conjunto de válvula de controle, método para determinar um modo de falha em um conjunto de válvula de controle, e, posicionador para um conjunto de válvula de controle

摘要

A control valve assembly is capable of diagnosing malfunctions in the control valve assembly and discerning a location of a control fluid leak in the control valve assembly. The control valve assembly includes a control valve, an actuator and a positioner. The actuator includes an actuator vent in an actuator housing, the actuator vent being connected to a flow switch. By determining a flow condition through the actuator vent, the positioner determines whether a control fluid leak is located in a control line or in a diaphragm.