JPH10245700A - Method for degreasing and washing conductive member and method for degreasing and washing piping - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to wash conductive members, etc., of intricate shapes without using org. solvents and consequently to solve environmental problems, productivity, waste water treatment problems, etc. SOLUTION: The conductive member 14 having foreign matter, such as oil, rust and dirt, on the surfaces is formed as a cathode 15 and metallic electrodes as anodes 13. The anodes and the cathode are immersed into an electrolyte 11 and voltage is impressed between the anodes and cathode in the electrolyte to pass current between the electrodes, by which air bubbles 18 are continuously generated on the surfaces of the conductive member. The foreign matter is removed from the surfaces of the conductive member by the mechanical stirring generated by these air bubbles.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for degreasing and cleaning a conductive member having foreign matters on its surface and a method for degreasing a pipe.

[0002]

2. Description of the Related Art Generally, various manufacturing processes have a cleaning process before a plating process or a coating process of a conductive part. This cleaning step is performed to clean the surface of the member having stains or the like in the course of manufacturing or processing, and to obtain an active surface suitable for plating.

[0003] Such degreasing cleaning methods before plating and coating include solvent cleaning, emulsion cleaning, alkali cleaning, and the like. In the industrial field, environmental problems, wastewater treatment problems, and productivity are usually considered. Alkaline cleaning is widely used.

[0004]

However, in the above degreasing cleaning method, as shown in FIGS. 5A and 5B, a conductive member 2 having a complicated shape having a blind screw hole 1 and the like is cleaned. However, there is a problem that the cleaning power of the alkali cleaning is insufficient.

Therefore, an organic solvent is used for the conductive member 2 having a complicated shape. That is, this is a two-step cleaning process in which the substrate is immersed in an alkaline solution after the organic cleaning.

However, the use of an organic solvent for cleaning only the blind screw hole 1 causes problems such as environmental problems and reduction in productivity. The present invention has been made in consideration of the above circumstances, without using an organic solvent, can wash a conductive member having a complicated shape and the like, thereby, environmental problems, productivity,
An object of the present invention is to provide a method for degreasing and cleaning a conductive member and a method for degreasing and cleaning a pipe, which can solve a wastewater treatment problem and the like.

[0007]

According to the present invention, a conductive member having foreign matters such as oil, rust and dirt on its surface is a cathode, a metal electrode is an anode, and the anode and the cathode are electrolytically treated. Immersing in a liquid, and applying a voltage between the anode and the cathode in the electrolytic solution to cause a current to flow between the two electrodes, thereby continuously generating bubbles on the surface of the conductive member; Removing the foreign matter from the surface of the conductive member by mechanical agitation by the air bubbles.

According to a second aspect of the present invention, in the method for degreasing and cleaning a conductive member according to the first aspect, the conductive member in the dipping step includes a blind screw hole formed by a thread cutting step. This is a method for degreasing and cleaning a conductive member, which is an unfinished member.

Further, the invention corresponding to claim 3 is a method for degreasing and cleaning a conductive member according to claim 1, wherein the electrolytic solution is a degreasing and cleaning method for a conductive member using an alkaline solution.

According to a fourth aspect of the present invention, there is provided the conductive member degreasing method according to the first aspect, wherein the current density of the current is in the range of ^{20 to} 30 A / m ² . This is a method for degreasing and cleaning members.

The invention according to claim 5 is a method for degreasing and cleaning a conductive member according to claim 1, wherein the current is supplied for a time within a range of 3 to 5 minutes. This is a degreasing cleaning method.

According to a sixth aspect of the present invention, in the method for degreasing and cleaning a conductive member according to the first aspect, the temperature of the electrolytic solution is in a range of 50 to 60 ° C. Degreasing cleaning method.

Further, the invention corresponding to claim 7 is the method for degreasing and cleaning a conductive member according to claim 2, which is a method for degreasing and cleaning a conductive member using a painting step instead of the plating step.

An eighth aspect of the present invention is the method for degreasing and cleaning a conductive member according to the first aspect, wherein the conductive member is a method for degreasing and cleaning a conductive member having a mesh shape.

According to a ninth aspect of the present invention, there is provided a method for degreasing and cleaning a conductive member according to the first aspect, wherein the conductive member is an electrode of a conductivity meter installed in an electrolyte such as sewage. This is a method for degreasing and cleaning the conductive member.

According to a tenth aspect of the present invention, a cathode member is provided in an electrolytic solution, such as seawater, having foreign matter such as dirt on an inner wall thereof along the inner wall of the pipe. And a step of disposing an anode member in the electrolytic solution inside the pipe, and applying a voltage between the anode member and the cathode member in the electrolytic solution to cause a current to flow between the two electrodes. Accordingly, a method for degreasing and cleaning a pipe includes a step of continuously generating bubbles on the surface of the cathode member, and a step of removing the foreign matter from the inner wall of the pipe by mechanical stirring by the bubbles. (Action) Therefore, the invention corresponding to claim 1 takes the above-described means, so that a conductive member having foreign substances such as oil, rust, and dirt on its surface is used as a cathode, a metal electrode is used as an anode, and an anode is used as an anode. And, by immersing the cathode in the electrolytic solution, applying a voltage between the anode and the cathode in the electrolytic solution and causing a current to flow between the two electrodes, bubbles are continuously generated on the conductive member surface, and By removing foreign matter from the surface of the conductive member by mechanical stirring, it is possible to wash the conductive member having a complicated shape without using an organic solvent.
It is possible to solve problems such as productivity and wastewater treatment.

According to a second aspect of the present invention, the conductive member in the dipping step is an unfinished member having a blind screw hole formed by the thread cutting step. For example, as a plating pretreatment or a coating pretreatment, oil adhering to the surface of the conductive member can be relatively easily, economically, and surely completely removed from the set screw portion.

Further, in the invention according to claims 3, 4, 5, and 6, the electrolytic solution uses an alkaline solution, the current density of the current is in the range of ²⁰ to 30 A / m ² , and the current flows. The time is in the range of 3 to 5 minutes, and the temperature of the electrolytic solution is 50 minutes.
Since the electrolysis conditions are appropriately defined as being within the range of 範 囲 60 ° C., the actions corresponding to claim 1 can be easily and reliably achieved.

Further, in the invention corresponding to claim 7, since the coating step is used instead of the plating step corresponding to claim 2, the same operation as that of claim 2 can be achieved.

In the invention according to claim 8, since the conductive member has a mesh shape, the same function as that of claim 1 can be achieved with a conductive filter, for example.

According to a ninth aspect of the present invention, the conductive member is a conductivity meter electrode installed in an electrolyte such as sewage. By removing the dirt, the measurement error of the conductivity meter is reduced, so that the reliability of the conductivity meter can be improved.

According to a tenth aspect of the present invention, a cathode member is disposed in an electrolytic solution along an inner wall of a pipe with respect to a pipe provided in an electrolytic solution such as seawater and having foreign matter such as dirt on the inner wall. Then, the anode member is arranged in the electrolytic solution inside the pipe, and a voltage is applied between the anode member and the cathode member in the electrolytic solution to flow a current between the two electrodes. Since air bubbles are generated in the air and the foreign matter is removed from the inner wall of the pipe by mechanical stirring by the air bubbles, even if the object to be cleaned is an insulating material, the same operation as that of claim 1 can be achieved. .

[0023]

Next, embodiments of the present invention will be described with reference to the drawings. (First Embodiment) FIG. 1 is a schematic diagram showing a configuration of a cleaning apparatus to which a degreasing cleaning method according to a first embodiment of the present invention is applied. The cleaning apparatus is provided with a bath 12 for holding an electrolyte 11, an anode 13 immersible in the electrolyte 11 in the bath 12, and a workpiece 14 immersible in the electrolyte 11 in the bath 12. DC power supply 1 capable of applying a positive voltage to anode 13 and applying a negative voltage to cathode 15
6 is provided.

Here, as the electrolytic solution 11, an alkali degreasing solution can be used. As a specific alkali degreasing solution, a mixed solution of phosphate, silicate, carbonate and various surfactants (trade name Pakuna 150Y) is used.

The object 14 can be made of a conductive material. Here, a conductive member 2 having a blind screw hole 1 as shown in FIG. 5 is used. The conductive member 2 is after a thread cutting step using a lubricating oil, and is carried to a plating step or a coating step after degreasing and washing according to the present embodiment.

The anode 13 can be made of, for example, platinum or copper. Here, platinum is used. Next, a degreasing cleaning method using the cleaning apparatus configured as described above will be described.

Now, the conductive member 2 which is the object to be processed 14 is placed on the cathode 15 side, and is immersed in the electrolytic solution 11 at 50 to 60 ° C. Subsequently, the DC power supply 16 applies a voltage between the anode 13 and the cathode 15 in the electrolytic solution 11 and causes a current having a current density of 20 to 30 A / m ² to flow between both electrodes for 3 to 5 minutes.

By this electric current, water is electrolyzed, and bubbles of oxygen gas 17 are continuously generated at the anode 13.
Hydrogen gas 18 is continuously applied to the surface of the conductive member 2 of the cathode 15.
Bubbles are generated.

Foreign matter such as lubricating oil is removed from the surface of the conductive member 2 by the mechanical stirring of the cathode 15 by air bubbles and the cathode reduction. That is, according to this embodiment, since the conductive member 2 having a complicated shape can be washed without using an organic solvent, it is possible to solve environmental problems, productivity, wastewater treatment problems, and the like.

Further, the conductive member 2 is an unfinished member having the blind screw hole 1, but as a pretreatment for plating, oil adhering to the surface of the conductive member 2 is relatively easily and economically manufactured. Moreover, the oil in the blind screw hole 1 can be completely removed without fail.

Further, the electrolytic solution 11 uses an alkaline solution, the current density of the current is in the range of ²⁰ to 30 A / m ² , the current flowing time is in the range of 3 to 5 minutes, Since the electrolysis conditions are appropriately defined such that the liquid temperature of No. 11 is in the range of 50 to 60 ° C., the above-described cleaning effect can be easily and reliably achieved.

In the present embodiment, the description has been made of the case where the mechanical agitation using the bubbles of the hydrogen gas 18 on the cathode 15 side is used. Good. For example, ultrasonic cleaning or stirring with a stirrer may be used in combination. (Second Embodiment) In a second embodiment of the present invention, the conductive member 2 of the first embodiment is replaced with a tea strainer. That is, the conductive member 20 of the present embodiment has a mesh shape as shown in a partially enlarged view in FIG. 2, and is specifically a tea strainer to which brown paste is adhered.

As described above, the conductive member 20 having the mesh shape can generate the hydrogen gas 18 from the surface of the conductive member 2a and remove the persistent brown spots on the surface of the brown strainer by mechanical stirring. Was.

The degreasing cleaning was carried out under various conditions. For example, as the electrolytic solution 11, a commercially available alkaline detergent solution comprising sodium hypochlorite (chlorine) and a surfactant (Kitchen Highter, Kao (trade name)) Co., Ltd.)
The conductive member 20 subjected to cathodic reduction electrolysis at a current density of 30 A / m ² , an electrolysis time of 10 minutes, and an electrolytic solution 11 at a temperature of 20 to 25 ° C. is 3
A clean appearance equivalent to that immersed in a commercially available alkaline detergent solution (same as above) for 0 minutes was obtained.

As described above, according to this embodiment, the same effect as that of the first embodiment can be obtained even when the mesh-shaped conductive member 20 is used. Further, in the present embodiment, the case where the conductive member 20 has a mesh shape has been described, but it is needless to say that the present invention is not limited to this, and an arbitrary shape such as a stripe shape can be applied. (Third Embodiment) Next, a third embodiment of the present invention will be described with reference to the drawings. FIG. 3 is a schematic view for explaining a method of degreasing and cleaning a pipe according to a third embodiment of the present invention. As shown in the drawing, a mesh-shaped conductive member 22 (cathode) is provided in the electrolyte along the inner wall of the sewer pipe 21 with respect to the sewer pipe 21 provided in the electrolyte such as seawater and having foreign matter such as dirt on the inner wall. Members) are arranged. Also, the anode metal wire 23
Is arranged.

Here, as described above, by applying a voltage between the anode and the cathode in the electrolytic solution and causing a current to flow between the two electrodes, bubbles are continuously generated on the surface of the conductive member 22. In addition, foreign substances can be removed from the inner wall of the sewer pipe 21 by mechanical stirring using bubbles.

As described above, according to the present embodiment, even if the object to be cleaned is an insulator, the air bubbles from the conductive member 22 are caused to collide with the sewerage pipe 21 in the same manner as in the first embodiment. The effect can be obtained.

Since it is difficult to adjust the concentration of the electrolyte and the temperature, the cleaning effect is lower than in the first and second embodiments. However, by using the cathodic reduction electrolysis method of the present embodiment together with the alkali cleaning at the time of cleaning the sewer pipe 21, it is possible to remove foreign substances (dirty substances) attached to the inner wall of the sewer pipe 21.

In the present embodiment, the case where the sewer pipe 21 is cleaned has been described. However, the present invention is not limited to this, and it goes without saying that other pipes may be used. In addition, the sewerage pipe in seawater has been described as an example, but the present invention is not limited to this, and it goes without saying that the present invention can be applied to any pipe in which an electrolyte flows. (Fourth Embodiment) In a fourth embodiment of the present invention, the conductive member 2 of the first embodiment is replaced with a conductivity meter electrode 30. That is, the conductive member of the present embodiment is the same as that of FIG.
As shown in the figure, the electrode 30 is inside the conductivity meter 31.
Further, the electrolyte solution 11 may be injected from the solution injection port 32 of the conductivity meter 31.

Even if the conductivity meter electrode 31 as described above is used as a conductive member, hydrogen gas 18 is generated from the surface of the conductivity meter electrode 30 as described above, and the surface of the conductivity meter electrode 30 is contaminated by mechanical stirring. Things could be removed.

That is, according to the present embodiment, the same effects as those of the first embodiment can be obtained. Further, the conductivity meter 31 has a complicated electrode structure and is difficult to clean. If a contaminant adheres to the conductivity meter electrode 30, an error occurs in a measured value and reliability is reduced. However, in the present embodiment, as described above, since the contaminants on the surface of the conductivity meter electrode 30 can be removed, the measurement function of the conductivity meter 31 can be returned to normal, and the reliability can be restored.

Although the case where the conductivity meter 31 is degreased and cleaned by the cleaning device shown in FIG. 1 has been described, the present invention is not limited to this. And the sewage or the like measured by the conductivity meter 31 may be used for the electrolyte 11. That is, at the installation location of the conductivity meter 31, the cathode 15 is connected to the conductivity meter electrode 30,
The anode 13 is immersed in sewage or the like.
A current may flow between 6 and both electrodes 13 and 15.

[0043]

Next, the results of an examination of the electrolytic conditions for the degreasing and cleaning method of the present invention will be described. The electrolysis conditions include items such as the electrolytic solution 11, the current density, the electrolytic time, and the temperature of the electrolytic solution 11. (Electrolyte 11) In the selection of the electrolyte 11, there are three solutions: an acidic solution (sulfuric acid), a neutral solution (potassium chloride), and an alkaline degreasing solution.
The types were compared. The alkaline degreasing solution is a phosphate,
It is a mixture of silicate, carbonate and various surfactants (trade name Pakna 150Y), and the same applies to the following selection.
As a specific selection, three copper plates to which oil was adhered were individually immersed in each solution, and the appearances after immersion and after cathodic reduction electrolysis were compared. Table 1 shows the evaluation results for each electrolytic solution 11.

[0044]

[Table 1]

From Table 1, it can be considered that the electrolyte solution 11 is optimally an alkaline degreasing solution. (Current density) In selecting the current density, 10, 20, 30 A
/ M ² were compared. Specifically, three copper plates to which oil was attached were individually immersed in each solution, and each current density was 1
Cathodic reduction electrolysis was performed at 0, ²⁰ , and 30 A / m ² , and the appearance was compared. Other electrolysis conditions are as follows: the electrolysis solution 11 is an alkaline degreasing solution, the electrolysis time is 3 minutes, and the electrolysis temperature is 40 to 45 ° C. Table 2 shows the evaluation results for each current density.

[0046]

[Table 2]

According to Table 2, the current density was 20 to 30 A / m ^2.
Is considered optimal. (Electrolysis time) In selecting the electrolysis time, each of 1, 3, and 5 minutes was compared.

In the same manner as described above, three copper plates to which oil was adhered were individually immersed in the respective solutions, and subjected to cathodic reduction electrolysis for 1, 3, and 5 minutes for each electrolysis time, and the appearances were compared. Other electrolysis conditions are as follows: the electrolyte solution 11 is an alkaline degreasing solution, the current density is 20 A / m ² , and the electrolysis temperature is 40 to 45 ° C. Table 3 shows the evaluation results for each electrolysis time.

[0049]

[Table 3]

From Table 3, it is considered that the optimal electrolysis time is 3 to 5 minutes. (Liquid temperature of electrolytic solution 11) In selecting the liquid temperature of electrolytic solution 11, 2
Each of 0 to 25 ° C, 40 to 45 ° C, and 55 to 60 ° C was compared.

In the same manner as described above, the three copper plates to which the oil was adhered were individually immersed in each solution, and subjected to cathodic reduction electrolysis at each electrolysis time of 1, 3, and 5 minutes, and the appearance was compared. Other electrolysis conditions are as follows: the electrolyte solution 11 is an alkaline degreasing solution, the current density is 20 A / m ² , and the electrolysis time is 3 minutes. Table 4 shows the evaluation results of the electrolytic solution 11 for each liquid temperature.

[0052]

[Table 4]

From Table 4, it can be seen that the temperature of the electrolytic solution 11 is 40 to 45.
C. is preferred, but 55-60.degree. C. is considered optimal. (Results) To summarize the above, the optimal electrolysis conditions are:
The electrolytic solution 11 is an alkaline degreasing solution and has a current density of 20 to
30 A / m ² , the electrolysis time is 3 to 5 minutes, and the temperature of the electrolytic solution 11 is 55 to 60 ° C. (Available selection result) The current density is loaded,
It may exceed 30 A / m ² . The electrolysis time increases the processing time, but may exceed 5 minutes. Further, the temperature of the electrolytic solution 11 increases the amount of heat required for heating, but may exceed 60 ° C.
It may be 54 ° C. Any range, preferably between 40 and 60 ° C, for example 50 to 60 ° C, is applicable.
In addition, the present invention can be implemented with various modifications without departing from the scope of the invention.

[0054]

As described above, according to the present invention, a conductive member having a complicated shape can be washed without using an organic solvent, thereby solving environmental problems, productivity, wastewater treatment problems, and the like. A method for degreasing and cleaning a conductive member and a method for degreasing and cleaning a pipe can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of a cleaning apparatus to which a degreasing cleaning method according to a first embodiment of the present invention has been applied.

FIG. 2 is an enlarged view showing a part of a conductive member according to a second embodiment of the present invention.

FIG. 3 is a schematic view for explaining a method of degreasing and cleaning a pipe according to a third embodiment of the present invention.

FIG. 4 is a schematic diagram for explaining a method of degreasing and cleaning a conductivity meter electrode according to a fourth embodiment of the present invention.

FIG. 5 is a schematic view showing a configuration of a conductive member having a general blind screw hole;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Stop screw hole part 2, 20, 22 ... Conductive member 11 ... Electrolyte solution 12 ... Bathtub 13 ... Anode 14 ... Workpiece 15 ... Cathode 16 ... DC power supply 21 ... Sewer pipe 23 ... Anode metal wire

Continuing on the front page (72) Inventor Sadao Ida 1 Toshiba-cho, Fuchu-shi, Tokyo In the Toshiba Fuchu Plant, Inc. (72) Inventor Satoshi Haraguchi 1 Toshiba-cho, Fuchu-shi, Tokyo, Toshiba Fuchu Plant (72) Inventor Person Masao Kaneko 1 Toshiba-cho, Fuchu-shi, Tokyo, Japan Inside the Fuchu Plant, Toshiba Corporation (72) Inventor Ichiro Yamaguchi 1st place, Toshiba-cho, Fuchu-shi, Tokyo, Japan Inside the Fuchu Plant, Toshiba Corporation (72) Kenichi Okuno Toshiba, Fuchu-shi, Tokyo No. 1, Toshiba Corporation Fuchu Plant

Claims (10)

[Claims] 1. A step in which a conductive member having foreign substances such as oil, rust and dirt on its surface is used as a cathode, a metal electrode is used as an anode, and the anode and the cathode are immersed in an electrolyte. Applying a voltage between the two electrodes and applying a voltage between the two electrodes to continuously generate bubbles on the surface of the conductive member; and mechanically agitating the bubbles to form the conductive member. Removing the foreign matter from the surface. 2. The method of degreasing and cleaning a conductive member according to claim 1, wherein the conductive member in the immersion step is an unfinished member having a blind screw hole formed by a thread cutting step. Cleaning method for a conductive member to be performed. 3. The method for degrease and cleaning a conductive member according to claim 1, wherein an alkaline solution is used as the electrolytic solution. 4. The method for degrease and cleaning a conductive member according to claim 1, wherein the current density of the current is in a range of ^{20 to} 30 A / m ^2. . 5. The method for degrease and cleaning a conductive member according to claim 1, wherein the time for flowing the electric current is within a range of 3 to 5 minutes. 6. The method for degrease and cleaning a conductive member according to claim 1, wherein the temperature of the electrolytic solution is in a range of 50 to 60 ° C. 7. The method for degrease and cleaning a conductive member according to claim 2, wherein a coating step is used instead of the plating step. 8. The degreasing method for a conductive member according to claim 1, wherein the conductive member has a mesh shape. 9. The conductive member according to claim 1, wherein the conductive member is a conductivity meter electrode installed in an electrolytic solution such as sewage. Degreasing cleaning method. 10. A pipe provided in an electrolyte such as seawater and having foreign matter such as dirt on an inner wall thereof, a step of disposing a cathode member in the electrolyte along the inner wall of the pipe; A step of disposing an anode member in an inner electrolyte solution, by applying a voltage between the anode member and the cathode member in the electrolyte solution and causing a current to flow between the two electrodes, to continuously connect to the surface of the cathode member. A method for degreasing and cleaning a pipe, the method including: a step of generating air bubbles; and a step of removing the foreign matter from an inner wall of the pipe by mechanical stirring by the air bubbles.