The Structure Optimization And Experiment Of Molding Die Of Plunger-Type Roller Ring Die Molding Machine

Biomass energy has broad development prospects due to its clean,low-carbon,and renewable characteristics.As a large agricultural country,China has certain foundations and advantages in the development of biomass energy.There are many directions for the development and utilization of biomass energy.Currently,biomass molding technology has become one of the main development directions.Therefore,this paper has perfected the design method of the molding die of the plunger-type roller ring die molding machine,and further explored the biomass molding mechanism,which will provide a certain reference for future research on biomass molding technology.In this paper,based on the analysis of the movement of the molding die of the plunger-type roller ring die molding machine,a mathematical model of the trajectory curve of the apex of the roller relative to the ring die molding hole is obtained,which lays a foundation for exploring the theoretical design method of the ring die molding hole.According to the mathematical model,the theoretical design method of the minimum size of the ring die molding hole is established,and the relationship between the cone angle of molding hole entrance?,the entrance radius r_k,the entrance depth H of the molding hole and the plunger length h is determined.Using Matlab for curve fitting,a series of curve fitting formulas with the plunger length as the independent variable and the above-mentioned molded hole structure size as the dependent variable are obtained,and the relative correctness of the theoretical design method is proved by the interference verification diagram.In order to further improve the theoretical design method of the molding hole structure size,the molding process of the plunger-type roller ring die molding machine was simulated by discrete element using EDEM.The rationality of the discrete element simulation model was tested by comparing the discrete element simulation results with the room temperature biomass molding experiment results.Then,according to the discrete element simulation model,the influence of the cone angle of molding hole entrance on the molding process is explored,and it is concluded that the cone angle of molding hole entrance should be educed as much as possible under the premise of no interference in the molding die.In order to explore the influence of different factors on the molding quality,a three-factor five-level orthogonal experiment was designed and implemented.The experiment used caragana korshinskii powder as the raw material,took the moisture content of the raw material,the aspect ratio of the molding sleeve and the granularity of the raw material as the experimental factors,and took the relaxation density,shatter resistance,impermeability and the number of squeezes to achieve stable molding as the evaluation indicators.Through the range analysis and response surface analysis of the experimental results,the order of the influence of the experimental factors on the evaluation indicators was obtained,the regression equation between the experimental factors and the evaluation indicators was established,and the interaction between the experimental factors was analyzed.A single factor experiment was carried out with the moisture content of the raw material,the aspect ratio of the molding sleeve and the granularity of the raw material as variables,and the microstructure of the briquettes was observed with a stereo microscope.The observation results showed that when the moisture content of the raw material and the aspect ratio of the molding sleeve are appropriate,and the granularity of the material is small,the quality of the briquettes is higher.At this time,the materials of the briquettes are mostly in a broken and fitted state.In addition,the microscopic bonding state of the briquette has an certain impact on its relaxation density,shatter resistance and impermeability.The actual production application of the analysis results of the orthogonal experiment was carried out by using the plunger-type roller ring die molding machine.The reasons for the deviation between the actual application results and the orthogonal experiment results were analyzed,and the optimal molding parameter combination was finally determined as:moisture content 11%,aspect ratio 5.25,granularity80%,which will provide a certain reference for the future molding process of caragana korshinskii powder at room temperature.