Calibration and Performance of Tractor Mounted Rotary Fertilizer Spreader

The study aimed to test tractor mounted rotary disc fertilizer spreader with two ground speeds in order to obtain higher field capacity with required spreading uniformity. The spreader was calibrated at a rate of 250 Kg Urea ha-1. Spreader was calibrated by using weighed amount of fertilizer in hopper and re-weighing remaining amount after running spreader over test strip of known area. Spreader was tested over area of 1000 m2 for its performance at two different ground speeds. At 4.23 km hr-1ground speed, with fertilizer application rate of 250 kg ha-1, effective field capacity was 2.78 ha hr-1 with field efficiency of 71.28%, fuel consumption of 1.11 Liters ha-1 and CV of fertilizer samples was 20.82%.While at 8 km hr-1ground speed with fertilizer rate of 250 kg ha-1 field capacity was measured as 5.33 ha hr-1with field efficiency 73.11% and a fuel consumption of 1.64 Liters ha-1 with 21.73% CV of fertilizer samples. Data were analyzed using Gnumeric 1.12 software .Aspect ratio of fertilizer samples revealed almost same quantity of fertilizer spread on left and right from the center of swath. This study concludes that there is no significant effect of ground speed on spreading uniformity of rotary disc spreaders. Spreaders should be operated at higher ground speeds to achieve higher field capacities.