13 research outputs found
Investigation of tractor engine power and economical working conditions utilization during transport operation
Article analyzes tractor working and its engine conditions from economical point of view. Overview of tractor wheel slippage reliance on the traction force and weight utilization coefficient is given. Tractor maximum driving force according to road and field conditions, and driving speed are submitted. Literature and theoretical investigation analysis is done, where interaction between tractor wheels made-up driving force and grip is analysed. Driving speed and driving force dependence on rolling resistance and total aggregate weight using nominal power is described. In the present experimental research reduction in fuel consumption of tractor transport aggregate by reducing engine speed and by keeping the same work speed, was determined
Tractor ballasting in field transport work
The article presents the investigation of the interaction of tractor traction force, mass, trailer and tractor mass ratio and wheel slippage. The analysis of the influence of ballast weight and wheel slippage on the fuel consumption under various field and road conditions was carried out. Wheel slippage dependence on the pull force, a weight force utilization coefficient and ratio of the mass of a trailer and tractor were stated and analyzed. The nomogram for operative selection of the optimal ballast weight and its location place is presented when instantaneous wheel slippage is known. The nomogram consists of three parts. In the lower part dependence d=f(mp/m), (wheel slippage on the ratio of the mass of a trailer and tractor) is placed. In the middle part there is dependence of the tractor mass m made of the expression of the wheel grip weight force utilization coefficient jg=Ft/G on the ratio of the mass of a trailer and tractor m=f(mp/m).The upper part is designed for dependence Dmp=f(mp)(transferred mass of tractor Dmp on the rear wheels on the mass trailer mp. The bottom part of the nomogram is connected with the middle part by the common abscissa axle on which the ratio of the mass of a trailer and tractor is placed. The curves of the middle part of the nomogram m=f(mp/m)are connected with the analogical concrete mass trailer values mp, placed in the abscissa axle by intermediate lines
Investigation of the interaction of wheel rolling resistance and pressure in tire
Dependence of wheel rolling resistance on different factors is analyzed in the article. Experimental results of tests and calculations of rolling resistance are given. The studies carried out according to the formed testing methods allow optimizing pressure in tires depending on rolling surface and vertical wheel loadsVytauto Didžiojo universitetasŽemės ūkio akademij
Analysis of main dynamic parameters of split power transmission
The review carried out had shown one basic approach of split power transmission to the organization of drive which is applied to stepless transmissions of tractors and parallel hybrid cars. In the split power transmission the power split device uses a planetary gear. Tractor engine power in the split power transmission is transmitted to the drive shaft via a mechanical and hydraulic path. The theoretical analysis of main parameters of the split power transmission of the tractor is presented. The angular velocity of sun and coronary gears of the differential set is estimated by solution of the system of equations in which one equation is made for planetary differential gear, and another – for hydrostatic drive. The analysis of the transmission gear-ratio dependencies on the ratio of hydraulic machines capacities is carried out. Dependence of the variation of angular velocity of the coronary and the sun gears on the ground speed of the tractor is presented. Dependence of sum shaft torque and its constituents, carried by mechanical and hydraulic lines, on sum shaft angular velocity and ground speed of tractor and engine speed is also presented
The interaction between pulling power and fuel consumption of the tractor during draft mode applications
Article analyzes tractors working and their engine conditions from economical point of view. Overviewed tractors wheel slippage reliance on the traction force and weight utilisation coefficient. Submitted tractor maximum driving force according road and field conditions, and driving speed. Done literature and theoretical investigations analysis, where analysed interaction of tractor wheel made-up driving force and grip. In presented experimental research where determined reduce of fuel consumption of tractor transport aggregate by reducing engine speed and be keeping a same working speedVytauto Didžiojo universitetasŽemės ūkio akademij
Environmental Impact Alternatives for Soil Tillage and Sowing: Farmer or Contractor?
In Italy, contractors provide agricultural farms with over 40% of the mechanization needs. Compared to farmers, they can more promptly amortize their investment and help reduce the environmental impact of mechanization due to the use of better performing machinery. The goal of this study is to evaluate whether the seedbed preparation and sowing operations carried out by contractors have a lower environmental impact than those performed by farmers. Data about 20 agro-mechanical contractor companies located in Northern Italy were collected investigating technical, operating and usage machines characteristics. Regarding farmers, a typical farm (50 ha, double cropping and fleet of 4 tractors) was considered as reference. Operation sequences carried out by contractors and farmers were identified and compared through Life Cycle Assessment to evaluate their potential environmental impact. The impact of seedbed preparation and sowing resulted generally lower when carried out by contractors. Compared to farmers, Climate Change was reduced by 24.5% for conventional tillage and 9.1% for minimum tillage. The greatest reductions in environmental impact are shown for Particulate Matter production and for acidification, mostly due to the emission reduction devices available on the modern tractors mostly used by contractors