Structural Analysis of String-Wound Filter Cartridges

As a commonly used depth filter element, the structural design of string-wound filter cartridges directly determines their filtration precision, contamination holding capacity and service life. The core of the filter cartridge adopts a composite structure of "skeleton + winding thread", supplemented by end cap sealing components, forming a filtration system with distinct layers and synergistic functions. It is widely used in water treatment, chemical industry, food and beverage and other fields.

The skeleton serves as the supporting foundation of the yarn filter cartridge. It is usually made into a tubular structure using corrosion-resistant and high-strength materials such as polypropylene, polyethylene or stainless steel. A large number of through-holes are evenly distributed on the tube body, which on the one hand provide a smooth channel for the filtered fluid, and on the other hand support the outer winding thread to prevent the filter element

 from deforming or collapsing due to pressure changes during the filtration process. The pore size of the skeleton needs to be matched with the thickness of the winding thread and the filtration precision, so as to ensure that it neither hinders fluid circulation nor effectively bears the winding layer.

The winding thread is the core component to achieve the filtration function. It is made of fiber materials with excellent filtration performance, such as polypropylene, polyester and glass fiber. Through the precision spiral winding process, the fiber thread is evenly wound on the surface of the skeleton. During the winding process, the filtration precision of the cartridge filter (usually ranging from 1 to 100 μm) can be precisely controlled by adjusting the winding density and thread diameter. High-density winding areas can trap fine impurities, while low-density areas are used to increase contamination holding space, forming a "depth gradient filtration" structure, which improves the contamination holding capacity and service life of the filter cartridge.

The end caps and sealing components are the key to ensuring filtration tightness. The end caps are made of materials matching the skeleton and fixed at both ends of the element filter through hot-melt welding or bonding processes to prevent fluid from leaking from the edge of the filter cartridge. Some high-end filter cartridges are also equipped with sealing rings at the end caps to further enhance the sealing performance, avoid mixing of unfiltered stock solution and filtered clear liquid, and ensure the filtration effect.

Overall, the structural design of string-wound filter cartridges integrates supporting stability, filtration accuracy and sealing reliability. Through the synergistic effect of various components, it achieves efficient depth filtration and meets the purification needs of different industries.