Performance of Free Rolling and Powered Tillage Discs

This research study was done in the soil dynamics laboratory of Faculty of Agricultural Engineering, Kasetsart University, Kamphaengsaen Campus, Thailand, to understand the benefits of driven tillage disc by an external power compared to the conventional free rolling tillage disc under controlled experimental conditions. Performance of free rolling and power operated standard concave tillage disc was evaluated in the soil bin with a sandy loam soil (USDA classification). The setup consisted of soil bin system and measurement system. Double extended octagonal ring (DEOR) transducer and torque transducer with slip ring were used for forces and torque measurements. Different disc angles and disc speeds were considered for the study. Soil failure patterns of both discs were also studied. Driving disc by an external power found to be significantly affecting performance of tillage disc. Draft force of the disc observed at disc angles of 23o, 28o and 33o was reduced from 620 N, 860 N and 947 N to 188 N, 254 N and 360 N respectively when free rolling disc was replaced by powered disc. However it increased torque acting on disc driving shaft. Similar trend can be observed in other kinds of soils, however trend will be positioned up or down on Y-axis depending on respective soil strength properties. Moreover, powered disc provided continuous and smooth flow of furrow slice to the side. Consequently, powered disc was proved advantageous over free rolling disc in terms of smooth soil displacement, easy soil volume handling, better inversion of the furrow slice and reduced soil reactions. Moreover it provided better energy utilization.