棉秆粉碎及地膜随动集条机设计与试验

Design and experiment of cotton stalk chopping and plastic film master-slave strip collector

针对现有残膜回收机在棉田残膜回收过程中存在边膜回收难、回收残膜含杂率高的问题以及后续残膜捡拾打包运输的需要,该研究根据棉秆和残膜处理分段作业要求设计了一种棉秆粉碎及地膜随动集条机,可完成棉秆粉碎还田及残膜集条作业。将粉碎的棉秆被抛送至集条装置后方侧面交接行,解决了现有秸秆粉碎残膜回收联合作业时存在棉秆与残膜同时被捡拾的问题。以机具前进速度、秸秆粉碎刀轴中心离地高度和指盘入土深度为主要因素,以地膜集条率、秸秆粉碎长度合格率和残膜含杂率为响应值,进行三因素三水平二次回归试验,得到各指标的响应面数学模型,分析了各因素对作业效果的影响。结果表明,机具前进速度对地膜集条率影响极显著,指盘入土深度影响显著,秸秆粉碎刀轴中心离地高度无显著影响;机具前进速度和秸秆粉碎刀轴中心离地高度对秸秆粉碎长度合格率影响极显著,指盘入土深度无显著影响;机具前进速度和指盘入土深度对残膜含杂率影响极显著,秸秆粉碎刀轴中心离地高度影响显著。验证试验结果表明,机具前进速度为5 km/h、秸秆粉碎刀轴中心离地高度为340 mm和指盘入土深度为60 mm时,地膜集条率为94.5%,秸秆粉碎长度合格率为96.5%,残膜含杂率为20.2%,作业性能满足要求。研究结果可为棉秆粉碎及地膜随动集条机最佳工作参数的选择提供参考。

Mulch film has been widely used in large-scale agricultural production in recent years. The ever-increasing mulch film has covered various food crops from fruits and vegetables, indicating the largest coverage in China. The residual film can be accumulated to cause some risks in the soil, such as the microbial survival in the soil, the disruption of the soil agglomeration structure, the blocked water circulation, soil salinization, and consolidation. A residual film recovery machine can be commonly used for subsequent pickup, packaging, and transportation of the residual film. However, the high impurity rate of residual film often occurs in the recovery of side film during operation in the field. Therefore, the residual film has posed a major constraint on crop growth and development in sustainable agriculture. In this study, a combine machine with cotton-stalk crushing and film following strip collector was designed to realize the cotton stalk crushing and returning to the field, and concurrently the collecting stripe operation on the residual film. A cotton stalk chopping device and a conveying device were also designed to throw the crushed stalk to the rear side handing row of the stalk collecting device, according to the requirements of cotton stalk and residual film processing. As such, the stalk and residual film were picked up at the same time during the combined operation of stalk crushing and residual film recovery. A plastic film master-slave strip-collection device was developed to bring the side film up to the surface, and then to collect the stripe for a better pick-up and recovery rate of the side film. The finger discs were also arranged to determine the main structural parameters. A transmission system was then designed, according to the agronomic requirements. A three-factor and three-level quadratic regression test was carried out to verify the operation performance and reliability of the machine. Among them, the machine advance velocity, the shaft center height of stalk chopping cutter from the ground, and the depth of finger disc into the soil were taken as the test factors, whereas, the film collection stripe rate, the length pass rate of stalk chopping, and the impurity rate of the residual film were taken as the response value. The response surface mathematical model of each factor was obtained to optimize the influence of each factor on the operation performance. The results showed that the machine advance velocity had the highly significance effects on the film collection stripe rate, and the depth of the finger disc into the soil had significance effects,while the height of the center of the stalk chopping cutter shaft from the ground had no significance. The machine advance velocity and the height of the center of the straw chopping cutter shaft from the ground had the highly significance effects on the length pass rate of stalk chopping, and the depth of the finger disc into the soil had no significance effects. The machine advance velocityand and finger disc into the soil had the highly significance on the impurity rate of the residual film, and the height of the center of the straw chopping cutter shaft from the ground had significance effects. An optimal combination was achieved for the best operation performance, when the advance velocity of the machine was 5 km/h, the height of the center of the stalk chopping cutter shaft from the ground was 340 mm, and the depth of the finger disc into the soil was 60 mm. In this case, the film collection stripe rate was 94.5%, while the length pass rate of stalk chopping was 96.5%, and the impurity rate of the residual film was 20.2%. The finding can provide a strong reference for the optimal working parameters of the cotton-stalk crushing and mulch-film strip collector.