油菜联合直播机组合式船型开沟器设计与开沟质量试验

针对冬油菜机械化播种需开畦沟避免渍害的要求,解决长江中下游地区土壤黏重板结、含水率波动大,导致播种时同步开畦沟的稳定性难以保证的实际问题,设计了油菜联合直播机开畦沟系统,提出了一种配合铧式前犁完成开畦沟功能的组合式船型开沟器。根据土壤切削、挤压和犁体曲面形成原理,分析了组合式船型开沟器的触土曲面力学特性,确定了其主要结构参数。以工作幅宽为2 300 mm的2BFQ-8型油菜联合直播机为试验平台,对铧式后犁、船式开沟犁、组合式船型开沟器3种不同结构型式开沟器,在平均土壤含水率为21.4%、31.4%、46.6%,与之对应的平均土壤坚实度为1 320、846、539 k Pa的3种工况下的稻茬田开展了开畦沟性能比较试验,并测绘畦沟沟型断面。试验结果表明:3种工况条件下,组合式船型开沟器均能开出沟宽244.0~271.7 mm、沟深194.0~229.5mm的梯形沟,沟宽和沟深稳定性系数均达90%以上。开沟后种床带厢面宽度稳定,宽度达2 039.0~2 051.5 mm,满足油菜种植开畦沟的农艺要求。

Design and Ditching Quality Experiment on Combined Ship Type Opener of Direct Rapeseed Seeder

Considering the facts that the winter rapeseed is vulnerable to waterlogging, the furrow should be ditched while mechanical planting. The soil of middle and lower reaches of Yangtze River is sticky and its moisture content fluctuates greatly, which leads the stability of the furrow difficult to be guaranteed at the time of planting. In order to solve the above problems, the design of ditching furrows system for direct rapeseed seeder was carried out, and a combined ship type opener was proposed to achieve ditching the furrow. According to the principle of soil sliding and plow forming, the main structure and technical parameters of combined ship type opener were analyzed and determined. Based on the 2BFQ-8 direct rapeseed seeder whose work width was 2300mm, the ditching performance experiment on rear plow, ship type plow and combined ship type opener was carried out in rice stubble field, whose moisture content was 21.4%, 31.4% and 46.6%, soil compactness was 1320kPa, 846kPa and 539kPa. The furrow sections of furrows were mapped. The ditching performance experiment results indicated that shape of furrows ditched by ship type opener were more stable than that ditched by rear plow, and the width of seed bed which measured after ditched furrows by ship type opener was stable . The width and depth of furrows which ditched by combined ship type opener was 244.0~271.7mm and 194.0~229.5mm, its width stability coefficient and depth stability coefficient were more than 90%. The width of seed bed after ditching was 2039.0~2051.5mm. The experiment result revealed that the furrows ditched by combined ship type opener satisfied the actual production requirements of ditching furrows. The research conclusion had great theoretical value and practical significance to the design of opener which worked under the condition of soil with high moisture content.