Fuel consumption of some tractor models for ploughing operations in the sandy-loam soil of Nigeria at various speeds and ploughing depths

Abstract

Tractors acquired in Oyo State-Nigeria are primarily utilized for ploughing operations which represents the most costly single item in the budget of an arable farmer.  Tractor fuel consumption constitutes a significant parameter that affects tractors performances for ploughing operations.  The effect of ploughing speed and depth on tractors fuel consumption was therefore examined in a bid to establish their optimum operating conditions.  The soil characteristics of the study site were determined using laboratory tests.  Ploughing operations, using ASABE standard D497.5, were carried out on 100×500 m research farmland using Massey Ferguson (MF 435, 100 hp), Fiat (F130D, 100 hp) and Steyr(CVT170, 100 hp) tractors that were purchased in 2009.  Field experiments were conducted at 5.5, 6.5 and 7.5 km h^-1 ploughing speeds for ploughing depths of 20, 25 and 30 cm.  The soil type in the study site is predominantly sandy-loam.  Mean fuel consumption for Fiat, MF and Steyr models were 23.35, 23.58 and 24.55 L ha^-1 while average of 16.78, 22.02 and 32.67 L ha^-1 of diesel were used to plough 20, 25 and 30 cm depths respectively.  Fuel consumption values increases with ploughing dept significantly, there is 31% increase from 20 to 25 cm and 48% increase from 25 to 30 cm depths.  Mean fuel consumption at 5.5, 6.5 and 7.5 km h^-1 ploughing speeds were 20.0, 24.25 and 27.23 L ha^-1 respectively.  Fuel consumption increased by 4.25 L (21%) when speed is increased from 5.5 to 6.5 km h^-1 and 2.98 L (12%) when speed increases from 6.5 to 7.5 km h^-1.  Mean fuel consumption (23.35, 23.58, 24.55) L ha^-1 for MF, Fiat and Steyr tractors respectively were significantly different at the various speeds and ploughing depths (p<0.05, 0.87 ≤ r² ≤ 0.99).  The most appropriate combination of ploughing operating parameters in terms of tractor fuel economy is achieved using Fiat tractors at 6.5 km h^-1 ploughing speed and 25 cm ploughing depth.  Tractors’ performance for ploughing operation depends significantly on ploughing speed, ploughing depth and tractor type.  However, the depth of crop roots should determine the appropriate ploughing depth in order to minimize expenses on fuel.

Keywords: tractor performance, soil types, ploughing depth, ploughing speed, fuel consumption