摘要
为解决黄淮海地区玉米直接进行籽粒收获破碎率和未脱净率高的问题,该文在分析现有脱粒滚筒结构特点的基础上,设计了组合式轴流玉米脱粒滚筒,选取滚筒转速、滚筒倾角和凹板间隙为试验因素,在自制的玉米脱粒试验台上进行了单因素试验和正交试验,并运用SAS统计分析软件对试验结果进行了分析。单因素试验结果表明:随着滚筒转速的增大,籽粒破碎率先降低后升高,未脱净率则急剧减小并趋于稳定;随着滚筒倾角的增大,籽粒破碎率和未脱净率则逐渐变小;随着凹板间隙的增大,籽粒破碎率先降低后升高,未脱净率先升高后降低并趋于稳定。正交试验结果表明:影响籽粒破碎率和未脱净率的主次因素顺序均为滚筒转速、滚筒倾角、凹板间隙,且转速430 r/min、滚筒倾角6?和凹板间隙55 mm时籽粒破碎率和未脱净率均最低。该研究可为高含水率玉米脱粒滚筒的设计提供参考。
Ear picking and grain harvesting are the2kinds of corn mechanized harvesting.Grain harvesting can complete harvesting,threshing and cleaning process at one time,which reduces operation process and improves working efficiency.It is the development trend of China corn harvest.The planting pattern in Huang-Huai-Hai region is wheat-corn rotation.The grain moisture content of corn is about30%-35%when harvesting.This causes high breaking rate and un-threshing rate and restricts the development of corn grain harvest.There were many current studies on corn threshing process at home and abroad.But most studies were on small corn threshing machine.This article analyzed the factors affecting breaking rate and un-threshing rate,which provided a theoretical basis for research of large corn grain harvest machine.Based on analysis of the structure characteristics of the existing threshing cylinder,this article designed the combined axial flow corn threshing cylinder.Based on analysis of threshing process characteristics,radial feed and radial exhaust style cylinder was selected.According to calculation,the threshing cylinder designed had a diameter of650mm and a length of2800mm.The cylinder chose rasp bars and nail teeth as threshing elements.In order to make the material in the cylinder have a backward transmission capacity,the rasp bars and nail teeth were arranged in4heads withthe pitch of4800mm.The test bed adopted grid and punched combined concave.Two spiral guide bars were arranged at the end of the inner wall of the cover to control the speed of material movement.The spiral angle of the guide bar was35°,and the diameter was8mm.In October2016,using the threshing test bed,the threshing experiment was completed at the experiment base of Shandong Academy of Agricultural Machinery Sciences(SAAMS)in Zhangqiu District,Jinan City,ShandongProvince.Experiment subject was summer corn in mature period in Shandong with the moisture content of32%-34%.The experiment was carried out according to GB/T21961-2008Test method for maize combine harvester and GB/T21962-2008Technical requirements for maize combine harvester.The cylinder speed,cylinder angle and concave clearance were chosen as experiment factors,and the breaking rate and un-threshing rate as main test indices.In each experiment,150corn ears were fed,and the experiment of each group was repeated3times.In order to determine reasonable range of each factor,single factor experiments of the3factors were firstly carried out.The single factor experiments showed that with the increase of cylinder speed,the lowest breaking rate was5.52%when cylinder speed was450~500r/min;the un-threshing rate decreased and the lowest un-threshing rate was0.2%when the cylinder speedexceeded350r/min.The breaking rate decreased while the un-breaking rate increased with the increase of concave tolerance and the lowest breaking rate was3.35%,the lowest un-threshing rate was0.12%.The breaking rate and un-threshing rate were both decreased with the increase of cylinder angle and the lowest breaking rate was2.88%,the lowest un-threshing rate was0.06%.On the basis of single factor experiment,this article chose cylinder speed,cylinder angle and concave clearanceas investigation factors and carried out orthogonal experiment with3levels of each factor.By using SAS(statistical analysis system)software and Duncan’s method,main sequence and significance level of the factors were tested,and the optimal parameter combination was found out.The orthogonal experiment showed that the sequence of the factors affecting breaking rate and un-threshing rate was cylinder speed,cylinder angle and concave clearance.The factor combination obtaining the lowest breaking rate and un-threshing rate was cylinder speed of430r/min,cylinder angle of6°and concave clearanceof55mm.With this factor combination,the breaking rate was2.96%and the un-threshing rate was0.19%.
作者
邸志峰
崔中凯
张华
周进
张明源
卜令昕
Di Zhifeng;Cui Zhongkai;Zhang Hua;Zhou Jin;Zhang Mingyuan;Bu Lingxin(Shandong Academy of Agricultural Machinery Science, Jinan 250100, China;Lovol Heavy industry co.ltd., Weifang 261206, China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2018年第1期28-34,共7页
Transactions of the Chinese Society of Agricultural Engineering
基金
山东省2016年重点研发计划项目(2016GNC112002)
山东省农业科学院农业科技创新工程"主要农作物农机装备研制"项目(CXGC2016B08)
山东省农机装备研发创新项目(2016YF031)
关键词
农业机械
玉米
脱粒
轴流滚筒
正交试验
agricultural machinery
corn
threshing
axial flow cylinder
orthogonal experiment
作者简介
邸志峰,工程师,主要从事农业机械设计研究。Email:dzf_1125@163.com。;通信作者:崔中凯,工程师,主要从事现代农业装备技术研究。Email:kevin6119@qq.com。
