The maintenance and management of electrophoretic bath solution is an important task in the construction process of electrophoretic coating. The quality of management not only affects the construction quality, but also directly affects the stability of electrophoretic coating solution.
1) Management of objects to be coated
a. Frequently check whether the hanging of the coated object meets the process requirements, and ensure that the hanging fixture and electrodes are well conductive.
b. Check the quality of the pre-painting treatment, the treatment film should be uniform, and the surface should be free of oil and rust; the pH value and conductivity of the water (or accumulated water) of the coated object should be checked frequently (or the final the quality of a wash water).
c. Record the quantity and area of the object to be coated.
2) Management of electrophoresis tank and electrophoresis tank solution
a. Pay attention to whether the stirring, temperature control system and anode liquid circulation system are operating normally.
b. Regularly measure the solid content of the tank liquid, and add paint and additives in a timely and appropriate manner according to the amount of paint in the tank and the measured value.
c. Keep the working environment clean to prevent dust and impurities from being brought into the working coating solution. Generally, the bottom of the tank is cleaned every 3 months. During production, the doors and windows of the electrophoresis tank are closed. Prevent dust, etc. from getting mixed in.
d. Regularly measure the pH value and conductivity of the bath solution, usually once a day or every shift, and adjust in time.
e. Measure the Coulombic efficiency frequently and compare it with the Coulombic efficiency when the tank is initially configured.
f. Check the energization conditions at any time, such as voltage, current, etc., to know whether the specified conditions are met in time. If the current density is found to be abnormal, check whether the solid content, pH value, temperature and conductivity of the bath are normal, and then check again. Check whether the paint has deteriorated;
g. Measure and study the pigment-base ratio in the solid content of the bath liquid. If it is found to be very different from the original paint, it should be adjusted in time.
h. Regularly measure the penetration force under construction conditions, check the changes during operation, and find out the reasons in time according to the factors that affect the penetration force.
3) Management of coating film quality
a. Regularly check the uniformity and film thickness of the coating film to confirm whether it meets the specified conditions.
b. Check the appearance of the coating film at any time, and there should be no pinholes and flow marks.
c. Regularly test the properties of the coating film, such as adhesion force, corrosion resistance and heat and humidity resistance, etc.
