Research On Optimal Design And Dynamic Characteristics Of Pressurizing And Rotating Unit Of Rotary Drill Rig

Rotary drill rig is one of the important equipments of ore mining operation. Its working efficiency directly determines the subsequent working procedures of mining. With the development of production technology and the increasing demand of mining companies for rotary drill rig, the overseas manufacturers have improved the pressurizing and rotating unit, and abolished the traditional closed chain structure. However the traditional closed chain structure is still adopted in our country, which couldn’t satisfy the mining companies’ demands. This paper combining the project request and the main content is follows.1. The chapter one introduced the developing processes of rotary drill rig and the different types from main manufacturers at home and abroad. The second chapter analyzed and classified the different pressurizing and rotating units. Referencing the overseas advanced unit of pressurizing and rotating, this paper adopted the chainless pressurizing and rotating unit and came up with detailed parameters. Calculated the pressurizing reduction gear ratio and the rotating reduction gear ratio and chose appropriate hydraulic pump and hydraulic motor.2. The third chapter designed the pressurizing gearbox and rotating gearbox by conventional method. In order to decrease the times of operation, improve the computational efficiency and reduce the quality of gear reducer, respectively optimized the pressurizing gearbox and rotating gearbox respectively by the genetic algorithm, and the smaller model’s parameters are derived. Compared results of the genetic algorithm with the results of conventional method, the volume of pressurizing gear reducer based on the genetic algorithm was 20.35% less than the volume based on conventional method; the volume of rotating gear reducer based on the genetic algorithm is 8.64% less than the volume based on conventional method.3. The forth chapter created the three-dimensional model of pressurizing and rotating unit by UG, and imported it to ADAMS in the format of parasolid. Set up reasonable constraints and parameters and established the virtual prototype model in the ADAMS. Simulated the working conditions of drilling and promotion and gained speed and meshing force of each gear. Then compared the simulate dates with theoretic dates, found that the numerical values were almost unanimous, which could prove the correctness and accuracy of the virtual prototype model.4. Due to the importance of pressurizing and rotating unit, the structural strength and stiffness should be ensured. Gained the force of each bearing from the post-processing of the virtual prototype simulation in the different working conditions, then imposed the forces to the corresponding bearing seats. Through the statics analysis, requirements for the rigidity and strength was met. Calculated all the meshing frequencies of gear-driven. Modal analysis was carried out to the pressurizing reduction case, rotating reduction case and all the gears. The inherent frequency of pressurizing reducer was closed to the meshing frequency in the third working condition. Then improved the pressurizing reduction case and avoided the resonance phenomenon.