田间作业条件下摘锭耐磨性能及棉花采净率的试验研究

Experimental study on the wear resistance of spindle and cotton totalharvest rate under field conditions

为了探究田间作业条件下摘锭的耐磨性能与棉花采净率,该研究将未钝化摘锭和钝化摘锭安装到采棉机不同采摘头上,在作业面积达到0、150、300、450、600hm^(2)时,获取2种摘锭样本并进行切割制样,分析钩齿磨损形貌,提取钩齿磨损面积及镀层厚度,同时测定2种摘锭的采净率。结果表明:未钝化摘锭的钩齿前齿尖易折断,钝化摘锭的钩齿镀层剥落晚于未钝化摘锭。在相同作业面积下,钝化摘锭的钩齿磨损面积更小,在测试位置的镀层厚度更高;当作业面积达到600 hm^(2)时,未钝化摘锭的钩齿平均磨损面积达到2.9×10^(5)μm^(2),约为钝化摘锭的2.6倍;未钝化摘锭1号、2号钩齿及钝化摘锭1号钩齿测试位置镀层剥落,钝化摘锭具有更加优异的耐磨性能。对照2种全新摘锭的采净率,钝化摘锭的采净率比未钝化摘锭低0.2个百分点;当作业面积达到约200 hm^(2)时,2种摘锭的采净率相差不大;当作业面积超过200hm^(2)时,钝化摘锭的采净率大于未钝化摘锭;当作业面积为450hm^(2)时,未钝化摘锭和钝化摘锭采净率均达到最大值,分别约为96.4%和96.7%;当作业面积为600 hm^(2)时,钝化摘锭的采净比未钝化摘锭高0.5个百分点,钝化摘锭具有更加优异的采摘性能。该研究成果对于采棉机摘锭钩齿的结构优化与修形具有重要意义。

Cotton is one of the most important economic crops and strategic materials in national defense,medicine,and industry.Mechanized harvesting of cotton has been an effective way to promote the development of the cotton industry in China.Among them,a large cotton harvesting equipment,a cotton picker has been widely used in Xinjiang in western China,due to the fast,convenient,and low labor intensity.The spindle is the commonly-used core component in the cotton picker.The product quality and wear resistance of the spindle can determine the operation efficiency,quality,and economy of the cotton picker.The wear failure of the spindle is mainly manifested in the serious wear to the hook teeth.The hook teeth are the key structure of the spindle hooking and winding the cotton.Moreover,the hook teeth are in contact with the cotton plant,the bell shell,the sand,and hard particles during the operation of the cotton picker,leading to damage and peeling from the hook tooth coating.The failure of spindle hook teeth can be caused to couple with the complex and changeable field operating environment.The rear tooth tip and the tooth edge of the hook tooth were concentrated in the process of cotton picking or removal,due to the stresses of the front tooth tip.The wear in the hook tooth can often start from these parts,leading to the low wear resistance of the hook tooth.The electrolytic method can be used to passivate the front tooth tip,the rear tooth tip,and the tooth edge of the spindle hook teeth before the electroplating of the spindle,in order to improve the wear resistance of the spindle hook teeth,particularly for the service life and the collection rate of the spindle during harvesting.This study aims to explore the wear resistance of the passivated spindle and the cotton collection rate under field conditions.The unpassivated spindle and the passivated spindle were installed on different picking heads of the cotton picker.Once the working area of the cotton picker reached 0,150,300,450,and 600 hm^(2),two kinds of spindle samples were obtained and cut for sample preparation.The wear morphology of the hook teeth was analyzed to extract the wear area of the hook teeth and the thickness of the coating.The collection rate of the two kinds of spindles was measured after harvesting.The results show that the front tooth tip of the unpassivated spindle hook tooth was easy to break,whereas,the peeling of the passivation spindle hook tooth coating was later than that of the unpassivated spindle.There was a smaller wear area of the passivated spindle hook teeth,and the coating thickness was higher at the test position under the working areas.When the working area reached 600 hm^(2),the wear area of the unpassivated spindle No.1 hook tooth reached 8.8×10^(5)μm^(2),which was about 2.3 times of the passivated spindle No.1 hook tooth.There was the peeled-off coating of unpassivated hook teeth No.1 and No.2,as well as the passivated hook teeth No.1 at the test position.The passivated spindle performed better wear resistance,in terms of the wear morphology,wear area,and coating thickness.Furthermore,the collection rate of the passivated spindle was 0.2 percentage points lower than that of the unpassivated one.When the working area reached about 200 hm^(2),there was little difference between the collection rate two kinds of spindles.Once the working area exceeded 200 hm^(2),the collection rate of the passivated spindle was greater than that of the unpassivated spindle.When the working area reached 450 hm^(2),the collection rate of unpassivated and passivated spindles reached the maximum,which was about 96.4%and 96.7%,respectively.When the working area reached 600 hm^(2),the average wear area of the unpassivated spindle hook tooth reaches 2.9×105μm^(2),which was about 2.6 times of the passivated spindle hook tooth,and the collection rate of the passivated spindle was 0.5 percentage points higher than that of the unpassivated spindle,indicating the better picking performance of passivated spindle.The finding can provide great significance for the structural optimization and modification of the hook teeth of the cotton picker.