No abstract

he paper presents an analysis of the basic principles of formation, the properties and characteristics of a new modular energy tool, consisting of the energy and the technology modules. The purpose of this study is to assess the degree of impact of the throttle in the hydraulic line, connecting the cavity of the hydraulic cylinder, upon the controllability of the modular power tool with a mounted plough during the movement of the ploughing aggregate on the headland. As a result of the conducted tests, it was proved that increasing the controllability of the movement of the aggregate on the basis of a mobile power tool is possible by throttling one of the hydraulic cylinders that limit the mutual reciprocal rotation of the modules in a horizontal plane. Installation of the throttle modular power tool on the limiting hydraulic cylinder with a drag coefficient 1.03×106∙N∙m∙s∙rad–1 allows one to reduce two times the delay in the reaction of the relative bearing of the energy module to a change in the angle of rotation of its driven wheels.

The article presents research results of a machine-tractor unit that performs two technological operations simultaneously: (i) chopping plant residues (sunflower stubble); (ii) covering the chopped stubble with the soil. The first operation is carried out with a front-mounted plant residues chopper, and the second one is carried out with a rear-mounted plough. The chopper’s working devices are rotated by the tractor’s front power take-off (PTO), which has two operating modes: 540 and 1000 rpm. It was determined that to reduce the dynamic load in the drive of the chopper’s plant residues working devices, to chop these residues qualitatively, and then to cover them with the soil, the tractor’s front PTO should be adjusted to a speed of 1000 rpm. With this mode of the chopper’s working device’s rotation, the difference in its vertical vibrations’ dispersion and the tractor front axle’s oscillations is insignificant. The variance of the plowing depth vibrations (1.44 cm2), changing aperiodically in the frequency range of 0–2.5 Hz, is not accidentally less than the variance of irregularities vibrations of the longitudinal field profile (2.75 cm2). The plough draft resistant oscillations of the plow-chopping unit had the least impaction at the plowing depth oscillations. The proof of this is the small value of the cross correlation function; for such oscillating processes as ‘plough draft resistance—plowing depth’, it was equal to 0.22, which is 3.4 times less than for oscillating processes ‘surface’s longitudinal profile—plowing depth’. The number of chopped particles less than 15 cm in length increased by 1.5 times, and the number of particles longer than 30 cm decreased by 3 times. With the complete incorporation of plant residues into the soil, their non-chopped part did not exceed 1%.

The versatility of tractors can be increased by using them as a part of a modular draft device (MDD). MDD consists of energetic (EM) and technological (TM) modules. EM is a high-energy tractor with a 2WD or 4WD wheel arrangement and a traction force of 14-16 kN. TM is an additional axle with an active drive of its wheels. By connecting TM to the rear hitch linkage (RHL) of EM, the tractive effort of the entire MDD, which has a 4WD or 6WD wheel arrangement, increases to 32-36 kN. MDD can function as a road-rail vehicle. Depending on the traction resistance, MDD can be used both as part of an EM+TM or as a single EM. According to the research results, it was found that the maximum traction efficiency (TE) of MDD with a 6WD wheel arrangement is about 10% higher than that of MDD with a 4WD wheel arrangement. The TE value of MDD increases with an increase in the inclination of EM rear hitch linkage top link. The increase in MDD’s tractive efficiency is facilitated by an increase in the coefficient of kinematic discrepancy in the drive of the EM and TM wheels from 1.00 to 1.05.

This paper is dedicated to Tekrone composite material utilization in agricultural machinery. In terms of its technical properties, tekrone is very similar to steel 60 that is used for production of plough mouldboards and landsides. However, Tekrone shows more preferable characteristics, because its friction coefficient (kf) is 2.6 times lower in contrast to steel 60. This fact indicates that the draft resistance can be decreased by replacing the plough mouldboards and landsides made of steel 60 with their counterparts made of Tekrone. This science hypothesis was confirmed by experimental investigation results. Analyses showed that utilization of plough with Tekrone mouldboards and landsides instead of steel ones significantly reduces their sticking to the wet soil. This results in a “soil moves over plough mouldboard surface” process instead of a “soil moves over soil” process. The plough draft resistance was decreased by 13.6% after replacement of the steel equipment with Tekrone one. Simultaneously, the performance of new tractor-plough aggregate was increased by 12.6%, the specific fuel consumption was reduced by 11.8%, and the preserving probability of the agrotechnological ploughing depth tolerance (±2 cm) was increased from 88% to 93%.