JPS61190094A - Electroplating installation - Google Patents

Abstract

PURPOSE:To suppress the oscillation and camber of a steel strip traveling in a vertical direction and to reduce electric power for plating by placing rectangular anode plates on both sides of the steel strip, disposing static pressure pads for ejecting a plating liquid to the central part thereof and providing insulating edge masks to cover both ends of the strip. CONSTITUTION:The steel strip S is vertically run by conductor rolls 31, 32 in a plating cell 1. The strip S passes between the rectangular late-shaped anodes 5 consisting of upper electrodes 6 and lower electrodes 7. The plating liquid is ejected to the steel strip from ejection ports 12 facing the upward and horizontal directions of the static pressure pads 11 provided between the electrodes 6 and 7. The static pressure is generated on both sides of the steel strip by such injection, by which the camber and oscillation of the steel strip are prevented. The electrically insulating edge masks 35 to cover both ends of the steel strip are disposed to the part of the anodes 5 by which the spreading of the plating to said parts is prevented and the spacing between the steel strip and the anodes 5 is decreased. The electric power for plating is thus reduced.

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention is based on electroplating! ! It concerns an installation, in particular an installation for continuous electroplating on one or both sides of a vertically running metal strip.

The invention is applied, for example, to equipment for electrodepositing zinc, soot, nickel, etc. on one or both sides of a copper strip.

(Prior Art) As a method of electroplating one or both sides of a strip, there is a method of continuously electroplating while running the strip in a vertical direction. In so-called vertical electroplating equipment that performs this type of electroplating, a pair of plate-shaped electrodes (anodes) are placed in a plating solution tank and face each other with their electrode surfaces perpendicular. Conductor rolls are arranged below and below, respectively. A plating solution is supplied between the electrodes. Plating is carried out by passing a strip (cathode) guided by a conductor roll between the electrodes. The plating solution is supplied between the electrodes using a plating solution supply device or by immersing the electrodes in the plating solution.

An example of such equipment is an electroplating equipment disclosed in Japanese Patent Application No. 59-89792.

(Problems to be Solved by the Invention) By the way, the conventional vertical electroplating apparatus has the following problems.

Generally, a strip has a warp in its width direction, and when the strip is run at high speed to increase productivity, the strip vibrates in a direction perpendicular to the plate surface. Therefore, in order to avoid contact between the strip and the electrode, it is necessary to increase the distance between the electrodes. As a result, the electrical resistance due to the plating solution between the electrode and the strip increases, resulting in increased power consumption. Furthermore, a large amount of plating solution must be supplied between the electrodes, requiring a large-capacity plating solution circulation pump.

Furthermore, due to the warpage in the width direction of the strip, the distance between the strip surface and the electrode surface is not uniform, resulting in uneven plating.

Furthermore, in the case of single-sided plating, conventional vertical electroplating equipment has the problem that the plating wraps around the side edges of the non-plated surface.

(Means for Solving the Problems) The electroplating equipment of the present invention includes a plating solution tank, a pair of opposing plate-shaped electrodes arranged in the plating solution tank with the plate surfaces vertical, and It consists of conductor rolls and a plating solution supply device, which are arranged below. The space between the electrodes is a plating chamber.

A pair of static pressure pads facing each other are provided approximately at the center of the electrode in the vertical direction. The static pressure pad is equipped with a plating solution spout opening toward the strip surface, and is connected to the plating solution supply device.

Further, an electrically insulating edge mask that covers the side end portions of the strip between the electrodes is provided so as to be movable in and out in the width direction of the strip.

(Function) The plating solution ejected from the static pressure pad generates static pressure on both sides of the strip in the vicinity of the static pressure pad. Therefore, the warpage of the strip surface is corrected by this static pressure. Further, the strip is held by static pressure near the static pressure pad, and vibration of the strip is prevented.

When performing single-sided plating, voltage is applied only to the electrode facing the surface to be plated. The edge mask is adjusted to cover both ends of the strip.Since both ends are covered by the edge mask, sufficient current does not flow to form the plating on the side edges of the non-plated surface. Therefore, the plating does not run into this part.

(Example) FIG. 1 shows an example of the present invention, and is a longitudinal sectional view of a vertical electroplating equipment.

As shown in the drawing, the vertical electroplating equipment mainly consists of a plating solution tank 1. - a set of rectangular plate electrodes5. Static pressure pad 11.
Conductor rolls 31, 32, plating solution supply device 2
0.22 and an edge mask 35.

The plating solution tank 1 consists of a container that opens upward. The plating solution tank 1 collects the plating solution E flowing down from the upper plating chamber 18 at the bottom.

The electrode 5 is an insoluble upper electrode 6 and a lower electrode 7 in the shape of a rectangular plate.
It is composed of. The upper electrode 6 and the lower electrode 7 each consist of a pair whose plate surfaces face each other, and are supported in the plating solution tank 1 with an interval above and below and with the plate surfaces perpendicular to each other. The electrode 5 is connected to a feeding conductive band (not shown).

It is maintained at a positive potential with respect to the strip S.

The static pressure pad 11 consists of a pair facing each other, and the upper electrode 6
and the lower electrode 7. The static pressure pad 11 is equipped with a plating solution spout 12 that opens toward the strip surface. As shown in Fig. 2, the plating solution spout 12 has two horizontal slits vertically spaced apart) 13.14
(4 vertical slits spaced horizontally) 15.1
It consists of 8. Further, as shown in FIG. 1, the upper horizontal slit 13 opens upward, and the lower horizontal slit 14 opens horizontally. The width of these slits is about a few seals. In addition, static pressure pad 1
1 is connected to a plating solution supply header 20.

A plating chamber 18 is formed by the electrode 5 and the static pressure pad 11.

A pair of plating solution auxiliary supply headers 22 are arranged directly above the electrodes 5 . Each plating solution auxiliary supply header 2
2 is equipped with a nozzle 23 directed toward the plating chamber 18.

Further, a liquid shut-off device 9 is attached to the lower end of the electrode 5 and includes a shut-off plate that can be moved in and out. The liquid shut-off device M9 adjusts the opening at the lower end of the plating chamber 18 with a shut-off plate,
A plating solution circulation pipe 25 is connected to the bottom of the plating solution tank 1, which adjusts the amount of plating solution E flowing out from the plating chamber 1B. Circulation pump 2
6 supplies plating solution E.

Six conductor rolls 31 with conductor rolls 31 and 32 arranged above and below the electrodes 5, respectively.
, 32 guide the strip S so that it runs while keeping a constant distance between it and the electrode 5.

Strip S in contact with conductor rolls 31, 32
is maintained at a negative potential with respect to the electrode 5.

As shown in FIGS. 2 and 3, a pair of edge masks 35 made of an electrically insulating material are provided between the electrodes 5 so as to be movable in and out. The edge mask 35 has a U-shaped cross section so as to cover the side edge of the strip S.
It extends vertically to almost the full length of the electrode 5.

A drive rod 37 passing through the side wall 3 of the plating solution tank 1 is connected to the back of the edge mask 35. The drive rod 37 advances and retreats from the edge mask 35 by a drive device (not shown) such as a hydraulic cylinder connected thereto.

A rubber shielding sheet 3 is attached to the back of the edge mask 35.
One end of the shielding sheet 38 is fixed, and the other end of the shielding sheet 38 is fixed to the inner surface of the side wall 3 of the plating solution tank l. The shielding sheet 38 is slack when the edge mask 35 is retracted so that the shielding sheet 39 can expand and contract as the edge mask 35 moves forward and backward. The shielding sheet 33 electrically blocks the opposing electrodes 5 at the back of the edge mask 35.

Next, the operation of the electroplating equipment configured as described above will be explained.

Plating solution is supplied to the plating chamber 18 from the static pressure pad 11 and the plating solution auxiliary supply nozzle 23 . The liquid shut-off device 9 is installed so that the plating liquid E does not fill up to the upper end of the plating chamber 18.
Adjust the amount of plating solution flowing out. Since the plating solution E is ejected upward from the horizontal slit 13 above the static pressure pad 11, the flow velocity of the plating solution E above the static pressure pad 11 downward is suppressed.

The plating solution E spouted from the static pressure pad 11
1, static pressure is generated on both sides of the strip S. Therefore, the warpage of the strip S is corrected by this static pressure. Further, the strip S is held by static pressure near the static pressure pad 11, and vibration of the strip S is prevented.

When performing single-sided plating, the electrode 5 facing the surface to be plated
Voltage is applied only to The position of the edge mask 35 is adjusted by the drive rod 37 so as to cover both ends of the strip S. Since both ends are covered by the edge mask 35, the side end facing the zero potential electrode 5 is Not enough current flows for the plating to form. Therefore, the edge mask 35 does not cause the metal to penetrate into this part.
The shielding width of the side end portions varies depending on the current density, distance between electrodes, and other plating conditions, but is approximately 10 to 100 mm.

Further, the shielding sheet 33 electrically isolates the positive potential electrode 5 and the zero potential electrode 5 at the back of the edge mask 35 . Therefore, no unnecessary current flows between both electrodes 5.

Four vertical slots 15 and 18 of the static pressure pad 11 are provided at intervals in the strip width direction. Therefore, even if the edge mask 35 enters inside and blocks the outer vertical slit 1B when the width of the strip S is narrow, the inner vertical slit 15 alone performs sufficient functions of supplying the plating solution and generating static pressure.

Here, a specific example of electroplating using the above equipment will be explained.

Electrolytic conditions Zn5Oa 7H20 concentration in plating solution: 250 g
/fL Plating solution temperature = 60℃ Plating solution pH: 1.5 Free H in the plating solution? SO4 concentration: 21g/cm Distance between anode and cathode 29 layers Capacity Static pressure pad: 2m3. / layer in one side auxiliary header:
0.5■31■in Unilateral static pressure (static pressure pad area)
2425 tag H20 edge mask: Steel strip side edge shielding width 5 layers (a) Double-sided plated copper strip dimensions: Thickness 0.8 fat layer x width 1500 layers l Target plating amount 20 g/m2 (a) on both sides ) Single side plated copper strip dimensions: thickness 0.75 rats x width 1500 a
m Target amount of plating coating 2 Surfaces 20g1■2 Back side Og/1m2 According to this invention, as is clear from the table above, the variation in the amount of plating is less than 5z, and the penetration of plating to the edge of the non-plated surface is Does not occur.

Also, no vibration of the strip occurred during the plating process.

The present invention is not limited to the above-mentioned embodiment. For example, the plating solution tank 1 may be filled with the plating solution until it reaches the upper end of the electrode 5. In this case, the plating solution auxiliary supply header 22 and the nozzle 23 are unnecessary. be. Furthermore, five or more vertical slits 15,1llt may be provided in the static pressure pad 11.

(Effects of the Invention) As described above, according to the present invention, warping of the strip is corrected and vibration is prevented. Therefore, uniform plating can be obtained. Furthermore, the distance between the electrode and the strip can be reduced. Conventionally, this distance was limited to 200 layers, but
According to this invention, it can be reduced to 5 cm. As a result, the voltage between the electrodes can be reduced, and the power is reduced by about 1/2.
savings can be achieved. Furthermore, since the capacity of the plating chamber is reduced, the amount of plating solution supplied can be reduced, and the capacity of the circulation pump can also be reduced to about 1/4. Furthermore, the entire equipment becomes smaller.

Furthermore, since the strip does not vibrate even when passed at high speed, plating efficiency can be increased.

Furthermore, in the case of single-sided plating, the plating does not wrap around to the side edges of the non-plated surface.

A high-quality single-sided plating is obtained in which the non-plated side is not plated at all.

[Brief explanation of drawings]

FIG. 1 shows an example of the present invention, and is a longitudinal sectional view of a vertical electroplating equipment, and FIG. 2 is a side view of the main parts of the equipment.
and FIG. 3 is a sectional view taken along the line ■-■ in FIG. 2. 1... Plating solution tank, 5... Electrode, 11... Static pressure pad, 12... Plating solution spout, 1st... Plating chamber, 20... Ladder to plating solution supply, 22 ... Plating solution auxiliary supply head, 23... Nozzle, 2B... Plating solution circulation pump, '31.32... Conductor roll, 35... Edge mask, 37... Drive rod, 38... ...shielding sheet, S... strip, E
...Plating solution.

Claims (1)

[Claims] A plating solution tank, a set of plate electrodes arranged in the plating solution tank so that the plate surfaces face each other vertically to form a plating chamber, a conductor roll arranged above and below the electrodes, and a plating solution. In the equipment, a pair of opposing static pressure pads each having a plating solution jet opening opening toward the metal strip surface are provided at approximately the center position in the vertical direction of the electrode, and the static pressure pad is 1. An electroplating equipment, characterized in that a plating solution supply device is connected thereto, and an electrically insulating edge mask that covers the side edges of the metal strip between the electrodes is provided so as to be movable in and out in the width direction of the metal strip.