Friction analysis and modelling of a novel stepped rotary flow control valve


High flow rate control is very important for different applications ranging from constructional, industrial, military and aerospace. Generally, hydraulic control relies on different types of valves. For example, poppet and spool valves have been implemented in Independent Metering (IM) system which is usually installed in mobile hydraulic machines such as excavators. Recently, a novel rotary flow control orifice has been developed to design a control valve for high flow rate applications, and a stepper motor was selected as the main actuator for this orifice to grant more accuracy and controllability. The coupling between these two main components requires analysis of the internal dynamical interactions and their effect on the performance. Friction torque is an important parameter to be considered in this design. The paper includes analysis and modelling of the friction torque in the orifice which affects the coupling, also it contains a model validation and evaluation resulted from friction practical measurements.