JP2011184786A - Method of cleaning metallic member and apparatus thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of cleaning a metallic member by which the metallic member is dried by efficiently removing a cleaning liquid using an aqueous solution or an organic solvent from the surface of the metallic member after cleaning the surface of the metallic member with the cleaning solution and when using the organic solvent, the organic solvent is recovered while suppressing the diffusion of the organic solvent in the atmosphere to the utmost. <P>SOLUTION: In the method of cleaning the metallic member by cleaning the surface of the metallic member with the cleaning liquid and drying the metallic member to remove the cleaning liquid from the surface of the metallic member, the metallic member is dried using a drying apparatus 2 constituted so that a distribution channel of a gas is turned into a closing system circulating rout by connecting a gas circulating pipe 6, a gas-liquid separator 7 and a pump 8 or a blower through a pipe line 9. The gas circulating pipe 6 has an inlet 3 and an outlet 4 in the side wall through which the metallic member 1 is passed and has a nozzle 5 arranged inside so as to discharge a gas therein toward the metallic member 1 passed through the inlet 3 and the outlet 4. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a metal member cleaning method and apparatus for cleaning the surface of a metal member with a cleaning liquid using an organic solvent such as xylene or an aqueous solution, and then drying the metal member to remove the cleaning liquid from the surface of the metal member. It is about.

  For example, in the case of manufacturing an insulated wire in which an insulating coating is formed on a conductor to form an insulating layer, the surface of the conductor wire formed through a wire drawing process or a rolling process has a metal powder generated during processing. Or lubricating oil for processing.

  In addition, the thickness of the insulation layer of the insulated wire formed on the conductor is steadily becoming thinner due to the demands on the electrical characteristics of the insulated wire based on its usage, and it adheres to the surface of the conductor wire. It has been pointed out that if the insulating coating is applied to the surface in the next step without sufficiently removing the metal powder or lubricating oil, the insulation performance of the insulated wire is reduced.

  In order to remove metal powder or lubricating oil adhering to the surface of the conductor wire, the cleaning ability is improved by immersing the wire in a cleaning solution using an organic solvent and irradiating with ultrasonic waves as necessary. A method of cleaning the surface of the wire by raising it is widely adopted.

  Further, in this cleaning method using an organic solvent, it is necessary to clean the surface of the wire with a cleaning liquid using an organic solvent, and then dry the wire to remove the cleaning liquid from the surface of the wire. A so-called air blow method, in which air is blown at high speed on the surface of the wire to dry it, is generally employed.

  For example, Patent Literature 1 as a prior art document describes an air blow type dryer that blows air onto the surface of a wire after being cleaned with a cleaning liquid, and blows off the cleaning liquid adhering to the surface of the wire to dry it. ing.

Japanese Patent No. 3567112

  In a conventional wire drying method called air blow, when water is used as a cleaning liquid, there is a problem that a large amount of energy is required to evaporate the water. As shown in Table 1, the energy required for water evaporation, that is, latent heat of evaporation, is 3 to 7 times as large as that of other organic solvents. Therefore, a large heat source is required to evaporate and dry all the water adhering to the conductor surface.

  According to a conventional wire drying method called air blow, there is a problem that the organic solvent is scattered and volatilized when the cleaning liquid is removed from the surface of the wire. Volatile organic solvents diffuse into the atmosphere as so-called VOCs (Volatile organic compounds), but this VOC can cause photochemical oxidants and may cause air pollution.

  In addition, in order to collect VOCs diffused in the atmosphere, it is necessary to separate the VOCs by sucking the volume of air that is hundreds or thousands of times larger than that, and a large-scale facility is required.

  In view of such problems, an object of the present invention is to effectively remove the cleaning liquid from the surface of the metal member by a method other than evaporation in the step of contacting the metal member with the cleaning liquid to remove the deposit on the surface of the metal member. .

  Another object of the present invention is to recover the organic solvent removed from the surface of the metal member while minimizing the amount dissipated to the atmosphere, particularly when the cleaning liquid is an organic solvent.

  In order to achieve the above object, the invention of claim 1 is a method for cleaning a metal member, wherein the surface of the metal member is cleaned with a cleaning liquid, and then the metal member is dried to remove the cleaning liquid from the surface of the metal member. A gas distribution pipe having an inlet and an outlet through which a metal member passes on the side wall and a nozzle arranged so that gas therein is discharged toward the metal member passing between the inlet and the outlet; A metal member, wherein a separator and a pump or a blower are connected by a pipe, and the metal member is dried using a drying device configured such that the gas circulation path is a closed circulation path. A cleaning method is provided.

  In the above, the gas discharged toward the metal member in the gas flow pipe of the drying device is a gas that removes the cleaning liquid from the surface of the metal member and mists the removed cleaning liquid into a gas-liquid separator. Pass through. In a gas-liquid separator, an aqueous solution or an organic solvent is recovered by separating mist from such a gas. Further, the gas that has passed through the gas-liquid separator is sent to the gas flow pipe through a pipe by a pump or a blower, so that the gas flow path becomes a so-called closed system circulation path as a whole. As the gas-liquid separator, it is preferable to use a type that separates an aqueous solution or an organic solvent from a gas condensed and liquefied by a condenser.

  According to this method for cleaning a metal member, by adopting the above configuration, in particular, by using the drying apparatus, for example, after cleaning the surface of the metal member with a cleaning solution using an aqueous solution or an organic solvent, The metal member can be dried by removing the cleaning liquid from the surface, and when the organic solvent is used as the cleaning liquid, the organic solvent can be recovered while suppressing the diffusion of the organic solvent into the atmosphere as much as possible. As a result, it is possible to suppress the occurrence of VOC, reduce the environmental impact such as air pollution, and improve the working environment.

  The invention according to claim 2 provides the metal member cleaning method according to claim 1, wherein the nozzle has a gas introduction part that is closely joined to the inner wall of the gas flow pipe in the preceding stage. .

  According to this metal member cleaning method, in addition to the above-described effects, the adoption of the above configuration allows the gas in the gas flow pipe to be guided by the gas introduction portion without being leaked and discharged through the nozzle. By increasing the wind speed of the gas, the metal member can be effectively dried and the cleaning liquid can be sufficiently removed from the surface of the metal member.

  A third aspect of the present invention provides the method for cleaning a metal member using an organic solvent according to the first or second aspect, wherein the flow rate of the gas discharged through the nozzle is 45 m / second or more. .

  According to this metal member cleaning method, in addition to the above effects, the adoption of the above configuration allows the wind speed of the gas discharged through the nozzle to be the wind speed necessary for the cleaning liquid to peel from the surface of the metal member based on experiments. Therefore, the metal member can be quickly and effectively dried to sufficiently remove the cleaning liquid from the surface of the metal member.

  According to a fourth aspect of the present invention, there is provided a cleaning apparatus for a metal member, wherein the metal member is dried by cleaning the surface of the metal member with a cleaning liquid, and the cleaning liquid is removed from the surface of the metal member. A gas flow pipe having a nozzle and a gas-liquid separator, and a pump having an inlet and an outlet configured to discharge gas therein toward a metal member surface passing between the inlet and the outlet. Alternatively, the present invention provides a metal member cleaning device comprising a drying device that is connected to a blower by a pipe and the gas flow path is a closed circulation path.

  According to this metal member cleaning apparatus, by adopting the above configuration, in particular, by including the drying apparatus, for example, after cleaning the surface of the metal member with a cleaning solution using an aqueous solution or an organic solvent, the metal member is effectively The metal member can be dried by removing the cleaning liquid from the surface of the member, and when the organic solvent is used as the cleaning liquid, the organic solvent can be recovered while suppressing the diffusion of the organic solvent into the atmosphere as much as possible. As a result, it is possible to suppress the occurrence of VOC, reduce the environmental impact such as air pollution, and improve the working environment. Further, there is an effect that a large-scale facility is not required for the recovery of the organic solvent.

  According to a fifth aspect of the present invention, there is provided the metal member cleaning apparatus according to the fourth aspect, wherein the nozzle has a gas introduction portion that is closely joined to the inner wall of the gas flow pipe at the preceding stage. .

  According to this metal member cleaning apparatus, in addition to the above-described effects, the adoption of the above configuration allows the gas in the gas flow pipe to be guided through the gas introduction section without being leaked and discharged through the nozzle. By increasing the wind speed of the gas, the metal member can be effectively dried and the cleaning liquid can be sufficiently removed from the surface of the metal member.

  A sixth aspect of the present invention provides the cleaning apparatus for a metal member according to the fourth or fifth aspect, wherein the flow rate of the gas discharged through the nozzle is 45 m / second or more.

  According to this metal member cleaning apparatus, in addition to the above-described effect, the adoption of the above-described configuration allows the flow rate of the gas discharged through the nozzle to be the flow rate necessary for the cleaning liquid to peel from the surface of the metal member based on experiments. Therefore, the metal member can be quickly and effectively dried to sufficiently remove the cleaning liquid from the surface of the metal member.

  According to the method and apparatus for cleaning a metal member of the present invention, after cleaning the surface of the metal member with a cleaning solution using an aqueous solution or an organic solvent, the metal member is effectively removed by removing the cleaning liquid from the surface of the metal member. When the organic solvent is used as the cleaning liquid, the organic solvent can be recovered while suppressing the diffusion of the organic solvent into the atmosphere as much as possible.

It is a schematic explanatory drawing of the washing | cleaning method of the metal member which concerns on one embodiment of this invention, and its apparatus. It is explanatory drawing of the nozzle peripheral part in the gas distribution pipe which concerns on one embodiment of this invention. It is a figure which shows the relationship between the flow rate of gas required for peeling of a washing | cleaning liquid, and the frequency | count required to pass a gas distribution pipe.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to FIGS.

  In FIG. 1, 1 is a copper wire as a metal member drawn by a drawing die (not shown). The copper wire 1 is subjected to surface cleaning with a cleaning solution using an organic solvent such as xylene (not shown) in order to remove deposits such as metal powder and processing lubricant generated during wire drawing, and then dried. In order to remove the cleaning liquid from the surface, it is introduced into the drying device 2.

  The drying device 2 has an inlet 3 and an outlet 4 through which the copper wire 1 passes on the side wall, and a gas therein is discharged toward the copper wire 1 passing between the inlet 3 and the outlet 4 inside. The gas flow pipe 6 in which the nozzle 5 is arranged, the gas-liquid separator 7, and the pump 8 or the blower are connected by a pipe 9 so that the gas flow path becomes a closed system so-called closed system circulation path. It is configured. Usually, air is used as the gas.

  In FIG. 1, the copper wire 1 introduced from the inlet 3 of the gas flow pipe 6 and led out from the outlet 4 is discharged and blown through the nozzle 5 in the gas flow pipe 6 between the inlet 3 and the outlet 4. The cleaning liquid adhering to the surface is removed by drying with the gas. In addition, the gas discharged and sprayed toward the copper wire 1 through the nozzle 5 in the gas flow pipe 6 is a gas that removes the cleaning liquid from the surface of the copper wire 1 and mists the removed cleaning liquid. The gas-liquid separator 7 is passed through. In the gas-liquid separator 7, the cleaning liquid is recovered by separating the mist from such a gas. Further, the gas that has passed through the gas-liquid separator 7 is sent to the gas flow pipe 6 through the pipe 9 by the pump 8 or the blower, so that the gas flow path constitutes a closed system of a closed system. . Therefore, in this embodiment, the metal member can be dried by effectively removing the cleaning liquid from the surface of the copper wire 1 in such a circulation path, and when an organic solvent is used as the cleaning liquid, The organic solvent can be recovered while suppressing the diffusion of the solvent into the atmosphere as much as possible.

  Further, as shown in FIG. 2, the nozzle 5 arranged inside the gas flow pipe 6 has a trumpet surface-like gas introduction part having an end portion that is closely joined to the inner wall of the gas flow pipe 6 at the preceding stage. 10 Therefore, in this embodiment, since the gas in the gas flow pipe 6 is guided by the gas introduction unit 10 without leakage and discharged through the nozzle 5, the wind speed of the gas discharged through the nozzle 5 is increased, The copper wire 1 can be effectively dried to sufficiently remove the cleaning liquid from the surface of the copper wire 1.

Example 1
Based on FIGS. 1 and 2, a copper wire was drawn at a drawing speed of 30 m / min with a drawing die (not shown) to obtain a copper wire 1 having a diameter of 3 mm, and then filled with xylene as a cleaning solution using an organic solvent. The copper wire 1 was passed through a cleaning tank (not shown) to clean the surface of the copper wire 1. Immediately thereafter, the copper wire 1 was passed through the drying device 2 of FIG. 1 to dry the copper wire 1 and remove the cleaning liquid from the surface of the copper wire 1. Thereafter, the copper wire 1 is guided to an annealing furnace (not shown) before the insulating paint is applied.

  Here, xylene, which is an organic solvent that is a cleaning liquid in the cleaning tank, adheres to the surface of the copper wire 1 by passing through the copper wire 1 and is taken out. On the other hand, in the drying device 2, xylene adhering to the surface of the copper wire 1 is dried by the gas discharged through the nozzle 5 in the process of passing through the gas flow pipe 6 and removed from the surface of the copper wire 1. Although some of them volatilize and leak from the inlet 3 and outlet 4 of the gas flow pipe 6, most of them are recovered by the gas-liquid separator 7. If the drying is not sufficient, xylene adhering to the surface of the copper wire 1 is brought into an annealing furnace and volatilizes there.

  The drying performance for the copper wire after being washed in the washing tank is as follows: the amount of xylene reduced (consumption) in the washing tank, the amount of xylene collected by the gas-liquid separator (recovery amount), and the annealing furnace. It can be determined comprehensively from the measured xylene concentration in the atmosphere. Here, Table 2 shows the results of comparing and comparing the drying performance for the same copper wire in each of the examples and comparative examples. In the comparative example, a conventional air blow method was adopted as a drying method, and there was no amount of xylene recovered.

  In Table 2, the original drying performance with respect to the copper wire after washing can be evaluated from the amount of xylene that is attached to the surface of the copper wire without being dried, and is evaluated from the xylene concentration in the atmosphere measured in the annealing furnace. can do. The xylene recovery performance can be evaluated from the amount of xylene recovered (recovery amount). In the example, 125 mL of 213 mL of xylene consumed in the washing tank is recovered by the gas-liquid separator, and the recovery rate of xylene is about 58%.

  In the embodiment, the cleaning liquid (organic solvent) adhering to the surface of the copper wire 1 is set by appropriately setting the flow rate of the gas discharged from the nozzle 5 toward the copper wire 1 according to the traveling speed of the copper wire 1. ) Is peeled off and removed by the gas and scattered as mist in the gas. Most of the mist is carried in the direction of the gas-liquid separator 7 by the gas flow, but a part of the mist remains inside the gas flow pipe 6. At this time, by appropriately controlling the pressure inside and outside the gas flow pipe 6, the amount of gas flowing out from the inlet 3 and the outlet 4 of the gas flow pipe 6 can be suppressed by the pressure difference. The amount of mist contained and leaked can be suppressed.

  Further, the gas containing the misted cleaning liquid (organic solvent) reaches the gas-liquid separator 7 by the flow, and the organic solvent is separated and recovered there. As the gas-liquid separator 7, an organic solvent is recovered using a mist trap made of resin fiber or glass wool, an organic solvent is recovered by a cyclone type apparatus using centrifugal force, and the cleaning liquid is condensed by cooling. There are devices that use capacitors that recover organic solvents, and can be selected as appropriate according to the type of organic solvent. In the case of cleaning liquids that use highly volatile organic solvents such as xylene, It is preferable to use a gas-liquid separator using a condenser, which can also recover the organic solvent evaporated. In the embodiment, a cyclone type gas-liquid separator 7 using centrifugal force is used.

(Example 2)
Another example of actual drying after washing will be described. Cleaning was performed in the same manner as in Example 1 except that an emulsion lubricant containing water as a main component was used as the cleaning liquid. The drying performance was evaluated by measuring the change in the weight of the cloth after placing the cloth on the surface of the copper wire and wiping it for a certain time. That is, first, when the gas flow pipe 6 of FIG. 2 is not provided, the amount W1 of water adhering to the copper wire surface is measured, and then when the gas flow pipe 6 of FIG. The amount W2 of water adhering to the copper wire surface after passing through the tube 6 was measured, and both were compared. As a result of the measurement, W1 = 4.1 g / min, W2 was below the measurement lower limit (measurement lower limit = 0.1 g / min), and it was confirmed that water was effectively peeled off.

Here, the proper gas flow rate necessary for peeling and removing the cleaning liquid adhering to the surface of the copper wire 1 and the capacity of the pump 8 or the blower necessary for generating it will be considered. As a result of the examination by the inventors, the flow rate necessary for peeling the cleaning liquid from the surface of the copper wire is 45 m / sec or more as shown in FIG. 3, and below that, for example, the gas flow pipe 6 is used. In this case, it was found that the cleaning liquid cannot be peeled off from the copper wire surface unless the gas flow pipe 6 is passed a plurality of times. In FIG. 3, when the inner diameter of the nozzle 5 is 5 mm, the flow rate of gas necessary to achieve a flow rate of 45 m / sec is about 53 L / min, and the inner diameter of the gas flow pipe 6 arranged almost vertically is 20 mm. If the length is 1 m, the pressure difference between the gas at both ends of the gas flow pipe 6 is about 12 Pa. As the capacity of the pump 8 or the blower necessary for obtaining such a flow velocity and pressure difference (static pressure), a small turbo fan is sufficient. For example, a turbo fan T2-1010014 of Rokugo Seisakusho can generate a pressure of 135 Pa at a flow rate of 0.1 m ³ / min when the rotational speed is 3000 rpm, and can be used sufficiently.

DESCRIPTION OF SYMBOLS 1 Copper wire 2 Drying apparatus 3 Inlet 4 Outlet 5 Nozzle 6 Gas distribution pipe 7 Gas-liquid separator 8 Pump 9 Piping 10 Gas introduction part

Claims (6)

  A metal member cleaning method for cleaning a metal member surface with a cleaning liquid and then drying the metal member to remove the cleaning liquid from the surface of the metal member. A gas flow pipe in which a nozzle is arranged so that gas therein is discharged toward a metal member passing between the inlet and the outlet, a gas-liquid separator, and a pump or blower are connected by a pipe, A method for cleaning a metal member, wherein the metal member is dried using a drying device configured such that the gas circulation path is a closed circulation path.   The method for cleaning a metal member according to claim 1, wherein the nozzle has a gas introduction portion that is closely joined to an inner wall of the gas flow pipe at a preceding stage.   The method for cleaning a metal member according to claim 1 or 2, wherein a flow rate of the gas discharged through the nozzle is 45 m / sec or more.   A metal member cleaning apparatus for cleaning a surface of a metal member with a cleaning liquid and then drying the metal member to remove the cleaning liquid from the surface of the metal member. A gas flow pipe in which a nozzle is arranged so that gas therein is discharged toward a metal member passing between the inlet and the outlet, a gas-liquid separator, and a pump or blower are connected by a pipe, An apparatus for cleaning a metal member, comprising: a drying device configured such that the gas circulation path is a closed circulation path.   The metal member cleaning apparatus according to claim 4, wherein the nozzle has a gas introduction portion that is closely joined to an inner wall of the gas flow pipe in a preceding stage.   The metal member cleaning apparatus according to claim 4 or 5, wherein a flow rate of the gas discharged through the nozzle is 45 m / sec or more.

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