Design And Optimization Of Key Devices For Continuous Operation Of Wheat Straw Round Bales

China is a large country with large straw production.Straw off-field utilization is one of the methods for the reasonable and effective utilization of straw resources.Mechanized straw storage is the basis for comprehensive utilization of crop straw.At the moment,domestic straw collection machines mainly include straw balers,straw pick-up trucks and so on.The round baler has no knotter,its structure is simple.However,most round baler in China are intermittent operation now.Straw needs to be stopped to wrap the net（rope）and remove the bale after it is formed,which affects the efficiency of the round baler.In this paper,wheat straw is used as the object to design and test the key technologies and devices for continuous round-bundling continuous operations.In this research,Using the 3D software and simulation software,combined with response surface optimization test and orthogonal test,Theoretical analysis,structural design,simulation optimization and parameter optimization of the multi-functional temporary storage warehouse and other key components,and finally the function of continuous operation of the round baler and the improvement of baling efficiency.The main work of this topic and the main conclusions reached are as follows:（1）By using the universal testing machine to test the compression and bending characteristics of wheat straw,the mechanical characteristics and related curves of wheat straw with different moisture content at different loading speeds are obtained,and the corresponding relationship model is established to obtain the factors that affect the straw baling process.（2）Through calculation,the structural scheme of the key device for continuous operation of round bale is determined and a 3D model is established.The key parameters are initially designed and calculated.The modal characteristics of the key device frame for continuous operation of round bale are analyzed by using ANSYS WORKBENCH,And finally verified the stability of the structure.（3）Based on the working principle of the key device for continuous operation of round baling,Analyze it for kinematics and mechanics,and the movement process of straw in the multifunctional temporary storage warehouse is simulated by EDEM.and use the Box-Behnken combined test design method,Analyze the influence of three factors which include the angle between the belt and the horizontal plane,the vertical and horizontal relative distance between the straw conveying mechanism output port and the multi-purpose temporary storage bin on the average pressure peak between the straw particles and the time that the straw particles filled the molding chamber,and a regression optimization model was established.The optimization results showed that when the vertical relative distance between the straw transport mechanism and the multi-purpose temporary storage bin X₁=92 mm,horizontal relative distance X₂=150 mm,the angle between the lower belt and the horizontal plane X₃=30.95°.At this time,the average peak pressure between the particles Y₁=23.0625 N,and the time for the straw particles to fill the forming chamber Y₂=28.028 s,which meet the constraints of the maximum density of straw particles and the shortest baling time.（4）Taking wheat straw as the test object,through field tests,using an orthogonal design scheme,setting the straw moisture content,machine forward speed,and Speed of belt active roller under multifunctional temporary storage as the test factors,using the baling efficiency as the evaluation index,and finally finding the optimal working parameters of continuous operation round baler,it is found that the straw moisture content is 10.7%,the advance speed of the implement is 4 km/h,and Speed of belt active roller under multifunctional temporary storage is 510 r/min,The time required to form a single bale is the shortest.In addition,in the same place,comparing the two modes of continuous operation and discontinuous operation,it was found that the efficiency of continuous operation is higher than that of discontinuous operation by about 22%.Through field tests,the performance of continuous operation round baler is verified,and the reliability is better.