JP2004052080A - Device for applying corrosion protection coating on surface of wetted part in mechanical structure made of metal installed underwater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for applying a corrosion protection coating on the surface of a wetted part in a mechanical structure made of metal installed underwater, which does not need to apply a conventional heavy coating onto a submersible pump and the like, does not adversely affect an operator and surroundings, and inexpensively applies the coating. <P>SOLUTION: This device has a variable constant voltage DC power-supply unit 4 of which the negative side output terminal 5 is connected to the mechanical structure that is made of metal, installed underwater, and immersed in an electrolytic solution 7, and of which the positive side output terminal 6 is connected to the electrostatic electrode 3 installed so as to face the structure in the electrolytic solution 7, and has such a configuration as to form an electric circuit of the variable constant voltage DC power-supply unit 4 through the electrolytic solution 7 when the voltage is applied. The electrostatic electrode connected to the positive side output terminal 5 of the above variable constant voltage DC power-supply unit 4 may be composed of an insoluble material. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to an apparatus for applying an anticorrosion coating to a surface of a wetted part of a metal mechanical structure installed and used in water, such as a submersible pump.
[0002]
[Prior art and its problems]
Conventionally, submersible pumps, etc. have been subjected to heavy corrosion protection coating on the wetted parts in order to enhance weather resistance and corrosion resistance, and the paint is composed of chemical components such as organic solvents, tar, epoxy resin, and chlorinated rubber. As a result, the environment of the painter is in a poor condition, and if these components leak from the workplace to the outside world, serious problems will occur to the ecosystem in the surrounding environment. In addition, during actual operation after installation of a submersible pump, etc., the effect on the ecosystem due to the elution of paint components into the environment due to coating deterioration is remarkable, and during maintenance after operation at the place where the submersible pump etc is realized, For re-painting, the existing paint film is peeled off with a hand tool or blast, etc., but the treatment of these debris is disposed of in large quantities as industrial waste. It requires expensive facilities, and in the case of landfill disposal, disposal at a special landfill facility is required so as not to affect geology or groundwater. In this way, the coating containing chemical components on the submersible pump has a remarkably large environmental load at any stage of construction, maintenance, and disposal, and requires a great deal of labor and cost to handle. ing.
[0003]
At present, environmentally friendly paints with a reduced content of organic solvents have become mainstream. However, since the workability is poor and the coating is difficult, the coating time is actually long, and the operator is forced to work for a long time in a poor environment. In addition, the air vent hole provided in the casing may be closed by painting, causing an air lock and making it impossible to pump water.In such a case, a technician rushes to the site and sends it to the submersible pump. The current situation is that there is no other way than to stop the power supply and to raise the pump and install a new replacement machine. The drain pump equipment is usually installed as a set of two main pumps and auxiliary pumps. If any abnormality occurs in the main pump and the pump stops, the auxiliary pump starts operation immediately and continues draining However, since the phenomenon of pump abnormality due to deposition of deposits proceeds almost simultaneously in two pumps, it is conceivable that both pumps cannot be drained and the surroundings are flooded.
[0004]
[Object of the invention]
An object of the present invention is to provide a submersible pump that does not require a conventional heavy-duty anticorrosive coating on a submersible pump or the like, has excellent maintainability without adversely affecting workers and the surrounding environment, and can be implemented at low cost. It is an object of the present invention to provide an anticorrosion coating application device for a liquid contact surface of a machine-made machine structure.
[0005]
Configuration of the Invention
In the apparatus for performing anticorrosion coating on the surface of a wetted part in a metal machine structure installed underwater according to the present invention, a metal machine structure installed underwater in which the negative output terminal of a variable constant voltage DC power supply is immersed in an electrolyte solution And the positive side output terminal of the variable constant voltage DC power supply is connected to the charging electrode opposite to the electrolyte solution, and an electric circuit of the variable constant voltage DC power supply is formed through the electrolyte solution by applying a voltage. It was configured to be. Further, the charging electrode connected to the positive output terminal of the variable constant voltage DC power supply may be made of an insoluble material.
[0006]
[Action]
An electric circuit of a variable constant-voltage DC power supply device is formed through an electrolyte solution by applying voltage, the charging electrode is positively charged, and the calcium ions and magnesium ions in the electrolyte solution are negatively charged. It is attracted to the surface of the liquid contacting part of the mechanical structure, and is deposited and deposited in a layered manner as an electrodeposit made of calcium carbonate, magnesium hydroxide, or the like, and an anticorrosive film having a uniform thickness is formed.
[0007]
【Example】
Hereinafter, description will be made with reference to the case of FIG. 1 in which the submersible pump is implemented.
[0008]
Reference numeral 1 denotes an underwater-installed metal mechanical structure to which the anticorrosion coating is applied, which is installed in an electrolyte solution 7, and is a submersible pump in the example of FIG. Reference numeral 2 denotes a conductive air outlet of the underwater-installed metal mechanical structure 1, which corresponds to a discharge pipe of the submersible pump. Reference numeral 3 denotes a chargeable electrode, which may be an insoluble, for example, platinum-plated titanium electrode. Reference numeral 4 denotes a variable constant-voltage DC power supply, and its negative output terminal 5 is connected to the conductive air outlet 2 of the underwater-installed metal mechanical structure 1, and its positive output terminal 6 is connected to the charging electrode 3. You. The electrolyte solution 7 may be, for example, seawater or artificial seawater that does not adversely affect the environment. If the pump is operated in the sea, the seawater is used as the electrolyte solution 7 as it is.
[0009]
When a voltage is applied by the above-described configuration, an electric circuit of the variable constant-voltage DC power supply 4 is formed via the electrolyte solution 7, and the charging electrode 3 connected to the positive side is positively charged. Calcium ions and magnesium ions are attracted to the liquid contacting surface of the underwater-installed metal mechanical structure 1 which is negatively charged, and are deposited and deposited in layers as electrodeposits made of calcium carbonate, magnesium hydroxide, etc. A thick anticorrosive coating will be produced. The thickness of the anticorrosion coating is controlled by increasing or decreasing the magnitude or time of the applied voltage, and the ultra-fine ionized substance having a potential difference is electrodeposited as a uniform and desired thickness, for example, as an ultra-thin anticorrosion coating. Will be. Further, when the chargeable electrode 3 is made of an insoluble material, the chargeable electrode 3 itself is not eluted and consumed in the electrolyte solution 7, so that a stable electrodeposition coating process is maintained.
[0010]
【The invention's effect】
According to the present invention, an ultra-thin and uniform anti-corrosion coating is applied not only to a liquid contact surface of a submersible pump or the like but also to a fitting and a movable part which has conventionally been unable to be painted and crevice corrosion has occurred. Can be applied. In addition, since natural substances from the natural world are used without using artificial chemicals such as organic solvents and resins as in the past, excellent maintenance and low cost without adversely affecting workers and the surrounding environment. It can be implemented naturally, and it is naturally reduced at the time of disposal and is pollution-free. In addition, when the chargeable electrode is made of an insoluble material, there is an advantage that stable electrodeposition coating treatment is maintained for a long time because there is no elution and consumption of the electrode itself into the electrolyte solution.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a configuration of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Underwater metal machine structure 3 Chargeable electrode 4 Variable constant voltage DC power supply 5 Negative output terminal 6 Positive output terminal 7 Electrolyte solution

Claims (2)

The negative output terminal of the variable constant-voltage DC power supply was connected to a submerged metal mechanical structure immersed in the electrolyte solution, and the positive output terminal of the variable constant-voltage DC power supply was connected to the electrolyte solution. Connected to a charging electrode and configured to form an electric circuit of a variable constant-voltage DC power supply device through an electrolyte solution by applying a voltage, to a liquid-contacting surface of a submerged metal mechanical structure. Anticorrosion coating construction equipment. The anticorrosion coating applied to the surface of a wetted metal mechanical structure according to claim 1, wherein the charging electrode connected to the positive output terminal of the variable constant voltage DC power supply device is made of an insoluble material. apparatus.

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