Diagnostic apparatus and method for fluid control valves
First Claim
1. A method for diagnostically dynamic testing and determining the dynamic operating condition of a pneumatically operated fluid control valve assembly having a valve actuator connected to a valve flow control member for movement between respective closed and open valve positions, and a valve positioner pneumatically coupled to said valve actuator, said method comparing a dynamic output of said valve assembly in response to a dynamic input to said valve assembly comprising the step of:
- providing a controlled variable pneumatic pressure to the input of the valve positioner forming a dynamic input to said valve assembly to operate the valve in a dynamic test operation cycle defined by removing the flow control member between said respective closed and open valve positions;
providing a pressure sensor to sense said controlled varying pressure at the input of the valve positioner;
providing a position sensor to sense movement of the flow control member representing a dynamic output of said valve assembly;
obtaining a first signal from the pressure sensor corresponding to said controlled varying pressure at the valve positioner input during the dynamic test operation cycle;
obtaining a second signal from the position sensor corresponding to movement of the flow control member in response to said dynamic input to said valve assembly during the dynamic test operating cycle;
processing said first signal and said second signal to derive valve diagnostic data representing the movement of the flow control member during the dynamic test operation cycle as a function of the variation in said controlled variable pneumatic pressure to the input of the valve positioner; and
displaying said valve diagnostic data for enabling determination of the dynamic performance of said valve assembly positioner under test.
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Accused Products
Abstract
Apparatus and method for diagnostically testing and determining the operating condition of a pneumatically operated valve. A diagnostic controller is connected to a valve actuator assembly so that diaphragm pressure and valve plug movement among other inputs can be sensed while the valve actuator assembly is stroked through a test operation cycle. The sensor output signals are then used in selected graphical plots to provide information which can be analyzed to indicate the condition of the valve in such areas as spring adjustment, stroking time, valve travel, stem friction, seat load, and positioner and transducer calibration.
306 Citations
6 Claims
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1. A method for diagnostically dynamic testing and determining the dynamic operating condition of a pneumatically operated fluid control valve assembly having a valve actuator connected to a valve flow control member for movement between respective closed and open valve positions, and a valve positioner pneumatically coupled to said valve actuator, said method comparing a dynamic output of said valve assembly in response to a dynamic input to said valve assembly comprising the step of:
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providing a controlled variable pneumatic pressure to the input of the valve positioner forming a dynamic input to said valve assembly to operate the valve in a dynamic test operation cycle defined by removing the flow control member between said respective closed and open valve positions; providing a pressure sensor to sense said controlled varying pressure at the input of the valve positioner; providing a position sensor to sense movement of the flow control member representing a dynamic output of said valve assembly; obtaining a first signal from the pressure sensor corresponding to said controlled varying pressure at the valve positioner input during the dynamic test operation cycle; obtaining a second signal from the position sensor corresponding to movement of the flow control member in response to said dynamic input to said valve assembly during the dynamic test operating cycle; processing said first signal and said second signal to derive valve diagnostic data representing the movement of the flow control member during the dynamic test operation cycle as a function of the variation in said controlled variable pneumatic pressure to the input of the valve positioner; and displaying said valve diagnostic data for enabling determination of the dynamic performance of said valve assembly positioner under test. - View Dependent Claims (2, 3, 4, 5, 6)
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Specification