Design, Development and Evaluation of Tractor operated automatic gun sprayer for field crops

Abstract

The tractor operated automatic gun sprayer was designed and developed by considering crop and machine parameters. The tractor operated automatic gun sprayer was evaluated under the laboratory to ascertain the performance under different variables. Its performance was evaluated in the Department of Farm Machinery and Power Engineering, plant protection laboratory, College of Agricultural Engineering, University of Agricultural Sciences, Raichur during 2016-17 under the controlled conditions to eliminate the effects caused by environmental parameters. The laboratory experiments were carried out by using the actual cotton plant. the developed sprayer was evaluated under three different nozzle size, operating pressure and orientation of spray nozzle The nozzle discharged increased by 38.23 per cent as the operating pressure increased from 20 to 24 kg-cm- 2 for 2 mm nozzle size and discharged increased by 31.70 per cent when the nozzle size changed from 2 to 6 mm at operating pressure of 20 kg cm-2. The droplet density increased with an increase in the nozzle size. The droplet density was increased by 38.09 per cent when the nozzle size was changed from 2 to 6 mm. The droplet deposition on both upper and lower surface of the plant canopy was maximum when the orientation of the nozzle was 15 degree. The performance evaluation of tractor operated automatic gun sprayer was carried out in cotton (Bt) at the farmers' field and Research Farm, Raichur. An anemometer was used to measure the wind velocity over the target crop. A Thermo hygrometer was used to measure the temperature and humidity. Methylene blue MS dye mixed at5 g l -1 in water was sprayed on cotton crop and pigeon pea. The droplet density was decreased by 13 per cent as the height of the spray nozzle was increased from 30 to 90 cm for 64 cycles min-1 speed of the actuating mechanism. The droplet size decreased by 10.65 per cent as the forwarding speed of the tractor increased from 2.2 to 2.6 km h-1 for 30 cm height of the spray nozzle. The cost of operation of the developed tractor operated automatic gun sprayer was found to be Rs. 320.06 ha-1 and Rs. 302.7 ha-1 for cotton crop and pigeon pea crop.