Field Studies of Disc Harrow-Cultivator "Dukat-4" with Discs Mounting Rack of Different Rigidity

Abstract

The article presents the results of operation research of harrow-cultivator "Dukat-4" produced by Lozovsky forging - mechanical plant with discs mounting rack of different rigidity: maximum (No. 1), medium (No. 2) and minimal (No. 3). The degree of rigidity was provided by the design of each of the three types of racks. The aim of the research is to determine the effect of rack stiffness on the quality of the operation of "Dukat-4", as well as traction and power performance of a tractor unit as a part of the "Dukat-4" and wheeled tractor T-150K-09. The quality of the operation was determined by the magnitude of the indicators of the depth and uniformity of processing, ridgeness and the degree of weed control. The estimation of operational indicators, as well as traction-energy indicators was carried out on two backgrounds: a field after harvesting of sunflower (background 1), and a stubble field after harvesting of barley (background 2). The estimation of quality indicators was carried out according to standard methods [5 - 8], as well as private methods. Traction-energy indicators were determined using the measuring system developed at the Department "Tractors and cars". Each of the backgrounds was characterized by soil moisture, which was at the range of 11.0 -17.4 percent, the hardness of which on the background 1 was in the range 2.25 - 4.13 MPa. The estimation of quality indicators, showed the advantage of racks of medium hardness (No. 2) as for the uniformity of depth of processing, which was proved by the coefficient of variation – 36,2% as compared to racks 1 and 3 (45,3 - 40,0%). Rack No. 2 provided the minimum ridgeness, and the highest degree of destruction of weeds – 95%, 86,5 and 92.7 for racks No. 1 and No. 3. Traction and dynamic performance of "Dukat-4" with racks of different rigidity also showed the advantage of racks No. 2 on the both backgrounds: traction resistance was the lowest with 5.0% against 6,5 - 8,5% (background 1) for racks No. 1 and 7,0 - 9,0% for racks No. 3.