Service Contract No 2007 / 147-446 - Swaziland
Service Contract No 2007 / 147-446 - Swaziland
Service Contract No 2007 / 147-446 - Swaziland
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5.1.2 S p r i n k l e r p r e s s u r eThe optimal operating pressure (kPa) of the sprinkler should be between 60 and 70 times thenozzle diameter (mm). This is applicable to nozzles of 3 to 7 mm diameter (ARC, 2006).Table 2. Optimal Operating Pressure Vs <strong>No</strong>zzle Diameter for Sprinklers<strong>No</strong>zzle diameterOperating pressure (kPa)Mm inches x 60 x 701,591 / 16 "1,985 / 64 "2,383 / 32 "2,787 / 64 "3,181 / 8 " 191 2223,579 / 64 " 214 2503,975 / 32 " 238 2784,374,765,165,565,956,3511 / 64 " 262 3063 / 16 " 286 33313 / 64 " 310 36115 / 64 " 333 38915 / 64 " 357 4271 / 4 " 381 445Pressure at sprinklers was measured with a pressure gauge, fitted with a pitot tube (Figure17). The point of the pitot tube was held about 2 mm in front of the nozzle opening in the pathof the jet of water to measure the “vena contracta”. Therefore, the velocity pressure, whichindicates the pressure head and is equivalent to the total pressure, was measured.Maphobeni Farmers Association Report - 2009 Page - 35 -