Design And Experimental Study Of Key Equipment Of Economic Forest Automatic Seedling Breeding Production Line

Nowadays,the role of economic forest seedling cultivation in forestry production is becoming increasingly important.In our province,major economic tree species for afforestation,such as walnut,hazelnut,and Phoebe nanmu,have only partially mechanized the seedling cultivation stage,resulting in high production costs and low seedling output rates.The existing seedling machinery is not targeted and cannot solve the above problems well.Therefore,an economic forest automated seedling production line that complies with the technical regulations for forestry seedling cultivation is urgently needed to replace manual labor,improve mechanization and automation levels.Therefore,this thesis developed an economic forest automated seedling production line to address the above issues.The main research content and conclusions are as follows:(1)Based on the on-site investigation,a nursery production line was designed.Through the on-site investigation of forestry bases,the seedling cultivation mode of major economic forest trees in Zhejiang Province,such as walnut and cashew,was understood,and the functional requirements of the nursery production line were determined.A design plan was proposed that requires the design of supporting equipment such as non-woven seedling bowl forming machine,fixed-point watering machine,holepressing seeding machine,and soil covering machine.It is expected that the operating efficiency of the entire nursery production line should reach at least 1000 plants per hour.(2)Structural design of a nursery production line based on virtual prototype technology.Based on different functional modules and analysis of working principles and key structural dimensions,the structural design of supporting equipment such as the seedling bowl forming machine,point watering machine,hole punching and sowing machine,and soil covering machine is completed.The assembled nursery production line is capable of functions such as non-woven bowl making,filling of seedling container matrix,non-woven cutting,point watering,hole punching and sowing,and soil covering.(3)Based on Simulation,feasibility study and Simulation analysis.Static analysis of the critical structures of the virtual prototype is conducted using Simulation.The maximum concentrated stress and maximum deformation are chosen as evaluation indicators to analyze the feasibility of the overall design scheme.The maximum concentrated stress of the analyzed object is less than the allowable stress,and the maximum deformation of the structure can be ignored.Therefore,it can be concluded that the strength and stability of the whole machine structure meet the requirements and the overall design scheme is feasible.(4)Manufacturing and testing of the seedling production line.The test results show that the entire machine works well and each module can achieve the expected functions.By calculating the seeding efficiency,it is found that when the conveyor belt speed is set to 50mm/s,the production efficiency is about 2844 plants/hour,exceeding the expected target.If calculated for 8 hours a day,it can sow 22750plants;whereas manual work can only sow less than 500 plants a day.Therefore,the overall efficiency of the machine is at least 700%～800% higher than manual work,indicating that the seedling production line meets the requirements and greatly improves the mechanization level and production efficiency of the economic forest seedling cultivation stage,reducing labor costs.It has good practical significance for solving the development problems of the economic forest seedling cultivation industry.