Dry powder coatings are extremely popular due to their many benefits over conventional liquid coatings. They are highly durable, more environmentally friendly, and efficient.
Powder coatings are manufactured by first mixing raw materials such as resins, pigments, additives, and fillers into a homogeneous mixture. This is extruded to form small pellets or chips that are ground into a fine powder. This fine powder needs to be sieved to remove any lumps or impurities. It is extremely important during this stage to remove any oversize particles from the mixture because particles that are too large or too small will result in an uneven coverage and low adherence during dry coating applications.
Overspray (excess paint that blows beyond the area being sprayed) can also be collected and recycled, to reduce waste and material costs, meaning the requirement to sieve is not only exclusive to the pre-application stage.
Farleygreene’s Sievmaster Slimline range of sieving machines provide a highly efficient solution to customers requiring screening of dry powder coatings particularly for removing oversize product. Slimline sieves can be gravity fed as part of a continuous production line or stand alone on mobile frames, they are available in a wide range of screen diameters from 550mm to 1550mm, depending on your desired throughput target.
The Slimline range is also available as a Vacusiev model to support vacuum-pressure transfer systems, providing a fully enclosed system and preventing paint powder leakage.
For powder coating applications, we would recommend that your sieve is installed with our Sievmaster Ultrasonic System, used for very fine powder applications. The ultrasonic screen prevents blockage and blinding and helps to ensure a consistent throughput rate resulting in faster, more effective screening.
For applications requiring multiple separations of different sized particles, we would recommend our Sievmaster Multiscreen range available in three different diameters 800mm, 1200mm, and 1500mm. This grading sieve provides separation of material in up to four grades and is also available with the Sievmaster Ultrasonic System. This machine can precisely output powder in the desired particle size range, with the product that is too large and too small separated.
For customers looking for a highly efficient solution with a smaller footprint and fully mobile design, our Sievmaster 700-ST may be an appropriate solution. The SM 700-ST is also available with a range of different options such as the Sievmaster Ultrasonic System and a vacuum transfer Hopper Loader. This machine has been historically used for this application.
It is vital that clean down of machinery is straightforward in between batch changes of paint powders. Farleygreene sieves have been designed to be taken apart without tools and with minimal crevices, making them easy to disassemble and clean when sieving batches of different coloured paint powder.
Overall, Sieving is a critical step in the powder coating process to ensure that coating is high-quality and consistent. Sieving is essential for keeping the powder particles uniform in size to enhance efficiency and reduce defects.
Contact us today to find out how our sieving solutions can support your manufacture of dry powder coatings.