Fiber Selection and Pretreatment
The production of PPS dust filter bags begins with the selection of high-quality PPS fibers. These fibers usually need to be pretreated before use to remove impurities and adjust the surface properties of the fibers, ensuring better bonding during subsequent processing and improving the overall performance of the filter bags. Pretreatment methods include washing, drying, surface modification, etc.
Needle Felting
The pretreated PPS fibers are carded into a web and then needled by a needling machine. During the needling process, barbed needles repeatedly penetrate the fiber web, causing the fibers to entangle with each other, forming a needle felt with a certain thickness and strength. The needling process enables the fibers to interweave in three-dimensional space, increasing the dirt-holding capacity of the filter bags and improving the filtration accuracy. By controlling the needling density and depth, the structure and performance of the needle felt can be adjusted to meet the requirements of different working conditions.
Surface Treatment
To further enhance the performance of PPS dust filter bags, the needle felt is usually subjected to surface treatment. Common surface treatment methods include singeing, calendering, and film coating. Singeing treatment can remove the fluff on the surface of the filter bags, reducing dust adhesion and making dust removal easier. Calendering treatment rolls the surface of the filter bags under high temperature and pressure, making the surface smoother and improving dust release. Film coating involves covering the surface of the filter bags with a Polytetrafluoroethylene (PTFE) film. This film has a microporous structure, which can further improve the filtration accuracy, achieving efficient filtration of ultra-fine dust particles. Meanwhile, it can also enhance the water and oil resistance of the filter bags.
