Methods and apparatus of assessing a test of a solenoid valve via a positioner

Patent metadata

Field	Value
Publication number	US-10234058-B2
Application number	US-201615298726-A
Country	US
Kind code	B2
Filing date	Oct 20, 2016
Priority date	Oct 20, 2016
Publication date	Mar 19, 2019
Grant date	Mar 19, 2019

Abstract

Methods and apparatus of assessing a test of a solenoid valve via a positioner are disclosed. An example apparatus includes a solenoid valve to enable an actuator to close an emergency valve and a valve positioner fluidly and communicatively coupled to the solenoid valve. The valve positioner is to instruct the solenoid valve to transition the solenoid valve from a first state to a second state. The valve positioner is to monitor a pressure change of a pressure chamber of the actuator in fluid communication with the solenoid valve relative to an initial pressure for a monitoring duration. The valve positioner is to identify a maximum pressure change during the monitoring duration and determine a ready state of the solenoid valve when the maximum pressure change is greater than a minimum trip value and the pressure change at a monitoring end time is less than a maximum reset value.

First claim

What is claimed is:

1. An apparatus comprising:
a solenoid valve to enable an actuator to close an emergency valve; and
a valve positioner fluidly and communicatively coupled to the solenoid valve, the valve positioner to:
instruct the solenoid valve for a pulse duration to transition the solenoid valve from a first state to a second state, the pulse duration extending from a start time to a pulse end time, the solenoid valve to transition from the second state to the first state upon completion of the pulse duration;
monitor a pressure change of a pressure chamber of the actuator in fluid communication with the solenoid valve relative to an initial pressure for a monitoring duration that extends from the start time to a monitoring end time;
determine a maximum pressure change during the monitoring duration;
determine the pressure change at the monitoring end time;
compare the maximum pressure change to a minimum trip value;
compare the pressure change at the monitoring end time to a maximum reset value; and
determine a ready state or an error state of the solenoid valve based on whether the maximum pressure change is greater than the minimum trip value and whether the pressure change at the monitoring end time is less than the maximum reset value.

2. The apparatus of claim 1 , wherein the valve positioner is to determine the error state in response to determining that the maximum pressure change is less than the minimum trip value or that the pressure change at the monitoring end time is greater than the maximum reset value.

3. The apparatus of claim 1 , wherein the monitoring end time is subsequent to the pulse end time.

4. The apparatus of claim 1 , wherein the valve positioner is to:
determine the maximum pressure change by comparing the initial pressure of the pressure chamber to a minimum pressure of the pressure chamber measured during the monitoring duration; and
determine the pressure change at the monitoring end time by comparing the initial pressure of the pressure chamber to a pressure of the pressure chamber measured at the monitoring end time.

5. The apparatus of claim 1 , wherein the valve positioner is further to:
compare the maximum pressure change to a maximum trip value; and
determine the ready state or the error state of the solenoid valve based further on whether the maximum pressure change is less than the maximum trip value, the minimum trip value being approximately half the maximum trip value.

6. The apparatus of claim 1 , wherein the maximum reset value is approximately twice a nominal pressure change relative to the initial pressure.

7. The apparatus of claim 1 , wherein the valve positioner is to test the solenoid valve without causing the solenoid valve to actuate the emergency valve.

8. The apparatus of claim 1 , wherein the valve positioner is to test the solenoid valve independently of testing the emergency valve.

9. A method comprising:
instructing, by executing first instructions via a processor of a valve positioner, a solenoid valve for a pulse duration to transition from a first state to a second state, the solenoid valve to enable an actuator to close an emergency valve, the pulse duration extending from a start time to a pulse end time;
instructing, by executing second instructions via the processor, the solenoid valve to transition from the second state to the first state at the pulse end time;
monitoring, by executing third instructions via the processor, a pressure change of a pressure chamber of the actuator in fluid communication with the solenoid valve relative to an initial pressure for a monitoring duration that extends from the start time to a monitoring end time;
determining, by executing fourth instructions via the processor, a maximum pressure change during the monitoring duration;
determining, by executing fifth instructions via the processor, the pressure change at the monitoring end time;
comparing, by executing sixth instructions via the processor, the maximum pressure change to a minimum trip value;
comparing, by executing seventh instructions via the processor, the pressure change at the monitoring end time to a maximum reset value; and
determining, by executing eighth instructions via the processor, a ready state or an error state of the solenoid valve based on whether the maximum pressure change is greater than the minimum trip value and whether the pressure change at the monitoring end time is less than the maximum reset value.

10. The method of claim 9 , further including determining the error state in response to determining that the maximum pressure change is less than the minimum trip value or that the pressure change at the monitoring end time is greater than the maximum reset value.

11. The method of claim 10 , wherein determining that the maximum pressure change is less than the minimum trip value indicates that the solenoid valve is slow to cause the actuator to close the emergency valve.

12. The method of claim 10 , wherein determining that the pressure change at the monitoring end time is greater than the maximum reset value indicates that the solenoid valve is slow to cause the actuator to reopen the emergency valve upon closing.

13. The method of claim 9 , wherein the monitoring end time is subsequent to the pulse end time.

14. The method of claim 9 , wherein determining the maximum pressure change includes calculating a difference between the initial pressure of the pressure chamber and a minimum pressure of the pressure chamber measured during the monitoring duration.

15. The method of claim 9 , wherein determining the pressure change at the monitoring end time includes calculating a difference between the initial pressure of the pressure chamber and a pressure of the pressure chamber measured at the monitoring end time.

16. The method of claim 9 , further including:
comparing the maximum pressure change to a maximum trip value; and
determining the ready state or the error state of the solenoid valve based further on whether the maximum pressure change is less than the maximum trip value, the minimum trip value being approximately half the maximum trip value.

17. The method of claim 9 , wherein the maximum reset value is approximately twice a nominal pressure change relative to the initial pressure.

18. The method of claim 9 , wherein the determining of the ready state or the error state of the solenoid valve enables the solenoid valve to be tested when there is at least one of a varying upstream flow, a varying downstream flow, a delay in communication between the valve positioner and the solenoid valve, or a mechanical delay in transitioning the solenoid valve between the first state and the second state.

19. An apparatus comprising:
means for actuating an actuator to close an emergency valve; and
means for positioning fluidly and communicatively coupled to the means for actuating, the means for positioning to:
instruct the means for actuating for a pulse duration to transition the means for actuating from a first state to a second state, the pulse duration extending from a start time to a pulse end time, the means for actuating to transition from the second state to the first state upon completion of the pulse duration;
monitor a pressure change of a pressure chamber of the actuator in fluid communication with the means for actuating relative to an initial pressure for a monitoring duration that extends from the start time to a monitoring end time;
determine a maximum pressure change during the monitoring duration;
determine the

Assignees

• Fisher Controls Int Llc

Inventors

• Junk Kenneth
• Jelken Shannon

Classifications

• F16K11/044

  with movable valve members positioned between valve seats · CPC title

• F15B2211/855

  Testing of fluid pressure systems · CPC title

• F15B2211/6313

  the pressure being a load pressure · CPC title

• F15B2211/857

  Monitoring of fluid pressure systems · CPC title

• F16K31/0627

  with movable valve member positioned between seats · CPC title