Научно-технические решения ранней уборки пшеницы на мелких площадях в условиях Узбекистана

Аннотация

The urgency and relevance of the theme of dissertation. At present around the worldwide on more than 215.4 mln. hectare land areas a grain is sown and from there in amount of 733 mln. tons of the grains arc produced. In effort to implement early and qualitative harvesting of grains it is considered as important to apply rcsourccs-saving, technical and technological modernization technical means. In due point of view the complex activities for on timely and qualitative harvesting of grains by preventing losses from the grains fields and sowing the secondly grown cultures after grains arc being performed. At high exceeding rainy regions the grain is harvested early by means of two-phase and three-phase harvesting technology. In this case the grains crops harvesting on small farm grains sown lands by applying the small-scaled technical means has special significance. Harvesting the wheat crops grown at the small land plots and the garden rowspacing farms and private ancillary farms by ways of well known methods, ways and means that require the more power, labor costs and those expenditures negatively will influence on the grains wheat quality and harvesting process. Till present time at the scientific researches for grains harvesting, the research activities for development of scientific-technical solutions in effort to harvest wheat earlier as well as substantiating the technical means being applied in it have not been performed sufficiently. In this case the special attention has the research results allowing early harvesting of crops by using less power-consuming and matcrials-consuming technical means in consideration of biological characteristics, physical-mechanical properties of the wheat and qualitative performance indicators of the harvesting. At a result we achieve that the wheat sown on the small land areas is harvested early, grains loss due to its crumbling will be avoided, initial high qualitative grains and straw, as well as the fields will get arranged for the second cultures cropping early. When implementing the harvesting works by the small-scaled technical means the expenditures for grains cleaning arc reduced. Due to above, the researches focused on the enhancement of wheat crops harvesting system, which is sown on small land areas, reducing the expenditures for power, materials and resources, increasing the performance quality, enhancement the technological process on early harvesting of grains cultures and substantiating the small-scaled technical means necessary for implementation arc actual matter. The present dissertation research at a certain level serves for implementation of the tasks, determined by the Presidential Decree of the Republic of Uzbekistan № 1758 dated May 21, 2012 year «About the program for further modernization, technical and technological re-equipment of the agricultural productions for 2012— 2016 years». The aim of the research work is the development and substantiation of parameters of the small technical means for reaping, threshing and cleaning the grains at early harvesting of the wheat at small fields in Uzbekistan conditions. Scientific novelty of the research work is as in the following: the enhanced designs of the small-scale power-resources saving reapers, threshers and grain cleaning machines arc substantiated and developed; the technologic mode of the segmental cutting instrument considering its bending resistance thrust is developed; the efficient ways of cleaning off the grain from a straw and empty glume in separator in the cleaning system of the thresher under the grains-straw substance in the separator under the digital operating elements influence as well as under the airstreams influence and sieve with mounted straw hooking devices, changing the grain substance in the threshing process; the new technical solution for intensification of grains cleaning off from weed mixtures by a way of its equal distribution to the sucking pipeline and sieves as well as the strengthening by transverse-longitudinal oscillations at the grains cleaning machine sieve is worked out. analytical dependencies allowing to determine design-engineering, cinematic and technologic parameters of the reaper, thresher and grains cleaning machine operating elements as well as the optimum parameters of the working organs of current technical means arc determined; improvement the harvesting quality of grains substance, decrease of the grains losses and increase of its purity at the optimum appearances, parameters and running modes of the operating elements of the reaper, thresher and grains cleaning machine arc determined; CONCLUSION 1. In effort to implement earlier harvesting of wheat crops for the purpose of fast releasing off the fields for sowing the secondly cultures at farms’ and peasants who has small land plots, on which it is impossible to apply combines, and it is reasonable to apply implementation reaping the grains crops at waxen matured period followed by its threshing and in a purpose to reduce the expenditures it is reasonable to apply small-scaled technical means in reaping and threshing of grains substance as well as the grains cleaning. 2. It is determined in the course of harvesting the wheat at the event when the grains moisture is below 38 % in spite of (8-9 days) early harvestings the grains’ crops maturing will be normal and mass of 1000 grains forms 38^42 grams. Herewith it is identified that the length of wheat stalks averagely will be within 72,5-78,1 sm, productivity on grains mass 71,3-117,7 c/ha, on grain 30,4-56,3 c/ha, but correlation grain to straw 1:1,2-1:1,4. 3. In the course of earlier harvesting of wheat the stalks’ moisture will be much higher, and in such conditions it is expedient using the reapers with segment cutting device and in effort to get qualitative and even cutting the grain stalks the slopping angle of the segment (г) cutting part must be less than stalks friction angle (cp ) and angle (/z) between the velocity directions of reaper and absolute velocity knife (the segment), in a purpose to form suitable singletree for harvesting the seizure width of the reaper 1,5 m is reasonable, as well as for prevention of the leaving on field high and uneven harvested field the reaper velocity must not exceed 1,0 m/s but cutting height - 5-10 sm. 4. Base on the developed mechanical-mathematical model and the analytical dependencies as well as the results of implemented experiments it was identified when capacity of thresher is 1,0-1,5 kg/s for threshing the grain mass with most threshing completeness at smaller crushing of grains, the following will optimum width of input window must be 0,33 m, diameter of thresher drum £>^=490 mm, frequency of the drum rotation «,/=720 min'1, quantity of rasp-bar rows Z,=4 rows, clearance between drum and deck Sg= 10 mm. 5. In effort to get completely fledged separation of grain from a straw at the thresher separator it is recommended to ensure helical location of finger-typed operating elements throughout the rotor surfaces in 4 rows as well as frequency of the rotor rotation n,=600 min'1, fingers quantity Z}=44 pieces, its length I =100 mm, wrapping angle of the deck aw =160°. 6. It was determined by the obtained mechanical-mathematical model and the analytical dependencies at the grains cleaning part of the thresher when the opening angle of jalousies is 30° and the velocity of fan airstreams is within 3,0-4,0 m/s, the distance between the self-hooking fingers device is 47,5 mm at that time the grains movement throughout the jalousie surfaces to inside, but the straw to outside will be ensured. 7. In the course of implemented single-factored and multi-factored experiments it was identified that when frequency of the selected fan rotation is «/=800 min'1, the frequency of the sieve oscillations £=145 min'1, the oscillations amplitude 4o=40-45 mm, opening angle of jalousies aj=30(), the distance between self-hooking fingers device £/=45 mm, its length ///,=15 mm at the grains cleaning part of the thresher the grains cleaning will be provided at the level of set requirements. 8. In the course of theoretical researches it was identified when the roller seizure angle is below 40° and clearance between them is 3-5 mm as well as frequency of its rotation is nr=l 50-200 min'1 there can be reached supply of the sufficient number grains substance into suction pipeline and grains cleaning machine sieve. 9. It was determined that sieves were strengthened except longitudinal oscillations as well as transverse oscillations and it will intensify the grains pass through sieve holes and in this case the movement velocity of grains must be below K„,a^.=0,0042 m/s. 10. In effort to get the qualitative harvesting of grains in grains cleaning machine it is expedient in running the machine to ensure following conditions when the roller diameter is 100 mm, clearance between them 3-5 mm, frequency of the their rotation 200 min'1, frequency of the fan rotation 2000 min'1, frequency of the sieve oscillations 140-175 min'1, amplitude of the longitude oscillations of sieve 30 mm and amplitude of the transverse oscillations 5 mm as well as its slopping angle is 14°. 11. Application of the developed small-scaled technical means at small land plots of farms’ and peasants allows to harvest the crops for 8-9 days earlier for releasing the fields for the secondly sown cultures, reduce the operational expenditures in reaping process, grains mass threshing and grains cleaning in comparing with traditional power consuming and materials consuming technical appliances, and in this case the economic efficiency will amount 14.3 mln. UZS in a year will be achieved.