水旱两用秸秆还田耕整机关键部件设计与试验

为增加土壤的有机质含量,改善土壤的团粒结构,同时有效缓解秸秆焚烧难题,针对长江中下游地区麦-稻、油-稻等水旱作物交替种植的特点,设计了一种水旱两用型秸秆还田耕整刀辊。阐述了新刀辊的结构和工作原理,分析并确定了关键部件的结构参数,重点对传统旋耕刀的布置及其破茬理论进行了详细的分析。田间试验结果表明:水旱两用型秸秆还田耕整刀辊旋耕一遍即可实现水田和旱地秸秆埋覆、旋耕碎土、平整地表等多项功能,水田和旱地耕深分别为181.6~200.4和151.2~173.8 mm,耕深稳定性分别为92.4%~94.8%和92.4%~93.4%,耕后地表平整度均小于12 mm,植被埋覆率分别为96.3%~96.4%和90.6%~97%,碎土率为87.3%~89.6%和64.5%~90.2%,作业效果满足水稻播栽对耕整地的农艺要求。

Design and experiment on critical component of cultivator for straw returning in paddy field and dry land

Abstract: As the main producing area of rice, the Yangtze River basin usually had various multiple cropping systems, such as rape-rice, wheat-rice, green manure-rice, the double cropping of rice, triple-cropping. Rice is planted immediately after the harvest of the previous crop. So the straws are buried in the field in a busy harvesting and planting season. Crop residues incorporated in farmland by mechanical technique can improve soil physics properties and fertility, increase the yield and farm income. Straw returning to field practice can reduce the problem of crop residue burning and also the amount of chemical fertilizer application. Based on our previous research on the 1GMC-70, the cultivator for high stubble returning in paddy field, a new roller of cultivator for straw returning both in paddy field and dry land was designed. The helical rotary blades, bent blades and the IIT245 rotary blade were the main tillage parts of the machine, and its power consumption was an important technical parameter to consider for the overall performance. The former two types of blade are used to cut soil, while the latter one to bury straw. In this study, based on the roller structural and working principle of the main parts of the cultivator, the parameters of key components were tested for the rotary blades IIT245 and spiral blades. Furthermore, their interrelationships and interactions were analyzed in detail. An advisable arrangement of rotary blades IIT245 fixed on the rotor was provided. The tillage width was 2 000 mm. The rotor speed was 335 rev/min. The forward velocity was 0.7 to 1.1 m/s. The lower forward velocity was used in dry land, while the higher forward velocity was for wet land tillage. Experiments of crop straw burying rotary tillage were conducted repeatedly both in wet land and dry land. The field test showed when tillage in fields of soil compaction value under 1260 kPa at about 150 mm depth, the cultivator could realize the straw mulching and returning, soil crashing, and surface leveling at the same time. In details, , in the dry land and paddy field, the tillage depth of this cultivator was 151.2-173.8 mm and 181.6-200.4 mm, stability of tillage depth was 92.4%-93.4% and 92.4%-94.8%, field surface roughness was less than 12 mm, vegetation coverage rate was 90.6%-97% and 96.3%-96.4%, and soil crushing rate was 64.5%-90.2% and 87.3%-89.6%. The field test indicated that the cultivator possessed both the advantages of traditional rotary tiller for soil tillage and the developed products by our research group for high straw burying. The advantages included wide tillage width, deep tillage depth, high straw burying rate, high operational efficiency, easy tillage operation. In addition, it could also cut down on tillage time and save labors, which showed great superiority in the field of the straw returning back to farmland machine. Results of the research indicate the working qualities of cultivator met the agro-technical requirement of rice and wheat sowing and transplanting. It was suitable for tillage in middle and lower reaches of Yangtze River, where the principal crop rotation was wet land rice after dry land crop annually.