Research On The Key Components On Small Movable Branch Grinder

The reality about the shortage of conventional energy is gradually emerging on the stage of world development, fog haze pollution and other environmental issues have been a threat to our health life, and global warming has become one of the key issues of global concern. In this context, the choice of development and use of clean and renewable energy will become an inevitable development; biomass is one of the key development targets of the renewable energy sources. However, most of the forestry materials need to be crushed on the early stage in order to be further processed and exploitation, so, crushing technology and equipment have a decisive role in the process about the transformation and utilization of forestry materials. Therefore, for the problems, such as that mountain woods and orchards annually produce large trimmed branches and waste branches cannot be effectively cleaned up the and used, which urgent need to be crushing on-site and transported out for timely in order to use them convenient, and that the reasons which mountainous terrain and realities, limits the effective use of existing equipment into the mountains, we designed and developed a small moveable branch grinder. According to the setting of design goals and technical route, as well as the researches on the characteristics of the wood materials and shearing tests of related branches, we have researched, selected and determined the overall design scheme, completed the detailed design and calculation of the key components, established three-dimensional models, and fished finite element analysis of the hammer and spindle and virtual prototyping dynamic balancing analysis for the rotor assembly. What’s more, we successfully processed and assembled a test prototype, and did the relevant crushing testes to determine the relevant parameters about the grinder and to verify the crushing effect.The main contents and conclusions are as follows:1) This grinder crushing objects are wood-based materials. Thus, on the basis of the existing wood-based materials research theory, we study and analysis the composition of wood material, the influence of related components of wood materials to their properties, and the mechanical properties and the impact of factors to the mechanical properties of wood materials. In addition, we have done the mechanical shearing tests of Luan trees branches and citrus branches, compared the shear strength of two different branches in different moisture conditions. After analysis of the shearing tests, we have known the trend about the shear strength of branches, and provided a theoretical basis and practical basis to the design and calculation of the grinder.2) Through the study of crush theory, combined with the design goals for the subject’s branch grinder which can crush a maximum diameter of30mm fruit tree branches, get the crush size up to5mm or less, have good adaptability of materials, and be suitable for mountain orchards and others, we have researched and identified the overall design grinder machine in the subject. It is that, by using single-channel feed roller feeding port feed branches uniformly continuously, then, branches were cut,hit and crushed by hammers directly in the crushing chamber, no pre-processing such as cutting by cutters, after one time crushed and cut, the branches changed into the sawdust and run out, without the cycle repeated crushing process. And thereby, we determined the specific design of the various parts.3) Combined with the overall design, we have studied and identified the detailed design of the key parts, such as the rotor assembly, the feeding device, grinding chamber, and so on. With the study design and detailed calculations about hammer and other key components of the branch grinder, we determine the parameters and dimensions of those parts, and assembled the whole machine. We completed the detailed and complete design of the small moveable thick hammers branch grinder, which feeding branches by the feeding roll through the single-channel, and crushing branches in a non-repetitive way.4) With the use of the Pro/E software, have finished building the3D modeling of the key components, virtual assembly of the machine, and animation simulation and volume interference analysis of the key elements to ensure the rationality of the design. With the use of the ANSYS Workbench software. have finished the hammer’s statics finite element analysis demonstrated the strength of its design to meet the work requirements, as well as the rotor spindle’s modal analysis to ensure that the design of the spindle does not occur resonance phenomenon in the grinder during operation; With the use of the ADAMS software,have finished the rotor assembly’s balancing analysis to prove the design of the rotor assembly of the grinder running smoothly at high speed when in balancing state.5) Successfully built the test prototype platform to meet the test conditions, and finished the crushing experiments. The crushing experiments for determining the spindle speed showed that the optimum spindle speed range for the grinder is2050r/min2200r/min, and the crush confirmatory experiments show that when the spindle speed is2100r/min,the productivity can reach0.851m3/h, and the unit energy consumption can be as low as3.162kwh/m3. It has obvious advantages compose to the similar class small wooden grinders.