Performance Analysis And Surface Optimization Of High Pressure Grinding Rolls Based On Discrete Element Method

High-pressure grinding rolls is an important mineral powder grinding equipment mainly used for grinding and crushing various materials such as ores,cement,coal,etc.High-pressure grinding rolls has the advantages of high efficiency,energy saving,and environmental protection.It can greatly improve the efficiency and quality of powder processing,while reducing dust pollution,which meets the requirements of environmental protection.However,there are some defects in the operation process of high-pressure grinding rolls.The roller surface wear is more serious,and the roller surface wear is unevenly distributed,which greatly shortens the service life of the rollers and affects the performance of the high-pressure grinding rolls.Therefore,performance analysis and roller surface structure optimization of highpressure grinding rolls are necessary.This paper combines with the Shanxi Coal-based Key Science and Technology Tackling Project to conduct research on the performance analysis and roller surface optimization of high-pressure grinding rolls based on the discrete element method.The research contents are as follows:Ⅰ.Summarize the current research and development status of high-pressure grinding rolls both domestically and abroad.Based on relevant research data on the modeling of highpressure grinding rolls,introduce the structure and working principle of high-pressure grinding rolls.On this basis,analyze and solve the main structural parameters of high-pressure grinding rolls,establish the main performance prediction model of high-pressure grinding rolls,and analyze the existing edge effects.Ⅱ.Based on the compression-expansion characteristics of the material and the motion characteristics of the rolls,the working range of the high-pressure grinding rolls is divided into three zones: acceleration zone,compression zone,and expansion zone.Based on this,the movement of materials and the distribution of forces on the rolls in each zone are analyzed and modeled.In order to predict the pressure distribution of the rolls more accurately,a piston pressure test is adopted to simulate the compression-expansion characteristics of the material.Through this test,the force-displacement curve of the material during compression and crushing can be obtained,and the pressure distribution on the surface of the rolls can be predicted based on the relative density of the material in the working range.Ⅲ.Based on the structural dimensions and working principle of the high-pressure roller mill,a discrete element simulation model of the high-pressure roller mill is established for simulating the actual operating condition and material comminution process of the highpressure roller mill by combining the latest research progress of the high-pressure roller mill.In addition,data collection is carried out for the actual operating high-pressure roller mill,and by comparing the simulation results of the high-pressure roller mill with the test results,the results show that the simulation model has certain feasibility.On this basis,the size and arrangement arrangement of the roll surface structure of the high-pressure roller mill are optimized by the discrete unit method,and the multi-objective optimization is carried out with the roller nail size,spacing ratio and spacing angle as the research objects,and the productivity,power consumption and discharge size as the optimization objectives.In summary,this article has established the main performance calculation model of the high-pressure grinding rolls and analyzed the material crushing process.The performance of the high-pressure grinding rolls was simulated by the discrete element method,and the roller surface structure of the high-pressure grinding rolls was optimized and designed accordingly.The research work in this article has a certain reference value for the design of high-pressure grinding rolls.