New Working Organs for Solid Tillage of Fallow Fields in Summer Season

. The work is of an applied nature and is aimed at substantiating the need to develop the working bodies of the tool for processing steam fields in the summer to preserve moisture in the soil, the main technologies for processing steam are given, the working bodies of steam cultivators are grouped, the design of a new working body is proposed, consisting of 2 narrow one-sided paws, its description is given, the angles of setting the upper part of the working body in the transverse and longitudinal-vertical planes and the horizon are justified, in conclusion, the results of the work done are given.


Justification of the need to develop the working bodies of the tool for fallow fields tillage in summer season
Guaranteed high yields of winter crops, including winter wheat in conditions of lack of moisture, which is typical for the southern steppe zone of Russia, can be obtained only on fallow fields (in Rostov region in 2020 -39 thousand hectares of fallow land, 16.1% of arable land). In this regard, the tillage of fallow fields is the most important stage in obtaining high-quality food grain, especially in the summer and before sowing [1,2].
Depending on soil and climatic conditions in the steppe zone of the North Caucasus, at least four main technologies of fallow tillage are used, which differ both in the method of main tillage (tilling and non-tilling) and in the time of its implementation (black, if the main tillage is carried out in the fall, and early, if the main tillage is carried out in the spring in the year of winter sowing) [3,4].
Famous Don scientists -farmers N. N. Borodin, I. G. Kalinenko in their works emphasize the need and importance of a layer by layer tillage of fallow fields from a great depth (14 -18 cm) with a gradual decrease to 5-6 cm, so they approached the sowing time of winter crops.
They also consider "... unacceptable to till fallow fields in the second half of summer deeper than 8 cm".
To ensure the depth of fallow fields tillage of 4-6 cm in the summer without removal of wet layers to the daytime surface by the present tillage machines and tools equipped with working bodies, usually in the form of pointed grips, is almost impossible. At the same 2 time, the upper soil horizon is eventually dried up and the conditions for subsequent seed sowing in moist soil are not provided.
Currently, the proposed working bodies of tillers for continuous tillage (field tillers), which are conditionally referred to moisture-saving, can be divided in following groups (Table 1). However, the analysis of presented structures and the available data of their comparative agrotechnological assessment shows that some of the working bodies used make a significant amount of wet layers on daytime surface, the other part does not provide a stable soil tillage depth (4-6 cm) or does not destroy weeds during tillage [5,6,7,8]. In this regard, we propose the design of a new working body consisting of 2 narrow one-sided grips mounted on a holder, together with a chisel-shaped cutter (Figure 1). Such a combined working body can be installed either individually on the frame of the field cultivator, or several pieces on an additional frame with a chain suspension. The main element of the proposed combined working body for field cultivators is a one-sided standfree grip (right or left), which provides soil loosening to the required depth, including the minimum (4-6 cm), 100% cutting of weeds and the removal of wet layers to the daytime surface. In addition to this, a "stub", which provides for compaction and mulching of the surface soil layer, is proposed ( Figure 2). а) 1rack; 2, 3pad; 4bracket; 5slat; 6spring; 7gearing; 8, 9screws; 10stand; 11chisel; 12holder; 13, 14grip b) 1chisel; 2 stand; 3right sidewall of a holder; 4left sidewall of a holder; 5left unilateral arm; 6right unilateral arm where В 1width of strips tilled by the proposed working body (B1=90 mm);

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where llength of cutting ridge of an upper bend from its upper end. Under R max l=23 mm (under R min l=29 mm); l dactual length of a cutting edge of a working body from a lower inflection line to its end (l d =179 mm) Figure 3b.

Justification of angles () and () of setting the upper part of the working body in transverse and longitudinally vertical planes and the horizon.
The main purpose of the technological technique performed by the unit with the proposed working bodies is to create a tilled layer with a thickness of h=55-60 mm.
To determine the minimum and maximum angles  and  (Figure 1 a, g), we use the expression: where hthickness of the tilled layer, h min =55 mm;h max =60 mm; l вlength of the upper part of the cutting edge of the working body, l в =89 mm.
So, the upper part of the working body in the longitudinal-vertical plane should be set at the angle to the horizon within 38 0 <<42 0 , and the angle of setting the upper part of the working body to the horizon in the transverse-vertical plane should be within 38 0 <<42 0 .

Justification of the angle () of setting the lower part of the working body to the horizon.
To determine the maximum and minimum values of the angle (), we use the expression: where angle between Rкhorizontal component (Figure 1g) and Rresulting component of all forces acting to the lower part of the working body; angle of the soil friction to steel 31 0 -42 0 .
So, the lower part of the working body must be set to the horizon at the angle 15 0 <<18 0 . The ratio of the radius (R) of the interface of the upper and lower parts of the working body to the width of the working body (B) is obtained from the expression; where В = lsin =189 mm; 0,2<R/B<0,3, angle of the setting the working body to the line of motion 42 0 ; The general length of the cutting edge of the working body: where l-general length of the cutting edge of the working body; l Н = В/sinlength of the cutting edge of the lower part of the working body; l Н = В/sin= 134 mm. l П =В П / sin= 39,5/sin42 = 59 mmlength of the cutting edge of the working body necessary to overlapping. l В = h/ sin= 60/sin42 = 89 mmlength of the cutting edge of the working body. To check the obtained length of the working body for the possibility of the soil unloading in front of the working body, we use the dependence for it [9]: where angle of crumbling,  = 15 0 -28 0 ;  1angle of the soil friction to steel,  1 = 31 0 -42 0 ;  Сtemporal soil resistance to compression,  С = 650 g/cm 2 ;  обsoil volume weight,  об = 2,4-2,7 g/cm 3 ; Vvelocity of movement, V = 2,4-4,1 m/s; gacceleration of free falling; l 283, that is 282 283, and it indicates to the exclusion of soil unloading in front of the working body at selected parameters and speeds of movement. The relation of maximum (R max = 53,95 mm) and minimum (R min = 39 mm) radii of the interface of the lower and upper parts of the working body to the gripping width will be equal: R max / В= 53,95 / 189 = 0,30 R min / В = 39 / 189 = 0,20.
So, the ratio of the radius of the interfaces of the upper and lower parts of the working body to the gripping width must be within 0,2<(R/B)<0,3.

Conclusion
Based on the analysis of the design and technological schemes and parameters of existing working bodies, the compliance of their agrotechnological performance indicators with the requirements to work at depths of 4-6 cm without transfer of wet layers to the daytime surface, the technological task (project) was developed for the design of the combined working body, connecting elements, and a rolling-up device, there were made the model samples of new working bodies, and the preliminary field studies were conducted.