Website Exclusive: The power of flood prevention
Colombia’s Guadalupe IV hydroelectric plant has solved its flooding problem and saved thousands of dollars with a specialised automatic control valve.
The Colombian State of Antioquia creates much of its clean power from hydro plants along the Guadalupe River. In the case of the Guadalupe IV hydroelectric plant, the risk of flooding required a suitable solution to ensure that the ejector pumps would work regardless of power or pressure differentials.
The engineering team looked at installing automatic control valves. The original project was designed with a plunger valve, but this was not a good option as the pressure drop across the valve would cause cavitation. In control valves, the pressure drop typically occurs at or near the seat area or just downstream. The shock waves and pressure fluctuations resulting from these high velocity bubble collapses can also cause noise, vibrations and accelerated corrosion, as well as limited valve flow. Typically, the cavitation is formed in the valve throttling area and the pressure fluctuations radiate into the downstream pipe as noise. As the cavitation increases the magnitude of these pressure fluctuations also increases.
After careful consideration the engineering team chose to go with Singer’s 8 inch Pressure Reducing Control Valve with Anti-Cavitation trim.
Singer’s 8 inch Pressure Reducing Control Valve comes with Single Rolling Diaphragm Technology that provides smooth, steady and precise pressure control from maximum to virtually zero flow. The effective area of a single rolling diaphragm remains constant so the bonnet is much smaller and lighter than a flat diaphragm version. A measured quantity into the bonnet control chamber always gives the same smooth movement of the inner valve through the entire stroke. A smaller bonnet also makes the valve lighter and safer for maintenance, while the smaller control chamber enables it to respond faster to changing pressures. By eliminating the seat chatter at low flows, the SRD avoids injecting small pressure pulses into the piping which, over time, may increase leakage, losses or pipe bursts.
To learn more about how Guadalupe IV solved their flooding problems and saved thousands of dollars, read the rest of Singer Valve’s exclusive case study on pages 47 and 48 of the online edition of Fluid Handling, here