CN115586754A - Pneumatic valve fault pre-judging system and pre-judging method based on DCS control - Google Patents

Abstract

The invention relates to the technical field of valve fault diagnosis in a pipeline fluid delivery system, and specifically discloses a pneumatic valve fault prediction system and a prediction method based on DCS control. The pneumatic valve fault prediction system includes a feedback mechanism and a pressure transmitter. , safety barrier, wiring terminal block, DCS control system and operation terminal, the feedback mechanism is set on the pneumatic piston actuator of the pneumatic valve, and the pressure transmitter is set at the end of the gas path of the pneumatic valve; the pneumatic valve based on DCS control designed by the present invention The structure of the valve fault prediction system is simple to change, the overall investment is low, and it is convenient to use and maintain. It improves the intelligence of the equipment and further strengthens the safe production of the post. It can be widely applied to other valve fault prediction design requirements based on the DCS control system, especially for aerospace. Sequence control valves for pulverized coal pressurized conveying and slagging process devices such as furnaces and shell furnaces.

Description

A Pneumatic Valve Fault Prediction System and Prediction Method Based on DCS Control

technical field

The invention relates to the technical field of fault diagnosis of valves in pipeline fluid conveying systems, and specifically discloses a fault prediction system suitable for pneumatic valves in pulverized coal conveying sequence control and slag lock sequence control in pulverized coal pressurized gasification and its passing through The method of the system for fault prediction.

Background technique

The valve is the control component of the pipeline fluid delivery system. It is used in the pipeline fluid delivery system to achieve the functions of diversion, cut-off, throttling, check, diversion and pressure relief. Its importance is self-evident.

In the pulverized coal delivery sequence control and slag lock sequence control of the pulverized coal pressurized gasification device, there are many cut-off valves that need to be switched frequently. These valves are mostly pneumatic piston actuator ball valves with large diameter and piston output force. Large, frequent valve action, so after a long time of operation, it is easy to leak air from the cylinder O-ring, the wear gap of the valve fork becomes larger, and the connection between the valve cylinder and the valve body is loose, and then it is prone to failure. In the pulverized coal pressurized gasification device, once a problem occurs in a link of the valve and is not found and dealt with in time, it will lead to further expansion of the fault phenomenon until the valve cannot operate, affecting production, and even triggering the shutdown of the device to force production to be interrupted.

At present, relevant enterprises cannot realize fault prediction and diagnosis of pneumatic valves in pulverized coal pressurized gasification devices. They can only avoid a series of problems caused by pneumatic valve failures through regular shutdown maintenance and repair, but such operations cannot be effectively guaranteed Normal operation of pulverized coal pressurized gasification process. In order to avoid similar situations, our technicians designed a pneumatic valve fault prediction system based on DCS control according to the characteristics of the pneumatic piston actuator, and completed the valve state screening through the valve fault pre-judgment, so that relevant personnel can diagnose the fault. Valves are inspected and repaired in advance to avoid the expansion of faults and problems, thereby ensuring the safe and stable operation of the pulverized coal pressurized gasification process.

Contents of the invention

The present invention aims to provide a pneumatic valve fault prediction system based on DCS control. The system pre-judges and completes the valve state screening according to the characteristics of the pneumatic piston actuator in the pneumatic valve, and checks and repairs the faulty valve in advance to avoid faults. The problem expands.

The present invention is achieved through the following technical solutions:

A pneumatic valve fault prediction system based on DCS control, including a feedback mechanism, a pressure transmitter, a safety barrier, a terminal block, a DCS control system and an operation terminal, and the feedback mechanism is set on the pneumatic piston actuator of the pneumatic valve , the pressure transmitter is arranged at the end of the gas circuit of the pneumatic valve, the feedback mechanism and the pressure transmitter are electrically connected to the corresponding safety barrier, and the safety barrier is electrically connected to the corresponding terminal, so The terminal block is electrically connected to the DCS control system, and the DCS control system is electrically connected to the man-machine interface of the operation terminal.

As the specific setting above, the feedback mechanism includes open feedback and close feedback, the open feedback and close feedback are respectively electrically connected to the corresponding safety barriers through cables, and the safety barriers corresponding to the open feedback and close feedback are connected to the same The terminal blocks are electrically drained.

As the specific setting above, the terminal block corresponding to the feedback mechanism is connected to the DI card of the DCS control system through a cable, and the terminal block corresponding to the pressure transmitter is connected to the AI card of the DCS control system through a cable superior.

The invention also discloses a method for predicting the failure of a pneumatic valve based on DCS control, which includes the following steps:

S1: Detect the on/off state of the pneumatic valve through the feedback mechanism, and transmit it to the corresponding safety barrier, and then transmit the on/off state feedback information received on the safety barrier to the corresponding configuration of the DCS control system On the DI card channel, perform remote receiving detection;

S2: Detect the air source pressure at the end of the air path of the pneumatic valve through a pressure transmitter, and connect it to the DCS control system through a safety barrier, cable, and AI card to perform remote monitoring of the air source pressure;

S3: Perform point information configuration in the DCS control system, and perform equipment control configuration according to the process interlock control situation, and ensure that the configured point channel information corresponds to the actual situation;

S4: After the pneumatic valve is put into normal operation, count and time the actual opening/closing action time of the pneumatic valve as the basis for its fault judgment setting value;

S5: Design the judgment logic and set up the time parameters for the opening/closing process of the pneumatic valve. When the air source pressure at the end of the air circuit is normal, when the system issues a valve opening/closing command, the judgment logic starts timing judgment, such as the time when the pneumatic valve opening/closing feedback is in place When it is less than the set value, the alarm will not be triggered. If the pneumatic valve open/close feedback time is greater than the set value, the alarm will be triggered;

S6: Set up alarm counting data, each time an alarm message occurs, the data is accumulated once, so as to facilitate long-term tracking and observation of the valve action time;

S7: Add an interface for alarm count data and fault judgment time parameters on the operation terminal.

As a specific setting of the above solution, the point information configured in the step 3 includes the valve opening feedback state, the valve closing feedback state, the valve opening command, and the valve closing command.

As a specific setting of the above scheme, if the air source pressure at the end of the air path in step 5 is higher than the set pressure value, it is judged to be normal, and the set pressure value is determined by the maximum required by the pneumatic piston actuator in the pneumatic valve. The air source pressure is determined.

As a further setting of the above scheme, in the step 7, functions of clearing the alarm count data and historical query are also added on the operation terminal. The specific alarm count data clearing and historical query functions can only be operated under the authority of the engineer, and the fault judgment time parameter With readable and writable functions, the action time can be modified in time after the valve is replaced and the action characteristic parameters change.

The patent of the present invention is based on the existing DCS control system. Under certain conditions, the pneumatic valve action switch time is used as the basis for judgment, and the valve opening (closing) process time is compared with the system preset time range, and the timeout record . The valve fault prediction system is set on the valves of important positions that are frequently used and frequently operated, and the above-mentioned action time diagnosis mechanism is set up, which can predict the faults of the valves in advance, avoid the expansion of valve faults, and ensure the safety of valves as important control components. The function is put into use normally.

Beneficial effect:

The pneumatic valve fault prediction system based on DCS control designed by the present invention only needs to add a feedback mechanism on the corresponding pneumatic valve and a pressure transmitter at the end of the gas path of the pneumatic valve, so that the entire pulverized coal pressurized gas The structural modification of the chemical device is simple, and the logical judgment and control are configured based on the existing DCS control system, which makes the overall investment low, easy to use and maintain, improves the intelligence of the equipment, and further strengthens the safety of the post. In addition, the present invention has strong applicability, and can be widely applied to other valve failure prediction design requirements based on DCS control systems, and is especially suitable for sequential control valves of pulverized coal pressurized conveying and slagging process devices such as aerospace furnaces and shell furnaces.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings that are required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. Those of ordinary skill in the art can also obtain other drawings based on these drawings without any creative effort.

Fig. 1 is the connection schematic diagram of the valve fault prediction system hardware of the present invention;

Fig. 2 is a schematic diagram of the logic judgment of the valve fault prediction system of the present invention.

detailed description

In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiment of the application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the application. Obviously, the described embodiment is only It is an embodiment of a part of the application, but not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the scope of protection of this application.

It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to accompanying drawings 1-2 and in conjunction with embodiments.

Example 1

The invention discloses a pneumatic valve fault prediction system based on DCS control. The system is composed of two parts: valve fault prediction system hardware and valve fault prediction system logic judgment setting. The following is combined with accompanying drawing 1 and accompanying drawing 2 Explain the two parts separately.

Referring to accompanying drawing 1, this system includes pneumatic piston actuator 1 in pneumatic valve, feedback mechanism 2, open feedback 3, close feedback 4, control cables 5 and 6, safety barrier 7 and 8, pressure transmitter 12, control cable 13. Safety barrier 14, terminal boards 9 and 15, bundled cables 10 and 16, DI card 11, AI card 17, operation terminal 18 and DCS control system 19.

In the specific setting, the feedback mechanism 2 is installed on the pneumatic piston actuator 1, and the feedback mechanism 2 is provided with two parts: the opening feedback 3 and the closing feedback 4. The opening feedback 3 and the closing feedback 4 of the valve pass through the control cable 5 and the 6 is connected to the corresponding safety barriers 7 and 8, and then the feedback signals received by the safety barriers 7 and 8 are connected to the same terminal board 9 through cables, and the terminal board 9 sends the feedback signals to the DCS control through the bundled cables 10 On the DI card 11 on the system 19. The pressure transmitter 12 is arranged at the end of the gas path of the pneumatic valve, and is connected to the safety barrier 14 through the control cable 13, and the safety barrier 14 connects the received pressure signal to the terminal board 15 through the cable, and the terminal board 15 connects the The pressure signal is sent to the AI card 17 on the DCS control system 19 . Finally, the DI card 11 and the AI card 17 will judge and monitor the received signal in the DCS control system 19 through the configured control logic, and connect to the operation terminal 18 through the network cable 20, and display it through the man-machine interface. operate.

Referring to Figure 2, the logic judgment setting of the valve failure prediction system is composed of equipment feedback A, logic judgment B, and human-computer interaction interface monitoring C. Since other related control logics of pneumatic valves in production have nothing to do with the failure prediction system, this paper does not Not specified.

The equipment feedback control A is implemented as follows; the input terminal of the equipment controller 1e respectively receives the valve opening feedback 1a and the valve closing feedback 1b, and the output terminal of the equipment controller 1e respectively controls the valve opening output 1c and closing output 1d according to the configuration.

The logic judgment B is implemented as follows: the logic judgment takes the valve opening as an example, and the air source pressure 2a at the end of the gas path and the air source pressure set value 2b are softly connected to the comparison module 2c; the valve opening output 1c and the valve timeout Set the time 2d for configuration soft connection. The valve timeout setting time 2d is the rising edge detection delay module in the control system; softly connect the valve opening feedback 1a with the inversion module 2e, and then set the valve timeout time The output of 2d and the inversion module 2e is logically judged by 2f and then logically judged with the output of 2c. After the judgment by 2g, the result is entered into the counting module 2h for accumulation.

Human-computer interaction interface monitoring C is implemented as follows: draw a table on the operation screen, the table content consists of valve opening 3a, valve opening feedback setting time 2d-1, valve opening feedback timeout times 2h-t and valve opening timeout times reset button 2h -r consists of four parts. Wherein, the valve opening feedback setting time 2d-1 is the same value as the setting time of 2d in logic judgment B. Valve opening feedback timeout times 2h-t and valve opening timeout times reset button 2h-r are two different functions of 2h in logic judgment B. Finally, the above parameter configuration is completed and released to the operator station before man-machine monitoring can be performed. operate.

Example 2

Embodiment 2 discloses a pneumatic valve fault prediction method based on the hardware of the valve fault prediction system in embodiment 1 and the logical judgment of the valve fault prediction system, including the following steps:

1) A valve feedback mechanism is installed on the pneumatic piston actuator of the pneumatic valve. The feedback mechanism is equipped with an open feedback detector and a close feedback detector; when the valve operates, the valve open/close feedback signal changes accordingly, and the detected The received signal is transmitted to the safety barrier through the control cable, and the safety barrier transmits the received signal to the digital input card in the DCS control system, and the open feedback and close feedback status information participates in the judgment in the configured logic.

2) Install a remote pressure transmitter at the end of the air path of the pneumatic valve, and transmit the collected pressure signal to the analog input card in the DCS control system through the safety barrier, AI card and other links, so that The collected pressure information participates in the judgment in the logic.

3) After the pneumatic valve is put into normal operation, after collecting the opening (closing) time of the valve, the judgment can be completed through the set time in the rising edge detection delay module in the logic judgment.

4) Under the condition that the pressure at the end of the air source is higher than the set pressure (the air source pressure is set according to the maximum air source pressure required by the on-site pneumatic piston actuator), when the valve opening signal command is issued, the detection logic starts Judgment, if the valve opening feedback status is not detected within the set time, the valve action has timed out, and the counting module starts counting once, indicating that the valve action is abnormal, and the valve needs to be repaired and maintained on site in time , otherwise, the valve action is normal, and the counting module does not count; when the air source pressure is lower than the set value, the fixed factor of the valve action has changed. According to the judgment logic, the valve is considered normal, and the counting module does not count at this time. count.

5) Set the monitoring interface on the human-computer interaction interface of the control terminal. The specific monitoring interface includes the valve opening (closing) feedback setting time, the valve opening (closing) feedback timeout times and the valve opening (closing) timeout times reset button. On the one hand, it is convenient for engineering and technical personnel to monitor and maintain in time, and at the same time, when the inherent characteristics of the valve change after a new valve is replaced, it is convenient to change the opening (closing) feedback setting time of the valve in time.

The present invention is based on the existing DCS control system, through the design of the hardware of the valve failure prediction system and the logic judgment of the valve failure prediction system. The process time is compared and judged with the system preset time range, and the timeout is recorded. The above-mentioned action time diagnosis mechanism can be set up for important position valves that are frequently used and frequently operated, which can predict the failure of the valve in advance, avoid the expansion of valve failure problems, and ensure that the function of the pneumatic valve as an important control component is normally put into use.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention. Inside.

Claims (7)

1. A pneumatic valve fault prediction system based on DCS control, characterized in that it includes a feedback mechanism, a pressure transmitter, a safety barrier, a terminal block, a DCS control system and an operation terminal, and the feedback mechanism is arranged on the pneumatic valve On the pneumatic piston actuator, the pressure transmitter is arranged at the end of the gas circuit of the pneumatic valve, the feedback mechanism and the pressure transmitter are electrically connected to the corresponding safety barrier, and the safety barrier is connected to the corresponding terminal Electrically connected, the terminal block is electrically connected to the DCS control system, and the DCS control system is electrically connected to the man-machine interface of the operation terminal. 2. The pneumatic valve fault prediction system based on DCS control according to claim 1, wherein the feedback mechanism includes open feedback and close feedback, and the open feedback and close feedback are respectively connected to the corresponding safety barrier through cables. Electrically connected, the safety barriers corresponding to the on-feedback and off-feedback are electrically connected to the same terminal. 3. The pneumatic valve fault prediction system based on DCS control according to claim 1 or 2, characterized in that, the terminal block corresponding to the feedback mechanism is connected to the DI card of the DCS control system through a cable, corresponding to the The terminal block of the pressure transmitter is connected to the AI card of the DCS control system through cables. 4. A method for predicting the failure of pneumatic valves based on DCS control, characterized in that, comprising the steps of: S1: Detect the on/off state of the pneumatic valve through the feedback mechanism, and transmit it to the corresponding safety barrier, and then transmit the on/off state feedback information received on the safety barrier to the corresponding configuration of the DCS control system On the DI card channel, perform remote receiving detection; S2: Detect the air source pressure at the end of the air path of the pneumatic valve through a pressure transmitter, and connect it to the DCS control system through a safety barrier, cable, and AI card to perform remote monitoring of the air source pressure; S3: Perform point information configuration in the DCS control system, and perform equipment control configuration according to the process interlock control situation; S4: After the pneumatic valve is put into normal operation, count and time the actual opening/closing action time of the pneumatic valve as the basis for its fault judgment setting value; S5: Design the judgment logic and set up the time parameters for the opening/closing process of the pneumatic valve. When the air source pressure at the end of the air circuit is normal, when the system issues a valve opening/closing command, the judgment logic starts timing judgment, such as the time when the pneumatic valve opening/closing feedback is in place When it is less than the set value, the alarm will not be triggered. If the pneumatic valve open/close feedback time is greater than the set value, the alarm will be triggered; S6: Set up alarm counting data, each time an alarm message occurs, the data is accumulated once; S7: Add an interface for alarm count data and fault judgment time parameters on the operation terminal. 5. The method for predicting failures of pneumatic valves based on DCS control according to claim 4, wherein the point information configured in step 3 includes valve opening feedback status, valve closing feedback status, valve opening command , Valve close command. 6. The method for predicting faults of pneumatic valves based on DCS control according to claim 4, characterized in that, if the gas source pressure at the end of the gas path in the step 5 is higher than the set pressure value, it is judged to be normal, so The pressure value set above is determined by the maximum air source pressure required by the pneumatic piston actuator in the pneumatic valve. 7. The DCS control-based pneumatic valve fault prediction method according to claim 4, characterized in that, in the step 7, functions of alarm counting data clearing and history query are added to the operation terminal.

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