Test bench for measuring the actuation of large valves
Nowadays, valves of large nominal sizes are usually actuated by means of hydraulic pilot control. This is characterized by an excellent power density and high achievable forces. However, due to the increasing power density of electromechanical actuators, they are increasingly becoming an alternative to hydraulic pilot control. The aim of the research project "Electromechanical actuation of large switching valves" was to analyze the advantages and disadvantages of different electromechanical actuators for the actuation of large switching valves.
Determination of the requirementsCopyright: © ifas
The test bench serves for determining the requirements for an electromechanical actuator for valves of large nominal sizes.
On the one hand, the test bench allows the detailed investigation of the hydraulic pilot control process with regard to the switching time, the pilot control stage's current demand, as well as the pressure built up in the pilot control chambers. On the other hand, it is also possible to measure the forces (flow and friction forces) acting on the valve spool as a function of position, by means of a specially designed electro-mechanical control system. For this purpose, the test rig is equipped with pressure sensors, temperature sensors and a flow rate sensor. The pressure difference at the test valve can be adjusted by means of a pressure relief valve. The test stand is designed for volume flows of up to 600 l/min and pressures of up to 320 bar.
Electromechanical ActuatorCopyright: © ifas
Furthermore, the test bench is designed to investigate three constructed electromechanical actuators for the control of valves of nominal size 25. On the test bench, it was possible to provide a proof of function for each of the three actuators for different operating scenarios and to gain further knowledge about their operation conditions.
The performance of the electromechanical actuators in terms of actuating time, reset time and energy consumption was compared with the performance of the hydraulic pilot control.Copyright: © ifas