秸秆还田深松旋埋联合耕整机设计与试验

深松作业能有效打破犁底层,提高土壤蓄水保墒能力。秸秆还田是秸秆资源利用最为直接有效的方式,将2种保护性耕作方式结合在一起可大大提高作业效率。为了满足深松和秸秆还田同时作业的需求,设计了集土壤深松、破茬碎土、秸秆旋埋、平地等多功能于一体的深松旋埋联合耕整机。该机主要由自激振动深松装置和秸秆还田旋埋刀辊组成,自激振动深松装置可调节预紧力,不仅可以在一定程度上减少深松耕作阻力,还可以在遇到障碍物时有效保护深松铲,深松铲柄的设计利用了滑切原理,可有效切断秸秆和杂草,防止缠绕和堵塞深松铲,对旋埋刀辊进行了重新布置和优化,提高了工作稳定性和破土能力。田间试验表明深松作业可有效减小旋埋刀辊功率;在拖拉机1挡和2挡速度下深松旋埋组合作业总功率分别为单独深松和单独旋埋2项作业之和的85.0%和82.2%;深松旋埋组合作业下深松和旋埋的平均耕深分别为28.9和17.5 cm,耕深稳定性分别为93.5%和87.4%,秸秆埋覆率为92.0%,耕后地表平整度为1.0 cm,深松旋埋联合作业后的各项性能参数均超过质量评定指标,满足农艺要求。

Design and experiment of combined tillage machine for subsoiling and rotary burying of straw incorporated into soil

Abstract: Soil compaction become very serious problem due to many years of traditional tillage practices which result in formation of hard plow pan, shallower rooting depth, decreased air and water permeability, and confined root system development. Sub-soiling and straw incorporated into soil applied jointly result in good working efficiency, alleviation of plow pan by sub-soiling, improved water holding capacity and buried crop residue. This is direct and effective way of improving organic matter contents and it can also effectively alleviate the environmental pollution caused by straw burning. This practice will not only reduce wheel traffic in field, it also will save busy time in farming season and will play an important role in increasing crops yield and farmer''s income. Through the study of relevant literature, in order to meet the needs of deep tillage and straw burying at the same time, a multifunctional machine for sub-soiling and rotary burying have designed, which was capable of joint operations like sub-soiling, stubbles cutting, soil crushing, residue burying and leveling. Sub-soiling implement with self-excited vibration and adjustable pre-tightening force were devised in this machine which worked to reduce sub-soiling resistance to certain degree and also protected the subsoiler when it encountered obstacles. The principle of sliding cutting was adopted in the design of the deep shovel bar which can cut off straw and weeds effectively and prevented winding and clogging to the subsoiler bar. The stress analysis of the sub-soiling implement was carried out and the force formula was determined. Blades of rotary cutter were rearranged and optimized to improve working stability and soil cutting and crushing capacity. Sub-soiling provided good condition for rotary burying and the depth of straw embedment was increased. Different field tests such as separate sub-soiling, rotary burying after sub-soiling, separate rotary burying and sub-soiling with rotary burying as combined operation was carried out. The traction resistance and power consumption of implement under different working conditions were analyzed. Results showed that the traction resistance and power consumption of sub-soiling operation was greatly affected by the working speed. In the rotary burying operation, the driving force of the positive rotation of the rotary cutter roll was opposite to the working resistance so that the cancel out and the traction power consumption of rotary burying operation were small, and power ratio for rotary burying was more. Under the 1st and 2nd gear speeds of the tractor, the total power respectively for the combined operation of sub-soiling and rotary burying was 32.72 and 41.88 kW. They accounted for 85% and 82.2% of the total sum of individual sub-soiling and rotary burying operations, respectively. Through consulting relevant documents, compared with the traditional machine for sub-soiling and rotary tillage, the power consumption was reduced by 4.4% to 14.8% and 7.9% to 14.0%, respectively in the same working condition. Other parameters of experiment collected after combined operation of sub-soiling and rotary burying and statistically analyzed included average depth of sub-soiling. The results showed that rotary burying were 28.9 and 17.5 cm, respectively, sub-soiling tillage stability was 93.5% and rotary burying tillage stability was 87.4%, the average vegetation cover rate was 92%, the surface evenness after tillage was 1.0 cm, and soil resistance of 0-15 and 15-30 cm after tillage were 437.6 and 951.8 kPa, which were 78.4% and 67.4% less than that before tillage, respectively. Soil bulk density of 0-10 and 10-20 cm after tillage were 1.40 and 1.41 g/cm3 which decreased by 6.7% and 8.4%, respectively compared with that before tillage. The performance evaluation indexes of sub-soiling field preparation combine machine were compared, and the measured values of the above parameters for combined operation of sub-soiling and rotary burying exceeded the quality evaluation index and meet the agronomic requirements.