DESIGN, STRUCTURAL ANALYSIS, AND FABRICATION OF A CONTINUOUS HELICAL KNIFE ASSEMBLY FOR A WATER HYACINTH SHREDDING MACHINE

To overcome the dynamic limitations of conventional cutting mechanisms when dealing with the complex mechanical properties of water hyacinths, this study proposes the design and fabrication of a continuous helical knife drum assembly. This configuration aims to minimize impact loads, achieve a uniform distribution of cutting forces, and enhance overall system stability. The technical parameters were calculated to establish a theoretical basis for developing the helical blade profile from flat steel stock for manufacturing purposes. The system was subsequently assembled and subjected to preliminary experiments both in a controlled testing tank and under actual operating conditions on the VamCo Tay River, Tay Ninh province. Experimental results demonstrated that the system operated with high stability and efficiency, significantly reduced vibrations, and effectively prevented overloading. Operating at a rotational speed range of 300÷350 rpm with a working width of 2,6 m, the equipment successfully fulfilled the requirements for shredding high-density water hyacinth mats (25 kg/m²), producing an output biomass size of <10 cm. This study provides a crucial foundation for refining the design and standardizing the technical parameters for application across various water hyacinth shredding machine configurations.