Preview

Agricultural Machinery and Technologies

Advanced search
No 3 (2016)
View or download the full issue PDF (Russian)

ECOLOGY

43-48 572
Abstract
Researches of scientists of the Northwest Federal District of the Russian Federation and the European countries are directed on decrease in an environmental pressure of agricultural production on environment. The international projects BaltHazar, ERAB, BASE, Luga Balt are completed together with the leading foreign experts with support of the ministries of agriculture and environmental protection of Finland, Sweden, Denmark, Germany and other countries. The greatest negative impact on environment proceeds from systems of processing and use of manure and poultry litter. The main threat is posed by losses of biogenous elements, first of all nitrogen and phosphorus that can be connected by imperfection of technologies and lack of ecological management at the enterprises. The generalized ecological indicator of agricultural enterprise work is the effectiveness ratio of nutrient utilization. A decision-making technique on ecologically safe placement and functioning of agricultural enterprises was offered. The authors defined values of losses of biogenes during the main technological operations of processing of manure and poultry litter, developed mathematical model for definition of losses of biogenes at stages of a production cycle of bioconversion of waste of animal industry. The least losses of biogenes are reached at technology of of manure or poultry litter processing with use of the bioreactor of drum type on which patents for useful model are taken out. The generalized indicator of an environmental pressure of a livestock enterprise is the calculated value of balance of nitrogen and phosphorus. According to requirements of the Helsinki Commission (HELCOM) limitations of introduction of nitrogen no more than 170 kg/ha and phosphorus no more than 25 kg/ha are accepted.

PROBLEMS AND DECISIONS

3-6 572
Abstract
In the conditions of global economy social and economic development of Russia faces a number of long-term challenges. The most important of them is the low level of competitiveness and production efficiency. The low level of state support which several times is less, than in the West is the main reason for insufficiently high efficiency of agriculture. The high level of import of material resources and agricultural machinerycreates serious risks for competitiveness of domestic agrarian and industrial complex. Food import into Russia was considerably reduced as because of crisis response measures. Production of tractors, combines and other agricultural machinery increased thanks to significant rise in subsidies to agricultural engineering. A situation in agriculture can be change only on the basis of technological modernization, revival of domestic agricultural mechanical engineering, establishment of a network of the training centers, science and technology parks and technological platforms. For this purpose the special industry program of development of agricultural mechanical engineering is necessary.
7-11 522
Abstract
The autors proved the directions of resource-saving with regard to basic agricultural machinery: combine harvesters and tractors of classes 3 and above. The analysis has shown advantages of track laying vehicles in interaction of technogenic processes with productional agroecosystems. These advantages provide to track laying vehicles high technological need for agrarian and industrial complex in comparison with wheel machines. One of options of completing of the machine and tractor units (MTU) is use of multioperational trailing implements and a continuously variable ratio hydraulic drive of a undercarriage. To provide a turn of MTU with the minimum size of a rotary strip it is necessary to use mounted equipment more widely. The authors offered to equip tractors with two (forward and back) separate power takeoff shafts. The model of new generation of mobile power means MES-5300 with two mounted soil-cultivating implements on forward and back mounted systems, and also model with the mounted fodder harvesting adapter and the trailed implement on back mounted system is developed for soil preparation for winter wheat sowing. Due to the special technique it is possible to determinate technical and economic efficiency of the new design machines. If parameters of new machine by 1.2-1.3 times exceed the characteristic existing (basic) one, then we talk about usual modernization; excess by 1.5-1.8 times indicates deep modernization. And advantage by 1.8-2.3 times allows to refer new design to a class of innovative machines. The number of the integrated operations when using multioperational equipment on the basis of MES of the fifth generation is equal 17, when using modern technology on the basis of a tractor of the fourth generation - 27. As result the general capacity of equipment of the fifth generation increases by 20 percent.

NEW TECHNICS AND TECHNOLOGOES

12-16 477
Abstract
A choice of the sizes and form of a disk is made for the set operation conditions on the basis of geometrical ratios between parameters of a disk and their admissible values developed by practice. Except the crumbling and turning ability of a disk the add factors influencing on its geometrical and power parameters are non-crumple condition of a vertical wall of a furrow and steady raising of layer on a curvilinear surface of operation sector. Basic data for construction horizontal, cross-vertical, longitudinal-vertical projections is diameter of a disk, an angle of attack, running depth. Depth of the course images a chord of disk dip on cross-vertical and longitudinal-vertical projections of a disk. The disk sphere which excludes crumple of a vertical wall of a furrow at its movement is designated on the horizontal projection. Criterion of disk efficiency a is possible soil sliding along a curve of longitudinal-vertical projection within limits of the lowermost point and a point excluding crumple of the furrow vertical wall and located on a chord of deep. The parameter of a curve of possible sliding can be defined taking into account that the sum of multiplications of tangent efforts to a projection of a trajectory of the movement of an elementary platform less than zero. Taking into account the received value we can construction the sliding curve on the longitudinal-vertical projection in a zone of operating surface. Points of intersection of the sliding curve with the generating lines of longitudinal-vertical projection are moved by horizontal transfer on a piece of an interval of the horizontal projection. On three points we create a profile of a disk on height of a placement of the generating lines. The disk profile with the spherical or flat bottom should be create at the level of generating lines of cross-vertical projection taking into account the intervals placed on a perpendicular to the center of diameter of a disk of a horizontal projection.
17-20 590
Abstract
Weather conditions in flax cultivation areas during harvesting time can be characterized with high rainfalls, relative humidity and, in some areas, extremely low temperature. Clogging of fields with stones, grass germination through flax swaths, often an absence of homogeneity on length and thickness of straw in swaths require working out new devices for straw lifting. Existing devices for picking up do not provide a high-quality lifting of flax swaths and have a low coefficient of reliability of the process. Researches and experimental-design works were carried out to create a constructive-technological scheme of the picking up device of cylindrical type with spring-loaded rigid pins. The mathematical model of the device operation when a pin touching an obstacle. The condition of balance of the mechanism under which the pin of a cilinder will operate technological process of picking up of retted flax straw without action of the safety device (spring) was described. The offered method of calculation of operation of this device was introduced in a common flax swath lifter-turners
21-25 602
Abstract
High-quality soil cultivation for potato planting increases its productivity and allows to reduce damageability of tubers when harvesting. At its growing intensive complete or strip soil pulverizationl, formation of ridges or seedbeds for planting and growing are required. For performance of each method machines of different type, including various tillers, tilling ridge or seedbed formers, are used. The authors offered a multipurpose tiller with the horizontal rotor aggregated with tractors of classes 1.4 and 2. At readjustment the tiller operatest the main methods of soil cultivation necessary at potato growing: complete prelanding tilling, ridges or seedbeds formation for planting, cultivation of them at care of seedlings, loosening of an underlying layer in strips of the formed ridges or seedbeds under planting rows. This tiller has some constructional features: the tiller rotor with removable sections of flat L-shaped teeths allowing to operate complete and strip soil cultivation at a depth of 12 cm; the disk furrow shaperы regulated on depth and operating width; removable hoes for loosening of the lower layer of soil at depth of 22 cm under planting rows; a replaceable deflector with a direct back edge and (or) with a removable furrow shapers; basic wheels movable from a forward girder onto sidewalls behind - when seedbeds forming. The authorsreport the main agrotechnical requirements to the methods of complete prelanding tilling, ridges and seedbeds forming which are carried out by a tiller and cultivation of them when planting. The tiller has different complete set options for performance of these methods. Use of the offered tiller provides high-quality performance of methods of soil cultivation and potato growing and by 2-3 times reduces a range of necessary machines and costs of acquisition of them.
26-32 577
Abstract
Among the innovative modes of seeds and grain drying the priority belongs to the oscillating one. But the modes with periodic lying allowing to increase significantly efficiency of seeds and grain drying including the increased moisture are least studied. Researches of moisture transfer are necessary for justification of the modes of safe and intensive drying. Realization of these modes allows to define heat-transfer coefficient and lying periods duration. It is caused by need of decrease in a gradient of surface moisture content and temperature of grain. Drying duration can be defined by equation which enter diffusion coefficient, the caryopsis radius, hull thickness (the dehydrated zone) and the size of moisture content of a kernel and a hull. After moisture evaporation intensity and safety of drying decrease therefore the lying is necessary for moisture redistribution. Under certain conditions width of an evaporation zone turns out to be much less characteristic size of the dried-up body so this zone can be replaced, for example, with grain hull thickness. On the basis of an admissible moisture removal and density of a thermal stream at intensive drying analytical expression was received. It can be used for calculation of the maximum heat-transfer coefficient and, respectively, of the drying agent speed which depends on its height, a specific surface of grain and a share of the warmth required for moisture evaporation. For conditions of drying of grain in the grain dryers the speed of the drying agent should not exceed 0.6 m per a second. The authors defined values of admissible size of heat-transfer coefficient (no more than 40 W per sq. m in terms of one degree) and lyings duration which is equal 10 min. The ratio of duration of the period of heating and cooling of grain is equal 10:10, optimum value of this ratio is 15:20.
33-36 566
Abstract
Development of ecodegradable materials and use of them in innovative technology of sowing of seeds of grain crops in a tape isan important and actual problem of polymeric chemistry. Material is affected by programmable destruction under the influence of natural factors taking into account the biochemical processes in a plant. At the present time in literature there are no the data about polymeric materials which can operate plants biochemical processes when contacting to root system of directly in the soil. The authors developed compositions on the basis of synthetic polymer - low density polyethylene (LDPE) and biodegradable polymer - a polylactide (PLA). Thermophysical properties of ecofilms change under the influence of ultra-violet radiation. Photooxidation leads to cracking of samples with the raised maintenance of PLA. Temperature of melting of PLA decreases from 165 to 152 degrees Celsius (in some compositions to 137 degrees) and crystallinity degrees lower on average by 20 percent. Thus the most considerable decrease in crystallinity (about 30 percent) is noted in composition with a ratio of components of 50:50 mass percent. A composition formulation affects on the speed of destructive influence of moisture and an ultraviolet. The speed advantage of these processes is characteristic for the compositions containing from 30 to 60 mass percent of PLA. The soil samples with the maintenance of PLA more than 30 mass percent will be in less time exposed to biodegradation. Composition 50:50 has the greatest loss of weight equaled 18 percent. For other samples relative loss of weight makes 5-10 percent. The test for biodestruction showed considerable change of properties of polymeric samples of PLA- LDPE depending on mix composition. It means that it is possible to select such ratio of components at which material properties would conform to requirements imposed to agricultural appointment films.
37-42 536
Abstract
During a sowing grain is damaged because of movement on a surface of working elements. It leads to formation of cracks, to destruction and damage of seed material and as result productivity reduces and received grain has lower qualityof. The authors researched a movement of caryopsises during a sowing taking into account the speed of the movement, weight, friction and resistance forces, and other factors. At the movement on a distributive plate of a disk coulter seeds meet the cylindrical pins and change the direction of the movement that makes it possible the uniformity distribution. Their coordinates during each certain period of time were determined by system of the recurrent algebraic equations. Thanks to this system it is possible to define at each stage an arrangement of caryopsises, a trajectory of their movement after contact with pins. The main advantage of such method is that on each step it is possible to know the provision of a particle and to change the direction of a trajectory of its movement if it will be necessary. This problem was solved numerical due to the program «Plastina. For a plate with width 0.075 m and length 0.175 m long, by a step of time 0.0001s the authors made the cyclic procedure describing a trajectory of the particle movement. To define the further direction of a trajectory of the movement of a particle after its collision with an obstacle the authors applied probabilistic approach and invoked a random number generator. We studied a form of a distributive plate after modeling of the movement of a particle. The optimum position of seeds on a distributive plate with pins covered with rubber material reduces damage of caryopsises, improves their quality that provides optimum placement in soil at sowing


Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.


ISSN 2073-7599 (Print)