What is the Cause of Coating Shrinkage? How to Solve It?
Various problems may occur during electrostatic powder spraying. The coating shrinkage is one of them. So, when we encounter the coating shrinkage cavity, how should we deal with it?
In the face of coating shrinkage, we should first clear up the thinking, find out several causes of coating shrinkage, and then find corresponding solutions according to the causes. Several reasons and solutions for coating shrinkage are attached as follows:
(1) Shrinkage caused by residual surfactant due to unclean pretreatment and oil removal or unclean water washing after oil removal
Solution: control the concentration and proportion of pre degreasing tank and degreasing tank, reduce the oil content of workpiece and strengthen the effect of water washing.
(2) Water quality shrinkage caused by excessive oil content
Solution: add water inlet filter to prevent oil leakage of water supply pump.
(3) Shrinkage caused by excessive water content of compressed air
Solution: discharge compressed air condensate in time.
(4) Shrinkage caused by moisture in the powder.
Solution: improve the storage and transportation conditions of powder, add dehumidifier to ensure the timely use of recovered powder
(5) The oil on the suspension chain is blown to the workpiece by the air conditioning wind and causes shrinkage.
Solution: change the position and direction of air supply outlet.
(6) Shrinkage caused by mixing powder.
Solution: clean the powder spraying system thoroughly when changing powder.
AEM Deposition, as a professional powder supplier, can provide all kinds of pure metal powder. Such as chromium powder, hafnium powder, molybdenum powder and so on. Interested friends can click the link below to go to the product page to learn more!