The article concerns developing and implementing the technological principles for manufacturing the working bodies of chisel tools by casting grey cast iron with partial chilling of its working edges and surfaces interacting with the soil layer. High wear resistance of the working body is achieved by chilling its working part by means of a chill inserted into the mold, or by absence of coating in the corresponding zone of the mold. Severe overcooling of liquid cast iron contacting the chill or the metal surface of the mold causes crystallization of the meta-stable eutectics, and in the chilled part it acquires a ledeburite structure, the hardness being not lower than 64 HRC. At the same time, the bulk of the cast iron crystallizes in the stable system, forming austenitic-graphite eutectics and after complete cooling, it should have a pearlitic metal base, ensuring good machine ability of casting by cutting. Working surfaces and cutting edges of chisels are exposed to abrasive and chemical impacts of the soil, causing intense wear, the latter being the main reason for their failure. The utilization of the given technology will allow increasing service-life of the working bodies and improve the manufacturability, according to the criteria for labor intensity and casting mold making.

The study of transient modes of operation of the machine-tractor unit (MTU) in order to improve energy efficiency and energy saving is a very important task. The process of starting and accelerating of MTU is the heaviest mode of operation, which is characterized by considerable dynamic loads and which has a significant influence on the most important indicators: productivity, fuel efficiency, as well as slipping of propulsors, abrasion of the soil and tires, loading and lifetime of the elements of the transmission of tractors. One of the effective methods for reducing dynamic loading is the introduction of elastic-damping links in the drive of propulsors of tractors. The study of impact of elastic-damping drive of traction wheels on the parameters of the MTU operation during the acceleration period were carried out in a complex way: theoretically, on the six mass dynamic equivalent model developed by us, which adequately reflects the actual overclocking processes, and experimentally, in the field conditions on full-scale samples. Methods of software mathematical modeling and developed methods of experimental research were used. The complex of the conducted researches has established: due to the decrease in dynamic loads the improvement of all operational parameters of the MTA has been obtained, including: reduction in the slippage of propellers, tire wear and abrasion, a significant increase in energy efficiency: specific fuel consumption in the process of starting and accelerating of MTU with an elastically damping drive on stubble in gears from the third to the sixth decreases by an average of 40% compared to a rigid serial drive. Due to the smoothing of the peaks of the hook load (by 38%) and the torque (by 36%) with the elastic elements, a more smooth and at the same time more intensive acceleration of the unit is obtained (acceleration time is shortened due to the fact that the slippage is reduced and crankshaft speed is reduced in lesser degree).

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The question of increasing the wear resistance and resource of working elements for the development of soil through the use of sound technological methods of manufacturing them from inexpensive materials is considered. Increased tribological characteristics of the working elements are achieved by optimally structuring them into functional areas, depending on the perceived loads and peculiarities of the working conditions. According to the results of research, a promising material for the manufacture of chisel plows bits - gray cast iron is proposed. Gray cast iron SCh 20 with a bleached layer on the working surface with a thickness of about 2 mm has higher tribological characteristics as compared to rolled steel, as well as technological and economic advantages in production due to the use of casting technologies.

Tillage machines that have in their design elastic links in the fastening -f w-rking organs, under certain conditions, can generate active undamped -scillati-ns -f w-rking b-dies due t- the peculiarity -f the cutting pr-cess -f the s-il layer, which all-ws t- reduce the -verall level -f f-rce l-ading and the dynamism -f the functi-ning -f the entire system. At the same time, the questi-n -f the effect -f vibrati-ns -f the w-rking -rgan -n the agr-technical indices -f the -perati-n -f machine-tract-r aggregates, in particular -n the deviati-n -f the pr-cessing depth fr-m the mean value, bec-mes t-pical. The mathematical m-del describing dynamics -f m-vement -f the elastically fixed w-rking b-dy -f the cultivat-r machine-tract-r aggregates, taking int- acc-unt the f-rce, elastic and dissipative characteristics -f the links -f the system is c-nsidered in the article. Dissipative pr-perties -f s-il in the w-rk are characterized by the c-efficient -f attenuati-n -f the s-il envir-nment. The rigidity -f the elastic element in the attachment -f the w-rking member was determined fr-m the c-nditi-n that the frequency -f the natural -scillati-ns -f the system and the frequency -f the disturbing f-rce be equal, which c-rresp-nds t- a res-nant m-de -f -perati-n. Calculati-n -f this mathematical m-del all-wed t- determine the r--t-mean-square deviati-n -f the treatment depth and c-mpare its value with the value -f the devel-ped techn-l-gical t-lerance f-r the change in the rigidity -f the elastic element in the fastening -f the w-rking member, as a result -f which the f-ll-wing c-nclusi-ns were made: the use -f the self--scillati-n m-de -f the w-rking -rgans can significantly influence -n the stability -f the w-rking b-dy in the vertical plane, especially this affects the s-ils with weak dissipative pr-perties, It can be assumed that significant amplitude -scillati-ns -f the w-rking element in the h-riz-ntal plane can lead t- an increased abrasi-n -f the s-il backgr-und by the w-rking -rgan and, as a c-nsequence, t- an increase in the number -f er-ding particles in the s-il and the devel-pment -f wind er-si-n.