One of the challenges in the powder coating process is powder spitting. It causes irregular powder output onto the substrate and leads to small film thickness fluctuations.
Understanding its causes and implementing solutions is crucial for maintaining quality standards.
- Operational settings: An optimal balance between the air velocity and powder output is necessary for consistent results.
- Equipment: Mechanical damage, wear, or contamination of the equipment impacts the performance of the powder coating lines.
- Tubes: An optimal tube layout is of the utmost importance: the shorter the circuit, the less chance of obtaining defects. The tube material also influences the air velocity and powder output. The Protech Groups advises following the recommendations of your powder coating line manufacturer.
- Air pressure fluctuations: Fluctuations in air pressure disrupt the balance required for smooth powder application.
- Particle size distribution: Excessive fine powder forms agglomerations which might result in an uneven coating.
- Powder wetness: A relative humidity (RH) between 40% and 60% is optimal for the powder coating process. A higher or lower RH can cause various problems, such as powder spitting.
- Control: Continuously monitor and adjust the air velocity and pressure to ensure optimal flow.
- Maintenance: Cleaning the powder spraying installation regularly and thoroughly is vital.
- Particle size distribution of fresh powder: Fine-tune the particle size distribution for optimized powder flow.
- Balanced powder input: A good balance between fresh and recovered powder minimizes application difficulties, including powder spitting.
While powder spitting may pose a difficulty in the powder coating lines, adopting the right strategies will help conquer them. You can uphold the highest standards of quality and precision in your powder coatings lines by addressing the underlying causes. Our experts are here for you and will help you identify those culprits and find the right solutions. Contact us for more information: https://www.theprotechgroup.com/contact/
