Demelash Lemi G., Kishor Kolhe P. and Siraj Busse K.
Abstract
The Government of Ethiopia is trying to improve sugar industry sector by establishing new factories,expansion projects and rehabilitation of existing ones. The main input in this process is agriculturalmechanization; however it has been resulted in a huge number of farm machinery of various types andsizes, without consideration of proper selection and matching between tractors and their attachments(implements). This approach had led to high cost of agricultural operation, resulted in an unbalanceddistribution of machinery and the agricultural operations throughout the years. Wonji Shoa Sugar factoryis one of the victims of the aforementioned problem. The present study was conducted to evaluate thecurrent farm machinery selection practices of Wonji Shoa Sugar Factory. Three soil types namely; heavyclay, vertisol and sandy loam were selected with four field activities (subsoiling, ploughing, harrowingand furrowing). For subsoiling, ploughing and harrowing, 9410-R John Deer tractor with implements of 5shank and 3.2 m wide mounted subsoiler, 2.8 m wide double gang offset disc plough, and 3.5 m wide semimounted four gangs double offset were used respectively. For furrowing YTO-1804 tractor and a fourbottom fully mounted 4.5 m wide rider was used. For each experiment, the draft force requirement of theimplements, the drawbar power, fuel consumption, overall energy efficiency and power utilization ratiowere determined at different tractor travel speeds. Subsoiling, ploughing and harrowing were activitieswere evaluated at the travel speed of w 3, 4, 5 and 6 km/hr. And a travel speed of 4, 5, 6 and 7 km/hr wereused for furrowing operation. Linear regression tests were run to examine the interactions between thefactors and determine their significant impact. The results of this study noted for furrowing operation aslowest draft force, drawbar power, fuel consumption and energy efficiency of 14 kN, 12.65kW, 13 lit/hrand 8.7 % respectively in sandy loam soil type. The maximum Draft force of 79.8 kW and drawbar power of131 kW was noted for subsoiling operation in Heavy clay soil. Moreover the results of all operation in allsoil type, as indicated by both overall energy efficiency and power utilization factor shows the mismatchbetween the tractor and implements, as the tractors were overpowered. That means a less amount of theavailable power from the tractor is being used to operate the implement. If the tractor had been matchedwith a bigger and compatible implement a better efficiency and higher productivity of the tractor implementcombination could have been achieved.