&lt;p&gt;The lever operated knapsack sprayers are most popular among the farmers in India. It delivers uneven flow with a highly variable droplet spectra and spray pattern. There are C.F. valves available in developed countries, which controls output pressure and the flow. Keeping in view these objectives, the present study has been conducted at Aspee Research Institute, Bhiwali, Dist. Thane. A constant flow of valve of 1.45 kg/cm2 pressure is tested with duro mist spray hollow cone nozzle and plastic hollow cone nozzle at different applied pressures for Knapsack Sprayer (LOK). For Knapsack Sprayer (with duro mist spray hollow cone nozzle and C.F valve of 1.45 kg/cm2 ) at 1.45 kg/cm2 applied pressures the nozzle discharge, cone angle, volumetric efficiency and uniformity coefficient are varied as 318 to 320 cm3/min., 76 to 77&amp;deg;, 85.50 to 86.00% and 1.93 to 2.0 respectively. In case of Knapsack Sprayer (with plastic hollow cone nozzle and C.F. valve of 1.45 kg/cm2 ) at 1.45 to 4kg/cm2 applied pressures the nozzle discharge, cone angle, volumetric efficiency and uniformity coefficient are varied as 329 to 335 cm3/min, 76 to 77&amp;deg;, 84.84 to 85.00% and 1.94 to 1.99 respectively.&lt;br /&gt;
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The valve pressure, discharge, cone angle, uniformity coefficient is found nearly constant (In both nozzles with C.F. valve) irrespective of applied pressures.&lt;/p&gt;
