Abstract:
Three active tillage implements; rotavator, power harrow and spading
machine were tested in three fields at various engine speeds in order to study the
tilth produced by these implements. It was observed that the suitability of an
implement was changed according to the soil properties considered. Power harrow
and spading machine can be recommended for getting lower bulk density,
whereas rotavator and power harrow were suitable for higher soil pulverization
and soil inversion. The deeper operating depth can be achieved by the usage of
spading machine. Rotavator consumed less fuel and lower operating cost per unit
area.
The soil tilths obtained by these implements were compared using value of
tillage performance index and ranking by grey relational analysis. In both the
cases rotavator was found to be better compared to others. The cost of operation,
energy requirements and time of operation of the tillage implements showed that
lower values of Rs. 3300, 827.91 MJ and 3.03 hours per hectare were observed in
operation of rotavator followed by power harrow, Rs. 4500, 1029.68 MJ and 4.76
hours, and higher values of Rs. 7900, 1686.10 MJ, 9.09 hours were found in
spading machine respectively.
The implements were operated in multiple passes on the same field to study
the variations in tillage quality. Two pass of rotavator, two pass of power harrow
and three pass operation of spading machine were found to be similar based on the
soil properties. The respective ratios of cost, energy and time expenditure were
obtained as 1 : 1.33 : 2.93, 1 : 1.42 : 3.43 and 1 : 1.18 : 2.41 for rotavator, power
harrow and spading machine. While considering in the point of view of grey
relational ranking and tillage performance index, rotavator operation was found
best. The cost and energy analysis of the operations also have computed. It also
indicated rotavator has the best results. The spading machine can be used for
fields which need higher operating depth, even though it’s operating cost and time
of operation were higher.
