A fieldbus solenoid valve system has a solenoid operated control valve mounted and operated by a solenoid pilot. A direct current power source is connected to a coil of the solenoid pilot and a driver for actuating the coil. A resistive element is in series with the power source, the driver, the solenoid and a ground. A frequency generator is connected to the circuit for creating a frequency pulse train to the coil having a characterization so as not to cause the solenoid pilot to actuate. The voltage is measured between the coil and resistive element and the measured voltage is compared to a base voltage value measured from the same circuit location. An indicator signal is displayed on the fieldbus solenoid valve system or externally when the measured voltage increases to a predetermined amount from said base voltage over time.

A system and method include measuring input electric current that is input into an electrically controlled valve to change a position of the valve. Output electric current that is output from the valve in response to the input electric current being input into the electrically controlled valve is measured. Position signals are generated using a sensor coupled with the electrically controlled valve that are indicative of the position of the valve. Baseline values associated with the input electric current, the output electric current, and the position signals are calculated. A health state of the valve is determined by comparing the baseline values associated with the input electric current, the output electric current, and the position signals with subsequently measured values associated with the input electric current, the output electric current, and the position signals.

A method for monitoring health of a valve is presented. The method includes receiving an acoustic emission signal from a sensing device operatively coupled to the valve, selecting a region of interest signal in the acoustic emission signal, determining a plurality of current parameters based on the region of interest signal, and monitoring the health of the valve based on at least the plurality of current parameters, wherein the region of interest signal comprises acoustic emission data generated from initiation of an opening of the valve until the valve is partially opened.

A valve control is configured for use with control valves and other flow controls. The valve control leverages a simplified structure to avoid problems with manufacture and reduce costs. This structure includes a support unit that compresses parts of a valve housing together. Inside of the valve housing, the structure incorporates diaphragms that cause a pair of balanced valves to move in response to changes in pressure of fluid in a conduit. For industrial application, the valve control finds use to maintain pressure of natural gas in pipelines downstream from a control valve.

A valve for adjusting a fluid flow. The valve includes a valve body, a flow having an inlet and an outlet located downstream of the inlet, a flow adjustment arrangement for adjusting the flow of liquid from the inlet to the outlet, wherein liquid upstream of the flow adjustment arrangement but downstream of the inlet has an upstream pressure, and liquid downstream of said flow adjustment arrangement but upstream of the outlet has a downstream pressure, a stationary differential pressure sensor configured to measure a pressure difference between the upstream pressure and the downstream pressure, and a pair of pressure ports for enabling temporary connection of a non-stationary differential pressure sensor for measuring the pressure difference between the upstream pressure and the downstream pressure. Also a method for use with such a valve.

A diagnostic method for solenoid valves includes detecting, at excitation of the solenoid, a variation rate of the supply voltage of the solenoid and comparing it with a predetermined value, generating an error signal if the variation rate is lower than the predetermined value, otherwise, detecting characteristics of the waveform of the solenoid current over a time interval between a moment of excitation of the solenoid and a moment wherein the movable core reaches end-stroke position, comparing the detected characteristics with threshold values, generating an alarm signal if the detected characteristics are lower than the threshold values, otherwise calculating the value of solenoid resistance and comparing it with a minimum resistance value and a maximum resistance value when the solenoid current is in steady state, and generating an alarm signal if the solenoid resistance value is lower than the minimum resistance value or greater than the maximum resistance value.

A seal assembly includes: a seal element; a part to be sealed; and a measuring arrangement for monitoring an aging of the seal element. The seal element is held on the part so as to provide a contact stress between the seal element and the part. The seal element has a contact face with which the seal element bears against the part. At least one measuring component of the measuring arrangement is integrated in each case into the seal element and into the part. The contact face of the seal element has a surface geometry with depressions.

A safety valve is provided with an electronic control unit for generating a control voltage. An electro-fluidic preliminary stage has a piezo bending actuator which can be actuated between a working position and a safety position by the control voltage and influences the flow of a secondary control fluid flow depending on its position. A fluid-mechanical main stage has an influencing device for influencing the flow of a primary working fluid flow. The influencing device can be actuated by means of the secondary control fluid flow which flows into a control chamber of the main stage. The control unit caries out a test of the preliminary stage repeatedly in an iterative manner after the expiration of a specified time interval. As part of the functionality test, the position of the piezo bending actuator is changed slightly by varying the control voltage.

A valve fault detection method includes: constructing a valve fault indicator system reflecting characteristics of vibration signals of valve states; establishing an LSTM-AE model by using an LSTM deep model and according to an autoencoder principle, and setting a fault discrimination threshold; inputting training data into the LSTM-AE model based on the valve fault indicator system, to train the LSTM-AE model; and inputting detection data of a to-be-detected valve into the trained LSTM-AE model based on the valve fault indicator system, and comparing an output value obtained by the LSTM-AE model with the set fault discrimination threshold, to judge whether the detected valve is faulty and outputting a first judgment result.

A device for measuring a state of a valve may include a housing configured to connect to a handle of a valve or a body of a valve, a sensor supported on one of the housing or the valve stem, and an indicator detectable by the sensor. The indicator may be configured to move relative to the sensor in response to movement of a valve stem or valve handle during opening and closing of the valve. The sensor may be configured to detect a position of the indicator to determine a state of the valve. Related systems and methods are also described.