JP3018755B2 - Electrocoat rust prevention equipment for ballast tanks on ships - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrocoating rust preventive device used for preventing rust in a ballast tank of a ship.

[0002]

2. Description of the Related Art Heretofore, as one of the rust preventive measures which can be substituted for the painting of a structure, a rust preventive device by an electrocoating method has been employed.

[0003] In this conventional electrocoating rust prevention device, a cathode is arranged on a structure, and an anode is arranged in seawater.
Both poles are connected to a power supply to allow current to flow, and seawater is electrolyzed to cause dissolved metal ions in the seawater to adhere to the surface of the structure facing the seawater, forming a film and preventing rust. And was partially adopted in marine structures such as bridges.

[0004]

However, in the above-mentioned conventional electro-coating rust preventive device, since the object is a simple structure, it is not necessary to consider the current distribution so much. However, it was not used as an auxiliary means of rust prevention measures, and was not intentionally intended in advance for the formed film components, film thickness, and the like. In addition, conventional rust preventive devices based on the electrocoating method simply place an anode in seawater and generate a film by electrochemical change, and as a single rust preventive measure for large structures such as ship ballast tanks. When considered, a large current is required to maintain the effectiveness of the formed film, and a large-scale power supply device is required.

Accordingly, the present invention provides a large-scale power supply device by increasing the electrolytic efficiency of film formation during rust prevention in a ballast tank of a ship to actively generate the film and reduce the amount of current. The aim is to provide an electrocoating rust preventive device that is not required.

[0006]

According to the present invention, in order to solve the above-mentioned problems, an anode is disposed in seawater in a ballast tank, and a cathode is disposed in the ballast tank, and both poles are connected to a power supply device. Further, at the inlet side of the ballast tank in the middle of the line for supplying seawater to the ballast tank, an additive injection device for uniformly mixing at least sodium carbonate or sodium hydrogen carbonate and sodium hydroxide or potassium hydroxide at least. Are connected.

Further, a mixture of thiourea and gelatin may be used as an additive.

[0008]

[Action] By using an additive that increases the electrolysis efficiency in the ballast tank by injecting the additive into the ballast pump inlet side, the additive can be uniformly mixed into the seawater in the ballast tank. The agent can reduce the current density required for forming a film, and can greatly reduce the facilities of a power supply device. Furthermore, thiourea,
By mixing gelatin, the denseness of the formed film can be improved and the current distribution in the ballast tank can be made uniform.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 (a) and (b) show one embodiment of the present invention, in which an additive 1 or a mixture of sodium carbonate or sodium bicarbonate and sodium hydroxide or potassium hydroxide are uniformly mixed. A mixture of thiourea and gelatin adjusted at a certain mixing ratio is used as an additive 1, and an additive injection device 2 containing the additive 1 is installed in an engine room 14 of a ship 3. The additive injection pipe 4 from the injection device 2 is connected to the inlet side of a ballast pump 7 provided in the middle of a pipe 9 for filling the seawater 5 from the seawater inlet 8 into the ballast tank 6. By storing the additive 1 into the pipe 9 from the additive introduction pipe 4, the seawater 5 in the pipe 9 and the additive 1 are mixed and supplied to the ballast tank 6 by the ballast pump 7. I do. Further, an anode 11 is disposed in the seawater 10 in the ballast tank 6, and a cathode 12 is disposed on the wall of the ballast tank 6. The anode 11 and the cathode 12 are connected to a power supply device 13, A current is supplied from the supply device 13 between the anode 11 and the cathode 12 to electrolyze the seawater 10 in the ballast tank 6, thereby electrically depositing dissolved metal ions in the seawater 10. Ensure that a rust-proof coating is formed. Ballast tank 6
When the seawater is filled, the additive 1 is added to the seawater 10 in the ballast tank 6 by mixing the additive 1 into the seawater in the pipe 9 from the additive injection device 2, and then the seawater 10 is supplied from the power supply device 13. When a current is caused to flow through the tank, dissolved metal ions in the seawater 10 in the ballast tank 6 are electrically deposited on the tank surface to form a film. The effect of the additive 1 improves the rust prevention effect of the film.

In the above, sodium carbonate or sodium bicarbonate used as the additive 1 has an effect of increasing calcium ions in the electrocoating, improves the rust-preventing effect of the film, and prolongs the life of the film. And the required current density for film formation can be reduced, and sodium hydroxide or potassium hydroxide can also be used in the same manner as the above-mentioned sodium carbonate or sodium hydrogen carbonate. Can be reduced. Therefore, by using an additive obtained by uniformly mixing the above-mentioned sodium carbonate or sodium hydrogen carbonate with sodium hydroxide or potassium hydroxide, it is possible to increase the electrolysis efficiency for film formation, reduce the amount of current, and supply power. Can be reduced. Furthermore,
By adding thiourea, it is possible to improve the denseness of the resulting film and to produce a film with high corrosion resistance. It is possible to maintain the uniformity of the current distribution even in a region where the current is difficult to reach, such as a region farther than the anode and a region farther than the anode, and the effect of forming a film can be enhanced.

In the above embodiment, the additive 1
Although a mixture of sodium carbonate or sodium hydrogen carbonate and sodium hydroxide or potassium hydroxide, or a mixture of these with thiourea or gelatin is shown,
Of course, it is possible to use these mixing ratios by variously changing them, and it is needless to say that various changes can be made without departing from the gist of the present invention.

[0013]

As described above, according to the electrocoating rust preventive apparatus for a ballast tank in a ship according to the present invention, sodium carbonate or sodium hydrogen carbonate and sodium hydroxide or potassium hydroxide are uniformly mixed as additives. Or a mixture of thiourea and gelatin adjusted at a certain mixing ratio, and a pipe connecting the additive from the additive injection device storing the additive to the seawater intake port of the ship and the ballast pump The ballast tank is connected to the inlet side of the ballast tank so that the additive can be mixed into the seawater in the ballast tank, so that the additive can be uniformly mixed into the ballast tank. Improve the electrolysis efficiency at the time of film formation, improve the denseness of the film, and promote the longevity of the film,
It is possible to generate a film having high corrosion resistance, and further, since the amount of current can be reduced by increasing the electrolytic efficiency, it is possible to reduce the equipment of the power supply device and reduce the equipment cost. And so on.

[Brief description of the drawings]

FIG. 1 shows an embodiment of an electro-coating rust preventive device of the present invention, in which (a) is a side view showing an outline,
FIG. 2B is a partially enlarged view taken along the line AA of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Additive 2 Additive injection apparatus 3 Ship 4 Additive injection pipe 7 Ballast pump 8 Seawater intake 9 Pipe (line) 10 Seawater 11 Anode 12 Cathode 13 Power supply device

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kenichi Akamine 3-1-1-15 Toyosu, Koto-ku, Tokyo Ishikawajima-Harima Heavy Industries, Ltd. (72) Inventor Tomoyo Maruko 3-1-1 Toyosu, Koto-ku, Tokyo No. 15 Ishikawa Shima Harima Heavy Industries, Ltd.Technical Research Institute (72) Inventor Yoichi Hirai 3-1-1 Toyosu, Koto-ku, Tokyo Inside Ishikawa Shima Harima Heavy Industries Co., Ltd.Technical Research Laboratory (72) Inventor Teruaki Kawamoto No. 3-Chome 1-115 Ishikawa Shima-Harima Heavy Industries, Ltd. (58) Investigated field (Int. Cl. ⁷ , DB name) C23F 13/00 B63B 9/00

Claims (2)

(57) [Claims] 1. An anode is arranged in seawater in a ballast tank, and a cathode is arranged in a ballast tank. Both poles are connected to a power supply device. Further, in the middle of a line for supplying seawater to the ballast tank, An electro-corrosion prevention device for a ballast tank in a ship, wherein an injection device for an additive obtained by uniformly mixing at least sodium carbonate or sodium hydrogen carbonate and sodium hydroxide or potassium hydroxide is connected. 2. The rust-prevention apparatus according to claim 1, wherein said additive further comprises a mixture of thiourea and gelatin.