A device and method for preventing reverse travel of a smart locator's self-tuning stroke.

Abstract

This invention relates to the field of automated instrumentation and measurement technology, specifically to a device and method for preventing the reversed self-tuning stroke of an intelligent positioner. A valve positioner, limit switch I, and limit switch II are connected to the valve body of a cylinder-type or pneumatic diaphragm regulating valve. Limit switch I is electrically connected to limit switch node signal I, and limit switch II is electrically connected to limit switch node signal II. The positioner input signal is electrically connected to the DO template, and the positioner feedback signal is electrically connected to the AI ​​template. Limit switch node signals I and II are electrically connected to the DO template. This invention identifies and locates the fully open and fully closed positions based on the digital input template, corresponding the fully open and fully closed positions of the analog input signal to the actual open and closed positions of the regulating valve. Finally, through the DCS control system, consistency between the input signal and the corresponding valve position is achieved, completely solving the problem of reversed input signal and actual valve position caused by improper debugging.

Description

Technical Field

[0001] This invention relates to the field of automated instrumentation and measurement technology, specifically to a device and method for preventing the reverse of the self-tuning stroke of an intelligent positioner. Background Technology

[0002] Cylinder-type regulating valves and pneumatic diaphragm regulating valves play a crucial role in the automatic control systems of metallurgical enterprises. Intelligent valve positioners, as key control instruments, enable remote automatic control and regulation. For example, pneumatic diaphragm regulating valves are used for the primary and secondary guide vanes and anti-surge regulating valves of oxygen compressors, while ABB intelligent valve positioners are used for the primary and secondary guide vane regulating valves, resulting in good control performance.

[0003] Typically, for linear control valves, the valve is open when the valve stem moves upward and closed when the valve stem moves downward. However, for first- and second-stage guide vane control valves, the opposite is true: the guide vane opening decreases when the valve stem moves upward and increases when the valve stem moves downward. Therefore, the consistency between the intelligent positioner's input signal and the actual valve position in the field is crucial. However, the following problems were also revealed during actual field commissioning:

[0004] 1. Conventional self-tuning methods do not have a device to read the analog signal corresponding to the fully closed and fully open positions of the control valve. At the same time, the analog signal corresponding to the fully closed and fully open positions of the control valve is not tested. When the given signal is reversed from the valve position stroke on site, it cannot be detected in time.

[0005] 2. There is no unified debugging method or equipment, and the debugging effect is limited by the skill level.

[0006] 3. The field control valve stroke limitless feedback calibration device does not know the fully open or fully closed position of the control valve during the self-tuning process. After self-tuning, the accuracy of the control valve position is judged only by the consistency of the given signal and the feedback signal.

[0007] 4. Due to the different rapid self-tuning methods of intelligent valve positioners, the zero position of the regulating valve will be reversed. Without a calibration procedure, the problem of reversed regulating valve stroke cannot be detected in time.

[0008] 5. Currently, there is no dedicated testing system for verifying the correspondence between the control valve's setpoint signal, feedback signal, positioner display, and valve stem position. Summary of the Invention

[0009] The purpose of this invention is to provide a device and method for preventing the reverse of the self-tuning stroke of an intelligent positioner, thereby completely solving the problem of the actual valve position being reversed due to inconsistencies in the correspondence between the control valve's setpoint signal, feedback signal, positioner display, and valve stem position.

[0010] To solve the above-mentioned technical problems, the present invention provides a device for preventing the reverse direction of the self-tuning stroke of an intelligent positioner, comprising a cylinder-type or pneumatic diaphragm regulating valve, wherein a valve positioner is connected to the valve body of the cylinder-type or pneumatic diaphragm regulating valve, the valve positioner is bolted to the middle of the cylinder-type or pneumatic diaphragm regulating valve, and limit switch I and limit switch II are connected to the valve body of the cylinder-type or pneumatic diaphragm regulating valve, wherein limit switch I is located above the valve positioner, and limit switch II is located below the valve positioner.

[0011] Furthermore, the valve positioner includes positioner input and positioner feedback.

[0012] Furthermore, it also includes a limit device, which includes a limit switch node signal I and a limit switch node signal II. The limit switch I is electrically connected to the limit switch node signal I, and the limit switch II is electrically connected to the limit switch node signal II.

[0013] Furthermore, it also includes a DCS control system, which includes an AI template, an AO template, and a DO template. The positioner is electrically connected to the DO template, the positioner feedback is electrically connected to the AI ​​template, and the limit switch node signal I and limit switch node signal II are electrically connected to the DO template.

[0014] Furthermore, both limit switch I and limit switch II are connected to the valve body of the cylinder-type or pneumatic diaphragm regulating valve via clamps.

[0015] A method of using a device to prevent the self-tuning stroke of a smart locator from reversing, comprising the following steps:

[0016] S1. Reset the DCS control system. This will reset the analog signals I0 and I2 corresponding to the fully closed and fully open positions of the cylinder-type or pneumatic diaphragm control valve during automatic adjustment. 100 The reading indicates that the current is I0 when the cylinder-type or pneumatic diaphragm control valve is fully closed, and the current is I when the cylinder-type or pneumatic diaphragm control valve is fully open. 100 ;

[0017] S2. Run the cylinder-type or pneumatic diaphragm regulating valve fully open and fully closed twice.

[0018] S2.1. Record the states of limit switch I and limit switch II when the current is I0. Limit switch I and limit switch II each have two states, a and b.

[0019] a. The state corresponding to limit switch I is 0, and the state corresponding to limit switch II is 1;

[0020] b. The state corresponding to limit switch I is 1, and the state corresponding to limit switch II is 0;

[0021] S2.2. The current is I 100 The states corresponding to limit switches I and II are recorded. Limit switches I and II each have two states, a1 and b1, respectively.

[0022] a1. The state corresponding to limit switch I is 1, and the state corresponding to limit switch II is 0;

[0023] b1. The state corresponding to limit switch I is 0, and the state corresponding to limit switch II is 1;

[0024] S2.3. Connect I0 and I 100 Match and store the corresponding limit switches I and II;

[0025] S3. When performing maintenance or replacement work on valve positioners or cylinder-type or pneumatic diaphragm control valves, the positioner shall be self-tuned and the valve position shall be checked;

[0026] S4. After the maintenance or replacement work is completed, the DCS control system is calibrated. The DCS control system sends two full-stroke signals to the cylinder-type or pneumatic diaphragm control valve, one fully open and one fully closed. Then, the states corresponding to limit switches I and II are recorded. If the states corresponding to limit switches I and II are inconsistent with the data stored in step S2, the system will issue an error message, indicating that the stroke of the cylinder-type or pneumatic diaphragm control valve is incorrect and needs to be reconfirmed. If the states corresponding to limit switches I and II are consistent with the data stored in step S2, it indicates that the stroke of the cylinder-type or pneumatic diaphragm control valve is correct.

[0027] The beneficial effects of this invention are as follows: This invention mainly addresses the problem of reverse valve action after self-tuning of cylinder-type or pneumatic diaphragm control valves during on-site maintenance or valve positioner replacement, where the correspondence between the control valve's setpoint signal, feedback signal, positioner display, and valve stem position is not confirmed or cannot be determined. A solution is proposed to prevent reverse travel during valve positioner self-tuning. This device mainly includes the valve positioner's setpoint and feedback, limit switches I and II, and a DCS control system. It has the function of automatically reading and storing analog signals of the fully open and fully closed positions within the travel range of the automatic control system. Simultaneously, it identifies and locates the fully open and fully closed positions based on the digital input template, corresponding the fully open and fully closed positions of the analog setpoint signal to the actual open and closed positions of the control valve on-site. Finally, through the DCS control system, consistency between the setpoint signal and the corresponding valve position is achieved, completely solving the problem of reversed setpoint signal and actual valve position caused by improper debugging. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of the present invention;

[0029] In the diagram: 1. DCS control system; 2. AI template; 3. AO template; 4. DO template; 5. Positioner input; 6. Positioner feedback; 7. Valve positioner; 8. Cylinder-type or pneumatic diaphragm control valve; 9. Limit switch node signal I; 10. Limit switch node signal II; 11. Limit device; 12. Limit switch I; 13. Limit switch II. Detailed Implementation

[0030] like Figure 1 As shown, the present invention provides a device for preventing the reverse direction of the self-tuning stroke of an intelligent positioner, comprising a cylinder-type or pneumatic diaphragm regulating valve 8, a valve positioner 7 connected to the valve body of the cylinder-type or pneumatic diaphragm regulating valve 8, the valve positioner 7 being bolted to the middle of the cylinder-type or pneumatic diaphragm regulating valve 8, and limit switches I 12 and II 13 connected to the valve body of the cylinder-type or pneumatic diaphragm regulating valve 8, the limit switch I 12 being located above the valve positioner 7, and the limit switch II 13 being located below the valve positioner 7.

[0031] Furthermore, the valve positioner 7 includes a positioner input 5 and a positioner feedback 6.

[0032] Furthermore, it also includes a limit device 11, which includes a limit switch node signal I9 and a limit switch node signal II10. The limit switch I12 is electrically connected to the limit switch node signal I9, and the limit switch II13 is electrically connected to the limit switch node signal II10.

[0033] Furthermore, it also includes a DCS control system 1, which includes an AI template 2, an AO template 3, and a DO template 4. The positioner input 5 is electrically connected to the DO template 4, the positioner feedback 6 is electrically connected to the AI ​​template 2, and the limit switch node signal I 9 and the limit switch node signal II 10 are electrically connected to the DO template 4.

[0034] Furthermore, both limit switches I12 and II13 are connected to the valve body of the cylinder-type or pneumatic diaphragm regulating valve 8 via clamps.

[0035] A method of using a device to prevent the self-tuning stroke of a smart locator from reversing, comprising the following steps:

[0036] S1. Perform a reset operation on the DCS control system 1. At this time, the analog signals I0 and I1 corresponding to the fully closed and fully open positions of the cylinder-type or pneumatic diaphragm regulating valve 8 during automatic adjustment will be completed. 100 The reading indicates that when the cylinder-type or pneumatic diaphragm regulating valve 8 is fully closed, the corresponding current is I0; and when the cylinder-type or pneumatic diaphragm regulating valve 8 is fully open, the corresponding current is I... 100 ;

[0037] S2. The cylinder-type or pneumatic diaphragm regulating valve 8 is fully opened and fully closed twice.

[0038] S2.1. Record the states of limit switches I12 and II13 corresponding to the current I0. Limit switches I12 and II13 each have two states, a and b.

[0039] a. The state corresponding to limit switch I12 is 0, and the state corresponding to limit switch II13 is 1;

[0040] b. The state corresponding to limit switch I12 is 1, and the state corresponding to limit switch II13 is 0;

[0041] S2.2. The current is I 100 The states corresponding to limit switches I12 and II13 are recorded. Limit switches I12 and II13 each have two states: a1 and b1.

[0042] a1. The state corresponding to limit switch I12 is 1, and the state corresponding to limit switch II13 is 0;

[0043] b1. The state corresponding to limit switch I12 is 0, and the state corresponding to limit switch II13 is 1;

[0044] S2.3. Connect I0 and I 100Match and store the corresponding limit switches I12 and II13;

[0045] S3. When performing maintenance or replacement work on valve positioner 7 or cylinder-type or pneumatic diaphragm control valve 8, perform self-tuning on positioner 7 and check valve position;

[0046] S4. After the maintenance or replacement work is completed, the DCS control system 1 is calibrated. The DCS control system 1 sends two full-stroke signals to the cylinder-type or pneumatic diaphragm control valve 8, namely fully open and fully closed. Then, the states corresponding to limit switches I12 and II13 are recorded. If the states corresponding to limit switches I12 and II13 are inconsistent with the data stored in step S2, the system will issue an error reminder, indicating that the stroke of the cylinder-type or pneumatic diaphragm control valve 8 is incorrect and needs to be reconfirmed. If the states corresponding to limit switches I12 and II13 are consistent with the data stored in step S2, it indicates that the stroke of the cylinder-type or pneumatic diaphragm control valve 8 is correct.

[0047] The positioner setpoint 5 and positioner feedback 6 are output as setpoint signals by the AO template 3 of the DCS control system 1 and received as feedback signals by the AI ​​template 2. They are mainly used to read the analog signals corresponding to the fully closed and fully open positions of the regulating valve in the automatic control system during reset. They are also output as setpoint signals for the valve positioner 7 through the output channel of the AO template 3, and the positioner feedback 6 is received through the AI ​​template 2.

[0048] The fully open and fully closed limit device consists of two limit switches, namely limit switch I12 and limit switch II13, which are fixed with stainless steel clamps and iron hoops. It is convenient to use in the stroke test of cylinder or pneumatic diaphragm control valves of different models and specifications. It is mainly used for the detection of the two ends of the valve position on site. By identifying and memorizing the fully open and fully closed positions, it provides a basis for the execution of the calibration procedure.

[0049] The DCS control system 1 reads and records the analog signals corresponding to the fully open and fully closed states of the cylinder-type or pneumatic diaphragm control valve 8 in the program. At the same time, it matches the positions of the limit switches I12 and II13 installed on site with the analog signals to form the unique key parameters of the cylinder-type or pneumatic diaphragm control valve 8 being tested, which have memory and judgment functions.

[0050] The DCS control system 1 tests the control stroke of the valve positioner 7 after commissioning. By retrieving the correspondence between the analog signal of the DCS control system 1 and the actual valve position, the correctness of the valve position is confirmed. It has accurate judgment capability and will trigger an alarm when the given signal is inconsistent with the actual valve position on site.

Claims

1. A device for preventing the reverse direction of the self-tuning stroke of an intelligent positioner, characterized in that: The system includes a cylinder-type or pneumatic diaphragm regulating valve (8), a valve positioner (7) connected to the valve body of the cylinder-type or pneumatic diaphragm regulating valve (8), the valve positioner (7) being bolted to the middle of the cylinder-type or pneumatic diaphragm regulating valve (8), and limit switches I (12) and II (13) connected to the valve body of the cylinder-type or pneumatic diaphragm regulating valve (8). Limit switch I (12) is located above the valve positioner (7), and limit switch II (13) is located below the valve positioner (7). The valve positioner (7) includes a positioner setpoint (5) and a positioner feedback (6), and also includes a limit device (11). The limit device (11) includes a limit switch node signal I (9) and a limit switch node signal II (10). The limit switch I (12) is electrically connected to the limit switch node signal I (9), and the limit switch II (13) is electrically connected to the limit switch node signal II (10). The system also includes DCS control. The system (1), the DCS control system (1) includes an AI template (2), an AO template (3) and a DO template (4). The positioner input (5) is electrically connected to the DO template (4). The positioner feedback (6) is electrically connected to the AI ​​template (2). The limit switch node signal I (9) and limit switch node signal II (10) are electrically connected to the DO template (4). The limit switch I (12) and limit switch II (13) are both connected to the valve body of the cylinder or pneumatic diaphragm regulating valve (8) through clamps. The DCS control system (1) reads and records the analog signals corresponding to the cylinder or pneumatic diaphragm regulating valve (8) when it is fully open and fully closed in the program. The DCS control system (1) matches the positions corresponding to the limit switch I (12) and limit switch II (13) with the analog signals to form the parameters of the cylinder or pneumatic diaphragm regulating valve (8) being debugged, and has memory and judgment functions.

2. The method of using the device for preventing reverse travel of the self-tuning stroke of a smart positioner according to claim 1, characterized in that: The steps include the following: S1. Perform a reset operation on the DCS control system (1). At this time, the analog signals I0 and I2 corresponding to the fully closed and fully open positions of the cylinder-type or pneumatic diaphragm regulating valve (8) during automatic adjustment will be completed. 100 The reading is as follows: when the cylinder-type or pneumatic diaphragm regulating valve (8) is fully closed, the corresponding current is I0; when the cylinder-type or pneumatic diaphragm regulating valve (8) is fully open, the corresponding current is I... 100 ; S2. The cylinder-type or pneumatic diaphragm regulating valve (8) is fully opened and fully closed twice. S2.

1. Record the states of limit switch I (12) and limit switch II (13) when the current is I0. Limit switch I (12) and limit switch II (13) have two states, a and b respectively. a. The state corresponding to limit switch I (12) is 0, and the state corresponding to limit switch II (13) is 1; b. The state corresponding to limit switch I (12) is 1, and the state corresponding to limit switch II (13) is 0; S2.

2. The current is I 100 The states corresponding to limit switches I (12) and II (13) are recorded. Limit switches I (12) and II (13) each have two states, a1 and b1, respectively. a1. The state corresponding to limit switch I (12) is 1, and the state corresponding to limit switch II (13) is 0; b1. The state corresponding to limit switch I (12) is 0, and the state corresponding to limit switch II (13) is 1; S2.

3. Connect I0 and I 100 The corresponding limit switches I (12) and II (13) are matched and stored; S3. When performing maintenance or replacement work on the valve positioner (7) or the cylinder or pneumatic diaphragm regulating valve (8), the positioner (7) is self-tuned and the valve position is checked. S4. After the maintenance or replacement work is completed, the DCS control system (1) is calibrated. The DCS control system (1) gives the cylinder or pneumatic diaphragm regulating valve (8) two full-stroke signals, namely fully open and fully closed. Then, the states corresponding to limit switch I (12) and limit switch II (13) are recorded respectively. If the states corresponding to limit switch I (12) and limit switch II (13) are inconsistent with the data stored in step S2, the system will issue an error reminder, indicating that the stroke of the cylinder or pneumatic diaphragm regulating valve (8) is incorrect and needs to be reconfirmed. If the states corresponding to limit switch I (12) and limit switch II (13) are consistent with the data stored in step S2, it indicates that the stroke of the cylinder or pneumatic diaphragm regulating valve (8) is correct.

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