常见问题解析Paint film discoloration

一、漆膜变色 Paint film discoloration

产生原因：1.被涂料表面有残留的处理液。2.过度烘烤，或炉内有挥发性气体。3.施工中混入其它颜色的粉料。4.粉末本身的颜料不耐高温或树脂易泛黄。

解决办法：1.改进前处理方法。2.制定适当的烘烤条件。净化烘烤炉。3.加强施工前的清理。4.更换合格的粉末涂料。

The reasons causing: 1. There is residual treatment solution on the surface of the coating. 2. Excessive baking, or volatile gas in the furnace. 3. Mix other colors of powder in construction. 4. The pigment of the powder itself is not resistant to high temperature or resin is easy to yellow.

The solution: 1. Improve the pre-treatment method. 2. Develop appropriate baking conditions and purify the baking oven. 3. Strengthen the cleaning before construction. 4. Replace qualified powder coating.

二、涂膜表面有颗粒疙瘩 The coating surface has a particle knot

产生原因：1.被涂工件表面不干净。2.供粉不均，喷枪雾化不好。3.粉末太细或粉末受潮结团，使喷枪积粉。4.涂装现场不干净或喷室内有粉末滴落。5.回收粉末或粉末本身质量差。

解决办法：1.改善工件底材质量,加强前处理。2.调整空气压力,检查导流器调至佳点。3.控制粉末粒度分布,妥善保管粉末,严防受潮。4.清理现场,净化空气。5.回收粉过筛后新粉混合使用,更换合格的粉末。

Causes: 1. The surface of the coated workpiece is not clean. 2. Uneven powder supply and poor atomization of spray gun. 3. The powder is too fine or the powder is affected with damp and agglomerates, making the spray gun powder. 4. There is no powder dripping in the painting site or spray room.5. Recycled powder or powder itself is of poor quality.

The solution: 1. Improve the quality of the workpiece substrate and strengthen the pretreatment. 2. Adjust the air pressure and check the flow guide to the best point. 3. Control the powder size distribution, properly keep the powder and prevent damp. 4. Clean up the site and defrost the air. 5. After sieving the recovered powder, mix the new powder and replace the qualified powder.

三、缩孔Shrinkage cavity

产生原因：1.工件表面有油污。2.压缩空气中含水、油等，导致粉末受污染。3.受灰尘或其它杂质污染。4.粉末涂料本身有污染。

解决办法：1.加强前处理。2.加强涂装前压缩空气的浄化。3.彻底清理环境、更换合格粉末。

Causes: 1. There is oil on the surface of the workpiece. 2. The compressed air contains water, oil and so on. 3. Resulting in powder pollution. 4. The powder coating itself is contaminated

Solutions: 1. Strengthen pretreatment. 2. Strengthen the compressed air before painting. 3. Clean up the environment thoroughly and replace qualified powder.

四、流平差或者橘皮严重 Flow adjustment or orange peel serious

产生原因：1.工件表面粗糙。2.粉末粒子粗、受潮或粉末流平本身差。3.固化温度偏高或偏低。4.涂膜太薄或太厚。5.工件接地不良。6.不同粉末混杂。

解决方法：1.提高工件光洁度。2.选择粒度分布均匀的、流平好的高质量粉末及严防粉末受潮。3.调整适宜的固化条件。4.控制粉末厚度在60-80um。5.定期清理挂具。6.施工前严格清理喷粉系统及场地，避免不同类型或不同厂家的粉末混用。

The reasons causing: 1. Rough surface of workpiece.Coarse powder particles, damp or powder leveling itself poor 3. High or low curing temperature 4. Coating film is too thin or too thick.5. The workpiece is not properly grounded.Mixed with different powders.

The solution: 1. Improve the smoothness of the workpiece.2. Choose the evenly distributed and smooth powder with high quality and prevent the powder from being affected with damp.3. Adjust appropriate curing conditions.4. Control powder thickness at 60-80um.5. Clean the hangers regularly.6. Strictly clean the powder spraying system and site before construction to avoid mixing powder from different types or manufacturers.

五、涂膜表面失光 Coating surface loss of light

产生原因：1.底材前处理质量差。2.烘烤时间过长或温度过高。3.炉内有挥发性气体。4.回收粉使用比例过大。5.两种不同性质的粉末混杂。6.粉末涂料质量差。

解决办法：1.选择合适的前处理工艺。2.调整适宜的固化条件。3.净化烤炉。4.回收粉过滤后与新粉混合用，以<30%为宜。5.换粉前彻底清理喷粉系统。6.更换质量好的粉末。

The reasons causing: 1.Poor quality of substrate pretreatment. 2. Baking time is too long or temperature is too high. 3. There are volatile gases in the furnace. 4. Excessive use of recycled powder. 5. Two powders of different properties were mixed. 6. Powder coating Quality is poor.

Solutions: 1. Select appropriate pretreatment process. 2. Adjust the appropriate curing conditions. 3. Purify oven. 4. Recycle powder after filtration and mix with new powder, it is advisable to use less than 30%. 5. Thoroughly clean the powder spraying system before changing powder. 6. Replace quality powder.

六、涂膜有气孔、针孔 The film has pores, pinholes

产生原因：1.工件表面有气孔。2.工件表面有处理残留液，脱脂、防锈不彻底。3.导电腻子刮得太厚，未干透。4.喷枪离工件太近，施工电压过高，造成涂层击穿。5.烘道内有挥发气体。6.涂层太厚，或涂膜没有充分固化。7.粉末涂料本身问题解决办法。

解决办法：1.加强工件的加工处理。2.改进前处理工艺。3.延长烘烤时间。4.调整工艺参数。5.清理烘道，净化炉内气体。6.控制涂膜厚度至50-80um，调整固化条件。7.更换合格粉末涂料。

The reasons causing: 1. There are pores on the surface of the workpiece. 2. There is residual solution on the surface of workpiece, degreasing and rust prevention is not complete. 3. The conductive putty is scraped too thick and not completely dry. 4. The spray gun is too close to the workpiece, and the construction voltage is too high, resulting in the breakdown of the coating. 5. There are volatile gases in the baking passage. 6. The coating is too thick, or the film is not fully cured.7. Solution to the problem of powder coating itself.

Solutions: 1. Strengthen the processing of workpiece. 2. Improve the pretreatment process. 3. Extend baking time. 4. Adjust the process parameters. 5. Clean the baking path and purify the gas in the furnace. 6. Control film thickness to 50-80um and adjust curing conditions. 7. Replace qualified powder coating.

七、涂膜机械性能差，涂层整块脱落 Poor mechanical properties of coating, coating the whole off

产生原因：1.基材质量差，前处理方法不当。2.烘烤条件不当，固化不完全或烘烤过度。3.粉末质量差，或已超过保质期。

解决办法：1.改进前处理。2.确定合适的烘烤工艺。3.选用合格粉末，超期的需作全面检查。

The reasons causing: 1. Poor quality of substrate, improper pretreatment.Improper baking conditions, incomplete curing or over baking 3. Poor quality of powder, or beyond the shelf life.

The solution:1. Treatment before improvement.2. Determine appropriate baking process.3. Select qualified powder, and make a comprehensive inspection for overdue powder.

八、涂膜耐腐蚀性差 Poor corrosion resistance of the coating

产生原因：1.涂膜没有充分固化。2.烘烤炉温度不均匀,温差大。3.工件处理不当。4.粉末涂料性能差。

解决办法：1.根据涂料性能调整烘烤条件。2.选择合适的烘炉,上下温差±5℃。3.加强前处理,避免处理液残留在工件表面。4.更换合格粉末涂料。

Causes: 1. The film is not fully cured. 2. Uneven oven temperature and large temperature difference. 3. Improper treatment of workpiece. 4. Poor performance of powder coating.

Solutions: 1. Adjust baking conditions according to coating properties.2. Choose an appropriate oven with temperature difference of ±5℃.3. Strengthen pre-treatment to avoid residual treatment liquid on the workpiece surface.4. Replace qualified powder coating.

九、粉末飞扬 Poor corrosion resistance of the coating

产生原因：1.静电发生器无高压产生或高压不足。2.工件接地不良。3.气压过大。4.回收装置中风道阻塞。5.前处理不彻底（锈、油）。6.粉末涂料本身问题。

解决办法：1.检查静电发生器，调整电压。2.清理挂具，保持接地。3.调整气清理回收装置。5.加强前处理工艺。6.使用合格粉末涂料。

The reasons causing: 1. No high voltage generated by the electrostatic generator or insufficient high voltage. 2. The workpiece is poorly grounded. 3. Air pressure is too high. 4. Air duct in recovery device is blocked. 5. Incomplete pretreatment (rust, oil). 6. Problem of powder coating itself.

Solutions: 1. Check the electrostatic generator and adjust the voltage. 2. Clean the hanger and keep it grounded. 3. Adjust the air cleaning and recovery device. 5. Strengthen the pretreatment process. 6. Use qualified powder coating.

十、供粉量不均匀喷粉量时高时低 the powder supply quantity is not uniform when the powder spraying quantity is high and low

产生原因：1.粉管局部阻塞，粉末流动性差。2.空气压力不足，压力不稳定。3.空气中混有油、水。4.供粉器流化不稳定，供粉器粉末过少。

解决办法：1.清理粉管的杂物或结块，保持粉管畅通，调整粉末涂料干粉流动。2.选择合适的空压机。3.定时排除空压机中的油、水。4.保持流化床气压稳定，并定时添加新粉。

Causes: 1. Partial blockage of powder tube, poor fluidity of powder. 2. Insufficient air pressure and unstable pressure. 3.The air is mixed with oil and water. 4. The powder feeder is unstable in fluidization and has too little powder.

Solution: 1. Clean up the debris or clumps of powder tube, keep the powder tube smooth, adjust the flow of powder coating dry powder. 2. Select the appropriate air compressor. 3. Regularly remove oil and water from the air compressor. 4. Keep the pressure of fluidized bed stable and add new powder regularly.