JPS6120035Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a continuous electroplating apparatus for steel strips, and more particularly to a continuous electroplating apparatus for steel strips that can prevent washing water from flowing into a plating tank.

The arrangement before and after the plating tank of the continuous electroplating apparatus for steel strips is shown in FIGS. 1 and 2. FIG. 1 shows a general horizontal plating device, which is composed of a master plating tank 2 and a sub-plating tank 4. A steel strip 6 is energized by a conductor roll 8 and a back-up roll 10, and is energized by a dam roll 12. Plating is performed in the secondary plating tank 4 in which the liquid level is maintained.Finally, the adhering plating liquid is removed at the outlet by a squeezing roll 14, and then washed by a washing water spray device 16.

On the other hand, in the vertical type apparatus shown in FIG. 2, the plating tank 18 is vertical, and the steel strip 6 is immersed in the plating tank 18 by a date roll 20 to be plated, as in the horizontal type. Squeezing roll 1 at the exit
After the plating liquid is removed by step 4, it is cleaned by a cleaning water spray device 16.

In general, in continuous electroplating equipment for steel strips, controlling the concentration and volume of the plating solution is an important item.

Let's consider the concentration and volume of the plating solution using electrogalvanizing equipment as an example. The balance of the plating solution that uses metallic zinc for the anode progresses as shown in Figure 3.
The concentration of the plating solution becomes thinner due to the removal of the solution that adheres to the front and back surfaces of the steel strip. That is, the cleaning water for pickling in the plating pretreatment flows into the plating tank from the inlet side, adhering to the steel strip, and the plating solution flows out from the plating tank, adhering to the steel strip.

In galvanizing, zinc is the standard for plating solution concentration and usually has a cathode efficiency of 93-97% and 100-105%.
Due to the difference in anode efficiency, zinc remains in the plating solution and plays a role in increasing the concentration.

On the other hand, the amount of plating solution may evaporate and scatter a little, but if it is only the inflow and outflow as described above, there will be almost no quantitative change, and the zinc or sulfuric acid bath system will compensate for the lack of concentration increase due to the difference in cathode and anode efficiency. ZnSO ₄ or ZnCl ₂ may be added in the case of a chloride bath system.

However, in actual operations, unlike the plating liquid balance shown in Fig. 3, it is customary to use washing water immediately after exiting the plating tank in order to make the appearance of the plated surface of the steel strip beautiful. When this flows into the plating tank, it causes a decrease in the concentration of the plating solution and an increase in the amount of the plating solution more than necessary, which is considered a problem.

Although it is preferable to use more washing water in order to improve the appearance of the product during operation, in order to avoid a decrease in the concentration of the plating solution and an increase in the amount of solution, the amount of washing water used is generally reduced. As a result, the appearance of the plated surface is uneven.

The washing water on the outlet side of the plating tank flows into the plating tank due to the rotation of the squeezing roll 14, as shown in FIG.
There is little inflow from the lower squeezing roll 14B. Conventionally, a plate-shaped rubber seal was provided on the surface of the upper squeezing roll 14A to prevent liquid from flowing in from the upper squeezing roll 14A, but when the line speed exceeded 70 m/min, the vibration of the rubber seal was severe and the liquid draining effect was not improved. Ta.

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the prior art described above and to provide a continuous electroplating apparatus for steel strips that can prevent cleaning water adhering to the steel strips from flowing into the plating tank.

The main points of this invention are as follows. That is, a plating bath for continuously electroplating the steel strip, a conductor roll provided on both sides of the plating bath for energizing the steel strip, and a conductor roll provided on the final exit side of the conductor roll for electroplating the steel strip. A continuous electroplating apparatus for steel strips, comprising a squeeze roll for removing a plating liquid, and a cleaning water spray device installed immediately after the squeeze roll for cleaning the surface of the plated steel strip, The apparatus for continuous electroplating of steel strips is characterized in that it has a touch roll which is provided parallel to and in contact with the upper part of the squeezing roll and discharges washing water adhering to the steel strip to the outside of the plating tank.

The details of the present invention will be explained with reference to an embodiment of a horizontal plating tank. In FIG. 5, the arrangement of the parent mating tank 2, secondary mating tank 4, conductor roll 8, back-up roll 10, dam roll 12, squeezing roll 14, cleaning water spray device 16, etc. is the same as that of the conventional one.
Although it is similar to the figure, a zinc anode 22 is shown inside the plating tank 4. Further, a tatsuchi roll 24, which is a feature of the present invention, was provided in contact with and parallel to the upper part of the upper drawing roll 14A. As shown in FIG. 6, the touch roll 24 was mounted parallel to and in contact with the upper drawing roll 14A by means of a roll support frame 26. As shown in FIG. 7, the Tatsuchi Roll 24 covers the outside of the covered rubber support ring 28 with a covered rubber 30, and has a length of 1800 mm.
The outer diameter is 150mm. It should be noted that a rubber seal piece 32 for drainage, which is attached to the plating tank wall in the conventional manner, is in contact with the lower surface of the lower squeezing roll 14B.

The effects of the embodiment of the continuous plating apparatus of the present invention having the above structure will be explained. steel strip 6
When the sheet is threaded at a line speed of 100 m/min, the rotation of the upper drawing roll 14A also rotates the Tatsuchi roll 24. The cleaning water from the cleaning water spray device 16 is lifted from the upper surface of the steel strip 6 by the rotation of the upper squeezing roll 14A, then squeezed by the touch roll 24, and falls out of the plating tank.

On the other hand, the cleaning water naturally falls on the lower surface of the steel strip 6, but the cleaning water adhering to the lower squeezing roll 14B is squeezed out by the rubber seal piece 32 provided on the lower surface of the lower squeezing roll 14B, and is squeezed into the plating tank. fall outside.

In this example, even if a large amount of water is used for cleaning, it is possible to prevent the cleaning water from mixing with the plating solution, thereby preventing the occurrence of unevenness on the plated surface, and preventing the plating solution from mixing with the cleaning water into the plating solution. It was possible to prevent a decrease in the concentration and an increase in the amount of

As is clear from the above embodiments, the present invention improves the surface appearance of the plated surface through sufficient cleaning by installing a tatsuchi roll on top of the squeezing roll to prevent washing water from flowing into the plating tank. This has the effect of making liquid management easier.

[Brief explanation of the drawing]

Figure 1 is a layout diagram showing a conventional horizontal continuous plating device, Figure 2 is a layout diagram showing a conventional vertical continuous plating device, and Figure 3 is a plating solution when using metallic zinc for the anode. 4 is a cross-sectional view showing the relationship between a conventional squeezing roll and a cleaning water spray device, FIG. 5 is a partial sectional view showing the continuous electroplating device of the present invention, and FIG. 6 is a schematic diagram showing the balance of FIG. 7 is a side view showing the attachment of the Tatsuchi Roll of the present invention, and a perspective view showing the configuration of the Tatsuchi Roll of the present invention. 2... parent mating tank, 4... child mating tank, 6...
Steel strip, 8... Conductor roll, 14, 14
A, 14B... Squeezing roll, 16... Washing water spray device, 18... Plating tank, 24... Tatsuchi roll.

Claims (1)

[Scope of utility model registration request] a plating bath for continuously electroplating the steel strip; a conductor roll provided on both sides of the plating bath for energizing the steel strip; and a plating provided on the final exit side of the conductor roll for adhering to the steel strip. A continuous electroplating apparatus for steel strips, comprising: a squeeze roll for removing liquid; and a cleaning water spray device installed immediately after the squeeze roll for cleaning the surface of the plated steel strip. 1. An apparatus for continuous electroplating of steel strips, comprising a tatsuchi roll that is provided parallel to and in contact with the upper part of the rolls and discharges washing water adhering to the steel strips to the outside of the plating tank.