PCBA Tech - How to wash pcba

After the PCBA processing process is completed, it is often seen that there will be many residues on the surface of the PCBA. These residues not only affect the appearance, but also affect the quality of the PCBA. Therefore, the cleaning of the PCBA is very important. Next, I will introduce manual cleaning. And automatic cleaning method.

1, PCBA manual cleaning
General small and medium-sized PCBA processing plants will use manual cleaning methods, the cleaning cost is low, and it is relatively cost-effective. Manual cleaning tools mainly include: cleaning tank, spray cans, brushes, IPA or VIGON EFM, gloves, deionized water, wipe paper, air guns, and sealed bags.

Manual cleaning steps:

1. Clean the PCB circuit board in IPA or VIGON EFM, or spray IPA and EFM on the surface of the circuit board, using about 10ml per 4 square inches.

2. Use a moist soft short-bristled brush to wipe the circuit board continuously for about 10 seconds.

3. Use deionized water for rinsing, about 10 ml per 4 square inches. Effectively remove potential pollutant residues.

4. Hold the edge of the circuit board and wipe off the excess deionized water with a clean lint-free wipe.

5. Visually inspect the cleanliness of the PCBA circuit board.

6. If necessary, use an air gun to dry the circuit board.

7. If the circuit board or components need to be stored for a period of time before coating, please put the circuit board or components in a sealed bag containing a desiccant.

Automatic cleaning

Automatic cleaning process is divided into three methods: water cleaning, semi-aqueous cleaning and solvent cleaning.

Automatic cleaning tools and materials mainly include: water cleaning machine, deionized water system, conductivity tester, beaker, deionized water.

Automatic cleaning operation steps:

1. Preparation of deionized water: use an electrodialysis device and an ion exchange resin tank to prepare deionized water.

2. Conductivity test: Use a conductivity tester to test the conductivity of the water after electrodialysis and ion exchange resin tanks. If all meet the index requirements, it can be used for water cleaning.

3. Introduce the water washing machine: introduce the deionized water in the water storage tank to the water washing machine.

4. Set the washing machine parameters: the washing room and rinsing room are set at 60±10 degree Celsius; the drying room is set at 60 degree Celsius～90 degree Celsius.

5. Setting the chain speed: generally control the chain speed at 50～150cm/min.

6. After the PCBA is cleaned, take it out from the washing machine and store it in an anti-static turnover container. The anti-static turnover container is required to be clean and dust-free to avoid secondary pollution of the PCBA after cleaning.