JP2011174109A - Surface treatment apparatus and surface treatment method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress generation of dew condensation above a workpiece when executing the surface treatment by blowing treatment liquid to the workpiece. <P>SOLUTION: The surface treatment of a workpiece 3 is executed by blowing treatment liquid 6 toward the workpiece 3 conveyed in a treatment tank 1. A ceiling surface heating device 12 for heating a lower surface (ceiling surface) of a tank cover 7 located above the workpiece 3 in the treatment tank 1 is provided, and the temperature of the ceiling surface is adjusted equal to or higher than the temperature of the treatment liquid 6 by the ceiling surface heating device 12. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a surface treatment technique including a step of spraying a treatment liquid toward a material to be treated in a treatment tank, such as applying a treatment liquid by spraying a chromate treatment liquid or the like to a steel material and performing a chemical conversion treatment.

  As a surface treatment facility having a step of continuously applying a treatment liquid to a steel material that is continuously conveyed, for example, there is a facility described in Patent Document 1. In the facility described in Patent Document 1, a hood is disposed above a steel material to be surface-treated. And when external temperature is low, the vapor | steam of a process liquid may condense on the food | hood inner surface, and there exists a possibility that the condensed droplet may fall to the steel material in process.

  On the other hand, in patent document 1, in order to prevent the droplets adhering to the inner surface of the hood from falling on the steel material being processed, water is sprayed on the inner surface of the hood to cause condensation on the inner surface of the hood. It has been proposed to remove and clean existing droplets.

JP 2000-96275 A

The above prior art is configured to remove water droplets by spraying the droplets on the premise that the droplets are condensed on the inner surface of the hood. Therefore, condensation on the inner surface of the hood cannot be suppressed.
The present invention has been made paying attention to the above points, and it is an object of the present invention to suppress the occurrence of dew condensation above the material to be treated when a surface treatment is performed by spraying a treatment liquid onto the material to be treated. .

In order to solve the above-mentioned problems, the invention described in claim 1 of the present invention is a surface treatment for performing a surface treatment of a material to be treated by spraying a treatment liquid toward the material to be treated conveyed into the treatment tank. In equipment,
A heating device for heating a ceiling surface located above the material to be processed in the processing tank is provided, and the ceiling surface is adjusted to be equal to or higher than the temperature of the processing liquid by the heating device.

Next, in the invention described in claim 2, in the configuration described in claim 1, the heating device is configured to process the inside of a pipe line disposed along a ceiling plate member forming a ceiling surface of the processing tank. The ceiling surface is heated by circulating a liquid having a temperature equal to or higher than the temperature of the liquid.
Next, the invention described in claim 3 is characterized in that the surface treatment is a chemical conversion treatment of a steel material with respect to the configuration described in claim 1 or claim 2.

Next, the invention described in claim 4 is a surface treatment method for performing a surface treatment of the material to be treated by spraying a treatment liquid toward the material to be treated conveyed into the treatment tank.
The treatment liquid is sprayed while the ceiling surface located above the material to be treated in the treatment tank is adjusted to a temperature equal to or higher than the temperature of the treatment liquid.

ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to suppress the dew condensation on the ceiling surface located above a to-be-processed material by adjusting a ceiling surface more than the temperature of a process liquid. As a result, it is possible to suppress the drop of droplets on the material to be processed.
At this time, according to the second aspect of the invention, it is possible to stably heat the ceiling surface to a target temperature.

  Further, by targeting the chemical conversion treatment equipment, it is possible to prevent the occurrence of defects in chemical conversion treatment due to the fall of condensed droplets onto the material to be processed.

It is a schematic diagram for demonstrating the chemical conversion treatment equipment which concerns on embodiment based on this invention. It is a figure for demonstrating the heating apparatus which heats the tank cover which concerns on embodiment based on this invention. It is a figure which shows the relationship between tank cover temperature and the number of nonuniformity after process liquid application.

Next, embodiments of the present invention will be described with reference to the drawings.
In the present embodiment, a chemical conversion treatment facility using a steel plate as the material to be treated will be described as an example of the surface treatment facility.
FIG. 1 is a schematic diagram showing a chemical conversion treatment facility as a surface treatment facility of the present embodiment.

(Constitution)
The chemical conversion treatment facility of the present embodiment is a horizontal treatment facility that applies a treatment liquid while conveying a material to be treated along a horizontal direction or a substantially horizontal direction.
As shown in FIG. 1, the chemical conversion treatment facility according to the present embodiment includes a processing tank 1 (only one processing tank 1 is illustrated in FIG. 1) that constitutes one or two or more processing tanks, and a target. And a dryer facility 2 for drying the treatment liquid applied to the surface of the treatment material 3. And the to-be-processed material 3 is continuously conveyed along the conveyance line prescribed | regulated previously, and the coating process of a process liquid is implemented in the said processing tank 1 sequentially.

Here, the said to-be-processed material 3 is a steel plate, for example.
In the processing tank 1, a spray header 4 and two pairs of ringer rolls 5 disposed above and below the material to be processed 3 are disposed.
The spray header 4 is formed with a plurality of spray ports 4a, and the spray ports 4a are arranged so that a treatment liquid 6 such as a chromate treatment liquid can be sprayed from the spray ports 4a toward the surface of the material 3 to be treated. ing. That is, the treatment liquid 6 can be applied to the entire surface of the material to be treated 3 by ejecting the treatment liquid 6 from the plurality of injection ports 4a.

The ringer rolls 5 are respectively arranged on the inlet side and the outlet side in the processing tank 1 to squeeze the processing liquid 6 applied to the surface of the material 3 to be processed.
The processing tank 1 has a tank cover 7 that faces the material 3 to be processed in the vertical direction. The tank cover 7 constitutes a ceiling plate member, and the lower surface of the tank cover 7 forms a ceiling surface. In addition, when arrange | positioning a hood between the tank cover 7 and the to-be-processed material 3, a hood lower surface comprises a ceiling surface.

  Further, the bottom surface 1 a of the processing tank 1 has a hopper shape capable of collecting the falling processing liquid 6, and the processing liquid 6 that has dropped on the bottom surface 1 a of the processing tank 1 passes through the processing liquid recovery path 8. Returned to tank 9. The processing liquid 6 in the processing liquid tank 9 is heated by the heating device 10 and stirred by the stirring device 11 so as to reach a predetermined temperature. The processing liquid 6 in the processing liquid tank 9 is circulated by being supplied to the spray header 4 through the processing liquid feed path 25.

In the said embodiment, the ceiling surface heating apparatus 12 which heats the said tank cover 7 is provided. The ceiling surface heating device 12 is a device that adjusts the lower surface of the tank cover 7 serving as the ceiling surface to be equal to or higher than the temperature of the processing liquid 6 according to a command from the ceiling surface controller 13.
As shown in FIG. 2, the ceiling surface heating device 12 of the present embodiment includes a first thermometer 18 that measures the temperature of the heating conduit 14, the heating circulation tank 15, and the tank cover 7.

  The heating conduit 14 is laid on the upper surface of the tank cover 7. Specifically, the heating conduit 14 is laid so as to meander along the upper surface of the tank cover 7 so that the entire surface of the tank cover 7 can be heated and kept warm. Both ends of the heating conduit 14 are connected to the heating circulation tank 15 so that the liquid 22 in the heating circulation tank 15 can circulate through the heating conduit 14. A pump 16 is interposed on one end side of the heating conduit 14, and the liquid 22 can be pumped to the heating conduit 14 by driving the pump 16. That is, by driving the pump 16, the liquid 22 in the heating circulation tank 15 flows continuously in the heating pipe line 14. The liquid 22 in the heating circulation tank 15 can be heated by the temperature raising device 17. The temperature raising device 17 may be provided in the heating circulation tank 15 or may be interposed in the heating conduit 14.

Here, the liquid 22 may use hot water, for example.
The first thermometer 18 measures the temperature of the tank cover 7 and outputs it to the ceiling surface controller 13. The second thermometer 19 measures the temperature of the liquid 22 in the heating circulation tank 15 and outputs the measured value to the ceiling surface controller 13.
Further, the temperature of the processing liquid 6 in the processing tank 1 measured by the third thermometer 20 is input to the ceiling surface controller 13. The temperature of the processing liquid 6 may be a target management temperature of the processing liquid 6.

  The ceiling surface controller 13 sets a temperature equal to or higher than the temperature of the processing liquid 6 to the target temperature based on the input temperature of the processing liquid 6. And the ceiling surface controller 13 is based on the temperature information from the said 1st thermometer 18 in the state which hold | maintained the temperature of the liquid 22 in the circulation tank 15 for a heating in the temperature higher than the temperature of the process liquid 6, for example. The pumping amount of the pump 16 (that is, the flow velocity of the liquid 22 flowing through the heating pipe 14) is controlled so that the temperature of the tank cover 7 becomes equal to or higher than the target temperature. Or, based on the temperature information from the first thermometer 18, the liquid 22 is heated by the temperature raising device 17 so that the temperature of the tank cover 7 becomes equal to or higher than the target temperature so that the temperature of the tank cover 7 becomes the target temperature. Perform feedback control. Here, in consideration of a control error, the target temperature may be set high by a predetermined margin.

Before starting the chemical conversion treatment, the temperature of the tank cover 7 is adjusted in advance to be equal to or higher than the temperature of the treatment liquid 6.
Here, when the chemical conversion treatment was performed by changing the temperature of the tank cover 7 with respect to the liquid temperature of the treatment liquid 6, the number of unevenness generated in the steel plate (material 3) after the chemical conversion treatment was measured. . Experiments were individually performed at three temperatures of 30 ° C., 35 ° C., and 40 ° C. as the liquid temperature of the treatment liquid 6. FIG. 3 shows the result.

  As can be seen from FIG. 3, when the liquid temperature of the processing liquid 6 is 30 ° C. or 35 ° C., the temperature of the tank cover 7 is adjusted to the same temperature as the liquid temperature of the processing liquid 6, thereby dropping droplets. It can be seen that the occurrence of unevenness can be suppressed to zero. Further, when the liquid temperature of the treatment liquid 6 is 40 ° C., by adjusting the temperature of the tank cover 7 to the same temperature as the treatment liquid 6, the occurrence of unevenness due to the drop of droplets can be significantly suppressed. It can be seen that by setting the temperature of the processing liquid 6 higher by 5 ° C. or more than the liquid temperature, the occurrence of unevenness due to the dropping of the droplets can be suppressed to zero.

From the above, it is preferable to set the temperature of the tank cover 7 higher than the temperature of the processing liquid 6 by 5 ° C. or more.
Here, when the normal chemical conversion treatment for the steel sheet is considered, when the liquid temperature of the treatment liquid 6 is lower than 30 ° C., the reaction of the chemical conversion treatment tends to deteriorate. Moreover, when the liquid temperature of the process liquid 6 exceeds 40 degreeC, it exists in the tendency for the adhesion amount of the process liquid 6 to be too much. Therefore, the treatment liquid 6 is normally managed at about 30 ° C. to 40 ° C.

(Action, effect, etc.)
In the present embodiment, the material 3 such as a steel plate is continuously conveyed to the processing tank 1, and the processing liquid 6 having a target management temperature is applied to the surface of the material 3 by spraying in the processing tank 1, By squeezing the processing liquid 6 applied by the ringer roll 5, a predetermined amount of the processing liquid 6 is applied to the surface of the material 3 to be processed.

  At this time, a part of the processing liquid 6 evaporates in the processing tank 1, but since the temperature of the tank cover 7 is equal to or higher than the temperature of the processing liquid 6, the processing liquid 6 may be condensed on the lower surface of the tank cover 7. Is prevented. As a result, it is possible to prevent droplets due to condensation from falling on the material 3 to be processed, that is, to prevent processing unevenness on the material 3 to be processed. In particular, by adjusting the temperature of the tank cover 7 to 5 ° C. or higher than that of the processing liquid 6, it is possible to eliminate the processing unevenness of the processing target material 3 due to the drop of the liquid droplet (see FIG. 3).

Although there is a possibility that condensation occurs on the side wall surface in the processing tank 1, the droplets due to condensation flow downward along the side wall surface, so that they do not fall on the material 3 to be processed.
Here, as a solution for suppressing the condensation on the tank cover 7, a method of reducing the amount of condensation on the ceiling surface by lowering the temperature of the treatment liquid 6 can be considered. However, in this method, there is a possibility that the reactivity of the treatment liquid 6 is inhibited and the corrosion resistance is deteriorated.

On the other hand, in this embodiment, since it is not necessary to lower the temperature of the treatment liquid 6, the above-described adverse effect on the chemical conversion treatment can be suppressed.
Here, although the case where the liquid 22 such as hot water is circulated as the ceiling surface heating device 12 to heat the tank cover 7 is illustrated in the above embodiment, the ceiling heating device is not limited to this. You may make it adjust the temperature of the tank cover 7 more than the temperature of the process liquid 6 with other heat generation mechanisms, such as a heating wire. Or you may make it adjust the temperature of the tank cover 7 more than the temperature of the process liquid 6 by spraying the warm air of the temperature more than the process liquid 6 on the tank cover 7. FIG. The method of circulating and heating the liquid 22 such as warm water is suitable when the temperature of the tank cover 7 is stably adjusted to the target temperature state.

  Moreover, in the said embodiment, although the chemical conversion treatment was illustrated as surface treatment, processing liquid which performs processing by spraying or dripping the processing liquid 6, such as cleaning processing equipment, such as pickling processing equipment, is applied to the ceiling. The present embodiment can be applied to any surface treatment that may cause condensation.

DESCRIPTION OF SYMBOLS 1 Processing tank 3 To-be-processed material 4 Spray header 4a Spray outlet 5 Ringer roll 6 Processing liquid 7 Tank cover (ceiling board member)
DESCRIPTION OF SYMBOLS 12 Ceiling surface heating apparatus 12 Ceiling surface heating apparatus 13 Ceiling surface controller 14 Heating pipe line 15 Heating circulation tank 16 Pump 17 Temperature rising device 18 First thermometer 19 Second thermometer 20 Third thermometer

Claims (4)

In the surface treatment equipment for performing the surface treatment of the material to be treated by spraying the treatment liquid toward the material to be treated conveyed into the treatment tank,
A surface treatment facility comprising a heating device for heating a ceiling surface located above the material to be treated in the treatment tank, wherein the ceiling surface is adjusted to a temperature equal to or higher than the temperature of the treatment liquid by the heating device.   The heating apparatus heats the ceiling surface by circulating a liquid having a temperature equal to or higher than the temperature of the processing liquid in a pipe line disposed along a ceiling plate member that forms the ceiling surface of the processing tank. The surface treatment facility according to claim 1.   The surface treatment facility according to claim 1, wherein the surface treatment is a chemical conversion treatment of a steel material. In the surface treatment method for performing the surface treatment of the material to be treated by spraying the treatment liquid toward the material to be treated conveyed into the treatment tank,
A surface treatment method comprising spraying the treatment liquid while adjusting a ceiling surface located above the material to be treated in the treatment tank to a temperature equal to or higher than the temperature of the treatment liquid.

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