A plating tank variable frequency circulation filtering control system and a control method thereof

Abstract

The application provides a plating tank variable-frequency circulation filtering control system and a control method thereof. The variable-frequency circulation equipment is controlled by a frequency converter. When the loading capacity of the product entering the plating tank does not meet the requirements, the plating solution circulation capacity is controllable, the phenomenon of "plating inhibition" of the plating layer caused by circulation impact is effectively reduced, the product qualified rate and quality reliability are improved, and the demand of high-quality development of military electrical connector products is met.

Description

Technical Field

[0001] This invention relates to a frequency conversion circulating filtration control system for plating tanks and its control method. Background Technology

[0002] High-phosphorus electroless nickel plating is widely used in weaponry due to the good stability of the plating solution and the high corrosion resistance and non-magnetic properties of the coating. It is applied to substrate materials including metals (aluminum alloys, copper alloys, magnesium alloys, etc.) and non-metals (plastic parts, ceramic parts, etc.). A good high-phosphorus electroless nickel plating formula and a circulating filtration system are key processes and equipment in the electroless nickel plating production process. The production process of high-phosphorus electroless nickel plating for connector aluminum alloys is as follows: Obtain an optimal plating solution formula; weigh and stir relevant materials to form a solution; prepare the required solution according to the formula ratio; passivate the stainless steel tank with nitric acid and then clean it; pour the prepared solution into the tank; replenish the plating tank with pure water; adjust the plating solution temperature and pH to within the process parameter range; and start the circulating filtration to produce a nickel-phosphorus alloy plating product of a certain thickness. The original production process of the current automated electroless nickel plating production line is: First, material inspection in the loading area; second, material unloading by the overhead crane; third, material reaching the plating tank; fourth, material unloading by the overhead crane; fifth, product plating.

[0003] The circulating filtration equipment is mainly designed for the chemical nickel plating process, which involves numerous side reactions. The resulting microparticles need to be filtered through this system in a timely manner to ensure that the plating solution is free of obvious impurities and that the plating layer does not produce particulate matter.

[0004] However, in actual production, due to the inconsistent production area of ​​each plating tank caused by the size of the connector parts, the loading capacity often fails to meet the optimal process requirements. Furthermore, the loading capacity increases sequentially over a certain period during production. Therefore, the loading capacity only approaches the optimal process value when all parts are fully immersed in the plating tank. Throughout the production process, the circulation system remains unchanged, resulting in a small loading capacity when the first batch of parts enters the plating tank. This leads to low plating solution activity, and the large circulation volume directly impacts the part surface, causing insufficient activity at edges and resulting in product quality issues. For example, CN114703524A discloses a flow control method and system for a chemical nickel filter based on an electroplating line. This method classifies the operating parameters of different chemical nickel filters, and the control system starts the filter via a first-stage start signal and switches the flow rate of the chemical nickel filter via a second-stage start signal. This automatic flow frequency conversion switching control optimizes and balances plating defects and reduces impurities. It sets different frequencies during startup and nickel plating, and the frequency during material transportation is the same as the frequency during nickel plating, which reduces the speed of material transportation and reduces production efficiency. Summary of the Invention

[0005] To solve the above-mentioned technical problems, the present invention provides a frequency conversion circulating filtration control system for plating tanks and its control method.

[0006] The present invention is achieved through the following technical solutions.

[0007] The present invention provides a frequency conversion circulating filtration control system and control method for a plating tank, comprising the following steps:

[0008] S1. After startup, the PLC detects the materials in the feeding area;

[0009] S2. If material is detected, control the crane to pick up the material from the loading area and transfer it to the top of the plating tank;

[0010] S3. When the detection switch A detects that the material has arrived above the plating tank, it sends the material position A signal to the PLC.

[0011] S4, PLC output frequency adjustment command to control the frequency converter to adjust the frequency to 15Hz to control the crane to lower the material.

[0012] S5. After the detection switch B detects that the material has entered the plating tank, it sends the material position signal B to the PLC.

[0013] S6, PLC outputs frequency adjustment command to control the frequency converter to adjust the frequency to 50Hz and start timing;

[0014] S7. The plating tank is powered on to perform chemical plating on the material. After the timing ends, the frequency converter is adjusted to 15Hz to control the crane to rise and remove the material.

[0015] S8 and PLC control the crane to unload materials into the storage area;

[0016] S9. Repeat steps S1-S8 until the material is chemically plated.

[0017] In step S1, material detection is performed using image recognition.

[0018] Both detection switch A and detection switch B are proximity switches.

[0019] In step S6, the timing time is 300s to 500s.

[0020] A variable frequency circulating filtration control system for plating tanks includes a PLC and a frequency converter. The PLC's Y010, Y011, and COM3 ports are connected to the frequency converter's STF, STR, and SD ports, respectively. The PLC's X000 and X001 ports are connected to a power-on push-button switch SB1 and a power-off push-button switch SB2, respectively. The other ends of the power-on and power-off push-button switches SB1 and SB2 are connected to the frequency converter's A port. The PLC's X002 and X003 ports are connected to the two stationary contacts of a single-pole double-throw switch SA, respectively. The moving contact of the single-pole double-throw switch SA and the PLC's COM port are connected to the frequency converter's A port. The PLC's X004 port is connected to the frequency converter's C port. The PLC's Y000 port is connected to the coil of a relay KM. The other end of the relay KM coil and the PLC's COM1 port are connected to the positive and negative terminals of a 220V AC power supply, respectively.

[0021] The Y001, Y002, and Y003 ports of the PLC are respectively connected to the power indicator HL1, forward indicator HL2, and reverse indicator HL3. The other end of the power indicator HL1, forward indicator HL2, and reverse indicator HL3 is connected to the positive terminal of 220V AC power.

[0022] The Y004 port of the PLC is also connected to the inverter fault indicator HL4, and the other end of the inverter fault indicator HL4 and the COM2 port of the PLC are respectively connected to the positive and negative terminals of 220V AC power.

[0023] The beneficial effects of this invention are as follows: by using a frequency converter to control the circulation equipment, when the loading amount of the product entering the plating tank does not meet the requirements, the circulation amount of the plating solution can be controlled, which effectively reduces the "plating suppression" phenomenon caused by the circulatory impact, improves the product qualification rate and quality reliability, and meets the needs of high-quality development of military electrical connector products. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of the present invention. Detailed Implementation

[0025] The technical solution of the present invention is further described below, but the scope of protection is not limited to what is described.

[0026] A variable frequency circulating filtration control system and its control method for a plating tank include the following steps:

[0027] S1. After startup, the PLC detects the materials in the feeding area;

[0028] S2. If material is detected, control the crane to pick up the material from the loading area and transfer it to the top of the plating tank;

[0029] S3. When the detection switch A detects that the material has arrived above the plating tank, it sends the material position A signal to the PLC.

[0030] S4, PLC output frequency adjustment command to control the frequency converter to adjust the frequency to 15Hz to control the crane to lower the material.

[0031] S5. After the detection switch B detects that the material has entered the plating tank, it sends the material position signal B to the PLC.

[0032] S6, PLC outputs frequency adjustment command to control the frequency converter to adjust the frequency to 50Hz and start timing;

[0033] S7. The plating tank is powered on to perform chemical plating on the material. After the timing ends, the frequency converter is adjusted to 15Hz to control the crane to rise and remove the material.

[0034] S8 and PLC control the crane to unload materials into the storage area;

[0035] S9. Repeat steps S1-S8 until the material is chemically plated.

[0036] In step S1, material detection is performed using image recognition.

[0037] Both detection switch A and detection switch B are proximity switches.

[0038] In step S6, the timing time is 300s to 500s.

[0039] A variable frequency circulating filtration control system for plating tanks includes a PLC and a frequency converter. The PLC's Y010, Y011, and COM3 ports are connected to the frequency converter's STF, STR, and SD ports, respectively. The PLC's X000 and X001 ports are connected to a power-on push-button switch SB1 and a power-off push-button switch SB2, respectively. The other ends of the power-on and power-off push-button switches SB1 and SB2 are connected to the frequency converter's A port. The PLC's X002 and X003 ports are connected to the two stationary contacts of a single-pole double-throw switch SA, respectively. The moving contact of the single-pole double-throw switch SA and the PLC's COM port are connected to the frequency converter's A port. The PLC's X004 port is connected to the frequency converter's C port. The PLC's Y000 port is connected to the coil of a relay KM. The other end of the relay KM coil and the PLC's COM1 port are connected to the positive and negative terminals of a 220V AC power supply, respectively.

[0040] The Y001, Y002, and Y003 ports of the PLC are respectively connected to the power indicator HL1, forward indicator HL2, and reverse indicator HL3. The other end of the power indicator HL1, forward indicator HL2, and reverse indicator HL3 is connected to the positive terminal of 220V AC power.

[0041] The Y004 port of the PLC is also connected to the inverter fault indicator HL4, and the other end of the inverter fault indicator HL4 and the COM2 port of the PLC are respectively connected to the positive and negative terminals of 220V AC power.

[0042] This invention solves the problem of ensuring controllable production process by controlling the circulation volume through frequency conversion when the loading volume does not meet the optimal process value. It also addresses the issue that the circulation volume cannot be arbitrarily adjusted during production, which can lead to insufficient edge activity of the product after it enters the plating tank due to the influence of the circulation volume, resulting in "plating suppression" and low product qualification rate.

Claims

1. A method for controlling the variable frequency circulating filtration of a plating tank, the variable frequency circulating filtration control system comprising a PLC and a frequency converter, wherein the Y010, Y011, and COM3 ports of the PLC are respectively connected to the STF, STR, and SD ports of the frequency converter; the X000 and X001 ports of the PLC are respectively connected to a power-on button switch SB1 and a power-off button switch SB2; the other ends of the power-on button switch SB1 and the power-off button switch SB2 are connected to the A port of the frequency converter; the X002 and X003 ports of the PLC are respectively connected to the two stationary contacts of a single-pole double-throw switch SA; the moving contact of the single-pole double-throw switch SA and the COM port of the PLC are connected to the A port of the frequency converter; the X004 port of the PLC is connected to the C port of the frequency converter; the Y000 port of the PLC is connected to the coil of a relay KM; the other end of the coil of the relay KM and the COM1 port of the PLC are respectively connected to the positive and negative terminals of a 220V AC power supply. The Y001, Y002, and Y003 ports of the PLC are respectively connected to the power indicator HL1, forward indicator HL2, and reverse indicator HL3. The other end of the power indicator HL1, forward indicator HL2, and reverse indicator HL3 is connected to the positive terminal of 220V AC power. The Y004 port of the PLC is also connected to the inverter fault indicator HL4, and the other end of the inverter fault indicator HL4 and the COM2 port of the PLC are respectively connected to the positive and negative terminals of 220V AC power. Its features are, The cyclic filtration control method includes the following steps: S1. After startup, the PLC detects the materials in the feeding area; S2. If material is detected, control the crane to pick up the material from the loading area and transfer it to the top of the plating tank; S3. When the detection switch A detects that the material has arrived above the plating tank, it sends the material position A signal to the PLC. S4, PLC output frequency adjustment command to control the frequency converter to adjust the frequency to 15Hz to control the crane to lower the material. S5. After the detection switch B detects that the material has entered the plating tank, it sends the material position signal B to the PLC. S6 and PLC output frequency adjustment commands to control the frequency converter to adjust the frequency to 50Hz and start timing; S7. The plating tank is powered on to perform chemical plating on the material. After the timing ends, the frequency converter is adjusted to 15Hz to control the crane to rise and remove the material. S8 and PLC control the crane to unload materials into the storage area; S9. Repeat steps S1-S8 until the chemical plating of the material is complete; In step S6, the timing time is 300s~500s.

2. The frequency conversion circulation filtration control method for plating tanks as described in claim 1, characterized in that: In step S1, material detection is performed using image recognition.

3. The frequency conversion circulation filtration control method for plating tanks as described in claim 1, characterized in that: Both detection switch A and detection switch B are proximity switches.

Images