VACUUM PRESSURE DEVICE AS AFFECTED BY SUCTION TUBE CHARACTERISTICS

There are numerous types and sizes of air seeders and planters, some of the designs and concepts used for vacuum air are recognized. planting using vacuum air systems faces multiple problems. one of the most important is optimum vacuum pressure through delivery air tube from outlet gate of vacuum pump to grain picking orifices at circumference of feeding disc. from this standpoint this research aims to identify the lowest vacuum levels that recognized best captures of corn grains. to perform this study, a similar model of six rows vacuum planter with six delivery tube lines different in length was constructed in farm machinery laboratory research (ismail, 2004) as part of outcomes from a project financed by researching unit of mansoura university. the response surface program of minitab 17 was used to identify relationship between vacuum pressure (kpa) and each of blower speed (fns, rpm), vacuum measuring location far from outlet of blower orifice lvt and three different of air delivery tube length tl. the maximum vacuum pressure (4.19 kpa) was recorded at blower speed of 657.6 rpm at distance from the blower outlet orifice lvt of 0.27m. also, it can be stated that, increasing the lvt distance from the blower outlet orifice, or decreasing the fns speed lead to demolish the vpm values. moreover, the effect of height of fns parameter was more than that the effect of lvt parameter. also by increasing the location of measuring points far from outlet blower the vpm decreased under all different variables. the decreasing rates were found about 0.75; 0.77 and 0.68 times as increasing lvt from 0.14- 1.5m; from 0.28-2.0m and from 0.27 to 3.0m respectively at blower speed of 310.4rpm.