Basic structural components of electroplating equipment

Dec. 07, 2021   |   154 views

1. Potion tank

Generally used materials include PP, PVC and stainless steel. If heating is not required, PVC tank can be used, PP tank can be used when the temperature is below 70 ℃, and stainless steel tank is required when the temperature exceeds 70 ℃, but stainless steel tank (metal tank) is not available for electroplating tank.In continuous electroplating, there are main tank and secondary tank.The main tank is used for charging electroplating solution, and the secondary tank is used for electroplating. At present, there are three ways: separation, homology and sharing.The design of the mother tank structure is relatively simple. Only factors such as water flow, mixing, steady flow, positioning, distance between anode and cathode and so on need to be considered.

2. Base frame of tank

Generally, there are derivative frames of plastic medicine tanks, angle iron, stainless steel square tubes, black iron painting, etc.In order to consider the strength and corrosion resistance, it is recommended to use stainless steel square pipe.

3. Water inlet system

Generally, pure water and tap water are used. A water inlet is arranged on each medicine tank to supplement the water level and clear the tank.In order to avoid water pipe leakage or human negligence, the electroplating tank is not equipped with water inlet device.

4. Drainage system

Generally, drainage shall be classified before setting drainage system.The wastewater from continuous electroplating of terminals is classified as acid solution, alkali solution, nickel solution, gold solution, tin lead solution, etc.It is recommended to use more than one inch of pipe for each tank drain.The drainage effect is good.Generally, the water washing tank is equipped with a single drain valve, while each electroplating medicine tank is equipped with a double drain valve to avoid human negligence to drain the medicine.Overflow pipes shall be set for each tank to avoid full water flow to other tanks.

5. Exhaust system

The electroplating equipment needs to be sealed (i.e. with an upper cover) to have the effect of exhaust. An air outlet is set in the medicine tank that mainly produces waste gas, and the air extraction volume can be adjusted.Due to the high water content in the gas, a drainage device shall be set.The extracted gas must also be treated as waste gas.

6. Electric heating system

Because the medicine tank needs to be heated, the heating system is very important.The general heating system consists of heater, temperature sensor, liquid level sensor, temperature setter, timer, alarm, etc. Considering the safety problem, it is necessary to set up a water free automatic power-off system.Titanium is the longest used material immersed in the liquid medicine, but in the strong alkali medicine tank, it is recommended to use stainless steel or Teflon.

7. Cooling system

Generally, there are direct freezing method and indirect freezing method.The direct freezing method is to pump the liquid medicine into the refrigerator for cooling. This method has good freezing effect.The indirect freezing method is to indirectly freeze the liquid medicine by discharging the cooling water pipe in the liquid medicine tank. This method has poor freezing effect and is difficult to clean the tank.The cooling methods of the refrigerator include water cooling method (cooling tower) and air cooling method (fan).If the tin lead potion can be kept at a low temperature for 24 hours, the potion will not cause turbidity.

8. Electric control system

In addition to the electric control of the above heating and cooling system, there are also electric controls of pumps, filters, oscillators, rectifiers, drives, ovens, blowers, etc., which are usually controlled by the power control box.The rectifier and transmission are set as interlocking devices.

9. Wiper equipment

In continuous electroplating equipment, the scraping methods include rubber scraper, brush, air blowing, water absorption sponge and so on.Among them, the blowing method has the best effect, but the cost is the highest. At present, the blowing generation methods include air compressor generation and blower generation.The terminal with poor structure (easy to deform) is not suitable for brush and scraper, and the silicone rubber scraper is suitable for flat terminals.

10. Drying system

After electroplating, the water droplets on the terminal surface must be removed, otherwise the drying effect will be very poor.Generally, the drying oven uses heater or IR and is dried under hot air circulation.The oven must have a temperature control device.

11. Feeding system

Generally, there are horizontal and vertical feeding methods.The discharge area is equipped with a paper winding device, a linkage switch and a positioning guide wheel.If the production speed is very fast, buffer wiring shall be set.

12. Receiving system

The general receiving methods are horizontal and vertical.The receiving area shall be equipped with transmission device (some special transmission devices are not in the receiving system), counting device, linkage switch, receiving device, paper rotary table and positioning guide wheel. If the production speed is very fast, buffer wiring shall be set.

13. Pump filter

 It is generally divided into horizontal pump and vertical pump. Its specifications are distinguished by HP horsepower. The greater the horsepower, the greater the flow. The common specifications of filter elements are 1 µ, 5 µ and 10 µ. The smaller the number of µ, the smaller the filterable particles, and the better the filtering effect.It is generally recommended to use 1 µ for gold tank, palladium nickel tank and 5 µ filter element for others, and check regularly every week.The longer the filtering time, the better the effect. It is best to filter for 24 hours.

14. Rectifier

At present, there are controllable silicon rectifier, electro crystal rectifier, frequency conversion rectifier, pulse rectifier, etc. Because the DC wave degree will affect the current density range, the smaller the filter degree, the wider the operable current density. Generally, the filter degree must be less than 3%. Among them, the frequency conversion rectifier is the best, and the filtering degree is about 0.1%.

15. Positioner

 Generally, the methods used in the medicine tank include fixed type (for full immersion) and adjustment type (for selective plating or considering current distribution), and the materials used include acid-base and heat-resistant plastics, glass, ceramics, etc. As for the positioner outside the medicine tank, stainless steel is mostly used.

16. Anode and cathode

The specification of cathode (anode) conductive wire is maximum operating current / 4 * (number of wires).If the current is 100 amps and there are two conductors, the cross section of the conductor needs to be at least 12.5 mm

Anode can be divided into soluble anode and insoluble anode.Soluble anodes are used for supplement (common in common metal electroplating), while insoluble anodes are used as auxiliary anodes. For example, when nickel plating, nickel metal is used as soluble anode, and titanium basket is used to contain nickel metal, so it is insoluble anode.Insoluble anodes (such as platinum) are usually used for noble metal electroplating because of their good conductivity.The cathode generally refers to the plated part, but the cathode described here is the cathode conductive head for the conduction of the plated part. Generally, the cathode conductive head uses copper alloy or stainless steel material. The material can be determined only after considering conductivity, corrosion resistance, operation and cost.The cathode conductive head shall be in good contact with the plated part, and the smaller the friction, the better.

17. Agitator

 In order to promote electroplating efficiency, increase electroplating uniformity and improve current density, the stirring effect must be strengthened.Generally, strong water flow stirring, cathode vibration stirring, ultrasonic stirring, air stirring and other methods are used.