JPH0131945B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for preventing sagging marks in spray-type coil surface treatment. More specifically, in a unique situation in coil surface treatment operations, when the conveyance speed is reduced when the coil passes through the spliced area, and the surface treatment is partially interrupted, there is The purpose is to prevent drip marks from being formed on the surface due to falling droplets.

In general, spray-type coil surface treatments (e.g. chemical conversion treatment, degreasing treatment, etching treatment) are
The present invention is also implemented in an apparatus having the structure shown in FIGS. In the figure, 1 is a processing plate, 2 is a pump,
3 is a squeeze roll, 4 is a booth chamber, 5 is a surface treatment liquid tank, 6 is an upper spray riser, 7
is the lower spray riser, 8 is the spray nozzle,
9 is a surface treatment liquid return port, 10 is a booth chamber ceiling cover, and 11 is a spray group switching valve.

During surface treatment in equipment with such a configuration, the conveyance speed of the coil is generally reduced as the plate-spliced portion of the coil passes through the equipment (this tendency is more necessary for high-speed processing lines). ). In order to control the surface treatment amount in accordance with this decrease, the application of the surface treatment liquid by the spray group is performed at the switching valve 11 in order to keep the treatment time constant.
The processing plates are stopped sequentially from the entrance side to the apparatus. (Generally, the above application is not stopped in the rearmost zone from the inlet side.) After passing through the plate joint, the coil conveyance speed is increased to a predetermined speed, and at the same time, the spray group switching valve 11 is also set in the forward dimension from the outlet side of the device. will be returned to. In this way, in the spray zone where the application of the surface treatment liquid is stopped when the board joint passes through the equipment, when droplets fall from various parts of the equipment onto the treated board, they remain on the surface of the treated board as sagging marks, and the product is damaged. decrease the value. This inevitably occurs because excess surface treatment liquid is removed by the squeezing roll 3 at the entrance and exit of each zone. In order to prevent such drip marks from occurring, conventional methods have been to place the upper spray riser 6 outside the processing plate or to tilt the ceiling cover 10, but this prevents droplets from forming on the processing plate. It was not possible to sufficiently prevent falls, and as a result, approximately 20
This resulted in surface treatment defects of around 30%.

The present invention solves the problems of the prior art, and its gist is that the coil is passed through a plurality of continuous zones each having a squeezing roll at the entrance and exit, and a surface treatment liquid is sprayed onto the coil in the zones. A method for preventing sagging marks on a coil surface, characterized in that the coil is placed in a zone where the application of surface treatment is stopped, and water is sprayed onto the coil during the stop period.

Next, the present invention will be specifically explained with reference to the accompanying drawings FIGS. 3 and 4. In the figure, reference numeral 12 indicates a washing water spray nozzle, and reference numeral 13 indicates a spray group switching valve thereof.Those having the same numbers as in FIGS. 1 and 2 have the same meaning.

That is, in each spray zone of the booth chamber 4, a washing water spray nozzle 12 is arranged especially on the inlet side, and a switching valve 13 attached to each nozzle is arranged.
is linked to each switching valve 11 of the surface treatment liquid, and at the same time as the switching valve 11 is closed or opened, or just before that.
Immediately after, the switching valve 13 is opened or closed.
In addition, in the rearmost zone, it is generally not necessary to provide the nozzle 12 described above. Therefore, in the spray zone where the application of the surface treatment liquid to the treated plate is stopped, washing water is sprayed onto the treated plate to wet and protect the surface, so that droplets do not fall on the surface. However, no sagging marks will be formed. On the other hand, when the application of the surface treatment liquid is restarted, the application of the rinsing water spray is stopped, so that the predetermined surface treatment can be performed without any problem. Note that, although fresh water may be used as the washing water, surplus water in the washing step, which is the next step in surface treatment, may be used.

In the present invention, in order to more effectively wet the surface of the processing plate with the rinsing water spray, the processing plate is tilted downward from the inlet side to the outlet side of the apparatus, as shown in FIG. It is advantageous to transport the Further, in order to prevent droplets from falling onto the processing plate as much as possible, the booth chamber ceiling cover 10 may be tilted in one direction as shown in FIG.

According to the above configuration, even if droplets fall onto the processing plate when surface treatment is partially stopped, it is possible to prevent drip marks from occurring.

[Brief explanation of drawings]

Fig. 1 is a side sectional view showing an example of a conventional apparatus for performing spray-type coil surface treatment, Fig. 2 is a front sectional view thereof, and Fig. 3 is a side sectional view showing an example of an apparatus for carrying out the method of the present invention. Figure 4 is a front sectional view of the same, in which 1 is a processing plate, 3 is a squeeze roll,
4 is a booth chamber, 6 is an upper spray riser, 7 is a lower spray riser, 8 is a spray nozzle, 10 is a booth chamber ceiling cover, 11 is a switching valve, 12 is a washing water spray nozzle, and 13 is the switching valve. .

Claims (1)

[Scope of Claims] 1. A method in which a coil is passed through a plurality of consecutive zones each having a squeezing roll provided at an entrance and exit, and a surface treatment liquid is applied to the coil by spraying in the zones, in which the application of the surface treatment is stopped. A method for preventing sagging marks on a coil surface, characterized by spraying water on the coil during the stop period in a zone where the coil is stopped. 2. As the coil conveyance speed is reduced, the application of the surface treatment liquid in continuous zones is stopped sequentially from the coil inlet side except for the rearmost zone from the coil inlet side, and as the coil conveyance speed is restored, the surface treatment liquid is applied to the surface treatment liquid in continuous zones. In a treatment method in which the application of the treatment liquid is restarted sequentially from the zones starting from the coil outlet side, the application of water in the corresponding zones is carried out according to the order in which the application of the surface treatment liquid is stopped, and the application of water is carried out in the corresponding zones according to the order in which the application of the surface treatment liquid is restarted. The method of paragraph 1 above, wherein the application of water in the zone is stopped. 3. The method according to item 2 above, in which the coil is conveyed in a downwardly inclined state from the entrance side to the exit side of the continuous zone of the coil.