VALVES AND FLOW CONTROL A FLEXIBLE SOLUTION
DRALLIM
Drallim Rotary Selector Valve ( RSV ) is a flexible solution for process control
The Rotary Selector Valve or RSV is a multiport , sprung loaded poppet valve , driven by a stainless steel profiled internal cam ( spindle ), with each port configurable in multiple banks . It stacks allowing different fluids to pass through each bank , in a variety of sequences , with indexing , key locks , actuation , switch outputs and a host of other options .
Used in small bore piping systems in the range -1bar to 10bar it is a simple and extremely reliable unit , of modular design , configurable for a multitude of applications . Available in both brass and stainless steel , with stem and seal materials chosen to suit the process media .
In complex pneumatic control systems for high integrity applications , it eliminates the cross-port leakage issues found with multiport ball valves . Also used in hydraulic applications such as drain and purge , or hydraulic actuation and many other control applications , where process sequences and interlocking can be easily configured in one device , providing a highly adaptable solution to a wide range of fluid control applications .
When being used in processing plants , where the flow is controlled by inline valves , pneumatic control of the actuators that open or close is achieved using electrical solenoid valves , that , in turn , pressurise or vent the actuators . As an emergency safety feature or to carry out planned maintenance , it is necessary to by-pass those solenoids and using an RSV enables a manual override .
In complex pneumatic control systems for high integrity applications , it eliminates the cross-port leakage issues found with multiport ball valves .
Single acting actuators ( spring return ) are controlled by a single pneumatic signal and are bypassed using a single bank RSV , having one airpath .
Double acting valves require one side to be pressurised with the other vented , employ a two-bank .
Multiple actuators can be controlled by a single RSV , the series 40 having up to eight separate banks .
For further information , please visit www . drallim . com
156 PECM Issue 58