary based on the position of the water extraction pipe by deflating and inflating its casing, since it is able to move inside the water extraction pipe when deflated.

One variant of the previous design has an external extraction hole blocker; this external blocker is movable and is positioned to cover the section of the extraction pipe that remains near or above the water’s surface during the placement of the flexible and inflatable bulkheads.

On yet another design variant: the flexible bulkheads consist of a pair of double bulkheads and are positioned at the ends of the washing unit in order to allow for the extraction of the water between the two bulkheads of the paired bulkheads, as well as inside the section covered by the washing unit during the washing and cleaning of the hull.

On yet another variant: when using the bulkhead near the bow or the stern of the ship being treated, the flexible bulkhead’s inflatable support and manoeuvring edge is accompanied by short inflatable walls that extend when inflated to fill or minimise the gap between the inflatable bulkhead’s inflatable support edge and the surface of the hull at the bow or the stern of the ship, which typically has concavities that cannot be obstructed by the bulkhead’s inflatable support edge alone, thus limiting the spaces through which water is able to pass.

On another specific variant: the guiding elements for engagement and positioning during the treatment process include mechanical spacers between the floor of the washing unit and the hull above, as well as adjustable mechanical spacers that can be positioned based on the specific shape of the hull to be treated; there are even lateral pushers with regulating arms and rollers designed to make contact with the hull or its walls, which gauge the positioning of the washing unit prior to its engagement of the hull to be treated.

On an even more advanced version: the flexible bulkheads or even the pair of flexible bulkheads are respectively manoeuvred by the single or, for the double bulkheads, the paired inflatable edge support, which is sustained at the support point near the hull being treated by a telescopic arm, or on one end by the telescopic arm and by at least a pair of rollers specifically shaped to come into contact with the inflatable edge or pair of inflatable edges.

On yet another specific version: the end of the telescopic arm supporting the inflatable edge and the bulkhead connected to it is shaped in such a way as to accommodate the connected water extraction pipe, which moves together with the inflatable edge with which it is associated; the extraction pipe is therefore able to be manoeuvred with the shaped end of the telescopic arm itself, along with the inflatable edge.

One adopted variant even has the external blocker fixed to the shaped end of the arm, and is able to be moved with it together with the shaped rollers during the positioning of the inflatable edge, to which the water extraction pipe is secured via connections to the end of the shaped arm; the external blocker thus moves together with the shaped rollers supporting the inflatable edge, which are positioned at the level of the water inside the washing unit.

On a preferred design variant, the connection between the flexible bulkhead and the end of its inflatable support and manoeuvring edge is able to slide for a length compatible with the length of the inflatable edge, which is positioned outside the washing unit in order to allow the flexible bulkhead to slide and bend, thus allowing the flexible bulkhead to be manoeuvred while maintaining its connection with the floor and the side of the washing unit.

The design of the washing and cleaning plant has been completed with the following: the cleaning and washing equipment is associated with outlets that emit water at a controlled temperature greater than that of the sea water in the washing unit, thus allowing the movement of the water against the hull, which is pushed or sprayed by said cleaning and washing equipment, to be detected via thermal imaging cameras. Moreover, on one specific design variant: the cleaning and washing equipment, together with the associated controlled-temperature water outlets in the washing unit, are able to be moved together with the extraction openings in order to verify the movement of the water against the hull with said thermal imaging cameras, and to ensure the collection of the dirty water with the extraction openings; the emission of controlled-temperature water is carried out in places where aggressive hull washing and cleaning activity is required.

An advantageous method of use of ship hull cleaning and washing plants, carried out in accordance with the definitions contained of one or more of the preceding cases, includes:

the engagement of the ship’s hull to be subjected to hull cleaning and washing within the hull cleaning and washing plant, with setting mechanical spacers aligned with the hull line, also the adjusting mechanical spacers and the lateral pushers and their regulating arms;

the positioning of the flexible bulkheads at the ends of the washing unit present within the plant near the section of hull to be cleaned by manoeuvring them using the inflatable support edges, even allowing for the presence of limited gaps around the edges of the bulkheads themselves, without creating a water-tight seal;

the positioning of the washing and cleaning equipment near the section of hull concerned, and the execution of the washing and cleaning process;

the extraction of the dirty water generated in the vicinity of said washing and cleaning equipment as a result of the washing and cleaning process;

the extraction of the dirty water present in the space occupied by the washing unit through the extraction openings present on the floor and/or sides of the washing unit;

the filtration of the extracted water and its reintroduction into the area of the washing unit, while limiting but also facilitating the entry of water from outside the flexible bulkheads through the limited gaps around the edges thereof, and through the inflatable edge’s imperfect contact with the hull being treated;

the release of the excess filtered water outside the washing unit and its flexible bulkheads, provided that the depressurisation of the stretch of water occupied by the section of hull being washed is maintained, so that water continues to enter from outside the flexible bulkheads, thus preventing the dispersion of dirty water outside the washing unit;

once the washing treatment of the section of the hull covered by the washing unit has been completed, the continuous movement of the washing unit, mainly over the portion of the hull with a constant conformation, or its intermittent movement near the bow or stern of the ship, with the flexible bulkheads and the inflatable edge, as well as the cleaning, washing and dirty wash water extraction equipment being adjusted to the specific conformation of the section of the hull being treated;

once the hull washing has been completed, the disengagement of the washing unit and the ship hull washing and cleaning plant from the hull.

Finally, in a specific and preferred variation of the aforementioned method of use: in order to proceed with the thorough and verifiable washing of the hull, water at a temperature greater than the water within the washing unit is released in the vicinity of the washing and cleaning equipment and the hull being treated; at the same time, thermal imaging cameras are used to detect and visually record the movement of the warmer water against the hull being washed and cleaned, with the effectiveness of the operations being verified through the collection of the water through the extraction openings positioned near the washing and cleaning equipment itself; this high temperature water is also used to carry out aggressive washing and cleaning operations on particular points of the hull, both for degreasing purposes and to eliminate any particularly resistant incrustations of marine vegetation.

The features and advantages of this invention, consisting of the realisation of a ship hull washing and cleaning system equipped with an improved washing unit and its method of use, are mentioned in the descriptions below of several schematic examples of its application, provided by way of example and without limitation, with reference being made to the sixteen drawings attached. Brief descriptions of the drawings

Figure 1 shows a schematic cross-sectional view of a ship hull washing and cleaning plant, built according to the invention, in which a washing unit is positioned within a semi-floating basin, whose continuous or intermittent sliding movement is controlled by guides connected to the dock to which the ship being treated is moored; the drawing depicts one of the at least two flexible and inflatable bulkheads that delimit the washing unit’s washing position on the hull of the ship, here shown in the lowered position;

- Figure 2 shows a schematic cross-sectional view of the plant in Figure 1 , in which the flexible and inflatable bulkhead is raised against the hull of the ship being treated;

- Figure 3 shows a schematic frontal view of a ship next to the hull engagement equipment built according to the invention, consisting of washing units or floating basins, in order to rapidly and securely centre the hull during its engagement with the washing unit;

- Figure 4 shows a schematic cross-sectional view of a semi-floating ship hull washing and cleaning plant similar to that in Figure 1 , in which the means for engaging the hull in Figure 3 are applied directly to the washing unit mounted on this plant, and the washing unit is rendered transversally mobile with respect to the plant’s floor;

- Figure 5 shows a schematic plan view of a floating, semi-submerged and manoeuvrable ship hull washing and cleaning plant, built according to the invention, in which the means for engaging the hull is shown both on the floor of the plant and protruding from the lateral walls of the washing unit housed between the short walls within the plant; the means of engagement protruding from the sides are shown regulated for the two dimensions of a ship that can be treated by this plant, maximum hull size on one side, and minimum hull size on the opposite side;

- Figure 6 shows a schematic frontal view of the hull guiding elements protruding from the sides of the floating and manoeuvrable plant in Figure 5 only, and highlights them on the two sides of the hull, regulated for the minimum and maximum dimensions of the hull being treated by the plant in Figure 5; - Figure 7 shows a schematic cross-sectional view of the floating, semi- submerged and manoeuvrable system in Figure 5, in which the lateral hull engagement elements are highlighted; the drawing also shows the hull washing and cleaning equipment positioned between the walls; in the two halves of the figure, the engagement and washing elements are shown regulated for the maximum and minimum dimensions of the hull of a ship that can be treated by this plant;

- Figure 8 shows a schematic view of one side of a vessel engaged with a plant built according to the invention, highlighting the washing and cleaning equipment, the elements for engaging with the ship’s hull, and the guiding elements for the semi-floating basin and the washing unit, which are shown on tracks, along a dock where the ship is being treated;

- Figure 9 shows a schematic view of one side of a vessel engaged with a floating, semi-submerged and manoeuvrable plant built according to the invention, highlighting the washing and cleaning equipment, the elements for engaging with the ship’s hull, the guiding elements for the basin and the washing unit, and the equipment for extracting and collecting the water from the space inside the washing unit working on the ship;

- Figure 10 shows a schematic plan view of a ship engaged with a floating, semi-submerged and manoeuvrable system like than in Figure 5, highlighting the positions of the washing and cleaning equipment, the elements for engaging with the ship’s hull, and the elements for guiding the basin and the washing unit; the plant is depicted during the washing process, and at the end of the washing process during the disengagement phase from the bow of the treated ship;

- Figure 11 shows a longitudinal schematic view of the plant in Figure 8, enlarged and limited to the plant’s mobile structure during the washing and cleaning of the ship’s hull, highlighting the washing and cleaning equipment, the elements for engaging with the ship’s hull, the guiding elements for the basin and the washing unit, and the equipment for extracting and collecting the water from the space inside the washing unit, like in Figure 9;

- Figure 12, moreover, shows a longitudinal schematic view of the plant in Figure 9, enlarged and limited to the floating, semi-submerged and manoeuvrable structure, during the washing and cleaning of the ship’s hull;

- Figure 13 shows a schematic frontal view of a washing unit built according to the invention, in which the rotary brush units more or less longitudinal to the hull are shown operating on both the bottom and the walls of the hull itself;

- Figure 14 shows the enlarged 14th portion of Figure 13 above, highlighting the rotational motions of the aforementioned rotary brushes and the wash water collection openings in the vicinity of the rotary brushes themselves, which are kept equidistant from the same;

- Figure 15 shows the enlarged 15th portion of Figure 13 above, highlighting the rotational motions of the aforementioned rotary brushes and the wash water collection openings in the vicinity of the rotary brushes themselves, like in Figure 14;

- Figure 16 shows a schematic plan view of a floating, semi-submerged and manoeuvrable ship hull washing and cleaning plant, like in Figure 5, in which the means for engaging the hull is shown both on the floor of the plant and protruding from the lateral walls of the washing unit housed within the plant; the positioning of the means of engagement on the floor can be regulated to engage with the specific hull in the most convenient position; the means of engagement protruding from the walls are also able to be regulated by rotation on a vertical axis; in addition, the washing unit with rotary brush washing elements more or less longitudinal to the hull inserted within the washing unit is delimited by inflatable bulkheads on the section of hull being treated; there are also thermal imaging cameras positioned between the bulkheads and the rotary brushes in order to detect the correct motion of the water during the washing and cleaning operations;

- Figure 17 shows a schematic cross-sectional view of the floating, semi-submerged and manoeuvrable plant in Figure 7, highlighting the locations of the thermal imaging cameras near the surface of the hull being treated, as seen in Figure 16;

- Figure 18 shows a schematic plan view of a floating, semi-submerged and manoeuvrable ship hull washing and cleaning plant, like in Figure 5, in which the means for engaging the hull is shown both on the floor of the plant and protruding from the lateral walls of the washing unit housed within the plant; the positioning of the means of engagement on the floor can be regulated to engage with the specific hull in the most convenient position; the means of engagement protruding from the walls are able to be regulated even by rotation on a vertical axis; in addition, the washing unit has washing elements with belts equipped with washing jets pointing towards the hull and able to be moved longitudinally in relation to it within the washing unit during the washing process;

- Figure 19 shows a schematic frontal view of a flexible and inflatable bulkhead for the washing unit built according to the invention, in which the bulkhead is regulated for contact with the smallest hull size able to be treated by the plant upon which it is mounted; the means of manoeuvring the inflatable bulkhead contained and supported by the walls are highlighted;

- Figure 20 shows a schematic frontal view of a flexible and inflatable bulkhead for a washing unit like that in Figure 19, which in this case has been regulated for contact with the largest hull size able to be treated by the plant upon which it is mounted;

- Figure 21 shows a schematic frontal view of a washing unit like that in Figures 19 and 20 above, divided into two halves in different hull positions, where the inflatable bulkhead is positioned near the bow of the ship (left part of the Figure), and is equipped with an additional inflatable element overflowing the inflated bulkhead to block the concavity of the bow near the bow bulb;

- Figure 22 shows a schematic cross-sectional view of an inflatable bulkhead edge being supported by the positioning rollers on the support end near the hull being treated, or wherever necessary to support the inflatable bulkhead, as depicted in Figures 19-21 above, and also to allow for the manoeuvre of lifting it against or lowering it away from the hull;

- Figure 23 shows a schematic side view of a flexible and inflatable bulkhead with an additional inflatable element overflowing the inflated bulkhead to block the concavity of the bow near the bulb, as shown in Figure 21 ;

- Figure 24 shows a frontal schematic view limited to a washing unit from the plant depicted in Figure 1 or 2, built according to the invention, in which the flexible and inflatable bulkhead is equipped with an extraction pipe with an out- of-water blocker for extracting the water polluted with dirt, vegetation or“fouling”, detached from the hull between the bulkheads, which delimit the washing unit itself; in this figure, the top edge of the inflatable flexible bulkhead is also equipped with sliding rollers in order to allow the bulkheads to operate continuously upon the hull to be treated, in such a way that they can be moved intermittently or slowly against the hull itself during the treatment with no need to detach the flexible and inflatable bulkhead itself;

- Figure 25 shows an enlarged schematic view of the detail in Figure 22 in order to highlight the upper position of the end blocker on the extraction pipe connected to the flexible and inflatable bulkhead, but in a limited position just below the water’s surface;

- Figure 26 shows a schematic cross-section of the flexible and inflatable bulkhead, positioned against the submerged hull and equipped with a pipe for extracting and collecting the dirty water generated during the washing and cleaning of the hull itself, in this case equipped with sliding rollers against the hull;

- Figure 27 shows a schematic cross-section of the flexible and inflatable bulkhead, positioned against the submerged hull and equipped with a pipe for extracting and collecting the dirty water generated during the washing and cleaning of the hull itself, in this case with a rub layer for sliding against the hull;

- Figure 28 shows a schematic cross-section of an inflatable bulkhead edge being supported by the positioning rollers on the support end near the hull being treated, in which a perforated and connected water pipe with an external blocker is also present and regulated with positioning at the end of the bulkhead, near the surface of the water inside the washing unit;

- Figure 29 shows a schematic cross-section of an inflatable bulkhead edge being supported by the positioning rollers on the end of the bulkhead itself, like in Figure 29, but in this case equipped with a blocker inside the pipe that can be inflated to adjust the position reached when manoeuvring the end of said bulkhead at water level within the washing unit;

- Figure 30 shows a schematic view next to an arrangement of flexible and inflatable double bulkheads on opposite ends of a ship hull washing unit; with the possibility of extracting the water to be purified from between the bulkheads of each pair;

- Figure 31 shows a schematic cross-section of the inflatable edges of the double bulkheads in Figure 30 supporting the double bulkhead positioning rollers, like in Figure 22, but in this case made to support the end of the double bulkhead in the washing unit;

- Figure 32 shows a schematic view next to an arrangement of flexible and inflatable bulkheads, arranged in pairs on opposite ends of a ship hull washing unit, like in the previous Figures, with a pipe for collecting and extracting the polluted water generated during the washing of the hull positioned between the pair of bulkheads; the drawing shows a lower line of the hull and the lines of the water level inside and outside the washing unit, and between the pair of flexible and inflatable bulkheads;

- Figure 33 shows an enlarged schematic view of the portion of Figure 32 above, highlighting an extraction pipe connected to the inflatable edge of the pair’s outer bulkhead, and with a manoeuvrable and adjustable internal blocker positioned for the perforated extraction pipe’s holes that are near or above the surface of the water inside the washing unit.

Detailed description of a preferred configuration

Figures 1 and 2 show an improved ship hull washing and cleaning plant

1 installed on a pier M where a ship 2 has been docked to undergo the cleaning treatment while remaining floating on the water L. The plant 1 includes a washing unit 4 housed within a semi-floating open basin structure 5 that’s able to slide parallel to the pier M along on rails or tracks 6 affixed to the pier M itself; the open basin has an external wall 7 connected to the structure and an internal wall 8, towards the pier M, which is equipped with elements for sliding along the aforementioned tracks 6. The washing unit 4 has a structure S that’s enclosed on the sides F and the bottom P. The Figures show floating chambers 9 joining the outer wall 7 to form the structure of the open basin 5, which are connected to the inner wall 8 by a vertically sliding carriage 10, and allow for their displacement for controlled floating on the tracks 6 affixed to the pier M, or for compensation in order to keep the open basin 5 submerged at the correct depth for the engagement/disengagement operations 3 with the hull of the ship to be cleaned and during the hull cleaning operations themselves. Said floating chambers 9 are properly controlled by a process computer, and compensate for the buoyancy of the open basin 5 by avoiding generating vertical thrusts on the rails or tracks 6, regardless of whether or not there is a ship engaged in the plant, or even during the cleaning treatment. Furthermore, during the docking and cleaning of the hull, the same may have a hull line X that is not always parallel to the pier M, and a horizontal carriage N for transversally adapting to the hull line is therefore provided for the structure S of the washing unit 4, in order to verify the proper distance and action of the cleaning and washing equipment utilised, which is thus positioned correctly on the hull 3.

In Figure 3, the ship’s hull 3 is guided in its engagement with the washing unit 4 by at least one mechanical spacer 17 that rotates the hull’s X axis with respect to the longitudinal axis of the plant 1 , the open basin 5, and the washing unit 4; the extension of these elements is controlled by the floor or bottom P of the washing unit in order to detect the positioning of the hull 3 in relation to the plant 1 and to continuously monitor both the displacement of the plant and the positioning of the cleaning and washing equipment 14, even during the hull treatment stage; the plant’s guidance during the engagement of the hull is carried out by centring the washing unit with the lateral hull guidance supports at water level L, which consist of large, robust, rubber-coated idle rollers on a vertical axis; after engagement, the ship’s centring with the washing unit is maintained by lateral pushers 19 projecting towards the centre of the washing unit 4 from its sides F: the arms of the pushers end with 20 rollers intended to come into contact with the walls 26 and hull 3 of the ship 2 engaged during the treatment; the operators in charge control the engagement and treatment operations carried out by the plant 1 upon the hull 3 of the ship 2 from the bridge 22, regardless of whether the operation is carried out semi-automatically, or whether the direction of engagement, the displacement of the plant, and the phases of the treatment are controlled automatically by the on-board computer, which controls the buoyancy, the manoeuvring and the floating and manoeuvrable plant’s treatment operations as per the invention. The section of the hull involved in the cleaning treatment is in contact with the cleaning equipment 14, as shown in Figure 4, with rotary brushes 13 on an axis more or less parallel to the hull, and is delimited by flexible bulkheads 16 inside the washing unit 4, in order to ensure the extraction of the water containing the washing debris; said bulkheads can be inflated on command in order to be raised along the stretch of hull undergoing treatment until they reach the section involved and press against it to prevent any exchange of water with that outside the section of the hull to be treated by the washing unit. The arrangement and functionality of the aforementioned flexible bulkheads 16 is depicted at water level L. Moreover, the water extraction is carried out inside the washing unit 4 directly in the vicinity of the cleaning elements, in order to keep the bottom of the washing unit free of any debris; the bottom or floor P of the washing unit 4 contains at least one waste water extraction opening A, and an extraction pipe T allows it to be extracted by the pumps into the auxiliary compartments 15 for the required treatment. In the variant shown in Figure 4 the rails and tracks 6 are affixed indirectly to the pier M. In fact, a wall 11 is affixed vertically to the pier M itself, and the rails or tracks 6 are affixed to the wall.

In Figure 4, the washing unit 4 depicted is even the type with rotary brushes 13, with an axis more or less parallel to the hull; the plant also has auxiliary compartments 15 for the mobile housing of machinery components, such as wash water pumps, and filters for purifying the extracted washing and cleaning of the dirt removed from the hull and collected; the enclosed structure S of the washing unit 4 facilitates the containment of the water mixed with the debris removed during the treatment and its extraction for evacuation or filtration via a pipe T.

The plant 1 is completed with elements for mooring 23 the ship 2, as seen in Figure 4, which consist of connection arms 24 designed to slide on positioning guides 25 between the pier itself M and the wall 26 of the ship 2. The connection between the respective connection arm 24 and the hull of the ship is obtained by activating an electromagnet 27, which holds the sheet metal wall firmly in place with respect to the open basin 5 for the duration of the cleaning and washing treatment. The magnetic field generated by the electromagnet 27 provides for a strong bond between it and wall 26, which remains limited to the area between the wall and the electromagnet itself, without affecting the surrounding environment. For the treatment of ships with walls not made of magnetic metal, there are other docking systems that can be utilised, which involve the use of suction cups and vacuum pumps powerful enough to hold the ship 2 in place. The arms 24 can also be used as simple fixed contact points or stoppers for determining the proper positioning of the ship, which therefore will not be moored and stationed against the pier’s bumpers, but against the bumpers of the arms 24 themselves. The operational phases of the plant on the pier M are controlled and commanded from a bridge 22, which consists of the movement control and monitoring elements, like the process computer, which uses the plant’s floating sensors, the sensors for determining the size of the ship’s hull, and the type of washing unit 4 present in the plant, to give the plant’s displacement commands, thus ensuring the proper operation of the cleaning equipment and the proper positioning between the ship 2, the cleaning plant’s equipment, and the washing unit at all times.

Figures 5, 6 and 7 show a floating and manoeuvrable ship hull cleaning plant 31 complete with a basin 32, included in this invention, consisting of short walls 33 and a floor 34 joining the walls, within which the washing and cleaning equipment is positioned 35; this equipment consists of rotary brushes 36 with an axis more or less parallel to the ship’s hull, or even belts with multiple nozzle jets 37, shown in Figure 18, which spray high-pressure water onto the hull; both the rotary brushes 36 and the belts with multiple jets 37 are supported, in relation to the walls and the floor, by mobile support elements positioned vertically 38 and/or horizontally 39; the walls and the floor contain floating chambers 40 for the computerized control of the plant’s displacement, and technical compartments for housing the washing and cleaning equipment’s movement elements, both for displacement, such as the hydraulic drive systems for the mobile supports used to position the brushes 36 and the belts with multiple jets 37, as well as for operation, such as the pumps for delivering the washing and filtration water, or for turning the rotary brushes 36; the floor also contains, into the thickness, longitudinal 43 and transverse 44 propulsion elements for manoeuvring the floating plant 31 during its engagement with the hull of the ship, and for moving along the hull, in order to provide the intermittent or continuous advancement motion during the washing and cleaning treatment.

In order to allow for the engagement of a hull 3 within the floating and manoeuvrable plant 31 , there are side supports 18 and lateral pushers 19 capable of being adjusted and oriented on a vertical axis at the end of the lateral pushers’ regulating arms 21 ; said regulating arms contain rollers 20 for making contact with and guiding the plant against the walls of the hull 3; these rollers 20 are present during the mechanical spacers’ 17 contact with the hull, in order to maintain the proper distance between the floor 34 and hull 3 during the engagement and treatment processes. The rollers and mechanical spacers are also positioned laterally on the floor 34 with respect to the centre of plant 31 and the hull line X of the ship that has been or will be engaged. There is a flexible and inflatable bulkhead 42 at each end of the washing equipment 35 on the floating and manoeuvrable plant’s 31 washing unit 41 , which delineate a narrow area of water next to the hull where the washing and cleaning of that section of hull are carried out, thus minimising the possibility that the dirty water generated during the washing and cleaning operations will contaminate the water outside the section of hull being washed.

Figures 8, 9, 10, 11 and 12 show the positions of the equipment used for engagement, for positioning the washing equipment, and for delimiting the section of the hull of a ship undergoing treatment. The figures consist of various layout and side views of both the semi-floating plant 1 , in Figures 1 -4, and the floating and manoeuvrable plant 31 , in Figures 5-7. Each contain references to the parts already described above, both similar and identical. Figure 10 also shows the anchoring 30 of the ship 2 during engagement and up until the end of the hull washing and cleaning treatment; the anchoring will only be released at the end of the treatment in order to free the floating and manoeuvrable plant 31 from its engagement with the ship being treated.

The above figures also show the water level LB in the section undergoing treatment, which is slightly below the water level L outside the flexible and inflatable bulkheads 16 or 42 due to the effect of the extraction of the dirty water generated during the washing and cleaning treatment, which is drawn in by the water extraction and filtration system’s openings. The extraction of the water to be collected and filtered by the openings on the bottom of the washing unit and the openings near the washing equipment, whether consisting of rotary brushes 13 or 36 or belts with multiple jets 37, in order to collect the water to be filtered precisely where it forms, also takes place through water extraction pipes 45 near the flexible and inflatable bulkheads, which are connected to the inner part of the same bulkheads and are equipped with water extraction holes 46, which can be seen in the following figures; all of these extraction openings, whose suction power has been properly balanced, result in a slight drop in the water level LB between the bulkheads delimiting the section of hull undergoing treatment, thus allowing for water to get in, while at the same time preventing dirty water from spilling over the bulkheads. Therefore, since the ends 47 of the flexible and inflatable bulkheads are out of the water but close to the hull 3 undergoing treatment, blockers 48 have been positioned to prevent air from entering the water extraction holes 46 during the collection of the water close to the water's surface. These 48 blockers, which are advantageously external and wrap around the water extraction pipe 45, are mobile and are positioned to cover the tract of the extraction pipe 45 near the water level or that which remains above water level during the placement of the flexible and inflatable bulkheads 16 of 42 on the specific section of hull 3 to be washed, and are regulated each time the bulkheads or the washing unit 4 or 41 are moved.

In Figures 13-15, the washing unit depicted 41 has rotary brushes 36 with an axis more or less parallel to hull 3, and, near each of the individual brush’s vertical manoeuvring elements 38, has at least one water extraction opening 49 close to the space occupied by the supported rotary brush. In the figure, each horizontal moving element 39 for supporting and horizontally moving the rotary brush, or groups of rotary brushes, against the hull of the ship undergoing treatment is paired with at least one extraction opening 49 near the supported rotary brush(s). The rotary brushes positioned side-by-side operate advantageously with opposite directions of rotation, as shown in the Figures. Although the above figures refer to the washing unit 41 , the extraction openings 49 can also be applied to the washing unit 4 in Figures 1 -4.

The variants of Figures 5 and 7 shown in Figures 16-18 show additional variants of the floating and manoeuvrable plant 31 in which similar or identical parts are shown with the reference numbers previously indicated. The cleaning and washing equipment 35 is shown with the belts with multiple jets 37, which are rendered mobile between the flexible and inflatable bulkheads 42 along the floor 34 of the washing unit 41 ; the belts with jets 37 are mounted on tracks 50 within the washing unit, and their positioning is controlled by the process computer, which manages the movements of the cleaning and washing elements. In addition, the mechanical spacers between the hull 3, the washing unit and the floor 34 of the plant 31 are adjustable mechanical spacers 51 for use with hulls that require a distance control not limited to the hull line X, but require support with multiple mechanical spacers positioned in different locations based on the specific shape of the hull 3 itself; however, as previously indicated, they are always equipped with rollers 20. Figures 16 and 17 show the positioning of the thermal imaging cameras 52 used to detect the motion of the water during the washing and cleaning operations, which detect the different temperature of the water introduced by special openings, not depicted, in the vicinity of the washing and cleaning equipment, which is some degrees higher than the temperature of the surrounding water, so that the motion of the water and the collection capacity of the extraction openings 49 present in the vicinity and within the washing unit itself can be seen. The extraction openings 49, and the aforementioned openings for introducing water at a higher or much higher temperature than that of the surrounding water, have an advantageous shape and are associated with the movement of vertical 38 and horizontal 39 moving elements that support the rotary brushes 36. Although not shown in Figure 18, these thermal imaging cameras are also advantageously used in conjunction with the belts with multiple jets 37, from which the jets of water can be specifically heated prior to being emitted. Moreover, the jets of slightly warmer water are advantageously used at the specific points of the hull’s surface that require a more aggressive degreasing action in order to be cleaned. The warmer water, including the hot water used to cool the thermal engines, is used to carry out washing operations, as it is more effective at eliminating the greases or oils adhering to the hull of the ship undergoing treatment, which are often present in port areas, as well as for removing particularly resistant encrustations of marine vegetation at specific points of the hull undergoing treatment. In fact, the necessary hot water is taken from the cooling circuits of the thermal motors present on the washing plant 1 or 31 used to generate the mechanical and/or electrical energy for moving the plant’s parts, for manoeuvring the plant if of the floating and manoeuvrable type 31 , and for operating the various pumps used to control the plant’s floatation and to transfer the dirty water collected in order to filter out the dirt or“fouling”. The openings used to generate the jets of warmer water cannot be used continuously, but only at times or at positions on the hull where more aggressive cleaning and washing action is required for degreasing purposes or to remove any particularly resistant encrustations of marine vegetation.

Figures 19 to 23 show the technical elements used to move the flexible bulkheads 16, especially 42, for which an inflatable edge 28 allows the bulkhead to be manoeuvred within the washing unit, as shown in the Figures. As described above, between the short walls 33 of a floating and manoeuvrable plant 31 there are at least two bulkheads 42 that delimit the section of hull 3 undergoing the washing and cleaning operations. The Figures show the size limits of the hull 3, with the minimum size shown in Figure 19 and the maximum size shown in Figure 20, and the adaptation of the flexible bulkhead 42, which is equipped with an inflatable edge 28 for support and manoeuvring purposes. The inflatable edge 28 is supported by shaped rollers 29, which, in turn, are supported by telescopic arms 53 protruding from each short wall 33 within the washing unit 41 , with the end of the arm 54 supporting the inflatable edge 28 and the flexible bulkhead 42 connected to and supported by it; each telescopic arm is thus supported by an arm slide 55 affixed to the short wall 33. A bulkhead manoeuvring mechanism 56 provides traction for the inflatable edge 28, as shown in the figures, in order to regulate the banding height of the flexible bulkhead 42 in relation to the specific size of the hull 3 engaged, with the minimum shown in Figure 19 and the maximum shown in Figure 20. When the inflatable edge 28 is released for the maximum hull size, the flexible bulkhead 42 extends along the same inflatable edge by sliding on the slide connection 57 between the flexible bulkhead 42 and the inflatable edge 28, thus extending the flexible bulkhead 42 while maintaining contact between the short wall 33 and the end of the flexible bulkhead 58 in contact with the same inside the washing unit 41. In the case of a minimum size hull 3, shown in Figure 19, the manoeuvring mechanism collects the inflatable edge 28 within a specific compartment in the short wall 33, forcing the outermost part of the flexible bulkhead 42 to slide into its connection 57 on the inflatable edge 28 and to collect the flexible bulkhead next to it 59, which, in sliding onto the connection 57, gathers against the inner wall of the washing unit 41 of the short wall 33; the flexible bulkhead’s 42 sliding connection 57 to the inflatable edge 28 must be only be duplicated at the end of the inflatable edge 28 intended to be collected in the foreseen manoeuvre compartment. Therefore, when the engaged hull is of the maximum size, as shown in Figure 20, the end of the telescopic arm 54 is retracted within the telescopic arm 53 itself.

Furthermore, Figure 21 shows a transverse cross section of the treatment of a hull at the bow, while Figure 23 shows the same treatment from the side, in which the concave shape 60 of the bow near the bulb 61 of the hull is blocked by a short inflatable wall 62 protruding outside the inflatable edge 28 in order to minimize the re-entry of water during the treatment being carried out near the concavity of the hull 3 at the bow. The short inflatable wall 62 can also be used on the tapered shape of the hull at the stern in order to limit the water that tends to re-enter between the flexible bulkheads when the washing unit is positioned near the stern of ship 2. Figure 22 shows the rotating support pins 63 of the shaped rollers 29 forming the support and manoeuvring end 64 of the inflatable edge 28 and the bulkhead 42 connected to it; in this figure and the next the inflatable edge 28 is also equipped with an element 65 for making contact with and sliding against the hull, and against the appendages 66 of the hull that serve to maintain stability during navigation.

The realisation of a flexible and inflatable bulkhead 16 in the inflatable edge 28 is depicted in Figures 24-25, in which it is applied to a washing unit 4 and in which the inflatable edge 28 is equipped with rollers 67 for sliding against the hull 3, when engaged, in order to allow the inflatable edge 28 itself to slide while in contact with the hull 3; an external blocker 48 is also visible, which can be manually moved over the above-water ends of an extraction pipe 45 connected to the bulkhead, or rather to its inflatable edge 28.

Figures 28 and 29 show the support and manoeuvring ends 64 of an inflatable tube 28 and a flexible bulkhead 42 upon which blockers for a water extraction pipe 45 have been realised in the form of both an external blocker 68 and an adjustable internal blocker 69. The end structure of the support arm is shaped 70 to accommodate the water extraction pipe. The external blocker 68 fixed to the shaped end of the arm 70 is able to be moved with the shaped rollers 29 during the positioning of the inflatable edge 28, to which the extraction pipe 45 is secured via connections 71 to the end of the shaped arm 70; the external blocker 68 thus moves together with the shaped rollers 29 supporting the inflatable edge 28, which are positioned at the level of the water L inside the washing unit.

On another design variant for double flexible bulkheads 72 on a ship hull washing and cleaning plant that can be used for the construction of large plants, Figures 30-33 show the designs of these double mounted 72 flexible bulkheads 42, or rather mounted and moved in pairs in place of a single bulkhead 42 or 16 of the previous designs. These double bulkheads are supported by an inflatable edge 73 for each bulkhead spaced away from the inflatable edge coupled and with rigid spacers 74; the end of the inflatable double edge support arm 77 supports the double edge and the double bulkheads 72 with a pair of shaped rollers 29 located outside the pair of inflatable edges 73. On this design variant, the extraction of the dirty wash water takes place both inside the washing unit C and between the pair of bulkheads D, resulting in a slight decrease in the water level LB inside the washing unit, as previously described, as well as a more slight decrease LM between the two bulkheads 72

Figures 31 and 33 show sliding rollers 67 on inflatable edges 73 similar to the inflatable edge 28, which can also be fitted with contact and sliding elements 65. Finally, the adjustable internal blocker 69 is made with a pipe with an inner casing that has an external diameter slightly smaller than the inner diameter of the extraction pipe 45; the inner diameter of the blocker tube is adequately sized to allow for the water coming from the extraction pipe 45 to be extracted. The inner blocker can be manoeuvred and moved inside the extraction pipe 45 when regulating the bulkheads of the washing unit upon which it is mounted. In fact, the inner blocker tube is moved with its lower end 75 below level L or even level LM of the water inside the washing unit. Once the end 75 has been positioned, the blocker tube is inflated inside the casing, advantageously with pressurised water, so that its outer diameter makes presses against the inner diameter of the water extraction pipe 45, thus blocking the holes 46 that would remain above the water or too close to the LB or LM water levels and ensuring the proper collection of the wash water generated during the treatment of the hull 3 between the flexible and inflatable bulkheads, as previously mentioned. The internal blocker can be repositioned by depressurising the casing and manoeuvring the blocker tube itself from the end of the water extraction pipe 45, which remains near the end 76 of the inflatable edge 73 or 28.

Whether they’re of a semi-floating and guided open basin type 1 associated with docks or piers or a floating and manoeuvrable type 31 to be used in harbours or large port areas, the functionality of these ship hull washing and cleaning plants has been broadly described and illustrated in patent applications PCT/IB2018/050870 and PCT/IT2018/050059, whose descriptions are included herein for explanatory purposes, in order to provide for a better understanding of these plants’ functionality. Moreover, the specific parts described above: parts for engaging and positioning the plant on the hull of the ship undergoing treatment; parts for handling and positioning the specific cleaning equipment within the washing units; equipment for collecting and extracting the dirty water generated during the washing process from the washing unit, the washing equipment or near the flexible bulkheads; equipment for monitoring the motion of the water during the washing process; flexible bulkheads with inflatable edges for delimiting the section of water in which the plant’s washing unit carries out the hull treatment; and even the equipment used to manoeuvre and adjust the positioning of these flexible bulkheads and their associated inflatable edges; although they refer to a specific type of plant, they can be applied to the other type of plant mentioned above with the appropriate sizing. In fact. The mass of flexible bulkheads 16 or 42 is supported in floatation by inflatable edge 28 or 73. When the washing unit detaches in order to move from one position to the next position to be cleaned on the hull 3, the inflatable edges 28 or 73 can be partially deflated, starting at the ends 76 of the inflatable edges themselves, thus allowing the inflatable edge to detach from the hull more rapidly; furthermore, if the mass of the flexible bulkhead 16 or 42 is not sufficient, e.g. in the central part of the hull shown in Figure 20, ballast weights can be applied between the inflatable edge and the flexible bulkhead in order to facilitate the detachment of the inflatable edge and to ensure a more rapid transition of the washing unit from one position to the next on the hull 3. Once the inflatable edge 28 or 73 has been deflated, the flexible bulkhead 42 or the pair 72 of flexible bulkheads associated with it can still be manoeuvred because the pair of shaped rollers 29 at the ends of the arm 54, 70 and 77 adequately supports the inflatable edge even when it’s not completely inflated, or rather less mobile in order to support the flexible bulkhead attached to it.

The functionality of the equipment for engaging the hull 3 of a ship 2 to be subjected to a washing and cleaning treatment, as described above, must be specified, above all with regard to the regulation of the mechanical spacers 17 or the adjustable mechanical spacers 51. In fact, the computerised management of the plants 1 , 31 allows for the registration of the hull type of a ship 2 that has been or is going to be engaged for treatment, thus allowing the plant to adjust its buoyancy, the positioning of the mechanical spacers 17, and the distance of the adjustable mechanical spacers 51 from the hull line X prior to engagement; the lateral pushers 19, 21 are also regulated by the computerised management system based on the size of the hull 3 to be engaged; this allows the engagement to take place under conditions of complete safety.

Moreover, the association of the equipment used to move and position the cleaning elements 14, 35 on the washing unit 4 or 41 with the dirty water extraction openings 49 allows the water to be promptly extracted immediately once the dirt or“fouling” is removed from the hull undergoing treatment, thus preventing it from drifting away within the water enclosed by the flexible bulkheads 16 or 42 that delimit the washing unit. In addition to having a pressurised water supply to activate the jets, the belts with multiple jets 37 are also associated with extraction openings (not shown), which are located next to each of the jets on the belt 37. Therefore, if the belts with multiple jets 37 are used in conjunction with the thermal imaging cameras 52, it becomes easier to see/monitor the movement of the water in contact with the hull 3, since the water sprayed by the jets can be set to a higher temperature than the water in contact with the hull undergoing treatment.

Furthermore, the functionality of the flexible bulkheads 16 and 42 equipped with inflatable edges 28 or 73, whether single or double 72, allows for the extraction of large amounts of dirty water generated due to the detachment of dirt or “fouling” from the hull, while the effect of the concentrated extraction between the bulkheads also helps prevent dispersion outside the section of hull 3 undergoing treatment at the specific point where the washing unit 4 or 41 is positioned; in fact, the slight difference in the water level LB or LM compared to the outside water level L provides for the constant entry of water from outside the washing unit, thus preventing the loss of any dirty water. In fact, this slight difference in water level is indicative of the water’s inward movement from outside the flexible bulkheads 16 or 42, which, not being watertight, allow the external water to flow into the water in the area around the hull section being treated by the washing unit 4 or 41 , thus preventing the dirt or“fouling” generated from leaving the water in the area where the washing unit is operating. That is to say that the majority of the detached dirt or “fouling” is collected by the numerous water extraction openings arranged at various points around the washing unit 4 or 41 , thus ensuring the best possible controlled disposal of the dirt or“fouling” itself, thus preventing it from being dispersed into the marine environment.

The advantages of applying the design variants of the ship hull washing and cleaning plants equipped with improved washing units, as described above, can be summarised in the more secure engagement of the ship 2 whose hull 3 is to be treated in the washing and cleaning plant 1 or 31. Furthermore, both the arrangement of extraction openings in the vicinity of the points where the dirt or “fouling” is generated (i.e. detachment from the hull), and the possibility of seeing the motion of the washing and cleaning water in contact with the hull 3 using thermal imaging cameras 52, renders the washing and cleaning operations safer and more effective, while at the same time preventing the pollution of the marine environment.

Another advantage is the possibility of having maximum certainty with regard to the extraction of the dirt or“fouling”, allowing it to be extracted with the absolute certainty that the dirty water will not be dispersed outside the washing unit 4 or 41 thanks to the use of flexible bulkheads 16 or 42 and special means of supporting and handling the same, even with inflatable edges 28 or 73.

A person skilled in the art will naturally be able to make numerous changes to a ship hull washing and cleaning plant equipped with an improved washing unit, as described above, in order to meet specific and contingent requirements, all of which are contained within the scope of protection surrounding this invention, as defined by the following claims.