Research On Vibration Control Of Horizontal Decanter Centrifuge With High-speed

With the increasing requirements of material separation in industry, horizontal decanter centrifuges are developing towards larger slenderness-ratio and higher speed. Dynamic characteristics of centrifuge will change a lot because of the increasing of its slenderness-ratio, and higher speed will add much more force, both of which will intensify vibration. So, controlling vibration is critical to guarantee the centrifuges with large slenderness-ratio and high speed operating safety. Based on the Fundamental "Research funds for the Central Universities"(2013QNA4033), the Program "Zhejiang province science and technology innovation team"(2011R50005), and the Project "Research on vibration reduction technology of LW520E Ⅱ decanter centrifuge", in this paper, lots of research have been done on vibration control of decanter centrifuge through Optimizing the dynamic structure, and madding dynamic balance with water-load, the following results have been achieved:1. Detailed measures are given to optimize dynamic characteristics of horizontal decanter centrifuge with high-speed.The critical speeds and modes of vibration have been achieved by establishing its dual-rotors system. The natural frequencies and modes of vibration of centrifuge have been achieved by establishing its rotor-bearing-foundation system. The way of reducing the mass and the length of cantilever segment of the differential mechanism has been proposed to increase the first critical speed. In order to increase the second critical speed, we can enhance stiffness of the main bearing in the small end and bending stiffness of inner spiral. Through increasing the height and width of centrifuge’s two main beams, and strengthening the linkages between them, the natural frequencies can be increased. Then, the dynamic characteristics of the horizontal decanter centrifuge have been tested, and the result demonstrated that optimization works effectively and the model meets the demands of engineering. All the work will play an important role in the design and development of horizontal decanter centrifuge.2. The mechanism of vibration increasing by water has been investigated.CFD models of horizontal decanter centrifuges with water-load were built, and many conclusions have been achieved by calculating the modes in Fluent and analyzing in theory. It is the spatial dissymmetry created by manufacturing inner spiral that makes unbalance lateral force on the spiral by water, then, vibration increased.3. The method of dynamic balance of the horizontal decanter centrifuge with water has been proposed.Based on the mechanism of vibration increasing by water, the method to balance the rotor by reducing the centrifuge force of water in some parts has been developed, which was successfully used on balancing horizontal decanter centrifuge with water. Vibration decreased significantly after dynamic balancing, which showed the method was feasible, and the aim of controlling the vibration of centrifuge has been achieved.