Electrocoating film forming apparatus and method

Abstract

The present invention provides an electrodeposition coating forming apparatus and an electrodeposition coating forming method that can suppress the increase in workload and other factors when forming an electrodeposition coating on a material to be protected from corrosion. [Solution] The electrodeposition coating forming apparatus and electrodeposition coating forming method hold a metal member, which is less noble than the object to be protected from corrosion, in the electrolyte via a holding member, and which constitutes the counter electrode of the object to be protected from corrosion, which is at least partially immersed in the electrolyte, and electrically connect the metal member and the object to be protected from corrosion by wiring.

Description

Technical Field

[0001] The present disclosure relates to an electrodeposition film forming apparatus and an electrodeposition film forming method.

Background Art

[0002] Patent Document 1 discloses an electric corrosion prevention method using a self-boosting type galvanic anode, which comprises installing an auxiliary cathode having a nobler potential than the galvanic anode in an electrolyte environment near the galvanic anode made of zinc, aluminum, magnesium, or an alloy thereof, and supplying a corrosion prevention current to the object to be protected by an output voltage obtained by boosting or reducing the voltage generated between the two electrodes.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] According to the technique described in Patent Document 1, in order to supply a corrosion prevention current to the object to be protected, the electrical contact of the galvanic anode may be underwater welded to the object to be protected. In such a case, it is necessary to gather a large number of divers having underwater welding techniques, experience, and qualifications, and further to prepare an environment in which the work can be carried out. As a result, there is a problem that the work load and the like when forming an electrodeposition film on the object to be protected tend to increase.

[0005] The present disclosure has been made in view of the above problems. An object thereof is to provide an electrodeposition film forming apparatus and an electrodeposition film forming method capable of suppressing an increase in work load and the like when forming an electrodeposition film on an object to be protected.

Means for Solving the Problems

[0006] The electrodeposition coating apparatus and electrodeposition coating method according to this disclosure include holding a metal member, which is less noble than the object to be protected, in the electrolyte via a holding member, and constituting the counter electrode of the object to be protected, which is at least partially immersed in the electrolyte, and electrically connecting the metal member and the object to be protected by wiring.

[0007] The metal component may have a greater ionization tendency than aluminum.

[0008] The metal component may be made of magnesium or an alloy in which magnesium is the main element.

[0009] The material to be protected from corrosion may be made of iron or an alloy in which iron is the main element.

[0010] The electrical contacts between the wiring and the corrosion-protected material may be located in a part of the corrosion-protected material that is not immersed in the electrolyte.

[0011] The holding member may be one which suspends the metal member from below the holding member.

[0012] The retaining member may be one that anchors a metal member to the bottom of the electrolyte flow path.

[0013] The holding member may hold the metal member within a predetermined area spaced apart from the object to be protected from corrosion.

[0014] A battery may be constructed with the material to be protected from corrosion as the positive electrode and a metal component as the negative electrode, and an electrodeposited coating may be formed on the surface of the material to be protected from corrosion by the current flowing from the positive electrode to the negative electrode. [Effects of the Invention]

[0015] According to this disclosure, it is possible to provide an electrodeposition coating forming apparatus and an electrodeposition coating forming method that can suppress the increase in workload and other factors when forming an electrodeposition coating on a material to be protected from corrosion. [Brief explanation of the drawing]

[0016] [Figure 1] It is a schematic diagram showing the configuration of the electrodeposition film forming apparatus of the present disclosure. [Figure 2] It is a top view showing an example of the arrangement of the metal members. [Figure 3] It is a diagram showing an example of the procedure for arranging the electrodeposition film forming apparatus.

Mode for Carrying Out the Invention

[0017] Hereinafter, some exemplary embodiments will be described with reference to the drawings. In the drawings, the same reference numerals are given to the common parts, and duplicate explanations are omitted.

[0018] [Configuration of Electrodeposition Film Forming Apparatus] FIG. 1 is a schematic diagram showing the configuration of the electrodeposition film forming apparatus of the present disclosure. As shown in FIG. 1, the electrodeposition film forming apparatus 1 includes a metal member 20, a holding member 30, and a wiring 40. The electrodeposition film forming apparatus 1 is used to form an electrodeposition film on the surface of the object to be protected 10.

[0019] Here, the object to be protected 10 may be made of iron or an alloy having iron as a main element. For example, the object to be protected 10 may be a harbor steel structure such as a steel sheet pile or a steel pipe pile, a marine steel structure such as a bridge caisson, a floating structure, or a ship, or an underwater steel structure existing in a tidal zone such as a sluice. The object to be protected 10 is not limited to the examples listed here.

[0020] Note that a structure BS may be installed above the object to be protected 10. For example, the structure BS may be made of concrete.

[0021] The object to be protected 10 is at least partially immersed in the electrolyte EL. By forming an electrodeposition film on the surface of the object to be protected 10, corrosion of the object to be protected 10 itself in the electrolyte EL is suppressed. For example, the electrolyte EL may contain cations such as Ca 2+ ions or Mg 2+ ions. The electrolyte EL may be a fluid, such as seawater, brackish water, or the like.

[0022] On the surface of the corrosion-protected object 10, the Ca dissolved in the electrolyte EL 2+ Ions or Mg 2+ An electrodeposited film is formed on the surface of the object to be protected from corrosion 10 by electrolysis, which causes ions to be deposited as an electrodeposited material mainly composed of CaCO3 or Mg(OH)2. Here, in an electrolyte EL, when a battery is constructed with the object to be protected from corrosion 10 as the positive electrode and the metal member 20 (described later) as the negative electrode, the electrodeposited film is formed by the current flowing from the positive electrode to the negative electrode.

[0023] The metal component 20 constitutes the counter electrode of the material to be protected and has a less noble property than the material to be protected 10. In other words, the metal component 20 has a greater ionization tendency than the material to be protected 10. For example, the metal component 20 has a greater ionization tendency than aluminum. In order to increase the current flowing from the positive electrode to the negative electrode, the metal component 20 may be made of magnesium or an alloy in which magnesium is the main element.

[0024] Furthermore, the shape of the metal member 20 is not particularly limited, but it may be cylindrical, prismatic, or the like. A general-purpose galvanic anode can be used for the metal member 20.

[0025] The holding member 30 holds the metal member 20 in the electrolyte EL. For example, the holding member 30 may suspend the metal member 20 from below the holding member 30. More specifically, the holding member 30 may be composed of a columnar steel member 31 and a rope 33. The metal member 20 may be suspended by a rope 33 that is lowered vertically downward from the end of the steel member 31 that protrudes into the air. In Figure 1, "below the holding member 30" corresponds to the downward direction in the drawing. The steel member 31 may be fixed to the structure BS by fixing methods such as bolting or chemical anchors (registered trademark). One end of the rope 33 may be fixed to the steel member 31, and the other end of the rope 33 may be fixed to the metal member 20. In addition, the rope 33 may be fixed via a winch or the like to adjust the tension of the rope 33.

[0026] Furthermore, the retaining member 30 may anchor the metal member 20 to the bottom FL of the electrolyte EL flow path. For example, the retaining member 30 may consist of a weight 35 and a rope 37. The weight 35 may be installed at the bottom FL of the electrolyte EL flow path. One end of the rope 37 may be fixed to the weight 35, and the other end of the rope 37 may be fixed to the metal member 20.

[0027] In addition, the holding member 30 may hold the metal member 20 within a predetermined area horizontally separated from the corrosion-protected body 10. For example, in order to suppress the position of the metal member 20 from fluctuating due to the influence of the electrolyte EL flow, a predetermined tension may be applied to the rope 33 that suspends the metal member 20, and the weight 35 that moores the metal member 20 may have a weight greater than a predetermined amount.

[0028] Here, the "predetermined region" may be appropriately set depending on the conditions for forming the electrodeposited coating on the object to be protected from corrosion 10. Figure 1 shows that the distance between the object to be protected from corrosion 10 and the metal member 20 is distance DS1. In other words, the "predetermined region" is set at a position DS1 away from the surface of the object to be protected from corrosion 10. Distance DS1 may be set based on various conditions, such as the number of metal members 20 to be placed, the current density on the surface of the object to be protected from corrosion 10, and the area of ​​the object to be protected from corrosion 10 to which the electrodeposited coating is to be applied.

[0029] The configuration of the retaining member 30 and the method of holding the metal member 20 with the retaining member 30 are not limited to the examples given herein.

[0030] The wiring 40 electrically connects the metal member 20 and the corrosion-protected object 10. For example, the wiring 40 may be a busbar, harness, cable, wire, etc. The wiring 40 may be fixed to the retaining member 30 by fixing methods such as bolting or chemical anchoring. Alternatively, the wiring 40 may be welded to the metal member 20. In addition, a conductive rod electrically connected to the corrosion-protected object 10 may penetrate the structure BS, with the upper end of the rod exposed on the upper surface of the structure BS. The wiring 40 may then be fixed to this rod. This allows the wiring 40 and the corrosion-protected object 10 to be electrically connected using only ground work, thereby reducing the workload during construction. The rod can also be used for the purpose of checking whether or not voltage is applied to the corrosion-protected object 10 (checking the energization status).

[0031] The electrical contact between the wiring 40 and the corrosion-protected body 10 may be located in a part of the corrosion-protected body 10 that is not immersed in the electrolyte EL. For example, in Figure 1, the wiring 40 and the corrosion-protected body 10 are connected by welding at the welding site WD. The welding site WD is located in a part of the corrosion-protected body 10 that is not immersed in the electrolyte EL.

[0032] The method for fixing the wiring 40, and the method for electrical connection between the wiring 40 and the corrosion-protected body 10 and the metal member 20 are not limited to the examples given herein.

[0033] Figure 2 is a top view showing an example of the arrangement of metal components. Figure 2 shows how multiple metal components 20 are arranged, and it represents the electrodeposition coating apparatus 1 shown in Figure 1 as viewed from above the electrodeposition coating apparatus 1 with a line of sight pointing vertically downward.

[0034] The number of metal members 20 connected to a single welding area WD may be multiple. In Figure 2, eight metal members 20 are arranged, with four metal members 20 connected to one welding area WD. The metal members 20 are also arranged with a horizontal distance DS2 between them. The distance DS2 may be set based on various conditions, such as the number of metal members 20 to be arranged, the current density on the surface of the object to be protected from corrosion 10, and the area of ​​the object to be protected from corrosion 10 to which the electrodeposited coating is to be applied. The number of metal members 20 to be arranged and the manner of connection by wiring 40 are not limited to the examples given herein.

[0035] [Procedure for setting up the electrodeposition coating apparatus] Figure 3 shows an example of the procedure for setting up the electrodeposition coating apparatus. The order of each step included in the procedure shown in Figure 3 may be changed as long as it does not worsen work efficiency.

[0036] In step S101, a work platform is set up. For example, if access to the corrosion-protected object 10 is not easy, it is expected that connecting the wiring 40 to the corrosion-protected object 10 will be difficult. By setting up a work platform, the work of connecting the wiring 40 to the corrosion-protected object 10 will be made easier.

[0037] In step S103, the corrosion-protected body 10 and the wiring 40 are connected. For example, the worker welds the wiring 40 to the corrosion-protected body 10. Before welding, the worker may remove any rust, debris, etc., adhering to the welding area WD of the corrosion-protected body 10. Alternatively, the wiring 40 may be fixed to a conductive rod that is electrically connected to the corrosion-protected body 10, penetrates the structure BS, and has its upper end exposed on the upper surface of the structure BS.

[0038] In step S105, the retaining member 30 is installed. For example, the worker may fix the retaining member 30 to the structure BS using a fixing method such as bolting or chemical anchoring.

[0039] In step S107, the scaffolding used for the work is removed.

[0040] In step S109, the metal member 20 and the wiring 40 are connected. For example, the worker may connect the metal member 20 and the wiring 40 in a location less affected by the electrolyte EL, such as on a structural frame BS. Performing the work in a location away from the electrolyte EL helps to suppress a decrease in the worker's work efficiency.

[0041] In step S111, the metal member 20 is held via the holding member 30. For example, the worker places the metal member 20 into the electrolyte EL, and the holding member 30 holds the metal member 20 in the electrolyte EL. When the holding member 30 suspends the metal member 20, the worker may adjust the tension when suspending the metal member 20.

[0042] By following the procedure shown in Figure 3, the metal component 20 is placed in the electrolyte EL. In the electrolyte EL, due to the difference in ionization tendencies, a battery is formed in which the material to be protected from corrosion 10 becomes the positive electrode and the metal component 20 becomes the negative electrode. An electrodeposited film is formed on the surface of the material to be protected from corrosion 10 by the current flowing from the positive electrode to the negative electrode of the battery.

[0043] [Effects of the Embodiment] As described in detail above, the electrodeposition coating apparatus and electrodeposition coating method according to the present disclosure hold a metal member, which is less noble than the object to be protected, in the electrolyte via a holding member, and which constitutes the counter electrode of the object to be protected, which is at least partially immersed in the electrolyte, and electrically connect the metal member and the object to be protected by wiring.

[0044] This reduces the increase in workload and other factors when forming an electrodeposited coating on the object to be protected from corrosion. For example, it reduces the need to weld electrical contacts underwater to supply corrosion protection current to the object to be protected, eliminating the need to gather divers with the skills, experience, and qualifications for underwater welding. Furthermore, it reduces the need for external power sources, large-diameter wiring for distributing power from the external power source to each electrode, conductive materials, etc., which are necessary to supply sufficient corrosion protection current to the object to be protected from corrosion. As a result, the workload and operating costs can be reduced. Moreover, it is possible to form an electrodeposited coating on objects to be protected from corrosion in areas with strong currents and waves with less work and lower costs.

[0045] The metal component may have a greater ionization tendency than aluminum. This allows for the construction of a battery in which the corrosion-protected material is the positive electrode and the metal component is the negative electrode.

[0046] The metal component may be made of magnesium or an alloy in which magnesium is the main element. This allows for a larger current to flow from the positive electrode to the negative electrode of the constructed battery, and provides a sufficient corrosion-preventive current to form the electrodeposited coating.

[0047] The corrosion-protected object may be made of iron or an alloy with iron as the main element. This allows for the construction of a battery in which the corrosion-protected object is the positive electrode and the metal component is the negative electrode. Furthermore, electrodeposited coatings can be formed on harbor steel structures such as steel sheet piles and steel pipe piles, marine steel structures such as bridge caissons, floating structures, and ships, and underwater steel structures in brackish water areas such as sluice gates.

[0048] The electrical contacts between the wiring and the material to be protected from corrosion may be located in areas of the material that are not immersed in the electrolyte. This reduces the need to weld the electrical contacts for supplying the protective current to the material underwater, eliminating the need to assemble a team of divers with the skills, experience, and qualifications for underwater welding.

[0049] The holding member may be one which suspends the metal member from below. This allows the position of the corrosion-protected object to change in accordance with the flow of the electrolyte. Therefore, damage and deterioration of the metal member and the holding member due to the flow of the electrolyte are suppressed, and the current necessary for forming the electrodeposited coating can be stably supplied. In addition, the workload when installing or removing the metal member can be reduced.

[0050] The retaining member may anchor the metal member to the bottom of the electrolyte flow path. This allows the position of the object to be protected from corrosion to change in accordance with the electrolyte flow. Therefore, damage and deterioration of the metal member and retaining member due to the electrolyte flow are suppressed, and the current necessary for forming the electrodeposited coating can be stably supplied.

[0051] The holding member may be one that holds a metal member within a predetermined area spaced apart from the object to be protected from corrosion. This allows for a stable supply of the current necessary to form the electrodeposited coating, enabling the formation of the desired electrodeposited coating on the surface of the object to be protected from corrosion.

[0052] A battery may be constructed with the material to be protected from corrosion as the positive electrode and a metal component as the negative electrode, and an electrodeposited film may be formed on the surface of the material to be protected from corrosion by the current flowing from the positive electrode to the negative electrode. In this way, an electrodeposited film can be formed on the surface of the material to be protected from corrosion by depositing cations dissolved in the electrolyte as electrodeposited material. For example, on the surface of the material to be protected from corrosion, Ca 2+ Ions or Mg 2+ By electrolyzing ions to deposit them as an electrodeposited material mainly composed of CaCO3 or Mg(OH)2, an electrodeposited coating can be formed on the surface of the object to be protected from corrosion.

[0053] According to this disclosure, it is possible to suppress the increase in workload when forming an electrodeposited coating on the object to be protected from corrosion, thereby improving the durability and extending the lifespan of infrastructure equipment having the object to be protected from corrosion. Therefore, for example, it can contribute to Goal 9 of the United Nations Sustainable Development Goals (SDGs), "Build resilient infrastructure, promote inclusive and sustainable industrialization and drive innovation."

[0054] Although several embodiments have been described, it is possible to modify or transform the embodiments based on the above disclosure. All components of the above embodiments, and all features described in the claims, may be taken individually and combined, provided that they do not conflict with each other. [Explanation of Symbols]

[0055] 1 Electrocoating film forming device 10. Protected from being eaten 20 metal parts 30 Maintaining parts 31 Steel 33,37 ロープ 35 hammers 40 wiring BS structure Distance between DS1 and DS2 EL electrolyte FL bottom WD welding part

Claims

1. A metal member less noble than the corrosion-prevented material, which constitutes the counter electrode of the corrosion-prevented material that is at least partially immersed in the electrolyte, A holding member that holds the metal member in the electrolyte, Wiring that electrically connects the metal member and the object to be protected from corrosion, An electrodeposition coating forming apparatus equipped with the following features.

2. The electrodeposition coating forming apparatus according to claim 1, wherein the metal member has a greater ionization tendency than aluminum.

3. The electrodeposition coating apparatus according to claim 1, wherein the metal member is made of magnesium or an alloy having magnesium as the main element.

4. The electrodeposition coating forming apparatus according to claim 1, wherein the corrosion-protected body is made of iron or an alloy having iron as the main element.

5. The electrodeposition coating apparatus according to claim 1, wherein the electrical contact between the wiring and the object to be protected from corrosion is installed in a part of the object to be protected from corrosion that is not immersed in the electrolyte.

6. The electrodeposition coating forming apparatus according to claim 1, wherein the holding member suspends the metal member below the holding member.

7. The electrodeposition coating apparatus according to claim 1, wherein the holding member anchors the metal member to the bottom of the electrolyte flow path.

8. The electrodeposition coating forming apparatus according to claim 1, wherein the holding member holds the metal member within a predetermined area spaced apart from the object to be protected from corrosion.

9. A battery is constructed in which the corrosion-resistant material is the positive electrode and the metal member is the negative electrode. An electrodeposited coating forming apparatus according to any one of claims 1 to 8, wherein an electrodeposited coating is formed on the surface of the object to be protected from corrosion by an electric current flowing from the positive electrode to the negative electrode.

10. A metal member less noble than the corrosion-prevented material, which constitutes the counter electrode of the corrosion-prevented material that is at least partially immersed in the electrolyte, is held in the electrolyte via a holding member. The metal member and the corrosion-resistant body are electrically connected by wiring. Electrodeposition film formation method.

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