Integrated process control valve

A process control valve comprising

• a fluid valve body having an inlet for receiving fluid, an outlet for discharging fluid, a fluid flow passage connecting the inlet and outlet, and a controllable throttling element which is moveable to selectively vary the cross-sectional area of flow of at least a portion of the passage,
• actuator means coupled to the valve body and responsive to control signals for selectively moving the throttling element,
• a temperature sensor for producing a temperature signal representing the temperature T.sub.1 of the fluid in the fluid flow passage, and
• utilization means for receiving said temperature signal for developing an output dependent upon the received temperature signal and for producing control signals for application to the actuator means.

A process control valve comprising

• a fluid valve body having an inlet for receiving fluid, an outlet for discharging fluid, a fluid flow passage connecting the inlet and outlet, and a controllable throttling element which is moveable to selectively vary the cross-sectional area of flow of at least a portion of the passage,
• actuator means coupled to the valve body and responsive to control signals for selectively moving the throttling element,
• at least one sensor disposed in the valve body for producing at least one characterizing signal representing at least one physical parameter of the valve body and/or fluid present in the valve body, and
• utilization means for receiving said characterizing signals and for developing an output dependent upon the received characterizing signals, wherein said utilization means is disposed on the valve and comprises stored program control means for receiving said characterizing signals and for producing control signals for application to the actuator means to cause it to move the throttling element in a manner dependent upon the values of the characterizing signals.

In combination with a flow control valve having a valve body with an inlet, outlet and valve passage for carrying fluid from the inlet to the outlet, a valve plug moveable to selectively vary the size of the valve passage through which fluid flows to thereby vary the rate of fluid flow through the valve, a valve actuator responsive to pneumatic control signals for developing a pressure to selectively move the valve plug, and a valve positioner responsive to command signals for producing pneumatic control signals from an air supply source for application to the valve actuator,

• a valve diagnostic system comprising
• means for producing signals indicating the position of the valve plug,
• first means disposed in the valve body for producing signals indicating the pressure of fluid at the valve body inlet,
• second means disposed in the valve body for producing signals indicating the pressure of fluid at the valve body outlet,
• means for storing said position signals and inlet and outlet pressure signals, and
• means for displaying representations of the inlet and outlet pressure signals for selected positions of the valve plug.

A method for diagnostic testing of a fluid control valve through which fluid flows and which is operated by an actuator in response to actuation signals, said method comprising

• (a) applying predetermined actuation signals to the actuator of said valve,
• (b) detecting and storing a first set of valve parameter values which are developed in said valve as the valve is operated in response to the predetermined actuation signals,
• (c) detecting and storing subsequent sets of valve parameter values developed at selected times upon subsequent operation of the valve, and
• (d) displaying said first set valve parameter values and selected ones of said subsequent sets of valve parameter values.

In combination in a fluid control valve which is operated by an actuator in response to actuation signals, tester apparatus for testing and analyzing the valve comprising

• means for sending controlled actuation signals to the actuator to cause the actuator to operate the valve,
• sensor means disposed in the valve for measuring of specific valve parameters upon operation of the valve,
• means for storing the measured valve parameters, and
• means for displaying the stored valve parameters.

A method of controlling the operation of a flow control valve having a valve body with an inlet, outlet and passageway therebetween for carrying fluid, a valve throttling means disposed in the passageway and being selectively moveable to various positions to vary the flow volume of fluid through the valve body, an actuator responsive to command signals for moving the throttling means in accordance with the command signals, sensor means disposed in the valve body for measuring fluid pressure P.sub.i at the inlet, fluid pressure P.sub.o at the outlet, and temperature T of the fluid in the passageway, position sensing means for measuring the percentage p at which the throttling means is open, ranging from 0 to 100 percent, and microprocessor means for receiving and storing the measurements P.sub.i, P.sub.o and T and p and for producing command signals to control the operation of the valve, said method comprising

• (a) measuring P.sub.i, P.sub.o and T for a selected value of p and storing said measurements and the value of p for which the measurements
• (b) calculating the fluid flow rate Q.sub.c through the valve for the selected value of p using the stored measurements, and storing the calculated Q.sub.c,
• (c) storing a predetermined flow rate value Q.sub.s,
• (d) comparing Q.sub.c with Q.sub.s and supplying command signals to the actuator to further open the throttling means by a predetermined percentage if Q.sub.c is less than Q.sub.s, and to further close throttling means by a predetermined percentage if Q.sub.c is greater than Q.sub.s.

In a fluid system having a fluid source and a fluid sink, flow control valve apparatus comprising

• a valve body coupled between the fluid source and fluid sink for carrying fluid therethrough, having a control element which is moveable to vary the flow rate of the fluid through the valve body,
• actuator means coupled to the valve body and responsive to control signals for selectively moving the control element,
• at least one sensor disposed in the valve body for developing first signals representing at least one parameter of the fluid in the valve body,
• at least one sensor disposed in the fluid system outside the valve body for developing second signals representing at least one parameter of the fluid outside the valve bodies, and
• processing means for receiving said first and second signals and for producing an output action in response thereto.