JP3264479B2 - Method for controlling bath rate of plating solution in continuous electroplating equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plating solution bath control method in a continuous electroplating facility, which is suitable for controlling the total bath volume of a plating solution in a continuous electroplating facility.

[0002]

2. Description of the Related Art Conventionally, when plating a strip such as a steel strip, a plurality of plating cells for continuously performing electroplating while sequentially passing a conveyed strip, and a plating solution is circulated and supplied to each plating cell. Cleaning equipment that cleans the strip after plating on the outlet side of the final plating cell and flows the cleaning water into the circulation equipment in order to restore the plating solution components that have been washed away. A continuous electroplating facility including an evaporator for evaporating inflow water such as washing water flowing into the plating facility is used.

[0003] In such plating equipment, since the strip before plating is washed on the entrance side of the plating equipment, water attached to the strip flows into the plating equipment. or,
Since the strip after plating is washed on the outlet side of the final plating cell as described above, in order to recover the plating solution components contained in the washing water used for the washing, the washing water is used for plating equipment. So that it flows into

Therefore, when water flows from outside the plating equipment (circulation system) as washing water into the plating equipment (circulation system), the plating solution is diluted with the inflow of water, so that water evaporation for removing excess water is performed. The operation is performed by the evaporator device, and a balance is made between the amount of water flowing into the system and the amount of water evaporated outside the system.

[0005] In order to perform high-precision plating with the plating equipment as described above, it is important to control the concentration of the plating solution to a target value. Conventionally, water evaporation by the evaporator device has been left to the operator's operation.

[0006]

However, in the bath volume control by the operator for the evaporator apparatus, the operator measures the level measurement value of the circulation tank for circulating the plating solution as a representative value of the total bath volume. In some cases, the following erroneous operation is performed.

(1) When the circulating flow rate to the plating cell is changed, the amount of bath in the return pipe from the cell changes, so that the level measurement value of the circulating tank fluctuates.

(2) Ancillary equipment (evaporator device, filter device for removing impurities, mixing device for supplying pure water, etc.) has a problem that the bath volume changes in a certain process, so Give fluctuation. For example, in the filter device, the inside of the main filter is temporarily emptied by backwashing.

[0009] If the fluctuation of the level meter measurement value due to the above (1) or (2) is mistaken for an increase in the inflow of water from outside the system and the water is excessively evaporated by the evaporator device, the plating solution is concentrated. As a result, the plating solution concentration increases. Conversely, if the amount of water evaporation from the evaporator device is insufficient while the amount of water flowing from outside the system is actually increasing, the plating solution is diluted and the concentration is reduced.

In general, in electroplating using an insoluble anode, the concentration of a plating solution component of free ions such as metal ions and sulfuric acid dissolved in the plating solution is controlled. Predicted metal consumption, which is predicted to be consumed in plating from the plating conditions (feed forward: FF) to maintain the metal ion concentration at the target value,
In addition, the sum of the metal deviation amount obtained from the deviation between the actual concentration value and the predetermined concentration target value is set as the metal input amount during the metal ion concentration feedback (FB) control.

As described above, in the feedback (FB) control of the metal ion concentration in the conventional concentration control, the feedback is performed based on the deviation between the predetermined target value of the metal ion concentration and the measured value of the metal ion concentration. Metal ions are supplied to the plating solution.

By the way, when the plating solution is diluted due to an increase in the total bath volume due to the inflow of water from outside the system, as described above, the measured metal ion concentration ([g / l] or [mo
l / l]) as a result. At this time, if the metal ions are supplied in order to keep the metal ion concentration constant, in the case of a sulfuric acid (H2 SO4) acidic Zn-Ni alloy plating solution, the dissolution reaction of (A) and (B) is performed. H
2 SO4 decreases (or pH increases). As a result, H
In order to keep the 2 SO4 concentration (or pH) constant, sulfuric acid is added.

Zn + H 2 SO 4 → ZnSO 4 + H 2… (A) Ni + H 2 SO 4 → NiSO 4 + H 2 ↑ (B)

Normally, in Zn-Ni alloy electroplating, the metal (Z) is formed by the following plating reactions (C), (D) and (E) on the cathode (steel plate) surface and the anode (insoluble electrode) surface.
n, Ni) ions are consumed and H2 SO4 is increased. Therefore, in the electroplating, the metal ions consumed by the plating of (C) and (D) are supplied by the reactions of (A) and (B), whereby the amount of metal ions in the plating solution and the H2 of (E) are increased. H2SO4 due to the increased reaction of SO4
The amount is also balanced.

Zn ²⁺ + e ⁻ → Zn ↓... (C) Ni ²⁺ + e ⁻ → Ni ↓... (D) H 2 O + SO 4 ^2- → H 2 SO 4 + 1 / 2O 2 ↑ (E)

Therefore, when sulfuric acid is introduced when the total bath volume of the plating solution increases due to the inflow of water into the system, the total bath volume of the plating solution returns to the target value due to the subsequent evaporation of water by the evaporator device. At times, the amounts of metal ions and H2 SO4 in the plating solution both become excessive. Thereafter, the metal ions are reduced by the plating reactions of (C) and (D) by stopping the supply of the metal agent and stopping the dissolution reactions of (A) and (B), but H2 SO4 is reduced by (A ), There is no decrease due to the dissolution reaction of (B), only the increase due to the plating reaction of (E), the H2SO4 amount further increases, and the H2SO4 concentration is balanced at a high (or low pH).

To reduce the unit cost of electroplating, reducing the plating current has a great effect. To reduce the plating current is to improve the electrodeposition efficiency.
It is an effective means to aim at lower (higher) SO4 concentration (or pH) within the control range. Therefore, H
2 SO4 concentration should never be balanced at high (or low pH) values.

The present invention has been made to solve the above-mentioned conventional problems, and it is possible to control the total bath volume of the plating solution with high precision with a minimum loss of the plating solution. An object of the present invention is to provide a plating solution bath amount control method in a continuous electroplating facility that can control the component concentration with high accuracy.

[0019]

SUMMARY OF THE INVENTION The present invention provides a plurality of plating cells for continuously performing electroplating while sequentially passing a conveyed strip, a circulating facility for circulating and supplying a plating solution to each plating cell, On the outlet side of the plating cell, the strip after plating is washed, and the washing water flows into the circulation facility in order to return the washed-out plating solution components to the original state. In the plating solution bath amount control method in a continuous electroplating facility having an evaporator for evaporating inflow water such as washing water, the continuous electroplating facility has an insufficient evaporator water evaporating capacity and an excessive plating solution. Installed a drainage facility to be used when the plating solution drops, and a pure water supply facility to supply water when the plating solution is low, and measure the amount of water flowing into the plating facility from outside the system Is the sum of the water inflow speed obtained Te predicted controlled variables Z _FF, the deviation ΔV between the bath amount target value set in advance and the total bath amount measurement value of the entire plating equipment, and feedback is determined based on the deviation ΔV From the control amount Z _FB , using the at least one element of Z _FF , Z _FB and ΔV, the evaporator is used such that the total bath amount of the plating solution is maintained at the target value of the bath amount with minimum loss of the plating solution. At least one of the three operating terminals consisting of a device, drainage equipment and pure water supply equipment
The above problem has been solved by deciding one of the two and operating it to control the total bath amount.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION
Plating cells, continuously determine the total bath volume of plating solution from changes in the plating process signal input from a level meter attached to a circulation tank or a flow meter attached to piping, etc., and
A deviation ΔV from the target value of the total bath amount, a feedback control amount Z _FB of the bath amount based on the deviation ΔV are obtained, and a measurement of an amount of water flowing per unit time as washing water or the like into the plating equipment (circulation system). By calculating the predicted control amount Z _FF of the bath amount from the value, the bath amount control amount Z is obtained from the sum of Z _FF and Z _FB, and when controlling the control amount Z, the deviation ΔV is also taken into consideration. In order to select the most suitable operation end, the total bath volume of the plating solution is controlled with high precision by automatically controlling the water evaporation amount of the evaporator device.

However, even when the control according to the present invention as described above is carried out, a bath amount fluctuation of about 5% with respect to the bath amount target value may occur. Therefore, the invention of claim 4 is applied to such unavoidable fluctuations in the amount of bath. In this case, the measured value of the bath amount target value Vsp and the plating solution total bath amount Vall is used to correct the metal ion concentration target value CTMsp set at the time of concentration control, so that water inflow from outside the system is corrected. When the plating solution is diluted (total bath volume is increased) by metal ion feedback (F
B) Excessive supply of metal ions by control can be prevented, and by suppressing the addition of sulfuric acid due to excessive supply of metal ions, a stable H2SO4 concentration (or pH) can be obtained.
Can be maintained.

The present invention will be described in further detail. Since the definition of the metal ion concentration ([g / l] or [mol / l]) is the amount of metal ions per unit bath amount of the plating solution, the metal ion concentration is constant. If the total bath volume of the plating solution fluctuates below, the metal ion concentration naturally fluctuates. The value CTC after the fluctuation of the metal ion concentration with respect to the fluctuation of the total bath amount of the plating solution.
M is given by equation (1).

CTCM = (CTMsp + CAsp / Ma) × Vsp / Vall−CAsp / Ma [mol / l] (1) where CTMsp: target value of metal ion concentration [mol / l] Vsp: target value of plating solution total bath amount [M ³ ] CAsp: Target value of H2 SO4 concentration [g / l] Vall: Measured value of total bath volume of plating solution [m ³ ] Ma: H2 SO4 molecular weight = 98

The following equation (2) is the original form of the above (1), and expresses that the sulfuric acid concentration is maintained at the target value even when the total bath amount Vall fluctuates.

CTMsp × Vsp + (CAsp / Ma) × Vsp = CTCM × Vall + (CAsp / Ma) × Vall (2)

Therefore, by rearranging the equation (2), the metal ion concentration due to the change in the bath volume: CTCM [mol / l
] Is obtained by the above equation (1).

More detailed description will be given by giving specific numerical examples.
Bath amount target value Vsp = 430 m ³ , metal ion concentration target value C
TMsp = 2.0 mol / l, H2 SO4 concentration target value CAsp =
When the plating solution is diluted with water and becomes Vall = 480 m ³ (conventionally, a variation of deviation ΔV = 50 m ³ was unavoidable in the case of 13 g / l), the metal was obtained from the above formula (1). The ion concentration decreases to CTCM = 1.78 mol / l.

In some cases, the control range of the metal ion concentration in terms of quality is defined as ± 0.2 mol / l in the alloy plating solution. In this case, the metal ion concentration falls outside the control range.

[0029] In the present invention, as described above, together with obtaining the continuous plating solution total bath volume from a signal change in the plating process, by the automatically controlled water evaporation amount of the evaporator unit, the above examples of Vsp = 430m ³ In the case of, the variation ΔV of the plating solution total bath volume is suppressed to ± 20 m ³ or less,
The metal ion concentration can be suppressed to within ± 0.1 mol / l from the above equation (1).

In controlling the concentration of the plating solution component when the total bath volume Vall fluctuates, the target value of the metal ion concentration CTMsp
Instead of [mol / l], the CTCM obtained by equation (1) is set as a corrected metal ion concentration target value CTCMsp [mol / l], and in order to eliminate the concentration deviation from the corrected target value,
By performing the metal ion feedback (FB) control, when ΔV = ± 20 m ³ , that is, the total bath target value Vsp =
430 m ³ , metal ion concentration target value CTMsp = 2.0mo
l / l and the target value of H2 SO4 concentration CAsp = 13 g / l, the plating solution was diluted with water and Vall = 450 m
^{When the value is 3} , the metal ion concentration is C from the equation (1).
TCM = 1.91 mol / l. Therefore, even when the bath volume fluctuates, an excessive supply of metal is prevented, and as a result, excessive sulfuric acid input is suppressed.
The concentration (pH) can be maintained.

Hereinafter, a more specific embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing a schematic configuration of a continuous electroplating facility applied to a plating solution bath amount control method according to one embodiment of the present invention.

The continuous electroplating equipment is provided with a plurality (for example, about 20 units) (not shown) for continuously performing electroplating while sequentially passing steel strips (strips) S continuously conveyed in the direction of the arrow. A) a plating cell 10 using an insoluble anode, circulating equipment including a circulating tank 12 and piping for supplying a plating solution to each plating cell 10 while circulating the plating liquid, and various auxiliary equipment described below. And constitutes a plating solution circulation system as a whole.

As the additional equipment, a cleaning equipment 14 for cleaning the plated steel strip S is provided on the exit side of the last plating cell 10A located at the end of the plating cell 10. In the cleaning equipment 14, pure water is introduced by opening and closing the valve 14A, and when the steel strip S is cleaned, the cleaning water flows into the circulation equipment via the pan 14B so that the plating solution component is recovered. It has become.

An evaporator for evaporating and removing water flowing into the plating equipment, such as cleaning water flowing from the cleaning equipment 14 and water adhering to the steel strip S from the entrance side of the plating cell 10. An apparatus 16 is provided.

Further, as ancillary equipment, there is provided a drainage equipment 18 for discharging the plating solution from the system when the evaporator 16 cannot completely evaporate and the plating solution becomes excessive. The drainage facility 18 includes a flow meter 18A and a valve 18B, and is disposed in the cleaning facility 14 at a position where the mixing of plating solution components is minimized.

On the other hand, the continuous electroplating equipment is provided with a mixing device (pure water supply equipment) 20 for replenishing water when the plating solution decreases.

Further, as other auxiliary equipment, a filter device 22, a metal dissolving device 24 for dissolving a metal agent (metal itself, oxide thereof, etc.) for supplying metal ions such as Zn ions and Ni ions, etc. are provided. Has been established.

Accordingly, in the present embodiment, the plating solution circulation system is constituted by the plating cell 10, the circulation tank 12, each of the auxiliary facilities 16 to 24, and the piping connecting these.

In this embodiment, in response to excessive inflow of water from outside the system into the plating solution circulation system, the metal in the plating solution is not discharged out of the system and the plating solution existing in the circulation system is discharged. In order to keep the total bath amount, which is the total amount, constant, the bath amount control includes bath amount FF control for evaporating water flowing into the circulation system and bath amount FB control based on the total bath amount result. I do.

Here, the total bath amount Vall is the total amount of the plating solution contained in the plating cell, the circulation tank, the auxiliary equipment, and the like, and is the total amount of the plating solution used in a normal operation.
This is because the entire equipment is divided into a plurality of blocks, and a process computer (not shown) calculates each control cycle based on a process signal input from a level meter or the like attached to each block. It is determined by the formula.

Vall = ΣVsi [m ³ ] (3) where Vsi is the actual bath amount of the i-th block.

Here, the actual value of the circulating bath amount Vrot used for the feedback control of the plating solution component concentration is calculated by the following equation (4). This is the amount of plating solution that is actually circulating in the circulating system at each time in the total bath volume, and is the plating solution contained in blocks such as equipment that are not in use by bypassing the flow of the solution. Is excluded from the total bath volume.

Vrot = Vall−ΣVsj [m ³ ] (4) where Vsj is the actual bath capacity of the j-th block being bypassed.

The circulating bath volume Vrot is determined by the amount of metal ions or H2
This is used for feedback (FB) control of SO4 concentration in order to prevent excessive injection of chemicals.

In the present embodiment, the water flowing into the plating facility from outside the system is measured by flow rate calculation, and the predicted control amount Z _FF [m ³ / h] is obtained as the sum of the water inflow speeds.

At the same time, a deviation ΔV between the actual value of the total bath amount Vall and a predetermined bath amount target value Vsp is calculated, and feedback control of the bath amount determined based on the ΔV is performed. _{Determine the} quantity _ZFB .

[0048] The Z _FF, in addition to the washing water taken from the washer equipment 14 located side out plating cell described above, all such as those water used in cell entry side is brought to adhere to the steel strip Calculated as the sum of inflow water.

The Z _FB is obtained by the following equation (5). Note that k _ZFB is a feedback coefficient.

Z _FB = k _ZFB × ΔV (5)

In this embodiment, as described above, each control cycle
Three elements Z obtained for each (calculation time) _FF, Z_FBAnd ΔV
The evaporator device 1 using at least one of
6. Drainage equipment 18 on the cell outlet side and mixing device 20
Determine at least one of the three operating terminals and select it
Therefore, at least three operations consisting of the following (1) to (3)
By doing one, with minimal loss of plating solution,
Control is performed to maintain Vall at the target value Vsp.

(1) Only water in the plating solution is removed by evaporation using an evaporator.

(2) Although the plating solution is slightly mixed in by the drainage device 18, the cleaning water is discharged to reduce Vall.

(3) Pure water is supplied to the plating solution by the mixing device 20.

More specifically, as shown in Table 1 below, the condition of the time is met by dividing the bath amount control amount Z obtained by the following equation (6) and the bath amount deviation ΔV into consideration. Determined control operation and execute it. The above processing flow is summarized in FIG.

Z = Z _FF + Z _FB [m ³ / h] (6)

That is, the bath amount control amount Z is determined by the above equation (6), and the upper and lower reference values for determining the bath amount deviation are set within an allowable control target range. here,
The control target range is ± 20 m ³ around the bath amount target value Vsp, the upper reference value is +10 m ³ , and the lower reference value is −10 m ³ .

The control of the total bath amount is performed mainly by water evaporation by operating the evaporator device 16.

At this time, when the bath amount control amount Z is within the evaporation capacity of the evaporator, when the deviation ΔV is smaller than the lower reference value, that is, when ΔV <−10 m ³ , the mixing device (pure water supply equipment) Operate 20 to supply pure water. At this time, only flash evaporation is performed in the evaporator device 16.

In the evaporator device 16, in order to improve the evaporation capacity (lower the boiling point), a vacuum is drawn by suction with a vacuum pump, and the evaporation operation is performed under that state. Once the vacuum is broken just because there is no need to evaporate the water, it takes a long time to re-create the vacuum afterwards.

Therefore, in order to minimize water evaporation without destroying the vacuum state when water evaporation is unnecessary, an operation method of stopping the evaporation operation while maintaining the vacuum state is adopted. The flash evaporation is an operation involving the minimum evaporation which is unavoidable in terms of work efficiency, and substantially means the stop of evaporation.

When the bath amount control amount Z exceeds the evaporation capacity of the evaporator device 16, when the deviation ΔV exceeds the same value as the evaporation capacity, the drainage equipment is operated. Drain.

In the present embodiment, the evaporator 16 has two types of evaporative power, 1 ton and 3 ton. Therefore, its capacity (maximum value) is 4 ton of the sum of the two, which corresponds to 4 m ³ .

Therefore, Z> 4 [m ³ / h] and ΔV>
At 4 m ^3, the maximum value of 4 tons (4 m ³ ) per hour was evaporated by the evaporator device,
Drain from 8 is performed.

At this time, in the present embodiment, cases are further divided, and in the drainage equipment 18, when 4 <ΔV ≦ 10m ³ , the excess discharge for discharging the inflow exceeding the evaporation capacity of the evaporator device is performed in an amount of 10m ³ < At ΔV, constant discharge is performed.

Here, the former excessive discharge is a discharge operation only for maintaining the current bath amount, and the discharge amount at that time is obtained by the following equation.

Inflow rate = water evaporation capacity of evaporator device +
Excess emission (amount)

The latter constant discharge is a discharge operation for always lowering the bath amount, and the discharge amount at that time is obtained by the following equation.

Inflow <water evaporation capacity of evaporator device +
Constant emission (amount)

[0070]

[Table 1]

The control operations a, b and c shown in Table 1 and their details are as follows.

A. Pure water input operation by mixing device a-0 operation. No input: Zw [m ³ / h] → Zw = 0 [m
³ / h] a-1 Operation. Pure water input: Zw [m ³ / h] Pure water input by a mixing device → Zw = −k1 × (ΔV + 10) [m ³ / h] where k1: variable constant b. Evaporation operation by evaporator device b-0 operation. Flash evaporation Vacuum evaporation mode (flash) of the evaporator b-1 operation. 1 ton evaporation mode (1 ton booster operation) b-2 operation. 3 ton evaporation mode (3 ton booster operation) b-3 operation. MAX evaporation mode (1ton booster, 3
drive with ton booster) c. Cell discharge liquid discharge control operation c-0 operation. No discharge: Zd [m ³ ] → Zd = 0
[M ³ ] c-1 operation. Excessive discharge: Zd [m ³ ] The inflow exceeding the evaporation capacity of the evaporator device is discharged. c-2 operation. Constant discharge: Zd [m ³ ] → Zd = constant [m
³ ]

According to the bath volume control method of the present embodiment described in detail above, in the above-mentioned plating facility with the bath volume target value Vsp = 430 m ³ , the conventional limit of ΔV = ± 50 m ³ / h is changed to ΔV = ± 20 m ³ / h.

In the present embodiment, the largest flow of water flowing into the plating facility is due to pure water supplied from the cleaning facility 14 on the cell outlet side. Therefore, the bath amount can be easily controlled by fully utilizing the drainage control by the drainage facility 18 and increasing the drainage amount, but since some plating solution components are mixed in the drainage, The basic unit deteriorates. Also, if the evaporator device is provided with an evaporating capacity larger than the amount of water flowing in due to the supply of pure water from the cell outlet side, control can be similarly performed, but the equipment cost of the device increases.

Therefore, in the present embodiment, the system shown in Table 1 above is adopted, and the total bath amount control mainly by water evaporation by the evaporator device 16 is performed. In addition, here, ± 10 m ³ was used as the upper and lower reference values to determine the bath amount deviation. However, when the control target range was ± 20 m ³ , the response of pure water input by the mixing device 20 was as follows. Alternatively, it is determined by the response of the drainage by the drainage facility 18 on the cell exit side. That is, if these responsivenesses are good, the absolute value of the upper and lower reference values can be increased so as to be as close as possible to 20 m ³ , and if it can be increased, water evaporation by the evaporator device 16 within the control target range can be prevented. The main control range can be further expanded.

In the present embodiment, if the bath amount deviation ΔV occurs as a result of the above bath amount control, the concentration control is further performed as follows.

That is, the correction target value CTMCsp of the metal ion concentration set at the time of the concentration control is obtained by the following equation (7) derived in consideration of Vrot in the above equation (1). Then, in the metal ion concentration FB control in the concentration control, this CTMCsp is used instead of CTMsp.

CTMCsp = CTMsp · (Vrot + Vsp−Vall) / Vrot + (CAsp / Ma) · (Vsp−Vall) / Vrot [mol / l] (7) CTMsp: a predetermined metal ion concentration target value [ mol /
l] CTMCsp: Corrected metal ion concentration target value [mol / l] Vsp: Bath amount target value [m ³ ] Vall: Total bath amount [m ³ ] Vrot: Circulating bath amount [m ³ ] CAsp: H2 SO4 concentration target value [G / l] Ma: H2 SO4 molecular weight [g / mol]

This equation (7) can be derived by rearranging the following equation (8). That is, the target total SO4 ^2- root amount is as shown on the left side of the following equation, and the corrected metal ion concentration so as not to affect the metal ion concentration in the incidental equipment separated from the circulating system and the overall H2 SO4 concentration. (CTMC
sp), it looks like the right side.

CTMsp · Vsp + (CAsp / Ma) · Vsp = CTMCsp · Vrot + CTMsp · (Vall−Vrot) + (CAsp / Ma) · Vall [kmol] (8)

According to the present embodiment, when the bath amount target value Vsp of the plating solution is 430 m ³ , the total bath amount fluctuation can be controlled within ± 20 m ³ , and as a result, the metal ion concentration can be controlled by ± 1 mol. / l or less.
The 2 SO4 concentration can be stabilized at the target value.

As a result, the effects of stabilizing the quality of the electroplated product (the adhesion amount of the plating metal and the alloy ratio), improving the electrodeposition efficiency, and reducing the plating current were obtained.

[0083]

As described above, according to the present invention,
The total bath volume of the plating solution can be controlled with high precision with a minimum loss of the plating solution.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of a plating facility applied to one embodiment according to the present invention.

FIG. 2 is a flowchart showing a processing procedure in the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Plating cell 12 ... Circulation tank 14 ... Cleaning equipment 16 ... Evaporator equipment 18 ... Drainage equipment 20 ... Mixing equipment 22 ... Filter equipment 24 ... Metal melting equipment

Claims (4)

(57) [Claims] 1. A plurality of plating cells for performing electroplating continuously while sequentially passing a conveyed strip, a circulating facility for circulating a plating solution to each plating cell, and plating on the outlet side of the final plating cell. In addition to cleaning the subsequent strip, cleaning equipment is designed to allow cleaning water to flow into the circulation equipment in order to restore the plating solution components that have been washed away, and evaporating water that flows into the plating equipment, such as cleaning water. A plating solution bath control method in a continuous electroplating facility comprising an evaporator and a drainage facility used when the plating solution becomes excessive due to insufficient water evaporation capacity of the evaporator apparatus. In addition to installing a pure water supply facility to supply pure water when the plating solution decreases, the water inflow rate obtained by measuring the amount of water flowing into the plating facility from outside the system Sum is a predicted controlled variable Z _FF of, from the feedback control amount Z _FB determined based on the deviation [Delta] V, and the deviation [Delta] V between the bath amount target value set in advance and the total bath amount measurement value of the entire plating equipment, The evaporator device, the drainage device, and the like are used by using at least one element of Z _FF , Z _FB and ΔV so that the total bath amount of the plating solution is maintained at the target value of the bath amount with minimum loss of the plating solution. 3 consisting of pure water supply equipment
A method for controlling a bath amount of a plating solution in a continuous electroplating facility, wherein at least one of the operation terminals is determined and operated to control a total bath amount. 2. The method according to claim 1, wherein the bath control amount Z is obtained as a sum of the predicted control amount Z _FF and the feedback control amount Z _FB , and an upper and lower reference value for determining a bath amount deviation is allowed. The control is performed within the control target range, and the control of the total bath amount is mainly performed by water evaporation by the operation of the evaporator device. When the bath amount control amount Z is within the evaporation capacity of the evaporator device, the deviation ΔV decreases. When the value is smaller than the reference value, the pure water supply equipment is operated to supply pure water. When the bath amount control amount Z exceeds the evaporation capacity of the evaporator device, the deviation ΔV is equal to the evaporation capacity. A method for controlling a plating solution bath amount in a continuous electroplating facility, wherein the drainage facility is operated to drain the liquid when the value exceeds the value. 3. A plating solution bath control method in a continuous electroplating facility according to claim 1, wherein said drainage facility is installed at a position where mixing of a plating solution component is minimized. 4. The method according to claim 1, wherein when a deviation occurs between the measured total bath amount Vall of the entire plating facility and a predetermined bath amount target value Vsp, the feedback control of the metal ion concentration is performed in advance. A continuous electroplating facility characterized in that a set metal ion concentration target value CTMsp and a corrected metal ion concentration target value CTMCsp obtained based on the total bath amount measurement value Vall and the bath amount target value Vsp are set and performed. Method for controlling the bath volume of plating solution.