Linearisation of control valve characteristics

There are a variety of valve types with different advantages and disadvantages for process control. Angle seat valves are cost-efficient and have a high flow capacity. Diaphragm valves are hygienic and minimise dead space. However, the S-shaped valve characteristic of both types means that the desired gain is only achieved in a relatively small stroke range. Their use is therefore limited. This white paper describes possibilities for linearising S-shaped valve characteristics in order to achieve a characteristic curve that is as linear as possible. This allows the control range of diaphragm and angle seat valves to be increased and process control to be significantly accelerated.