Effect of Different Working and Tool Parameters on Performance of Several Types of Cultivators

In this study, the effects of tillage depth, forward speed and soil moisture content during the cultivator operation on the draft force, energy requirement, and soil disturbance were investigated using five types of cultivators. The experiments were performed in the factorial design based on the randomized complete block design (RCBD) with three replications in loamy sand soil. Different soil moisture contents (factor A) from 5 to 16% for dry soils and 17 to 35% for wet soils, forward speed of tractor (factor B) at four levels of 1.16, 1.61, 1.97, and 3.82 km/hand working depth (factor C) at two levels of 10 and 20 cm were selected. The analysis of variance results showed that the main effects on the draft force, energy requirement, and soil disturbance were significant. With increasing the forward speed, working depth, and blade width, the draft force, energy requirement, and soil disturbance significantly increased. As the soil moisture content increased, the amount of draft force decreased. The average maximum draft force and energy requirement are related to the crescent cultivator and the lowest ones to the cultivator with a sweep blade. The maximum amounts of draft force and energy requirement at the speed of 3.82 km/h were 296.702 N and 0.03708 MJ in the dry conditions, respectively. The average maximum draft force and energy requirement are related to the crescent cultivator and the lowest ones to the cultivator with a sweep blade. The average maximum draft force and energy requirement in dry soil at 10–20 cm depth were 313.534 N and 0.039204 MJ, respectively, and the lowest values were 189 N and 0.019512 MJ in wet soil at the depth of 0–10 cm, respectively. The highest mean value of the area obtained from the profiles was 254.62 cm2 related to the dry conditions and forward speed of 3.82 km/h, and the lowest mean value of the area obtained in the wet conditions was 199.6 cm2 at the forward speed of 1.16 km/h. The highest average area obtained from the profiles was observed in the dry conditions for C4 as 434.813 cm2 and the lowest one was 57.94 cm2 in the wet conditions for the cultivator with a chisel blade and L-shaped shank. The highest average area created by cultivators at the 10–20 cm depth in the dry conditions was 332.875 cm2 and the lowest one at the 0–10 cm depth in the wet conditions was 123.55 cm2. The results of this study can help the designers and manufacturers of agricultural machinery to effectively design and manufacture the machinery with optimum draft and energy requirements.