Alkaline nickel preplating solution maintenance system and method

Abstract

The invention relates to the technical field of surface engineering, and particularly discloses an alkaline nickel preplating solution maintenance system and method. Comprising a sampling unit for sampling a solution in a pre-plating tank, an analysis unit for analyzing the solution taken by the sampling unit, a control unit connected with the analysis unit and the sampling unit, and a liquid adding unit connected with the control unit and used for adding liquid into the pre-plating tank, and the control unit controls the liquid adding unit to add liquid into the pre-plating tank according to the analysis data provided by the analysis unit, so that the plating liquid in the pre-plating tank is in a process requirement range. According to the method, the alkaline pre-nickel-plating main salt component in the alkaline pre-nickel-plating solution can be in a process requirement range for a long time, and the state of the plating solution is effectively monitored, so that the binding force of a chemical nickel-plating layer is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of surface engineering, and more particularly to an alkaline pre-nickel plating solution maintenance system and method. Background Art

[0002] The chemical nickel plating process is widely used in the aerospace industry, military industry, automobile industry, electronics and computer industry to modify the surface of metals, composite materials and non-metallic materials to improve their corrosion resistance, wear resistance, weldability, conductivity, heat resistance and other properties. Pre-nickel plating is a pretreatment process for chemical nickel plating. It protects the chemical nickel plating solution from impurities and increases the bonding strength of the nickel plating layer. Therefore, it is very important to maintain the main salt composition of the pre-nickel plating solution within the process requirements.

[0003] However, according to actual production, the composition of alkaline pre-nickel plating changes rapidly with use and is easily out of adjustment and scrapped. Especially in automated mass production, timely adjustments are required to ensure that its main salt composition is within the process requirements.

[0004] The traditional chemical titration analysis and manual addition of main salt are too slow and difficult to adapt to the automated batch production mode. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide an alkaline pre-nickel plating solution maintenance system and method. The present invention can keep the main salt components of the alkaline pre-nickel plating solution within the process requirement range for a long time and effectively monitor the state of the plating solution, thereby ensuring the bonding strength of the chemical nickel plating layer; the main components of the alkaline pre-nickel plating process are: nickel sulfate 10-40g / L, ammonium chloride 10-30g / L, sodium citrate 20-60g / L, sodium hypophosphite 10-40g / L, pH 8.5-9; the process conditions are: temperature 30-60°C.

[0006] The solution adopted by the present invention to solve the technical problem is:

[0007] on the one hand:

[0008] A maintenance system for alkaline nickel pre-plating solution is used in conjunction with a pre-plating tank, comprising a sampling unit for sampling a solution in the pre-plating tank, an analysis unit for analyzing the solution taken by the sampling unit, a control unit connected to the analysis unit and the sampling unit, and a liquid adding unit connected to the control unit and used for adding liquid to the pre-plating tank; the control unit controls the liquid adding unit to add liquid to the pre-plating tank according to analysis data provided by the analysis unit, so that the plating solution in the pre-plating tank is within the process requirement range.

[0009] In some possible implementations, in order to effectively implement solution sampling in the pre-plating tank and implement filtering and defoaming treatment of the corresponding solution;

[0010] The sampling unit comprises a sampling tube connected to the pre-plating tank, a filter, a sampling pump and a defoamer sequentially installed on the sampling tube, and the defoamer is arranged at one end of the sampling tube close to the analysis unit.

[0011] In some possible implementations, in order to effectively cool the taken solution;

[0012] The sampling unit also includes a radiator which is arranged on the sampling tube and located between the filter and the pre-plating tank.

[0013] In some possible implementations, in order to effectively analyze and detect the pH value and nickel content of the solution taken by the analysis unit;

[0014] The analysis unit includes a pH probe and a nickel probe for extracting the solution taken by the sampling unit, and an analysis module connected to the pH probe and the detection probe and used for analyzing and detecting the pH value and the nickel content; the analysis module is connected to the control unit, and the solution after analysis and detection flows back to the pre-plating tank through the reflux pipe.

[0015] In some possible implementations, in order to effectively add liquid to the pre-plating tank through the liquid adding unit to adjust the pH value and nickel content of the solution in real time;

[0016] The liquid adding unit includes a tank A storing liquid A, a tank B storing liquid B, a metering pump A connected to a control unit and used for extracting liquid A and adding it to a pre-plating tank, and a metering pump B connected to the control unit and used for extracting liquid B and adding it to the pre-plating tank; the liquid A is a liquid mainly containing nickel sulfate and sodium hypophosphite; the liquid B is a liquid mainly containing ammonia water.

[0017] In some possible implementations, in order to discharge the volatile gas in slots A and B in a timely manner;

[0018] The slot A and the slot B are respectively provided with exhaust pipes.

[0019] on the other hand:

[0020] A maintenance method for an alkaline pre-nickel plating solution maintenance system according to the above-mentioned method specifically comprises the following steps:

[0021] Step S1: The sampling unit samples the solution from the pre-plating tank and transports it to the analysis unit;

[0022] Step S2: The analysis unit detects the pH value and nickel content of the solution, and transmits the analysis and detection data to the control unit, and the solution after analysis and detection flows back to the pre-plating tank;

[0023] Step S3: The control unit controls the liquid adding unit to add liquid A mainly containing nickel sulfate and sodium hypophosphite and / or liquid B mainly containing ammonia water into the pre-plating tank according to the analysis and detection data, until the nickel content and pH value in the solution reach the set values ​​respectively.

[0024] In some possible implementations, the step S1 specifically refers to: the sampling pump is started, the solution flows from the pre-plating tank into the liquid collection tube, and enters the analysis unit after being cooled, filtered, and defoamed.

[0025] In some possible implementations, step S2 specifically refers to:

[0026] The pH probe extracts the solution, and the analysis module uses potentiometric analysis to analyze the pH value of the test solution and transmits the pH value data to the control system;

[0027] The nickel probe extracts the solution, and the analysis module uses the photoelectric colorimetric principle to analyze the nickel content in the solution and sends the nickel content data to the control system;

[0028] The solution after analysis and detection flows back into the pre-plating tank through the reflux pipe.

[0029] In some possible implementations, step S3 specifically refers to:

[0030] The control system receives and processes the pH value data and the nickel content data, determines whether the nickel content and the pH value in the solution are within the set range, and transmits the analysis results to the display system connected to the control system;

[0031] If the analysis result is lower than the set value, the control system controls the liquid adding unit to add liquid A and / or liquid B into the pre-plating tank to adjust the nickel content and pH value in the solution in real time.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] The present invention can analyze the solution in the pre-plating tank in real time, and display the analysis and detection results in real time, and add liquid to the pre-plating tank through the liquid adding unit, so as to achieve "less addition and more frequent addition", ensure that the nickel content and pH value meet the requirements, improve the consistency of the solution components in the pre-plating tank, and ensure the quality of the chemical nickel plating layer;

[0034] The present invention proposes to reasonably prepare two additive components of liquid A and liquid B and their concentrations according to the production status, and can effectively adjust other components in the pre-nickel plating while supplementing the nickel content and adjusting the pH value, so that the pre-plating solution can remain stable for a long time;

[0035] The present invention processes the sampling solution by arranging a radiator, a filter and a defoamer, so that the nickel metal entering the analysis unit is free of impurities and bubbles, thereby avoiding affecting the accuracy of the analysis result;

[0036] The present invention can effectively discharge the volatile gas in the groove A and the groove B by arranging the exhaust pipe;

[0037] Compared with the prior art using artificial chemical titration analysis and manual addition, the present invention can make the solution composition more stable, can effectively control the alkaline pre-nickel plating main salt composition in the solution to be within the process requirement range for a long time, and meet the needs of automated batch production. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a structural schematic diagram of the present invention. DETAILED DESCRIPTION

[0039] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral body; it can be directly connected, or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. The "first", "second" and similar words mentioned in this application do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, "one" or "one" and other similar words do not indicate a quantity restriction, but indicate the existence of at least one. In the implementation of this application, "and / or" describes the association relationship of the associated objects, indicating that there can be three relationships, for example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In the description of the embodiments of the present application, unless otherwise specified, the meaning of "multiple" refers to two or more. For example, multiple positioning columns refer to two or more positioning columns. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] The present invention is described in detail below.

[0041] Embodiment 1:

[0042] like Figure 1 As shown:

[0043] An alkaline nickel pre-plating solution maintenance system is used in conjunction with a pre-plating tank, wherein the alkaline nickel pre-plating solution is stored in the pre-plating tank;

[0044] The alkaline nickel pre-plating solution maintenance system includes a sampling unit for sampling the solution in the pre-plating tank, an analysis unit for analyzing the solution taken by the sampling unit and obtaining the pH value and the nickel content, a control unit connected to the analysis unit and the sampling unit, and a liquid adding unit connected to the control unit and adding liquid to the pre-plating tank according to the analysis and detection results of the analysis unit; the control unit controls the liquid adding unit to add liquid to the pre-plating tank according to the analysis data provided by the analysis unit, so that the plating solution in the pre-plating tank is within the process requirement range.

[0045] In some possible implementations, in order to effectively implement solution sampling in the pre-plating tank and implement filtering and defoaming treatment of the corresponding solution;

[0046] The sampling unit comprises a sampling tube connected to the pre-plating tank, a filter, a sampling pump and a defoamer sequentially installed on the sampling tube, and the defoamer is arranged at one end of the sampling tube close to the analysis unit.

[0047] Furthermore, a filter is also provided at the connection end between the sampling tube and the analysis unit; the solution is filtered in two stages by two sets of filters to prevent deposited nickel and other impurities from entering the analysis unit and affecting the analysis results;

[0048] The defoamer processes the bubbles in the taken solution so that there are no bubbles in the solution entering the analysis unit;

[0049] Furthermore, in order to speed up the cooling of the chemical solution in the plating solution, the sampling tube adopts Teflon tube and U-shaped titanium tube, which cooperates with the heat dissipation device to assist heat dissipation and reduce the deposition of nickel in the pipeline.

[0050] In some possible implementations, in order to effectively cool the taken solution;

[0051] The sampling unit also includes a radiator which is arranged on the sampling tube and located between the filter and the pre-plating tank.

[0052] In some possible implementations, in order to effectively analyze and detect the pH value and nickel content of the solution taken by the analysis unit;

[0053] The analysis unit includes a pH probe and a nickel probe for extracting the solution taken by the sampling unit, and an analysis module connected to the pH probe and the detection probe and used for analyzing and detecting the pH value and the nickel content; the analysis module is connected to the control unit, and the solution after analysis and detection flows back to the pre-plating tank through the reflux pipe;

[0054] The analysis unit includes a nickel probe, a pH probe, and an analysis module for nickel content analysis and pH value detection. The analysis module performs online analysis on the tank liquid and sends the analysis and detection results to the control system. The nickel content is analyzed using the photoelectric colorimetry principle, and the pH detection is analyzed using the potentiometric analysis method.

[0055] In some possible implementations, in order to effectively add liquid to the pre-plating tank through the liquid adding unit to adjust the pH value and nickel content of the solution in real time;

[0056] The liquid adding unit includes a tank A storing liquid A, a tank B storing liquid B, a metering pump A connected to a control unit and used for extracting liquid A and adding it to a pre-plating tank, and a metering pump B connected to the control unit and used for extracting liquid B and adding it to the pre-plating tank; the liquid A is a liquid mainly containing nickel sulfate and sodium hypophosphite; the liquid B is a liquid mainly containing ammonia water.

[0057] Both metering pump A and metering pump B are purchased from Japan Iwaki metering pumps; specifically, the amount of alkaline pre-nickel plating concentrate added is adjusted according to the flow rate of metering pump A and the change in concentration value, so that the main salt component of alkaline pre-nickel plating in the solution is within the process requirement range for a long time; the amount of ammonia water added is adjusted according to the flow rate of metering pump B and the change in pH value, so that the pH value in the solution is within the process requirement range for a long time.

[0058] In some possible implementations, in order to discharge the volatile gas in slots A and B in a timely manner;

[0059] The slot A and the slot B are respectively provided with exhaust pipes.

[0060] Furthermore, a liquid level gauge is provided on tank A and tank B respectively; the liquid level gauge is connected to the control system; when the liquid in tank A and tank B is lower than the minimum liquid level line, the control system issues an early warning to prompt adding liquid;

[0061] Specifically, the control system in the present invention is a PLC control system, which uses a programmable logic controller to receive and process the analysis results uploaded by the analysis unit, determine whether the nickel content and pH value in the solution are within the set range, and transmit the analysis results to an external display system. If the analysis result is lower than the set value, the control system automatically controls the liquid adding unit to add liquid A and / or liquid B to the pre-plating tank liquid in real time;

[0062] Furthermore, the analysis and detection of nickel content and pH value are two independent output signals. The data after detection is displayed on the display system and transmitted to the PLC control system at the same time to determine whether the composition of the bath liquid is within the set nickel ion content and pH control line range; if the analysis result is lower than the set control value, the PLC control system issues a corresponding instruction, and the metering pump extracts additive A or additive B and adds it to the plating tank until the nickel ion content and pH value in the plating solution reach the set value.

[0063] Embodiment 2:

[0064] A maintenance method for an alkaline pre-nickel plating solution maintenance system according to the above-mentioned method specifically comprises the following steps:

[0065] Step S1: The sampling unit samples the solution from the pre-plating tank and transports it to the analysis unit;

[0066] Specifically, the sampling pump is started, and the solution flows from the pre-plating tank into the liquid collection tube, and enters the analysis unit after being cooled, filtered, and defoamed.

[0067] Step S2: The analysis unit detects the pH value and nickel content of the solution, and transmits the analysis and detection data to the control unit, and the solution after analysis and detection flows back to the pre-plating tank;

[0068] After defoaming by the defoamer, the solution flows into the pH probe and the nickel probe in turn. The pH value is detected by electrode potential method, and the nickel ion content is detected by photoelectric colorimetry principle and circuit signal principle. The analyzed plating solution flows back to the alkaline chemical pre-nickel plating tank through the reflux pipe to reduce the waste of plating solution.

[0069] Step S3: The control unit controls the liquid adding unit to add liquid A and / or liquid B to the pre-plating tank according to the analysis and detection data until the nickel content and pH value in the solution reach the set values ​​respectively; the step S3 specifically refers to:

[0070] The control system receives and processes the pH value data and the nickel content data, determines whether the nickel content and the pH value in the solution are within the set range, and transmits the analysis results to the display system connected to the control system;

[0071] If the analysis result is lower than the set value, the control system controls the liquid adding unit to add liquid A and / or liquid B into the pre-plating tank to adjust the nickel content and pH value of the solution in real time.

[0072] Based on the above maintenance system and maintenance method, and the chemical titration analysis method in the prior art, the nickel content and pH value of the pre-nickel plating tank solution of the chemical nickel plating production line in normal automated batch production are analyzed, detected, adjusted and monitored using the chemical titration analysis method in the prior art and the present invention respectively;

[0073] Among them, the nickel content and pH value maintenance results of the plating solution by the method of chemical titration analysis and manual supplementation adjustment in the prior art are shown in Table 1; the nickel content and pH value maintenance results of the chemical pre-nickel plating solution by the present invention are shown in Table 2, and the automatic analysis and chemical titration analysis results of the present invention are also compared, see Table 2;

[0074] Comparing the data in Table 1 and Table 2, it can be seen that the composition of the alkaline pre-nickel plating solution controlled by the present invention is more stable than that by the chemical titration analysis and manual addition method.

[0075]

[0076]

[0077] Table 1

[0078]

[0079] Table 2

[0080] It can be clearly seen that the online automatic analysis of the present invention has good effect and accurate analysis, can effectively control the main salt composition of alkaline pre-nickel plating to be within the process requirements for a long time, and no bonding problems have occurred in chemical nickel plating production for more than 6 months, meeting the needs of automated mass production.

[0081] The present invention can accurately and timely monitor the nickel ion content and pH value in the alkaline pre-nickel plating solution online, and can automatically and timely add and adjust the main components and pH value in the alkaline pre-nickel plating solution to make them fluctuate within a smaller range, thereby improving its process stability, adapting to the batch production of the aluminum alloy chemical nickel plating automated production line, and effectively ensuring the stable quality of the aluminum alloy chemical nickel plating layer.

[0082] The present invention is not limited to the above-mentioned specific embodiments, but extends to any new features or any new combination disclosed in this specification, as well as any new method or process steps or any new combination disclosed.

Claims

1. An alkaline nickel pre-plating solution maintenance system, used in conjunction with a pre-plating tank, characterized in that: The invention comprises a sampling unit for sampling the solution in the pre-plating tank, an analyzing unit for analyzing the solution taken by the sampling unit, a control unit connected to the analyzing unit and the sampling unit, and a liquid adding unit connected to the control unit and used for adding liquid to the pre-plating tank; the control unit controls the liquid adding unit to add liquid to the pre-plating tank according to the analysis data provided by the analyzing unit, so that the plating solution in the pre-plating tank is within the process requirement range.

2. An alkaline pre-nickel plating solution maintenance system according to claim 1, characterized in that: The sampling unit comprises a sampling tube connected to the pre-plating tank, a filter, a sampling pump and a defoamer sequentially installed on the sampling tube, and the defoamer is arranged at one end of the sampling tube close to the analysis unit.

3. An alkaline pre-nickel plating solution maintenance system according to claim 2, characterized in that: The sampling unit also includes a radiator which is arranged on the sampling tube and located between the filter and the pre-plating tank.

4. The alkaline pre-nickel plating solution maintenance system according to claim 1, characterized in that: The analysis unit includes a pH probe and a nickel probe for extracting the solution taken by the sampling unit, and an analysis module connected to the pH probe and the detection probe and used for analyzing and detecting the pH value and the nickel content; the analysis module is connected to the control unit, and the solution after analysis and detection flows back to the pre-plating tank through the reflux pipe.

5. The alkaline pre-nickel plating solution maintenance system according to claim 1, characterized in that: The liquid adding unit includes a tank A storing liquid A, a tank B storing liquid B, a metering pump A connected to a control unit and used for extracting liquid A and adding it to a pre-plating tank, and a metering pump B connected to the control unit and used for extracting liquid B and adding it to the pre-plating tank; the liquid A is a liquid mainly containing nickel sulfate and sodium hypophosphite; the liquid B is a liquid mainly containing ammonia water.

6. An alkaline pre-nickel plating solution maintenance system according to claim 5, characterized in that: The slot A and the slot B are respectively provided with exhaust pipes.

7. A maintenance method for an alkaline pre-nickel plating solution maintenance system according to any one of claims 1 to 6, characterized in that: The specific steps include: Step S1: The sampling unit samples the solution from the pre-plating tank and transports it to the analysis unit; Step S2: The analysis unit detects the pH value and nickel content of the solution, and transmits the analysis and detection data to the control unit, and the solution after analysis and detection flows back to the pre-plating tank; Step S3: The control unit controls the liquid adding unit to add liquid A and / or liquid B into the pre-plating tank according to the analysis and detection data until the nickel content and pH value in the solution reach the set values ​​respectively.

8. The maintenance method of an alkaline pre-nickel plating solution maintenance system according to claim 7, characterized in that: The step S1 specifically refers to: the sampling pump is started, the solution flows from the pre-plating tank into the liquid collection tube, and enters the analysis unit after being cooled, filtered, and defoamed.

9. The maintenance method of an alkaline pre-nickel plating solution maintenance system according to claim 7, characterized in that: The step S2 specifically refers to: The pH probe extracts the solution, and the analysis module uses potentiometric analysis to analyze the pH value of the test solution and transmits the pH value data to the control system; The nickel probe extracts the solution, and the analysis module uses the photoelectric colorimetric principle to analyze the nickel content in the solution and sends the nickel content data to the control system; The solution after analysis and detection flows back into the pre-plating tank through the reflux pipe.

10. The maintenance method of an alkaline pre-nickel plating solution maintenance system according to claim 7, characterized in that: The step S3 specifically refers to: The control system receives and processes the pH value data and the nickel content data, determines whether the nickel content and the pH value in the solution are within the set range, and transmits the analysis results to the display system connected to the control system; If the analysis result is lower than the set value, the control system controls the liquid adding unit to add liquid A and / or liquid B into the pre-plating tank to adjust the nickel content and pH value of the solution in real time.

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