Repeatable test of a control valve with air pressure generated by an independent electric energy source

Water resource management is an important issue in a region where water resources are far from residential areas. Pipelines can provide a water connection between water resources and residential areas. Control valves are useful in controlling the supply of water based on a time table, faciliting effective manangement of the amount of water supplied. A control valve system with an independent electric energy source (CVS-IEES) can minimize maintenance costs in desert or jungle areas, where maintenance by human efforts may be insufficient. This study suggests that two types of tests, namely, repeatability and flow coefficient tests, can provide the impetus for designing the CVS-IEES. The repeatability test measures the number of repeatable operations of opening and closing an on/off valve. Test result showed that a fluid volume of 15 L at a pressure difference of 5 bar (gage) was feasible for operating a pneumatic on/off valve with a pipe size of 200 mm within 1 s, and the torque must be 7500 N·m. The flow coefficient test result was a function of the valve opening ratio (or aperture rate). The flow coefficient of a control valve with a pipe size of 50 mm was K_v = (2.48 ± 0.20) m³/bar^0.5·h at q = 3.94 m³/h. The measurement uncertainty of 0.20 m³/bar^0.5·h enables the CVS-IEES designers to estimate the accuracy when controlling the amount of supplied water.