A method for sensor operating-state determination of a valve arrangement to control a process medium flow through a pipeline having a valve element, arranged such that it can move axially within a valve housing via a pneumatic actuating drive by application of control pressure, with the control pressure being measured and evaluated in order to determine the sliding friction during the movement. The valve element can be moved at a constant speed over at least a subarea of the travel movement, the value of which speed is measured via a position sensor system for signal processing, with the currently applied control pressure being measured at approximately the same time for signal processing via a pressure sensor system. The current sliding friction of the valve element can be determined as a measure of wear state from both measured values, by an electronic evaluation unit, based on a proportional drive force expressed by the control pressure which occurs when the valve element is traveling at a constant speed.