The PCBA water cleaning process uses water as the cleaning medium. Small amounts (usually 2% to 10%) of surfactants, corrosion inhibitors and other chemicals can be added to the water. By cleaning, PCBA cleaning is through multi-source cleaning and drying with pure or deionized water. So today, the editor will introduce the principle and advantages and disadvantages of PCBA water cleaning technology to you. Let's take a look!

The advantage of water washing is that the cleaning medium of water washing is generally non-toxic, does not harm the health of workers, is non-flammable, non-explosive, and has good safety. Water washing has a good cleaning effect on particulate matter, rosin flux, water-soluble pollutants and polar pollutants: water washing has good compatibility with component packaging materials and PCB materials, and will not cause rubber parts and coatings. . Expansion does not crack, keeps the marks and symbols on the surface of the part clear and complete, and will not be washed away. Therefore, water cleaning is one of the main processes for non-ODS cleaning.

The disadvantage of water washing is that the investment of the entire equipment is large, and the water production equipment of pure water or deionized water is also invested. In addition, it is not suitable for non-hermetic devices, such as adjustable potentiometers, inductors, switches, etc., the water vapor entering the device is not easy to discharge, and even damages the ring element.

Washing technology can be divided into pure water washing and water plus surfactant washing. The typical PCBA process flow is as follows: water + surfactant → water → pure water → ultrapure water → hot air washing → rinsing → drying.

In general, an ultrasonic device is added in the cleaning stage. In addition to the ultrasonic device, an air knife (nozzle) device is also added in the cleaning stage. The water temperature should be controlled at 60-70℃, the water quality should be very high, and the resistivity should be 8-18mq?

CM, an alternative technology, is suitable for companies that have high requirements for mass production and product reliability in SMT chip processing plants. For small batch cleaning, small cleaning equipment can be selected.