Surely in the process of operating the powder coating line, you may encounter a lot of powder coating mistakes as no matter how modern the production line is, it will definitely have some unwanted problems arise after a long time of operation. So in this article, we will share with you the most common powder coating mistakes may happen in processing. Hope this knowledge can help you, if you want to advise or suggest anything, please leave it below in the comment section.
| No. | Phenomena | Causes | Solutions |
| 1 | Powder coating is condensing | 1. Powder may be affected by temperature or humiddity
2. The powder coating is out-of-date 3. The powder can be suppressed. |
1.Stored in cool and dry places, and must be packed carefully
2.Use within the time allowed 3. Paint containers must be sturdy |
| 2 | Paint sprayed from the gun unevenly | 1. The spray gun has defective
2. Insufficient and stable gas pressure 3. Powder coating duct is too long |
1.Check if the spray gun has any powder clogging
2.Stabilize and increase gas pressure 3.Reduce the length of powder coated duct |
| 3 | The spray device is clogged | 1.Powder is clumped due to external environment
2.Powder is cured at the top of the sprayer 3. Insufficient compressed air pressure |
1. Filter the powder
2.Clean the injector regularly 3.Increase the pressure of the powder-carring gas |
| 4 | Paint does not stick to the product | 1. Output voltage is not suitable
2. Too much air pressure 3. Do not clean the surface of the product 4. Bad mass connection |
1.Increase output voltage
2. Adjust gas pressure 3.Products are carefully cleaned 4. Check mass connection |
| 5 | Paint is hovering everywhere | 1. Filter bag does not absorb powder paint
2.Occlusion in the discharge pipe 3.Exhaust gas pressure exceeds the allowable level |
1.Check the dust filter bag
2.Unblock the exhaust column 3. Adjust the gas pressure. |
| 6 | Electrostatic Discharge Coatings | 1. Mass connection is improper.
2. The distance between products and spray equipment is closer than specified level 3.High powder coating density 4. Impedance of injection device exceeds specified level |
1. Check earthing system
2. Creat a gap between the product and the nozzle 3. Reduce powder injection pressure and test vortex gas 4. Impedance is changed |
| 7 | Powder floating on the surface | 1. Bad fretreatment for the surface of materials
2. Oversprayed powder can be used too much |
1.Clean the product surface
2.New powder and oversprayed powder should be mixed together |
| 8 | Clumping on the surface | High electrostatic spraying rate causes thick layers. | Reduce the paint thickness. |
| 9 | Orange peel | 1. Spray pressure is redundant
2.Uneven paint coverage 3.Paint powder is clumped |
1.Improve pray painting skills
2.Avoid powder clumping and adjust the spray level of the spray devices. |
| 10 | Imperfect color | 1.The drying time is too long or too short, the heating temperature is too high or too low
2. Heat of furnaces |
1. Adjust the correct level to the drying temperature of each paint
2.Check heating appliances or gas stoves |
| 11 | Unevenness of colors | 1.Gap of spray devices and products is too close
2. High voltage of static electricity with unstable voltage 3. Powder coating is lumpy. |
1.Adjust the gap between the product and the spray gun
2.Adjust or replace high voltage 3.Prevent powder from coalescing, sticking together |
| 12 | Paint gloss reduced | 1.Mix 2 types of new powder and oversprayed powder together
2.Mix powders of different manufacturers together |
1.Reduce the oversprayed powder
2. Do not mix or limit mixing of diferent types of powder |
| 13 | Pinhole | 1.High output voltage
2.Gap between product and spray equipment is close 3. Coating thickness |
1.Reduce electrostatic voltage
2.Adjust the gap properly 3.Control the thickness of the coating |
| 14 | Poor mechanical properties | Lack of drying time or insufficient drying temperature | Notice the drying temperature and drying time of each type of powder and do as prescribed |
| 15 | Surface not fully covered | 1.Oil stains on product surface
2.Product surface is rough 3.Mix different types of powder from different manufacturers |
1.Clean the product surface
2.Polish the surface smoothly 3.Do not mix different types of powders |
| 16 | Bubble | 1.The surface is not completely dry during the cleaning step
2.Product surface is not flat and appears hole |
1.Surface must be clean and dry
2. Do flat surface grinding |
| 17 | Paint is peeling | 1.Do not clean the surface
2. Insufficient drying time 3. Oxidation of product surface |
1. Clean the product surface
2.Drying time must be sufficient depending on the type of products 3.Handle product surface carefully |
Ninh Binh DHA provides a high-quality powder coating service. We apply high-class machines, tools, and have specialists with many years of experience in this industry. We know how to control the powder coating process and avoid or fix powder coating mistakes professionally to provide you with the best quality products.
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Finding a professional powder coating supplier is important. Follow our website to get more useful information and do not hesitate to contact us for consultance and a quote by: Hotline: 0869651843
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