Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture

Nanjing, China

Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture

Nanjing, China
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Cui S.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Cao G.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Zhang W.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Zhu X.,Changchai Company
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2014

In mechanical rice transplanting, hill-row spacing combination directly influenced the growth and yield of rice. To compare the effect of hill-row spacing on mechanical transplanting rice, the growth and yield of rice, we set up 2-year field experiments located in Zhangjiagang, Jingjiang and the Yellow Sea farm in Jiangsu Province, separately. The rice breed planted in Zhangjiagang, Jingjiang and the Yellow Sea farm was Wuyunjing 29, Wuyunjing24 and Lianjing 7, separately, all of which were japonica hybrid rice. There were 3 row-hill spacing treatments in-at each site, which the row spacing by hill spacing was 30 cm by 11 cm, 25 cm by 14 cm, 25 cm by 11 cm, each repeated 3 times. By the influence of the spacing, the area of 30 cm by 11 cm (row spacing by hill spacing), 25 cm by 14 cm (row spacing by hill spacing) and 25 cm by 11 cm (row spacing by hill spacing) was 135 m2, 150 m2 and 150 m2, separately. At the same site within each treatment, only the row-hill spacing differences were the mutation factors, the other factors were controlled. The effect of the mechanical transplanting rice, the tillering dynamics of rice, yield and yield composition of rice were tested. The effect of mechanical rice transplanting measured immediately after transplanting. 200 continuous points were taken in each area; the number of plants per hole, seedling injury and inverted were recorded to calculate the average number of plants per hole, drain planting rate, seedling injury rate and seedling inverted rate. To determine the tillering dynamic, the number of tillers was counted every 7 days from rice transplanting to the full panicle stage, 20 points for each plot were fixed. Actual yield of rice was determined after ripening. For each treatment, 3 m2 of rice were weighed after harvesting to calculate the actual yield, repeated 3 times. According to the average number of plants per hill, 3 hill plants were selected for testing, and then the yield component and the theoretical yield of rice were calculated. SPSS17.0 and Excel 2007 were used for the statistical analysis. The results are indicated below: 1) Drain planting rate of 25 cm by 14 cm (row spacing by hill spacing) was the lowest, then was 25 cm by 11 cm (row spacing by hill spacing), 30 cm by 11 cm (row spacing by hill spacing) was the highest. These indicate that narrow row spacing large hill spacing was conducive to reducing the drain planting rate of rice. No rule was found from the rates of seedling injury and inverted in between these 3 breeds. 2) The number of tillers after tiller stabilization of 30 cm by 11 cm (row spacing by hill spacing) was the highest, and then was 25 cm by 14 cm (row spacing by hill spacing), 25 cm by 11 cm (row spacing by hill spacing) was the lowest. These indicate that large row spacing and hill spacing is conducive to the promotion of rice tillering. 3) In the aspect of the yield components, ears of 25 cm by 11 cm (row spacing by hill spacing) were the highest, and then were 25 cm by 14 cm (row spacing by hill spacing), 30 cm by 11 cm (row spacing by hill spacing) was the lowest. No rule was found between the grain numbers per spike, the seed rate and 1000-grain weight. Finally in the aspect of the theoretical rice yield and the actual rice yield, 25 cm by 11 cm(row spacing by hill spacing) was the highest, and then 25 cm by 14 cm (row spacing by hill spacing), 30 cm by 11 cm (row spacing by hill spacing) was the lowest. The theoretical rice yields of 25 cm by 11 cm (row spacing by hill spacing) were 9.68%-26.5% higher than 30 cm by 11 cm (row spacing by hill spacing), and the actual rice yields of 25 cm by 11 cm (row spacing by hill spacing) were 3.18%-20.6% higher than 30 cm by 11 cm (row spacing by hill spacing). The 25 cm by 11 cm (row spacing by hill spacing) row transplanter should be more suitable for mechanical rice planting in Jiangsu Province. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.


Zhou L.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Zhou L.,Nanjing Agricultural University | Zhang L.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Ding W.,Nanjing Agricultural University | And 2 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2015

It is difficult to transport pesticide droplet into tree canopy and deposit onto opposite of foliage. In order to solve these problems, air-assisted and electrostatic spraying was proposed. Air-assisted electrostatic spraying is a new pesticide application technology combined air-assisted spraying and electrostatic spraying technology. The charged droplets transport and deposit under theair drag force and electrostatic force, which improved the charged droplet penetration ability and deposition within the crop canopy. The influencing factors of air-assisted electrostatic spray include induced voltage, spray distance, air velocity and spray pressure. To clarify the factors influence on spray coverage. Induced voltage was set 0, 3 and 6 kV; Spray distance was 0.5, 1, 1.5 m; Axial fan frequency was 30, 40, 50 Hz; Spray pressure was 0.3, 0.4, 0.5 MPa. CCD (central composite design) and RSM (response surface methodology) were employed to analysis the four factors at three levels. 29 group tests were conducted, which include 24 group analytical factors, 5 group error estimations. Design Expert Version 8 software (Stat-Ease Inc., USA) was used for experimental design, data processing and statistics. Response include positive coverage, opposite coverage and the ratio of opposite and positive coverage. The three response surface models were established by quadratic regression, model determination coefficient was 95.14%, 93.68%, 93.95% respectively. Aiming at the ratio of opposite and positive coverage and opposite coverage maximum, positive coverage less than or equal to 50%. Response surface model was adopted to optimize the working parameters at the constraint condition of induced voltage X1=6 kV, fan frequency X2 ∈ [30, 50] Hz, spray distance X3 ∈ [0.5, 1.5] m and spray pressure X4 ∈ [0.3, 1.5] MPa. At the same time, the models were validated at this condition, and the positive predictive coverage was 50%, the negative coverage rate was 3.69%, the ratio of opposite and positive coverage was 7.52%. The relative error was 4%, 9.25%, 16.26%, respectively. The results showed the ratio of opposite and positive coverage's influence factors ranked from large to small wasthe induced voltage, fan frequency, spray distance and spray pressure. Opposite coverage's influencing factors ranked from large to small wasinduced voltage, spray distance, spray pressure and fan frequency. Positive coverage's influencing factors ranked from large to small was spray distance, spray pressure, fan frequency and induced voltage. The charged droplets were mainly affected by the air drag force and electrostatic force. The interaction among fan frequency, induction voltage, spray distance had significant effects on the response surface model. Reasonable working parameters can improve negative droplet coverage. The study can provide the basis data for design of air-assisted electrostatic spraying machine and operating parameters choose. © 2015, Chinese Society of Agricultural Engineering. All right reserved.


Zhou L.,Nanjing Agricultural University | Zhou L.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Zhang L.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Xue X.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | And 4 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2016

In order to reduce the decay of the droplet carrying capacity and increase the droplet coverage on hidden area of the foliage, a double air-assisted electrostatic spraying system which included anelectrostatic nozzle, a centrifugal blower, an axial fan and a diaphragm pump was proposed in this study. The power of double air-assisted electrostatic orchard sprayer was from power take off (PTO) of tractor to drive hydraulic pump (CBH-G563-AFHL).There were three hydro-motors in hydraulic system to drive centrifugal blower, axial fan and diaphragm pump separately. The indoor and outdoor tests including charge to mass (CTM), air velocity distribution, vertical distribution of spray volume and canopy droplet coverage was conducted. The faraday cylinder was used to collect spray volume, Key sight 34 410 A digital multi-meter was used to test current, and the CTM was calculated. The result showed the CTM at 0.2 m was reached to 1.0 mC/kg with damping along air direction, but the current could also be tested at 1.8 m. The air velocity distribution, vertical distribution of spray volume was based canopy biomass of spindle type fruit, the two maximum heights were between 0.5 and 1.5 m. The field experiment was carried out in Shanxi during October 14 to 16, 2015. The objective of this experiment was to evaluate the effect of electrostatic charge on foliar spray deposition in a high spindle apple orchard using the double air-assisted electrostatic sprayer. The temperature was 25℃, relative humidity was 55%. Experiment plot was a modern standard apple orchard which was 350 m long and 200 m wide, the tree was spindle type apple fruit, three years older, 3.2 m in height, 3.5 m row spacing and 1 m spacing in the rows. Trimming was done every year after harvest. There are iron wires at 0.5,1.5 and 2.5 meters high which had different canopy width of 1.0, 0.6, and 0.3 m, and the foliage density was 7.8, 3.6, 1.97 m. The test was strictly followed the quality of air-assisted orchard sprayer (GB/T 24683-2009). The electrostatic system was switched on and off, in order to evaluate its effect on deposition on exposed and hidden face of the foliar. The flow rate at the nozzles was maintained unchanged across the tests, and the main environmental parameters were measured during the tests, they were air temperature, wind speed, and relative humidity. The water sensitive paper as collectors, the profile sampling strategy was adopted. The sprayer's working velocity was set at 0.84 m/s, spraying pressure was 0.5 MPa, rotation rate of axial fan and centrifugal blower were 1 400 and 1 800 r/min. Each test condition was replicated three times in the same position. Experimental plot consisted of four adjacent rows sprayed under real conditions, i.e. by passing with the sprayer in all the three inter-rows; foliar sampling was carried out in the central inter-row. Blocks were separated by three unsprayed inter-rows in order to avoid possible overlapping due to spray drift. The test was conducted to determine effects of electrostatic spraying on hidden droplet coverage and droplet distribution on canopy. All statistical analysis and graphical representations were performed using Microsoft excel 2010. Results showed the droplet coverage on exposed and hidden foliage were 115 and 47 dot/cm2 at single spraying at the condition of the spray volume 3.5 L/min and driving velocity 0.84 m/s. This illustrated the single spraying was enough for insect prevention, and double spraying was suggest for preventing disease. The droplet coverage was improved 20% at the outside of tree closed to sprayer using electric spraying, while 7.2% was improved at the outside of tree away from sprayer at beyond. The research can provide technology support for air-assisted electric orchard sprayer designing and spraying standard setting. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.


Zhou L.,Nanjing Agricultural University | Zhou L.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Fu X.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Ding W.,Nanjing Agricultural University | And 3 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2015

In order to mechanize the pesticide application of fence-type fruit tree, enhance the droplet deposition in canopy and improve work efficiency, a combined disc air-assisted orchard sprayer was developed. The mechanism design theory and virtual prototyping technology were adopted to design the disc atomizer and combined spray execution device. Single impeller was put to use in disc atomizer design, and the diameter of impeller was 0.4 m. Six-step motors were included in the combined spray execution device for lifting, rotating and contraction, the rotating and lifting speed were 4 rad/s and 0.12 m/s, respectively. The adjustable range of spray height was from 3 to 4 m, and the hemi-spray width was adjustable from 2 to 3 m. So it was suitable for the fence-type orchard with row spacing of from 4 to 6 m. The container's capacity was 1000 L, and the spray volume was 51.63 L under the rated working pressure of 0.4 MPa. The distance of the run was up to 1500 m, and the work efficiency was 2 times of single spray. The average spray volumes of the 8 nozzles of disc atomizer were 807, 894 and 1020 mL/min under the pressures of 0.4, 0.6 and 0.8 MPa respectively, while the standard deviations were 7.4, 8.2 and 7.8. It showed that spray volumes of different nozzles had small change, while spray volume increased with the increasing of spray pressure. The droplet diameters at 0.5, 1, 1.5, 2, 3, 4, 5, 6, 7 and 8 m along the direction of range were measured by DP-02 laser particle size analyzer under the pressures of 0.4, 0.6 and 0.8 MPa. The droplet diameters were 140, 135 and 122 μm in the distance of 2 m from the nozzle. The maximum diameter was in the distance of 4 m from the nozzle. The diameter decreased as the distance increased when the distance was greater than 4 m, while the diameter increased as the distance increased when the distance was less than 4 m. Spray deposition in vertical direction was mainly between 1 and 2 m above floor, and the maximum deposition was between 1.4 and 1.6 m. The data offered the basis to confirm the spray distance and guide the installation of disc atomizer. The fan property was tested and the performance curve graphic was drawn. Frequency transformer, torque meter and wind velocity indicator were used. The results showed that air volume was greater than 1 m3/s, and static pressure was greater than 60 Pa when the speed was greater than 1300 r/min. The highest efficiency was 89% at 1400 r/min. Execution time of each executive unit per stroke was 51.3 s for up and down, 50.5 s for stretch and draw and 26.5 s for rotation. The field experiment was conducted in Taizhou, which strictly followed the quality standard of air-assisted orchard sprayer (GB/T 24683-2009). The row space was 4 m×2 m, the crown diameter of the tree was 0.7 m, and the height of the tree was 1.9 m. Three trees were randomly selected as sample trees. The intersection points of 3 horizontal layers and 3 vertical layers of each tree were set as sample points, with a total of 9 sample points for one tree. The result showed the pesticide was evenly distributed in the exterior of canopy, and the average coverage of the left and right were 55.13% and 52.60% respectively for the front of the leaf, and 6.57% and 7.14% respectively for the back of the leaf. The interior deposition was less than the exterior, but the spraying coverage was relatively even in the front and rear of the leaf, 12.77% and 9.74%, respectively. This study proposes a new machine of plant protection for the fence-type fruit tree, and also provides the reference for optimum design of orchard air-assisted sprayer. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.


Jin C.,Nanjing Agricultural University | Jin C.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Yin W.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Wu C.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2012

The rape windrower was a dynamic system that including many input and output variables. Windrow quality mathematical model was used to describe the correlation of windrowing and transporting. An analysis on the relationship of biological morphology, the maturity when rape windrowing, the structure parameters of transporting mechanism and windrowing mechanism were given. The effect degree of exhaust straw port on windrow quality during the winding was analyzed. The correlations of windrow quality with the velocity of machine moving, transportin device parameter and exhaust straw port parameters were made. The results of field test showed that rape in the height of 1.3-1.7 meters, and in the yellow ripe stage was much suitable for cutting. The ratio of reel pad peripheral speed and machine moving speed should be chosen in the range of 1.1-1.5. The ratio of conveyor belt speed and machine moving speed should be chosen in the range of 3.2-5.0. The working rhythm and speed of stalk on the conveyor belt controlled by the transverse stir device must be coordination with transporting speed of the conveyor belt. Under those conditions that mentioned above, the windrower could get the total loss of windrowing was less than 1%, the windrowing angle of rape stalk was less than 30°, the windrowing angle difference was less than 15°, and the windrowing quality could meet the requirements of the agronomy.


Xiao L.L.,Chuzhou University | Xiao L.L.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Hu Z.C.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Zhang H.J.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Wang W.,Chuzhou University
Advanced Materials Research | Year: 2014

According to exist technical problems and requirements of the air-suction peanut precision mulching film and punching planter, the new air-suction peanut precision dibbler of the planter' key working part was researched. It was introduced the composition and working principle of the dibbler. According to functional and technical requirements of the dibbler' main parts, the structural design and analyze were done. The dibbler mainly consists of roller body, cavitations' components, transmission system, and the air suction metering device. In the peanut growing typical region, field trial of the dibbler showed that overall performance is relatively stable, each component are operating smoothly, and the operating indicators can better meet the technical requirements. © (2014) Trans Tech Publications, Switzerland.


Shen C.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Li X.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Tian K.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Zhang B.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | And 2 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2015

Mechanical cutting and fiber peeling are important parts in the ramie production process, and its working process is the process of interaction between rigid body (machine) and flexible body (ramie stalk). To make the developed harvester and peeling machine to meet the working requirement of high quality, efficiency and low consumption, the premise is to get mechanical characteristic parameters of crop, to have a fundamental understanding of ramie harvesting and fiber peeling mechanism. Based on this, in order to provide the mechanical parameters and theoretical basis for the research on cutting and peeling ramie, experimental analysis on the mechanical model of ramie stalk has been made in the paper. The crop object for experimental analysis was the third crop of Zhongzhu No. 1 planted in Xianning Ramie Comprehensive Experiment Station of China Agricultural Research System (Bast fiber crops), the acquisition time was on November 2nd, 2013, and the test was conducted in Nanjing Research Institute for Agricultural Mechanization, Ministry of Agriculture, during November 5th to 15th, 2013. During the experimental research process, the geometric model for ramie stalk was assumed firstly. The cross section of ramie stalk was similar to the circle, which could be respectively divided into central medulla, xylem, phloem and green husk layer. The mechanical property in the central medulla and green husk layer might be ignored. The paper abstracted and simplified the geometrical shape, and presumed that the cross section was round with certain diameter. The material, diameter and wall thickness dimension of each fraction were even. After ignoring the central medulla and green husk layer, the geometrical shape of ramie was assumed as hollow pipe, made up of different kinds of materials including xylem and phloem. Secondly, composite mechanical theory was employed to construct mechanical model of ramie stalk. Elastic parameters that should be obtained from experiment were decided according to the assumption of ramie geometrical shape and experimental equipment conditions, as well as the calculation formula of each elastic parameter. Thirdly, PC-controlled universal testing machine was applied to make mechanical test, such as tensile, compressive and bending, to ramie stalk from each direction (axial direction and radial direction) and to each part (xylem, phloem and the whole stalk), to acquire mechanical parameter data. The universal testing machine used in the experiment was WDW-10 PC-controlled electronic universal testing machine with test power range 5 kN, and the accuracy of its force sensor and displacement sensor were both maintained within ±0.1%. In tensile test, xylem, phloem and stalk samples were 20 groups of rectangle samples about 80 mm long, 6-7 mm wide, material thickness thick. Plate fixture was used, and the clamped position was covered by gauze for protection. Pre-tightening force when starting was less than 5 N, test loading rate was 5 mm/min. Then, axial tensile stress-strain curve of each sample group was obtained. In compressive test, xylem, phloem and stalk samples were 10 groups of rectangle samples about 10-11 mm long, 5-6 mm wide, material thickness thick. Compressive test briquetting was used. Thus, radial comprehensive stress-strain curve of each sample group was obtained. In bending test, xylem and stalk samples were 10 groups of samples with the length of about 120 mm. The sample cross section was tube-shape, and external and inner diameter was decided by material conditions. Sample was placed between the support and pressure head of three-point bending test fixture. Span of the support was 80 mm, pre-tightening force when starting was less than 5 N, and test loading rate was 5 mm/min. Radial bending force-deformation curve was obtained. At last, all elastic parameters of ramie stalk mechanical model were obtained with analysis of test data. The radial compressive elasticity modulus were 9.73 MPa (stalk), 10.34 MPa (xylem) and 8.03 MPa (phloem); the axis tensile elasticity modulus were 466.17 MPa (stalk), 320.92 MPa (xylem) and 2409.22 MPa (phloem); the radial bending shear modulus were 39.77 MPa (stalk), 69.02 MPa (xylem) and 33.80 MPa (phloem), the axis torsional shear modulus were 3.74 MPa (stalk), 3.98 MPa (xylem) and 3.09 MPa (phloem), the Poisson's ratios of plane XZ of each parts was assumed to 0.3, and the Poisson's ratios of plane XZ and the Poisson's ratios of plane XZ were equal, the values were <0.0269 (stalk), <0.0451 (xylem) and <0.0043 (phloem). Meanwhile, the test results of paper showed that the axial tension of ramie stalk played the load-bearing role much more in the xylem, and the adhesive force in the phloem and xylem was incapable to prevent the phloem from sliding along the surface of xylem; the measurement value of elastic parameter in the radial direction of ramie stalk was closed to the calculated value gained by calculating the elastic parameters of each fraction, and the radial direction of ramie stalk could match the characteristics of composite materials. In conclusion, the assumption of the composite model adopted in the experiment is reasonable, and experimental analysis results can be applied into subsequent related researches. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.


Shen C.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Li X.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Zhang B.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Tian K.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | And 2 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2016

In order to provide optimal theoretical cutting parameters of ramie stalk for ramie harvester, the cutting test of ramie stalk was conducted on the self-designed test bench in this paper. The test studied the influences of different geometrical parameters of blade, cutting speed, and ramie stalk feeding speed of reciprocating single movable blade cutter and double movable blades cutter on the cutting performance. The 4 groups of common blades had 2 blade lengths (81 mm, rice & wheat harvester blade; 120 mm, corn harvester blade) and 2 blade edge types(smooth-edge blade and serrated-edge blade), and the blade widths of various groups were the same(76 mm, equal to the driving distance of cutter bar on the test bench). Therefore, 5 factors were designed in the test: cutting speed, stalk feeding speed, blade edge type, blade length, and number of movable blades. Evaluation indices determined in the test were cutting power and number of failed stubbles (not cut off or broken); the smaller the 2 indices were, the better the performance would be. Besides, a multi-index evaluation model was established in the test and the values of multiple indices were reflected by the comprehensive score. The higher the score was, the better the performance would be. Among the 5 factors, blade edge type, blade length, and number of movable blades were obtained through model selection, and they were fixed at 2 levels. Cutting speed and stalk feeding speed were continuous values and the optimal values could be selected within a scope. Therefore, the optimal parameters of the 3 factors at 2 levels were determined by adopting the method of multi-factor orthogonal tests, and then the optimal parameter combination was obtained through the quadratic regression orthogonal rotation tests taking the other 2 factors i.e. setting cutting speed and stalk feeding speed as experimental factors. In the multi-factor orthogonal tests, the factors with significant influences on cutting power were cutting speed(P<0.01), number of movable blades(P<0.01) and blade length (P<0.1) according to the significant degree. The combination of the optimal level was double movable blades cutter and short blade(81 mm) under slow cutting speed(1 m/s). In addition, stalk feeding speed and blade edge type had no significant influence on cutting power. Meanwhile, the factors with significant influences(P<0.01) on the number of failed stubbles were blade edge type, blade length, cutting speed, and stalk feeding speed according to the significant degree. The combination of the optimal level was serrated-edge blade and long blade(120 mm) under fast cutting speed(1.2 m/s) and slow stalk feeding speed(0.7 m/s). In addition, the number of movable blades had no significant influence on the number of failed stubbles. Besides, the factors with significant influences on comprehensive score were blade edge type(P<0.01), blade length, number of movable blades, cutting speed and stalk feeding speed(P<0.05 for the latter 4 factors) according to the significant degree. The combination of the optimal level was serrated-edge blade, long blade(120 mm) and reciprocating double movable blades cutter under slow cutting speed(1.0 m/s) and slow stalk feeding speed(0.8 m/s). Furthermore, according to the combination of optimal score in the orthogonal tests, this paper conducted the quadratic regression orthogonal rotation tests for the 2 continuously adjustable factors i.e. cutting speed and stalk feeding speed, investigated their influences on cutting power, cutting quality and comprehensive score as well as their interaction effect, and established the quadratic regression functions respectively. In terms of the cutting power, when the cutting speed was 0.878 9 m/s and the stalk feeding speed was 0.862 4 m/s, the 1 m-swath cutting power was 281.408 4 W, which was the minimum value. As for the cutting quality, when the cutting speed was 1.161 4 m/s and the stalk feeding speed was 0.711 7 m/s, the number of failed stubbles in 1 m2 area was 5.691 1, which was the minimum value. For the comprehensive score, when the cutting speed was 1.092 0 m/s and the stalk feeding speed was 0.722 9 m/s, the score was 86.718 0, which was the highest value. Finally, according to the test results, the optimal parameter combination of ramie cutting test in theory was: cutting speed 1.092 0 m/s, stalk feeding speed 0.722 9 m/s, reciprocating double movable blades, serrated-edge blade, and blade length 120 mm, and under the condition, the 1 m-swath cutting power was 318.814 5 W, the number of failed stubbles in 1 m2 area was 6.006 4. In conclusion, the optimal parameter combination of ramie cutting adopted in the experiment is reasonable, and the experimental analysis results can be applied into subsequent related researches. © 2016, Chinese Society of Agricultural Engineering. All right reserved.


Wu C.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Xiao S.,Hefei Academy of Agricultural science | Jin M.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2014

In order to find out the differences between two methods of rape harvest, i.e. combine harvesting and two-stage harvesting and to provide a reasoning basis for choosing mechanized harvesting method, the simulation contrast experiments of the two harvesting methods were carried out in this paper, and the economic coefficient, grain water content, stalk moisture content, loss rate and seed quality were tested at different harvesting times. Artificial simulation of combine harvesting means artificial direct harvesting (ADH). First, the rape was cut down from a randomized plot of 5 square meters in the field, moved to a threshing ground, and then threshed and separated by manual labor immediately. The total loss was the sum of those occurred in oilseed rape due to natural shedding, crop disturbance by human being, and threshing and separation losses. The artificial two-stage harvesting (ATH) means cutting down the rapes and picking up them in different periods. The rape should be aired for 4~5 days after cutting down, then threshed and cleaned by manual labor. The artificial simulation experiments showed that the seed loss of ADH got to 3.2%, 50.8% lower than that of ATH, 6.51%, and the oilseed qualities of the two harvesting methods had no obvious difference, however the oil content of ADH was slightly higher than ATH, while its protein content was slightly lower. Besides, the two kinds of mechanized harvesting experiments were carried out. Fifteen types of combine harvesters produced by 12 enterprises were put in use in the two-stage harvesting. The loss rate, broken rate, impurity rate and operation efficiency were measured. Except the impurity rate, the measurements of mechanized two-stage harvesting (MTH) were better than mechanized combine harvesting (MCH). Further more, economic efficiencies of the two harvesting modes were analyzed. The fuel cost, labor cost, workload in life period, depreciation cost, income of yield increase and comprehensive benefit in the lifetime were compared. The results indicated that the economic benefit of MTH was 361 yuan/hm2 higher than that of MCH. In addition, the two harvesting methods were comparatively analyzed based on the machinery performance, adaptability and some other aspects. The time of vacating field for the next crop could be about 4.8 days earlier in MTH. And it had widespread adaptability to various rapes and different harvest conditions, also had superiority in seeds storage and straw chopping because of the lower moisture content. However, finishing the swathing and picking up in two operations was one of the imperfections, and another was its relatively poor ability of adapting to cloudy day or continuous rain. MCH was relatively more convenient and had higher efficiency for it could finish harvesting in shorter time, but it didn't well adapt to different crop morphologies, and had high loss rate if the rape of improper breed was not gathered in time. The analyses indicate that the two harvesting methods have their own advantages and disadvantages and adapt to different regions and conditions, so the two methods will have further development in China, and should be chosen and used in accordance with local conditions.

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