3 Common Problems about Powder Coatings

March 31,2022

Powder coatings are solid powder synthetic resin coatings composed of solid resins, pigments, fillers and additives. It is widely used in automobile manufacturing. But, do you know what common problems it has? We've summed up a few, and we've also given you a solution.

 

Powder Coatings

 

Discoloration of paint film

 

📌Causes:

 

  1. There is residual treatment liquid on the surface of the coating;

 

  1. Excessive baking, or volatile gas in the oven;

 

  1. Mix powder of other colors during construction;

 

  1. The pigment of the powder itself is not resistant to high temperature or the resin is easy to yellow;

 

📌Solutions:

 

  1. Improve the pretreatment method;

 

  1. Formulate proper baking conditions and purify the oven;

 

  1. Strengthen the cleaning before construction;

 

  1. Replace the qualified powder coating;

 

There are particles on the surface of the coating film

 

📌Causes:

 

  1. The surface of the coated workpiece is not clean;

 

  1. The powder supply is uneven, and the spray gun is not well atomized;

 

  1. The powder is too fine or the powder is wet and agglomerated, causing the spray gun to accumulate powder;

 

  1. The coating site is not clean or there is powder dripping in the spray chamber;

 

  1. The recovered powder or the powder itself is of poor quality;

 

📌Solutions:

 

  1. Improve the quality of the workpiece substrate and strengthen the pretreatment;

 

  1. Adjust the air pressure, check the deflector, and adjust to the best point;

 

  1. Control the particle size distribution of the powder, keep the powder properly, and prevent it from getting wet;

 

  1. Clean up the site and purify the air;

 

  1. After sieving the recovered powder, mix the new powder and replace the qualified powder;

 

Loss of gloss on the coating surface

 

📌Causes:

 

  1. The pretreatment quality of the substrate is poor;

 

  1. The baking time is too long or the temperature is too high;

 

  1. There is volatile gas in the furnace;

 

  1. The proportion of recycled powder is too large;

 

  1. Two powders of different properties are mixed;

 

  1. Poor quality powder coating;

 

📌Solutions:

 

  1. Select the appropriate pretreatment process;

 

  1. Adjust the appropriate curing conditions;

 

  1. Purify the oven;

 

  1. The recovered powder is filtered and mixed with the new powder, preferably <30%;

 

  1. Thoroughly clean the powder spraying system before changing the powder;

 

  1. Replace the powder with good quality;

 

In conclusion

 

Hope the above content can give you some substantial help, if you need more information, please feel free to contact us.

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