JP5173995B2 - How to prevent marine organisms from sticking to marine propellers - Google Patents

Description

  The present invention relates to a method for preventing marine organism adhesion to a marine propeller.

  Large ships are outfitted in a state of floating on the sea after the hull is assembled at the construction dock. During the outfitting period, sea creatures such as barnacles and mussels attach to the ship's propellers. In order to reduce the efficiency of the propeller, the attached marine life is cleaned by removing the propeller before commissioning of the ship (sea trial). If the final dock is not performed, the cost will be incurred because the diver cleans the propeller at the end of the outfitting period. Furthermore, during the cleaning by the diver, it is necessary to stop the seawater pump of the ship and stop the equipment adjustment operation of the engine room in order to ensure safety, so the outfitting period becomes longer. When the trial run is over and the ship is delivered to the shipowner and starts operation, the propeller will not stop for a long time. Therefore, it is difficult for marine organisms to adhere to the propeller after the start of operation.

  Patent Document 1 discloses a propeller cover that prevents a shell such as a barnacle from adhering to a propeller of a small ship when a small ship such as a cruiser is moored on the sea in a seawater region. The propeller cover is made of plastic and prevents the attachment of shellfish by blocking the flow of seawater.

  Patent Document 2 discloses a method for preventing the adhesion and propagation of marine organisms by providing a propeller with a marine organism preventing paint or marine organism preventing polymer, and a substance that gradually dissolves from the marine organism preventing paint or marine organism preventing polymer in seawater. doing.

JP 9-249193 A Japanese Utility Model Publication No. 62-6097

  An object of the present invention is to provide a method for preventing adhesion of marine organisms to a marine propeller and a marine organism adhesion preventing bag in which the cost for propeller cleaning is reduced.

  The means for solving the problem will be described below using the numbers used in the (DETAILED DESCRIPTION). These numbers are added to clarify the correspondence between the description of (Claims) and (Mode for Carrying Out the Invention). However, these numbers should not be used to interpret the technical scope of the invention described in (Claims).

  The marine organism adhesion prevention method to the marine propeller according to the present invention includes a step (S21, S41) of covering the propeller (20) with nets (32, 40) and a step of removing the net from the propellers (S22, S42). It has.

  In the step of covering with the net, the entire propeller is covered with the net.

  In the step of covering with the net, the net is suspended from the hull with a rope (35).

  The step of covering with the net includes the step of covering the plurality of blades (22) of the propeller with a plurality of bags (40), respectively. The plurality of bags are formed of the net.

  The step of covering each of the plurality of blades with the plurality of bags includes covering the first bag (40) of the plurality of bags with the first blade (22) of the plurality of blades; A step of closing a gap between the mouth (43) of one bag and the first blade with a waterproof tape (50).

  A rope band (46) is provided on the first bag. In the step of covering the first bag, the rope attached to the rope band is operated to cover the first bag over the first blade.

  The marine organism adhesion preventing method according to the present invention includes a step (S11, S31, S41) of covering the propeller (20) with a sheet (31, 40) that does not allow seawater to pass, and a step of removing the sheet from the propeller ( S12, S33, S42).

  In the step of covering with the sheet, the entire propeller is covered with the sheet. The marine organism adhesion preventing method on the marine propeller further includes a step (S32) of blowing gas into the seawater in the seat.

  The gas is carbon dioxide.

  The marine organism adhesion prevention bag (40) for covering the blades of the marine propeller according to the present invention includes a bag body (41, 42) formed of a net or a sheet that does not allow seawater to pass through.

  The marine organism adhesion prevention bag further includes a rope band (46) provided on the bag body.

  The bag body is formed of the net. The mesh size of the net is 200 μm or less.

  ADVANTAGE OF THE INVENTION According to this invention, the marine organism adhesion prevention method and marine organism adhesion prevention bag to the ship propeller which the cost for propeller cleaning is reduced are provided.

FIG. 1 is a flowchart of a method for preventing marine organism adhesion to a marine propeller according to a first embodiment of the present invention. FIG. 2 is a side view of the hull to which the marine organism adhesion preventing method to the marine propeller according to the first embodiment is applied. FIG. 3 is a flowchart of a method for preventing marine organism adhesion to a marine propeller according to a second embodiment of the present invention. FIG. 4 is a side view of a hull to which a marine organism adhesion preventing method for a marine propeller according to a second embodiment is applied. FIG. 5 is a flowchart of a method for preventing marine organism adhesion to a marine propeller according to a third embodiment of the present invention. FIG. 6 is a side view of a hull to which a marine organism adhesion preventing method for a marine propeller according to a third embodiment is applied. FIG. 7 is a flowchart of a method for preventing marine organism adhesion to a marine propeller according to a fourth embodiment of the present invention. FIG. 8 shows a bag used in the method for preventing marine organism adhesion to a marine propeller according to the fourth embodiment. FIG. 9 shows a propeller to which a marine organism adhesion preventing method for a marine propeller according to a fourth embodiment is applied.

  With reference to an accompanying drawing, the form for carrying out the marine organism adhesion prevention method and the marine organism adhesion prevention bag by the present invention is explained below.

(First embodiment)
With reference to FIG. 1, the marine organism adhesion prevention method to the ship propeller which concerns on the 1st Embodiment of this invention is equipped with step S11 which covers the whole propeller with a sheet | seat, and step S12 which removes a sheet | seat.

  With reference to FIG. 2, step S11 which covers the whole propeller with a sheet | seat is demonstrated. FIG. 2 shows the hull 10 moored on the outfitted quay after being assembled at the construction dock. A propeller 20 for propulsion is provided at the stern portion of the hull 10. The propeller 20 is coupled to a shaft 15 protruding from the hull 10. The propeller 20 includes a boss 21 and a plurality of blades 22. Step S11 for covering the entire propeller with the sheet is performed in a state where the hull 10 is floated on water. In step S11 of covering the entire propeller with a sheet, the entire propeller 20 including the boss 21 and the plurality of blades 22 is covered with a sheet 31 such as a vinyl sheet that does not allow seawater to pass through. Here, the diver guides the sheet 31 so as to cover the propeller 20, and the gap between the sheet 31 and a part of the hull 10 (for example, bossing) is closed with the waterproof tape 50. The seat 31 is hung from the hull 10 by a rope 35 so that the land worker can remove the seat 31.

  Since the seawater around the propeller 20 is prevented from being exchanged by the seat 31, marine organisms such as barnacles and mussels are prevented from attaching to the surface of the propeller 20 during the outfitting period of the hull 10.

  Step S12 is performed to remove the seat at the end of the outfitting period (before the trial run). In step S <b> 12 for removing the sheet, the sheet 31 is removed from the propeller 20. Specifically, the diver peels off the waterproof tape 50, and the land worker pulls the rope 35 to remove the seat 31 from the propeller 20. Here, when marine life is attached to the sheet 31, the marine life is removed together with the sheet 31.

  The working time of the diver in the present embodiment is shorter than the working time when the diver removes marine life attached to the propeller as in the prior art.

  According to the marine organism adhesion preventing method for the marine propeller according to the present embodiment, the cost for cleaning the propeller can be reduced. Furthermore, since the working time by the diver is short, it takes only a short time to stop the seawater pump or stop the equipment adjustment operation in the engine room to ensure safety, thereby shortening the outfitting period.

  The marine organism adhesion prevention method according to the present embodiment prevents marine organisms from adhering by covering the propeller 20 with a flexible sheet 31, and therefore, compared with a method of covering the propeller with a hard propeller cover made of plastic. It is suitable for preventing marine organisms from adhering to the propellers of large ships.

  In the present embodiment, the gap between the seat 31 and the shaft 15 may be closed with the waterproof tape 50 instead of closing the gap between the seat 31 and a part of the hull 10 (for example, bossing) with the waterproof tape 50. .

(Second Embodiment)
Referring to FIG. 3, the marine organism adhesion preventing method for a marine propeller according to the second embodiment of the present invention includes step S21 for covering the entire propeller with a net and step S22 for removing the net.

  With reference to FIG. 4, step S21 which covers the whole propeller with a net | network is demonstrated. Step S21 for covering the entire propeller with the net is performed in a state where the hull 10 is floated on water. In step S21 of covering the entire propeller with a net, the entire propeller 20 is covered with a net 32 having a fine mesh used for a plankton net. Here, since the size of the larvae of barnacles and mussels is 200 μm or more, the mesh size (opening) of the net 32 is preferably 200 μm or less. Here, the diver guides the net 32 so as to cover the propeller 20, and the gap between the net 32 and a part of the hull 10 (for example, bossing) is closed with the waterproof tape 50. The net 32 is suspended from the hull 10 with a rope 35 so that the land worker can remove the net 32.

  Since the propeller 20 is covered with the net 32, marine organisms such as barnacles and mussels are prevented from adhering to the surface of the propeller 20 during the outfitting period of the hull 10.

  Step S22 for removing the net is executed at the end of the outfitting period (before the trial run). In step S22 for removing the net, the net 22 is removed from the propeller 20. Specifically, the diver peels off the waterproof tape 50, and the land worker pulls the rope 35 to remove the seat 31 from the propeller 20. The work time for the diver to peel off the waterproof tape 50 is shorter than the work time when the diver removes marine life attached to the propeller as in the prior art. Here, when marine life is attached to the net 32, the marine life is removed together with the net 32.

  The working time of the diver in the present embodiment is shorter than the working time when the diver removes marine life attached to the propeller as in the prior art.

  According to the marine organism adhesion prevention method to the marine propeller according to the present embodiment, the same effect as the marine organism adhesion prevention method to the marine propeller according to the first embodiment is provided. Further, according to the marine organism adhesion preventing method for the marine propeller according to the present embodiment, since the seawater can pass through the net 32, the net 32 can be prevented from greatly shaking due to the water flow. Furthermore, according to the marine organism adhesion preventing method to the marine propeller according to the present embodiment, since air can pass through the net 32, there is no problem of air bleeding for preventing buoyancy.

  In the present embodiment, the gap between the net 32 and the shaft 15 may be closed with the waterproof tape 50 instead of closing the gap between the net 32 and a part of the hull 10 (for example, bossing) with the waterproof tape 50.

(Third embodiment)
Referring to FIG. 5, the marine organism adhesion preventing method for a marine propeller according to the third embodiment of the present invention includes step S31 for covering the entire propeller with a sheet, step S32 for blowing gas into the sheet, and the sheet. A removal step S33 is provided.

  Step S31 for covering the entire propeller with the sheet and step S33 for removing the sheet are the same as step S11 for covering the entire propeller with the sheet and step S12 for removing the sheet. Step S32 for blowing gas into the sheet is executed between step S31 for covering the entire propeller with the sheet and step S33 for removing the sheet.

  With reference to FIG. 6, step S32 which blows gas in a sheet | seat is demonstrated. In step S32 for blowing gas into the sheet, carbon dioxide gas is blown into the seawater in the sheet 31 through the gas supply path 38 so that the seawater in the sheet 31 has a predetermined pH or lower. By reducing the pH of the seawater in the sheet 31, it is possible to reliably prevent marine life from adhering to the surface of the propeller 20. Here, the predetermined pH is 6.5 or less. Step S32 for blowing gas into the sheet may be performed periodically, or may be performed when the pH of the seawater in the sheet 31 becomes higher than a predetermined pH.

  In step S <b> 32 in which gas is blown into the sheet, a gas other than carbon dioxide gas that has an effect of preventing marine life from adhering to the surface of the propeller 20 may be blown into the seawater in the sheet 31.

(Fourth embodiment)
Referring to FIG. 7, the marine organism adhesion preventing method for a marine propeller according to the fourth embodiment of the present invention polishes the propeller boss, step S41 for covering the propeller blade with a bag, step S42 for removing the bag, and the like. Step S43 is provided.

  FIG. 8 shows a marine organism adhesion prevention bag 40 used in the marine organism adhesion prevention method according to the present embodiment. The bag 40 is formed of a fine mesh such as that used for a plankton net. Here, since the size of larvae of barnacles and mussels is 200 μm or more, the size of the net (mesh) is preferably 200 μm or less.

  The bag 40 includes a front side net 41 and a back side net 42 disposed on the opposite side of the front side net 41. The front side net 41 and the back side net 42 are closed at the side edge 44 and the bottom edge 45 of the bag 40 to form the main body portion of the bag 40. The front side net 41 and the back side net 42 are not closed at the opening edge 43 of the bag 40. The opening edge 43 is disposed around the opening of the bag 40. A plurality of eyelets 47 are arranged along each of the opening edge 43 and the side edge 44. The eyelet 47 increases the strength of the bag 40. A rope band 46 is provided on each of the front side net 41 and the back side net 42. The rope band 46 includes two end portions 46 a coupled to the front side net 41 or the back side net 42, and an intermediate portion 46 b disposed between the two end portions 46 a and not coupled to the front side net 41 or the back side net 42.

  With reference to FIG. 9, step S41 which covers a propeller blade | wing with a bag is demonstrated. The step S41 of covering the propeller blades with the bag is performed (in the air) at the building dock before the hull 10 assembled at the building dock is floated on water.

  In step S41 of covering the propeller blades with the bags, the plurality of blades 22 of the propeller 20 are covered with the plurality of bags 40, respectively. More specifically, the bag 40 is covered with the blade 22, and the gap between the mouth (opening edge 43) of the bag 40 and the base portion of the blade 22 is closed with the waterproof tape 50. Here, if a rope (not shown) is attached to the rope band 46 and the bag 40 is covered with the blades 22 by operating the rope, the operation is easy. Further, when a string (not shown) is passed through a plurality of eyelets 44 arranged on the opening edge 43 and the opening of the bag 40 is squeezed with the string, the opening edge 43 is brought into close contact with the root portion of the blade 22. The work of closing the gap between the mouth (opening edge 43) and the base portion of the blade 22 with the waterproof tape 50 is facilitated.

  After step S41 for covering the propeller blades with the bag, the hull 10 is floated on the water, and the hull 10 is outfitted at the outfitting quay. During the outfitting period, the bag 40 prevents sea creatures such as barnacles and mussels from adhering to the surface of the blade 22.

  At the end of the outfitting period (before the trial run), step S42 for removing the bag and step S43 for polishing the propeller boss are executed. In step S <b> 42 for removing the bag, the diver removes the bag 40 from the blade 22. Here, when marine life is attached to the bag 40, the marine life is removed together with the bag 40. In step S43 for polishing the propeller boss, the diver polishes the boss 21 to remove marine organisms attached to the surface of the boss 21. The working time of the diver in this embodiment is shorter than the working time when the diver polishes the entire propeller as in the prior art.

  According to the marine organism adhesion prevention method to the marine propeller according to the present embodiment, the same effect as the marine organism adhesion prevention method to the marine propeller according to the first embodiment is provided. Furthermore, according to this embodiment, since each blade 22 is covered with the bag 40, the work is easier than when the entire propeller 20 is covered with a net. Further, since the bag 40 is formed of a net, it is not necessary to remove air from the bag 40 in order not to generate buoyancy, and the working time is shortened.

  In addition, in this embodiment, you may form the main-body part of the bag 40 with the sheet | seat which does not let seawater like a vinyl sheet. In the present embodiment, step S41 of covering the propeller blades with the bag may be performed in a state where the hull 10 is floated on the water.

DESCRIPTION OF SYMBOLS 10 ... Hull 15 ... Shaft 20 ... Propeller 21 ... Boss 22 ... Blade 31 ... Sheet 32 ... Net 35 ... Rope 38 ... Gas supply path 40 ... Sea life adhesion prevention bag 41 ... Front side net 42 ... Back side net 43 ... Opening edge 44 ... side part edge 45 ... bottom part edge 46 ... rope band 46a ... end part 46b ... intermediate part 47 ... eyelet 50 ... waterproof tape

Claims (4)

Covering the propeller with the net,
Removing the net from the propeller ,
The step of covering with the net includes the step of covering the plurality of blades of the propeller with a plurality of bags, respectively.
The plurality of bags are formed of the net;
The step of covering the plurality of blades with the plurality of bags, respectively,
Placing the first bag of the plurality of bags on the first blade of the plurality of blades;
Sealing a gap between the mouth of the first bag and the first blade with a waterproof tape;
For preventing marine organisms from adhering to marine propellers. The method of preventing marine life adhesion to a marine propeller according to claim 1, wherein in the step of covering with the net, the entire propeller is covered with the net. The method of preventing marine organism adhesion to a marine propeller according to claim 2, wherein in the step of covering with the net, the net is suspended from the hull with a rope.   A rope band is provided on the first bag;
  In the step of covering the first bag, the rope attached to the rope band is operated to cover the first bag on the first blade.
  A method for preventing adhesion of marine organisms to the marine propeller according to claim 1.

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