Design And Test Of Front Mounted Belt Clamping And Conveying Cotton Stalk Pulling Device

Cotton is an important cash crop.As its main by-product,cotton stalk is a high-quality renewable biomass resource.The whole plant selection of cotton stalk can avoid the transmission of diseases and pests and the adverse effects of stubble on tillage and land preparation,and realize the reuse of resources.The existing cotton stalk whole plant pulling machine has the problems of missing pulling rate and high breaking rate.Therefore,according to the agronomic requirements of cotton picking and planting in Xinjiang,a front belt clamping and conveying cotton stalk pulling machine is designed and a prototype is made.The test results show that the machine can realize the whole plant pulling and orderly laying of cotton stalk.The main work and conclusions of this paper are as follows:(1)The physical and mechanical properties of cotton stalk are experimentally studied,which provides a technical reference for the design of the whole machine and key components of the front belt clamping and conveying cotton stalk puller.The diameter,plant height,root length and moisture content of cotton stalk were measured,and the mechanical characteristic parameters such as tensile strength,tensile failure load and transverse compression strength of different parts of cotton stalk were measured.The test results showed that the closer the part to the root of cotton stalk,the higher the tensile strength and transverse compression strength.The study on the pulling resistance of cotton stalk showed that the maximum pulling resistance of cotton stalk in the experimental plot was about 821 N.(2)The whole machine and key components of the front belt clamping and conveying cotton stalk puller are designed and the prototype is made.According to the cotton picking and planting mode of machine,based on the test results of physical and mechanical properties of cotton stalk,the technical requirements of machines and tools are clarified,the design scheme of the whole machine of the front belt clamping and conveying cotton stalk lifter is determined,and its working principle is introduced.The front suspension device,lifting and conveying mechanism and hydraulic system are the key components of cotton stalk puller.The front suspension device is designed and analyzed;According to the planting mode of machine picking cotton in Xinjiang,the structure design and parameter calculation of the lifting and conveying mechanism are carried out,and the force analysis of the process of lifting and conveying the cotton stalk is carried out;The causes of missing pulling and breaking are analyzed to avoid these two situations;The principle of stalk pulling is analyzed,and three factors affecting the operation effect of machines and tools are determined;The hydraulic oil circuit is designed,and the main hydraulic components are selected.(3)In order to test the working performance of machines and tools,the field experiment was designed and carried out by using the orthogonal test method,and the experimental research on relevant parameters and indexes was carried out.Based on the single factor experiment,taking the forward speed of machines and tools,the rotating speed of driving wheel and the stalk pulling height as the influencing factors,and the cotton stalk breaking rate and missing pulling rate as the experimental indexes,a three factor and three-level orthogonal experiment was carried out.Taking the minimum pull-out rate and the minimum missing pull-out rate as the research goal,the test results are analyzed by variance,and the better parameter combination is obtained as follows: forward speed 2 km/h,driving wheel speed 250 r/min and stem pulling height 80 mm.Using the above optimized parameters for verification test,the cotton stalk breaking rate and cotton stalk leakage rate are 7.34% and 9.81% respectively,which basically meet the requirements of stalk pulling operation,and verify the rationality of the overall design of the machine.