JPS61190095A - Electroplating installation - Google Patents

Abstract

PURPOSE:To inject a plating liquid from upper nozzles and static pressure pads and to plate a steel strip without oscillating the strip by providing the static pressure pads in the intermediate part of the anodes on both sides of the steel strip traveling in a vertical direction and connecting a plating liquid supply device to the nozzles provided in the upper part of a plating chamber and the static pressure pads. CONSTITUTION:The steel strip S is run vertically by conductor rolls 31, 32 in a plating cell 1. The strip S passes between a pair of the rectangular plate-shaped anodes 5 consisting of upper electrodes 6 and lower electrodes 7. the static pressure pads 11 are provided on both side at the intermediate of the upper and lower anodes 6 and 7 and the plating liquid is ejected from ejection ports 12 facing upward and horizontal direction. The steel strip is plated while the camber and oscillation thereof are prevented by the static pressure generated during the ejection. The plating liquid is also supplied from auxiliary supply headers 22 in the upper part of the plating chamber 18. The plating liquid is cyclically supplied by supplying the plating liquid E in the bottom of the plating cell 1 to the headers 20 of the pads 11 and the headers 22 by a pump 26. The spacing between the steel strip and the anodes is thus decreased and the plating with the smaller electric power is made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electroplating 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. A conductor roll is placed in each. A plating solution is supplied between the electrodes. ? ! Plating is performed while passing a strip (cando) guided by an interelectrode conductor roll. A plating solution supply device supplies plating solution between the electrodes.

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 electrodes, the spacing between the electrodes must be increased. 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.

(Means for Solving the Problems) The electroplating equipment of the present invention includes a plating solution tank, a pair of opposing plate electrodes arranged in the plating solution tank so that the plate surfaces are vertical, and It consists of conductor rolls placed above and below, respectively, and a plating solution supply device. The pair of opposing electrodes forms 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 jet opening that opens toward the strip surface. The plating solution supply device is connected to the static pressure pad.

(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, warping of the strip 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.

(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 includes a plating solution tank l, a set of rectangular plate electrodes 5, a 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
and four vertical pickpockets spaced horizontally7) 15.
It consists of 18. Further, as shown in FIG. 1, the upper horizontal slit 13 opens upward, and the lower horizontal slit 14 opens horizontally. The inclination angle α of the upper horizontal slit 13 with respect to the horizontal plane is 0 to
It is 45 degrees. Note that a plating solution supply header 20 is connected to the static pressure pad 11.

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

Directly above the electrode 5, a pair of plating solution auxiliary feeders 22 are arranged. 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 9 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 to adjust the amount of plating solution E flowing out from the plating chamber 18, and the plating solution is supplied to the plating solution supply header 20 and the plating solution auxiliary supply header 22, respectively. Circulation pump 2
Plating solution E is supplied by B.

Conductor rolls 31, 32 are arranged above and below the electrodes 5, respectively. Conductor roll 31
32 guides the strip S so as to keep a constant distance between it and the electrode 5.

Strip S in contact with conductor roll 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.

There is a rubber shielding sheet 3 on the back of the edge mask 35.
One end of the shielding sheet 39 is fixed, and the other end of the shielding sheet 39 is fixed to the inner surface of the side wall 3 of the plating solution tank 1.The edge mask 35 is moved backward so that the shielding sheet 39 can expand and contract according to the advance and retreat of the edge mask 35. When the shielding sheet 39 is in use, the shielding sheet 39 is slack.

The shielding sheet 38 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.

The plating chamber 18 is mainly equipped with a static pressure pad! ! The plating solution is supplied from the auxiliary plating solution supply nozzle 23, and the insufficient amount is supplied from the plating solution auxiliary supply nozzle 23. The outflow amount of the plating solution is adjusted by the liquid shutoff device 9 so that the plating solution E fills the plating chamber 18 up to the upper end. 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 is the static pressure pad L.
A static pressure is created on both sides of the strip S near l. 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 driving rod 37 so as to cover both ends of the strip S. Since both ends are covered by the knee mask 35, the side end facing the electrode 5 at zero potential is does not carry enough current to form a plating, so
Edgemask 3 does not cause plating to penetrate into this area.
The shielding width of the side end portion by No. 5 varies depending on the current density, distance between electrodes, and other plating conditions, but is about 1θ to 100a++s.

Further, the shielding sheet 39 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 slits 1516 of the static pressure pad 11 are provided at intervals in the strip width direction. therefore,
Even if the edge mask 35 comes inside and blocks the outside vertical slit 16 when the width of the strip S is narrow,
The inner vertical slit 15 alone is sufficient to supply the plating solution and generate static pressure.

FIG. 4 shows the static pressure par 2 of the equipment for plating the strip twice: when the strip is lowered and when it is raised. This equipment is equipped with two electrodes 41, 42 and static pressure pads 44, 47 in one plating solution tank l.

The first static pressure pad 44 is the same as in the previous embodiment.

The second static pressure pad 47 has an inclination angle β of the upper horizontal slit 4 and an inclination angle α of the horizontal slit 45 of the first static pressure pad 44.
The structure is exactly the same as that of the first static pressure pad 44 except that it is smaller. The lower horizontal slits 48, 49 are both open in the horizontal direction.

The angle of inclination β of the second static pressure pad is suitably between -35 and ÷45 degrees.

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

Electrolytic conditions Zn5Oa 7H20 concentration in plating solution: 250 g
/l Plating solution temperature: 60℃ Plating solution pH: 1.5 Free H2SO4 concentration in plating solution: 21g/Anode-cathode distance JIIi: 9H1m Liquid volume Static pressure pad: 2 layers 3/layer in One side auxiliary header:
0.5 m3/win One side static pressure (static pressure pad area): 425 mm) 120 edge mask: steel strip side edge shielding width 5 +u+ (a) Double-sided plated copper strip dimensions: thickness 0.8 +uiX width 1500 am Target plating amount: 20 g/m2Ca on both sides Single side plated copper strip dimensions: Thickness 0.75 rgrm x width 1500 a
m Target plating adhesion amount 2 surfaces 20 g/a2 back Og/r
a2 As is clear from the above table, according to the present invention, the variation in the amount of plating is 5z or less. 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 vertical slits 15 and 18 are
The above may be provided, and the plating liquid auxiliary supply header 22
Alternatively, the edge mask 35 may be omitted.

(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 strut can be reduced. Conventionally, this distance was limited to 20 mm, but according to the present invention, it can be shortened to 51aI. As a result, the voltage between the electrodes can be lowered, and the power consumption can be reduced to about 1/2. Also, since the capacity of the plating chamber is smaller, the amount of plating solution supplied can be reduced.

@The ring pump can be reduced to about 1/4 the capacity. Furthermore, the entire equipment becomes smaller.

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

[Brief explanation of the drawing]

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.
FIG. 3 is a sectional view taken along the line ■--■ in FIG. 2, and FIG. 4 is a sectional view showing an example in which two sets of static pressure pads are provided. DESCRIPTION OF SYMBOLS 1... Plating solution tank, 5... Electrode, ll... Static pressure pad, 12... Plating solution spout, 18... Plating chamber, 20... Plating solution supply header, 22... - Ladder to plating solution auxiliary supply, 23... Nozzle, 26... Plating solution circulation pump, 31. 32... Conductor roll, 35... Edge mask, 37... Drive rod, 39
...shielding sheet, S... strip, E... plating solution.

Claims (1)

[Claims] A plating solution tank, a set of plate-shaped 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 plating. In the equipment, a pair of opposing static pressure pads each having a plating solution outlet 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 Electroplating equipment, characterized in that the plating solution supply device is connected thereto.