Design And Experiment On Impurity Removal Equipment Of Potato Receiving Hopper

China’s potato planting area and total output rank first in the world.Potatoes are the fourth major food crop in China.They have extremely high nutritional and economic value.They are of great significance to increase economic income,promote potato industrial production,and ensure national food security.The cleaning and impurity removal after potatoes harvest is an important part of potato industry,and it is the basis for promoting industrial loss,value preservation,and appreciation.The impurity removal process mainly involves problems such as high labor intensity,labor consumption,difficulty in removing impurities,and easy damage.The level of comprehensive mechanization of potato in China is relatively low.The cleaning and removal technology and equipment basically rely on imports or the study of foreign machinery.The theoretical research,cleaning and loss prevention are not deep enough.This topic combines the national key research and development topics to study potatoes hopper.Impurity removal technology and equipment,starting from the physical and mechanical properties of potatoes,in-depth exploration of the mechanical and kinematic characteristics of potatoes and the impurity removal roller,analysis of the objective laws of potato removal and impurity removal and damage prevention,and proposed a northern cropping area To remove the clay on potatoes surface,an adjustable spiral roller cleaning equipment was designed.The scope of the main parameters was determined through the analysis of the cleaning time,the number of times and the classification of potato pieces,and related experiments and parameter optimization were completed.It solves the key problems of potato soil removal and impurity removal,reducing damage and loss,provides a new technology for China’s potato storage,impurity removal and marketing,and provides a reference for the theoretical research of potato soil removal and impurity removal.The main content and results are as follows:(1)Determination of potato material characteristicsThe Eugene 885 potato chunks harvested for three days in the northern first cropping area were selected as the research object,and the basic physical and mechanical parameters of the potato chunks were measured.The long axis size of the potato chunks is concentrated in80～100mm,the width is concentrated in 52～69mm,and the height is concentrated in 51～63mm,accounting for 80%～85%.The three-axis average size of potato pieces is:length 84.3mm,width61.6mm,height 55.2mm;the density of potato pieces is 1.2g/cm~3;The friction coefficient of the polyurethane plate is 0.69;the elastic modulus of the potato block is 3.61MPa,and the Poisson’s ratio is 0.43,which provides parameter support for the design of the equipment and simulation analysis.(2)Design of adjustable spiral roller impurity removal equipmentAdopting friction cleaning,hydraulic drive,parallel four-bar support,etc.,an adjustable spiral roller cleaning equipment is designed,and the structure and working principle of the cleaning equipment are explained.Based on the three-axis dimensions of potato chunks,a symmetrical spiral impurity removal roller was designed,with a length of 1.6m,a diameter of 100mm,a spiral blade height of 15mm,and a pitch of 30mm.By analyzing the influence of different numbers of trash rollers on the quality of trash removal,it is determined that the best number of trash rollers is6,and it is designed to be installed in a staggered arrangement.The support frame is designed as a parallel double four-bar connection mechanism with a node spacing of 90mm.The upper end of the support frame is fixed on the frame,and the lower end is installed on a horizontal slide rail.It is pushed by a hydraulic cylinder to realize the clearance of the impurity removal rollers and the inclination of the equipment.Stepless adjustment.(3)Mechanism analysis of impurity removal characteristicsUsing mechanics and kinematics theory,analyze the potato’s tumbling motion,potato soil separation motion and friction force on the impurity removal equipment,and determine that the main factors affecting the impurity removal effect are the distance of the impurity removal roller,the inclination angle of the equipment,and the rotation speed of the impurity removal roller.Through the analysis of the difficulty of the potato chunks overturning movement,the cleaning operation time,the limit position of the equipment and the number of cleaning operations per unit time,combined with the division of the potato chunk grade specifications,the main parameter range is determined to be 105～155mm between the cleaning rollers.,The inclination angle of the equipment is 8°～16°,the speed of the impurity removal roller is 60～120r/min,and the above analysis results are combined to provide theoretical support for subsequent simulation and experimental design.(4)Simulation simulation of potatoes separated from soil separation efficiencyAccording to the measured physical parameters of the potato,the discrete element simulation model of the potato,the soil and the impurity removal equipment is established.The EDEM simulation software is used to simulate the impurity removal operation of the designed impurity removal equipment.The results show that the designed impurity removal equipment can achieve impurity removal.Operational requirements,the theoretical impurity removal rate reached more than 93%,which can meet the needs of potato storage operations,verifying that the designed impurity removal equipment has good impurity removal performance.(5)Bench performance test and parameter optimization of the impurity removal equipmentAccording to the main factors influencing the impurity removal effect determined by the theoretical analysis,the factor level range is divided,and the impurity removal rate and the damage rate are the test evaluation indicators.According to the test method specified by the relevant industry standards,the loading speed is 20t/h.Under the condition that the conveying speed of the conveyor belt is constant at 0.6m/s,the quadratic regression orthogonal rotation combination test is carried out to explore the influence of various factors on the quality of impurity removal,and the parameters of the test results are optimized.The test results show that:When the trash roller spacing is 125mm,the equipment inclination angle is 10°,and the trash roller rotation speed is 112r/min,the operation effect is the best,the potato damage rate is 0.65%,and the impurity removal rate is 96.03%,which can effectively improve the impurity removal quality,which is better.To meet the requirements of potato storage operations.