Online diagnosis and compensation system for viscosity fault of regulating valve

Abstract

The invention relates to the technical field of regulating valve fault processing, in particular to a regulating valve viscosity fault online diagnosis and compensation system which comprises a circulation main line and a regulating valve, the circulation main line comprises an input port and an output port from left to right, and a monitoring mechanism used for monitoring the flow of the regulating valve is arranged on the circulation main line. A first three-way connector and a second three-way connector are installed at the left end and the right end of the circulation main line respectively. The flow main line is provided with the adjusting valve located in the middle position, so that whether the adjusting valve has a viscous fault or not is judged, the flow adjusting valve is arranged at the input port of the circulation main line, and the first three-way connector and the second three-way connector are symmetrically arranged at the left end and the right end of the circulation main line; and the flow on the circulation branch line is adjusted by installing the reversing valve, so that the flow difference of the circulation main line is made up.

Description

Technical Field

[0001] The invention relates to the technical field of regulating valve fault processing, and in particular to an online diagnosis and compensation system for a regulating valve sticking fault. Background Art

[0002] Control valves are the most commonly used actuators in industrial circuits, but due to aging and other problems, the friction between the seal and the valve stem is often too large, resulting in a sudden jump before the valve stem slides, which is called a sticking fault, causing the circuit to oscillate, thereby affecting product quality, system energy consumption, and factory profits. Since sticking faults are mainly caused by friction that causes the valve position of the actuator to be unable to change linearly according to the controller signal, the friction force, valve position signal, and controller output signal are important data that reflect sticking faults. At present, the devices and methods for obtaining the above data by changing the degree of sticking fault, that is, the friction force, through test devices are mostly too complicated. Therefore, how to effectively and controllably change the sticking fault degree of the control valve without damaging the actuator, and quickly and conveniently obtain important data that reflect sticking faults such as friction force, valve position signal, and controller output signal are the problems that need to be solved today.

[0003] Under existing conditions, a method for detecting the viscosity characteristic parameters of a control valve is adopted, such as that disclosed in announcement number CN107703761B, which converts the viscous nonlinear characteristics of the control valve into two parts, namely, known input and unknown input, in a linear manner, and uses field data to perform online estimation of the unknown input with the help of an unknown input estimator; then, a test signal is superimposed on the existing control signal to obtain estimation information, and then the nonlinear characteristics of the control valve are fitted using the estimation information. However, it is difficult to achieve dynamic monitoring of the control valve, and it is impossible to accurately judge the flow change by starting the control valve. In addition, the flow changes greatly with the change of distance and time, making it difficult to perform real-time adjustment, which can easily cause adverse effects on the flow out of control on the line where the control valve is installed. Summary of the invention

[0004] The purpose of the present invention is to solve the problem in the prior art that it is difficult to judge and repair whether a regulating valve has a sticking fault, and to propose an online diagnosis and compensation system for a sticking fault of a regulating valve.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: An online diagnosis and compensation system for a sticky fault of a regulating valve comprises a main circulation line and a regulating valve, wherein the main circulation line comprises an input port and an output port from left to right, and a monitoring mechanism for monitoring the flow of the regulating valve is arranged on the main circulation line, a first three-way joint and a second three-way joint are respectively installed at the left and right ends of the main circulation line, and a compensation mechanism for compensating the regulating valve is arranged on the main circulation line through the first three-way joint and the second three-way joint, the regulating valve is located in the middle of the main circulation line, the monitoring mechanism comprises a flow regulating valve installed at the input port, a first ultrasonic flow meter and a second ultrasonic flow meter are respectively installed at the left and right ends of the main circulation line, a time relay is connected between the first ultrasonic flow meter and the second ultrasonic flow meter through a first wire, and the time relay is connected to a PLC processor through a second wire.

[0006] In order to better achieve the above-mentioned purpose, the present invention adopts a further technical solution: the first ultrasonic flowmeter and the second ultrasonic flowmeter are symmetrically distributed on the left and right sides of the regulating valve.

[0007] In order to better achieve the above purpose, the present invention adopts a further technical solution: the first three-way connector and the second three-way connector are symmetrically distributed on the left and right ends of the main circulation line, and the first three-way connector is located between the flow regulating valve and the first ultrasonic flowmeter.

[0008] In order to better achieve the above-mentioned purpose, the present invention adopts a further technical solution: the compensation mechanism includes a circulation branch line connecting the first three-way connector and the second three-way connector, and a reversing valve is installed on the circulation branch line.

[0009] In order to better achieve the above purpose, the present invention adopts a further technical solution: the circulation branch line is divided into an access port and an outlet port from left to right, the access port is connected to a first three-way connector, and the outlet port is connected to a second three-way connector.

[0010] The advantages of the present invention are as follows: the present invention utilizes the main flow line to set a regulating valve located in the middle position, and sets a first ultrasonic flowmeter and a second ultrasonic flowmeter symmetrically on the left and right sides of the regulating valve, and sets a time relay between the first ultrasonic flowmeter and the second ultrasonic flowmeter to judge the flow change within a fixed distance, thereby judging whether the regulating valve has a sticking fault; a flow regulating valve is set at the input port of the main circulation line, and a first three-way joint and a second three-way joint are symmetrically set on the left and right ends of the main circulation line, so as to facilitate the setting of a circulation branch line bypassing the regulating valve, and the flow on the circulation branch line is adjusted by installing a reversing valve to compensate for the flow difference of the main circulation line. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1It is a structural schematic diagram of the online diagnosis and compensation system for the sticking fault of the regulating valve proposed by the present invention; Figure 2 This is a bottom view of the online diagnosis and compensation system for the sticking fault of the regulating valve proposed by the present invention.

[0012] In the figure: 1. main circulation line; 2. regulating valve; 3. input port; 4. output port; 5. flow regulating valve; 6. first ultrasonic flowmeter; 7. second ultrasonic flowmeter; 8. first wire; 9. time relay; 10. second wire; 11. PLC processor; 12. first three-way connector; 13. second three-way connector; 14. circulation branch line; 15. access port; 16. output port; 17. reversing valve. DETAILED DESCRIPTION

[0013] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0014] Reference Figure 1-Figure 2 As shown, the online diagnosis and compensation system for the sticking fault of the regulating valve includes a main circulation line 1 and a regulating valve 2. The main circulation line 1 is an input port 3 and an output port 4 from left to right. The regulating valve 2 is located in the middle of the main circulation line 1, so that the medium in the main circulation line 1 can pass through the regulating valve 2. A monitoring mechanism for monitoring the flow of the regulating valve 2 is provided on the main circulation line 1. The monitoring mechanism includes a flow regulating valve 5 installed at the position of the input port 3. The flow regulating valve 5 can adjust the flow by changing the opening of the valve or the throttling part to achieve the purpose of adjusting the flow rate. It is worth mentioning that there is no resistance between the valve structure of the flow control valve 5 and the flow through the pipeline, and the flow is relatively smooth, and the impact on the pipeline pressure is relatively small, so its performance is better than other flow rate regulating devices under high pressure difference, high viscosity and the like. The first ultrasonic flowmeter 6 and the second ultrasonic flowmeter 7 are respectively installed on the left and right ends of the main circulation line 1, and a time relay 9 is connected between the first ultrasonic flowmeter 6 and the second ultrasonic flowmeter 7 through a first wire 8, and the time relay 9 is connected to a PLC processor 11 through a second wire 10. It is worth mentioning that by monitoring the flow through the control valve 2 within a fixed distance and a limited time period, it is possible to determine whether the flow change is caused by the control valve 2.

[0015] A first three-way joint 12 and a second three-way joint 13 are respectively installed at the left and right ends of the main circulation line 1. The first three-way joint 12 and the second three-way joint 13 are symmetrically distributed on the left and right ends of the main circulation line 1, and the first three-way joint 12 is located between the flow regulating valve 5 and the first ultrasonic flowmeter 6.

[0016] The main circulation line 1 is provided with a compensation mechanism for compensating the flow of the regulating valve 2 through the first three-way joint 12 and the second three-way joint 13. The compensation mechanism includes a circulation branch line 14 connecting the first three-way joint 12 and the second three-way joint 13, and a reversing valve 17 is installed on the circulation branch line 14. After the PLC processor 11 determines that the flow on the main circulation line 1 has changed, the reversing valve 17 is opened to allow part of the medium at the input port 3 position to move to the output port 4 position through the circulation branch line 14. It is further explained that by adding a third ultrasonic flowmeter at the output port 4 position of the main circulation line 1, the flow after compensation can be monitored to ensure the accurate operation of the circulation branch line 14. The reversing valve 17 is a valve device that can change the flow direction of the fluid. The reversing valve 17 can adjust the flow rate by establishing one or more throttling ports, and can also change the inlet and outlet direction of the fluid to achieve more flexible fluid control.

[0017] The first ultrasonic flowmeter 6 and the second ultrasonic flowmeter 7 are symmetrically distributed on the left and right sides of the regulating valve 2 to facilitate flow monitoring of the medium passing through the regulating valve 2 .

[0018] The circulation branch line 14 is divided into an access port 15 and an outlet port 16 from left to right. The access port 15 is connected to the first three-way joint 12 , and the outlet port 16 is connected to the second three-way joint 13 , so that the medium can move in a directional manner through the circulation branch line 14 .

[0019] The specific models and specifications of the regulating valve 2, flow regulating valve 5, ultrasonic flowmeter, time relay 9, PLC processor 11, and reversing valve 17 need to be selected and determined according to the actual specifications of the device. The specific selection calculation method adopts the existing technology in this field, so it is not repeated here.

[0020] When the present invention is used, the medium is input into the circulation main line 1 through the input port 3 with the circulation branch line 14 closed, the flow rate of the medium before passing through the regulating valve 2 is recorded by the first ultrasonic flowmeter 6, and the flow rate of the medium after passing through the regulating valve 2 is recorded by the second ultrasonic flowmeter 7. It is determined whether there is a change in the flow rates before and after based on the duration recorded by the time relay 9. When the flow rate changes, the reversing valve 17 is controlled to open, so that part of the medium at the input port 3 of the circulation main line 1 moves to the output port 4 of the circulation main line 1 through the circulation branch line 14.

[0021] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An online diagnosis and compensation system for a sticking fault of a regulating valve, comprising a main circulation line (1) and a regulating valve (2), characterized in that: The main circulation line (1) comprises an input port (3) and an output port (4) from left to right, and a monitoring mechanism for monitoring the flow of the regulating valve (2) is arranged on the main circulation line (1). A first three-way joint (12) and a second three-way joint (13) are respectively installed at the left and right ends of the main circulation line (1), and a compensation mechanism for compensating the flow of the regulating valve (2) is arranged on the main circulation line (1) through the first three-way joint (12) and the second three-way joint (13). The regulating valve (2) is located in the middle of the main circulation line (1). The monitoring mechanism comprises a flow regulating valve (5) installed at the input port (3). A first ultrasonic flow meter (6) and a second ultrasonic flow meter (7) are respectively installed at the left and right ends of the main circulation line (1), and a time relay (9) is connected between the first ultrasonic flow meter (6) and the second ultrasonic flow meter (7) through a first wire (8), and the time relay (9) is connected to a PLC processor (11) through a second wire (10).

2. The online diagnosis and compensation system for the sticking fault of the regulating valve according to claim 1 is characterized in that: The first ultrasonic flow meter (6) and the second ultrasonic flow meter (7) are symmetrically distributed on the left and right sides of the regulating valve (2).

3. The online diagnosis and compensation system for the sticking fault of the regulating valve according to claim 1 is characterized in that: The first three-way connector (12) and the second three-way connector (13) are symmetrically distributed on the left and right ends of the main circulation line (1), and the first three-way connector (12) is located between the flow regulating valve (5) and the first ultrasonic flow meter (6).

4. The online diagnosis and compensation system for the sticking fault of the regulating valve according to claim 3 is characterized in that: The compensation mechanism comprises a circulation branch line (14) connecting the first three-way connector (12) and the second three-way connector (13), and a reversing valve (17) is installed on the circulation branch line (14).

5. The online diagnosis and compensation system for the sticking fault of the regulating valve according to claim 4 is characterized in that: The circulation branch line (14) is divided from left to right into an inlet port (15) and an outlet port (16), wherein the inlet port (15) is connected to a first three-way connector (12), and the outlet port (16) is connected to a second three-way connector (13).

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