| With decades of rapid development, our country’s highway network construction has been basically completed, while the vast majority of highway has gradually entered a period of repair and maintenance, which provides enormous developing for the study of Road Maintenance Machine. The cold milling machine is an essential leading facility for road maintenance, but our country is lack of related theory design experience for the milling drum, the most fundamental reason is lack of the study of milling process, therefore it is particularly urgent for the design of milling drum to study the load fluctuation of the milling drum in milling process. The main research content of this thesis is the dynamic simulation of the milling drum in the milling process. Through the study of the load fluctuation of different drums, which can provides guidance for the theoretical design of the drums. We had better to choose milling parameters through studying the influence of milling parameters on the resistance of milling drum.This thesis mainly studies the load fluctuation of the milling drum in the milling process. First of all, we should study the structure parameters of milling drum and their effects on the milling performance, and the design principle of these parameters and the method. Secondly, the law of the kinematics and dynamics are analyzed. Finally, the model of milling drum is designed and established, and the simulation analysis and optimization are carried out.In this dissertation, first of all, we understand the development situation of advanced milling technology and milling simulation at home and abroad. Secondly, the relationship of structure parameters of milling drum and milling cutter are studied through the existing theory and practical experience, thus the different cutters layout’s milling drum are designed to compare the load fluctuation between them. Then the shear failure criterion of asphalt material is applied to study the stress of cutter in the milling process, and the corresponding theoretical formula ate deduced. Finally the model of the designed milling drum are established by the Solidworks, and imported into the dynamics analysis software Adams to simulate the milling process. At first, we analyze the resistance and the resistance moment of single cutter, and on this basis we study the load fluctuation of milling drum with multi-cutters. Thus the structure parameters of milling cutter can be optimized, and we can research the influence of milling parameters on the resistance of milling drum.Some conclusions can be obtained through the above analysis and research. When the milling drum has a single cutter, the resistance and resistance moment of every direction of milling drum is consistent with the law of milling thickness in the milling process. However, the force in vertical direction changes downward from up. The impact of milling drum is mainly come from horizontal. When the multi-cutters act on the milling drum, the resistance and resistance moment of milling drum achieve stable, which present periodical variation. What’s more, the mainly load fluctuation also comes from horizontal. The uniformity of cutter layout on milling drum is very important for the impact of milling drum. When cutters are arranged uneven, its resistance and resistance moment will be reduced, but the load fluctuation obviously increases. When the phase difference between cutters on drum with uniform of cutters layout will be reduced, the resistance and resistance moment will increase, but the range of load fluctuation doesn’t change. The sharp angle and installation angle of cutter are optimized, the optimization of number is 70° and 45°, and the resistance moment dropped 471N·m. When the ratio k of the rotation speed n(r/min) to the horizontal speed v(mm/s) unchanged, the impact strength of the drum also doesn’t change, but the impact frequency will change. When the ratio k increases, its impact strength is inversely proportional to the rotor decreases. |
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