In agrotechnical practice, it was found that between qualitative indices, which express the sowin... more In agrotechnical practice, it was found that between qualitative indices, which express the sowing precision achieved by precision planters determined in the laboratory, and those determined under operating conditions, that there are certain differences, which are sometimes quite significant. The decrease in the value of the quality indices was manifested by the increase of the number of mistakes, either of the number of double planting holes (with at least two seeds), or of the number of missing planting holes. Both cases are unfavorable for the agricultural producer, generating production losses. This paper discusses the influence of the degree of soil grinding on sowing precision in operating conditions, by determining the spectrum of the vibrations induced in the mechanical structure of row units of a precision planter in contact with the soil of three different plots for three working speeds: 4, 6, and 8 km·h−1. Later, the vibrations were simulated under laboratory conditions, ...
In order to obtain a correct and always reproducible image of the performances achieved by a plan... more In order to obtain a correct and always reproducible image of the performances achieved by a planter (or any agricultural machine), laboratory tests are required, under specified conditions, well controlled, to determine the precision of sowing outside the optimal agricultural periods. The paper presents a theoretical model for estimating sowing precision (feed quality index) as a polynomial function of the second degree, dependent on seed norm per hectare, working speed, depression value, mass of 1000 seeds, as well as combinations thereof. REZUMAT Pentru a obține o imagine corectă și oricând reproductibilă a performanțelor atinse de o semănătoare de precizie (sau orice mașină agricolă) se cer inițiate încercări de laborator, în condiții dinainte precizate, bine controlate, pentru determinarea preciziei de semănat în afara perioadelor optime agricole. Lucrarea prezintă un model teoretic pentru estimarea preciziei de semănat (indicele de calitate al alimentării) ca o funcție polinom...
International Symposium ISB-INMATEH – Agricultural and Mechanical Engineering, 2018
In the past few decades, size and weight of agricultural machinery have increased significantly, ... more In the past few decades, size and weight of agricultural machinery have increased significantly, and as a consequence, the severity and depth to which the stress is transmitted into agricultural soil have increased. The objective of experimental determinations was to study the influence of some factors characteristics to compaction: tire inflation pressure, wheel load and contact pressure on the contact area between tire and soil, as well as 2D and 3D mapping of pressure distribution in the footprint. The front tire of the U445 Romanian agricultural tractor was tested at five tire inflation pressures: 100, 150, 200, 250 and 300 kPa, obtaining contact areas between 0.0252-0.0349 m 2 and contact pressures between 98-136 kPa. REZUMAT În ultimele decenii, mărimea și greutatea mașinilor agricole au crescut în mod semnificativ și, în consecință, au crescut severitatea și adâncimea la care se propagă tensiunile în solul agricol. Obiectivul determinărilor experimentale îl constituie studiul...
Precision for sowing is essential in order to achieve sowing quality works for hoeing plants, ult... more Precision for sowing is essential in order to achieve sowing quality works for hoeing plants, ultimately influencing the high productions obtaining. This paper presents a comparative study regarding the sowing accuracy obtained in laboratory conditions on a special stand, using 3 different row units: one individual transmission and two centralized transmissions for the seed distribution devices. The researches were developed for three working speeds, three different plant densities per hectare using corn as seed material.
This paper presents issues related to static testing of protective agricultural equipment structu... more This paper presents issues related to static testing of protective agricultural equipment structures and includes a description of the tested structure, the testing method, the testing conditions and the obtained testing results and those analyses. The protection structures along with the safety belt are designed to reduce the risk of injuring the operator in case of overthrow / rollover or accidental collisions of the agricultural equipment. The attempts for checking the mechanical strength of protective structures from agricultural operator machinery, are concerned with checking the protection degree that these structures assures the driver in case of overthrow / rollover or accidental collisions when operating or machinery is in transport mode.
In agrotechnical practice, it was found that between qualitative indices, which express the sowin... more In agrotechnical practice, it was found that between qualitative indices, which express the sowing precision achieved by precision planters determined in the laboratory, and those determined under operating conditions, that there are certain differences, which are sometimes quite significant. The decrease in the value of the quality indices was manifested by the increase of the number of mistakes, either of the number of double planting holes (with at least two seeds), or of the number of missing planting holes. Both cases are unfavorable for the agricultural producer, generating production losses. This paper discusses the influence of the degree of soil grinding on sowing precision in operating conditions, by determining the spectrum of the vibrations induced in the mechanical structure of row units of a precision planter in contact with the soil of three different plots for three working speeds: 4, 6, and 8 km·h−1. Later, the vibrations were simulated under laboratory conditions, ...
In order to obtain a correct and always reproducible image of the performances achieved by a plan... more In order to obtain a correct and always reproducible image of the performances achieved by a planter (or any agricultural machine), laboratory tests are required, under specified conditions, well controlled, to determine the precision of sowing outside the optimal agricultural periods. The paper presents a theoretical model for estimating sowing precision (feed quality index) as a polynomial function of the second degree, dependent on seed norm per hectare, working speed, depression value, mass of 1000 seeds, as well as combinations thereof. REZUMAT Pentru a obține o imagine corectă și oricând reproductibilă a performanțelor atinse de o semănătoare de precizie (sau orice mașină agricolă) se cer inițiate încercări de laborator, în condiții dinainte precizate, bine controlate, pentru determinarea preciziei de semănat în afara perioadelor optime agricole. Lucrarea prezintă un model teoretic pentru estimarea preciziei de semănat (indicele de calitate al alimentării) ca o funcție polinom...
International Symposium ISB-INMATEH – Agricultural and Mechanical Engineering, 2018
In the past few decades, size and weight of agricultural machinery have increased significantly, ... more In the past few decades, size and weight of agricultural machinery have increased significantly, and as a consequence, the severity and depth to which the stress is transmitted into agricultural soil have increased. The objective of experimental determinations was to study the influence of some factors characteristics to compaction: tire inflation pressure, wheel load and contact pressure on the contact area between tire and soil, as well as 2D and 3D mapping of pressure distribution in the footprint. The front tire of the U445 Romanian agricultural tractor was tested at five tire inflation pressures: 100, 150, 200, 250 and 300 kPa, obtaining contact areas between 0.0252-0.0349 m 2 and contact pressures between 98-136 kPa. REZUMAT În ultimele decenii, mărimea și greutatea mașinilor agricole au crescut în mod semnificativ și, în consecință, au crescut severitatea și adâncimea la care se propagă tensiunile în solul agricol. Obiectivul determinărilor experimentale îl constituie studiul...
Precision for sowing is essential in order to achieve sowing quality works for hoeing plants, ult... more Precision for sowing is essential in order to achieve sowing quality works for hoeing plants, ultimately influencing the high productions obtaining. This paper presents a comparative study regarding the sowing accuracy obtained in laboratory conditions on a special stand, using 3 different row units: one individual transmission and two centralized transmissions for the seed distribution devices. The researches were developed for three working speeds, three different plant densities per hectare using corn as seed material.
This paper presents issues related to static testing of protective agricultural equipment structu... more This paper presents issues related to static testing of protective agricultural equipment structures and includes a description of the tested structure, the testing method, the testing conditions and the obtained testing results and those analyses. The protection structures along with the safety belt are designed to reduce the risk of injuring the operator in case of overthrow / rollover or accidental collisions of the agricultural equipment. The attempts for checking the mechanical strength of protective structures from agricultural operator machinery, are concerned with checking the protection degree that these structures assures the driver in case of overthrow / rollover or accidental collisions when operating or machinery is in transport mode.
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