Corrosive medium transportation pneumatic ball valve

Abstract

The utility model discloses a pneumatic ball valve for corrosive medium transportation, belongs to the technical field of corrosive medium transportation, and solves the problems that when a corrosive medium hinders a pneumatic actuator in the pneumatic ball valve to drive a valve ball, a conventional pneumatic ball valve always adopts a hard pulling mode to adjust the angle of the valve ball, and the service life of the valve ball is influenced. Therefore, the problem that the pneumatic ball valve is further damaged is solved. Comprising a valve body, a pneumatic actuator arranged on the valve body and a buzzer arranged on the valve body, the pneumatic actuator is coupled with a transmission fault detection circuit, and the output end of the transmission fault detection circuit is coupled with the input end of the buzzer. When the device works, the transmission fault detection circuit detects the current of the pneumatic actuator, after the current is converted, filtered, amplified and denoised, the differentiator extracts the change rate to generate a differential signal, the differential signal is converted into a holding voltage through double-peak detection, an alarm is triggered when the holding voltage exceeds a threshold value, the alarm circuit outputs a signal and controls the buzzer to give an alarm, and a torque time curve can be monitored in real time. And identifying the fault according to the current distortion.

Description

Technical Field

[0001] This utility model relates to the field of corrosive medium transportation technology, and in particular to a pneumatic ball valve for transporting corrosive media. Background Technology

[0002] Pneumatic ball valves are required for transporting corrosive media. A pneumatic ball valve consists of a ball, valve body, valve stem, and pneumatic actuator. During transport, the pneumatic actuator receives a signal and causes the ball to rotate, controlling the direction and flow rate of the media. It features good sealing performance, corrosion resistance, rapid opening and closing, remote control, and effectively prevents media leakage, ensuring transportation safety. It is commonly used in pipeline systems for transporting corrosive media in industries such as chemical and petroleum.

[0003] When a pneumatic ball valve is used to transport corrosive media, the corrosive media will directly erode the valve stem and transmission components, causing pitting or stress corrosion cracks on the valve stem surface. The corrosion products accumulate in the movement gap, increasing the frictional resistance. At the same time, the media will destroy the sealing packing and invade the bearing cavity, causing lubrication failure and corrosion of key transmission components such as gears and bearings. This will cause mechanical interference and a sharp drop in torque transmission efficiency, ultimately resulting in insufficient output torque of the pneumatic actuator to drive the valve ball, which manifests as valve action sticking, slow response, or even complete seizure.

[0004] However, when corrosive media obstruct the pneumatic actuator's drive of the ball in a pneumatic ball valve, conventional pneumatic ball valves often resort to a forced pull method to adjust the ball's angle, which can actually lead to further damage to the pneumatic ball valve.

[0005] Therefore, a pneumatic ball valve for transporting corrosive media is proposed to solve or alleviate the above problems. Utility Model Content

[0006] The purpose of this utility model is to address the shortcomings of existing technologies by proposing a pneumatic ball valve for transporting corrosive media.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A pneumatic ball valve for transporting corrosive media includes a valve body, a pneumatic actuator mounted on the valve body, and a buzzer mounted on the valve body. The pneumatic actuator is coupled to a transmission fault detection circuit. The output terminal of the transmission fault detection circuit is coupled to the input terminal of the buzzer. The transmission fault detection circuit monitors the drive current of the pneumatic actuator in real time and extracts the current change rate characteristics. When it identifies a double-peak distorted waveform caused by corrosion jamming, it maintains the circuit's accumulated voltage signal and controls the buzzer to work.

[0009] Preferably, the transmission fault detection circuit includes a current detection circuit, a waveform shaping circuit, a differentiator circuit, a dual-peak detection circuit, a threshold comparison circuit, and an alarm output circuit. The output terminal of the current detection circuit is connected to the input terminal of the waveform shaping circuit, the output terminal of the waveform shaping circuit is connected to the input terminal of the differentiator circuit, the output terminal of the differentiator circuit is connected to the input terminal of the dual-peak detection circuit, the output terminal of the dual-peak detection circuit is connected to the non-inverting input terminal of the threshold comparison circuit, the output terminal of the threshold comparison circuit is connected to the control terminal of the alarm output circuit, and the execution terminal of the alarm output circuit is connected to a buzzer.

[0010] Preferably, the current detection circuit includes a current transformer, a first resistor, and a first capacitor. The primary coil of the current transformer is connected in series in the positive power line of the pneumatic actuator. One end of the secondary coil of the current transformer is grounded, and the other end of the secondary coil of the current transformer is connected to one end of the first resistor. The other end of the first resistor is connected to one end of the first capacitor and the input terminal of the waveform shaping circuit. The other end of the first capacitor is grounded.

[0011] Preferably, the waveform shaping circuit includes a first operational amplifier, a second resistor, and a third resistor. The non-inverting input of the first operational amplifier is connected to the output of the current detection circuit. The inverting input of the first operational amplifier is grounded through the second resistor. The inverting input of the first operational amplifier is connected to its output through the third resistor. The power supply terminal of the first operational amplifier is connected to power.

[0012] Preferably, the differentiator circuit includes a second operational amplifier, a second capacitor, a fourth resistor, a fifth resistor, and a first potentiometer. The inverting input terminal of the second operational amplifier is connected to the output terminal of the waveform shaping circuit through the second capacitor. The inverting input terminal of the second operational amplifier is connected to the output terminal of the second operational amplifier through the fourth resistor. The non-inverting input terminal of the second operational amplifier is grounded through the fifth resistor. The first fixed terminal of the first potentiometer is energized, the second fixed terminal of the first potentiometer is grounded, and the sliding terminal of the first potentiometer is connected to the end of the fourth resistor away from the inverting input terminal of the second operational amplifier.

[0013] Preferably, the dual-peak detection circuit includes a first diode, a third capacitor, a second diode, and a sixth resistor. The anode of the first diode is connected to the output terminal of the differentiator circuit, the cathode of the first diode is connected to the positive terminal of the third capacitor, the negative terminal of the third capacitor is grounded, the sixth resistor is connected in parallel across the three terminals of the third capacitor, the anode of the second diode is connected to the positive terminal of the third capacitor, and the cathode of the second diode serves as the output terminal of the dual-peak detection circuit.

[0014] Preferably, the threshold comparison circuit includes an LM393 voltage comparator, a second potentiometer, a seventh resistor, and an eighth resistor. The non-inverting input of the LM393 voltage comparator is connected to the output of the dual-peak detection circuit through the seventh resistor. The inverting input of the LM393 voltage comparator is connected to the sliding terminal of the second potentiometer. The first fixed terminal of the second potentiometer is energized, and the second fixed terminal of the second potentiometer is grounded. The output of the LM393 voltage comparator is connected to the power supply through the eighth resistor.

[0015] Preferably, the alarm output circuit includes an NPN transistor, a ninth resistor, and a fourth capacitor. The base of the NPN transistor is connected to the output terminal of the threshold comparison circuit through the ninth resistor. The emitter of the NPN transistor is grounded. The collector of the NPN transistor is connected to the positive terminal of the buzzer. The negative terminal of the buzzer is grounded. The positive terminal of the fourth capacitor is connected to the collector of the NPN transistor. The negative terminal of the fourth capacitor is grounded.

[0016] This utility model has the following beneficial effects:

[0017] When this utility model is working, the transmission fault detection circuit detects the current of the pneumatic actuator. After the current is converted, filtered, amplified and denoised, the differentiator extracts the rate of change to generate a differential signal. The dual-peak detection is converted into a holding voltage. When the threshold is exceeded, an alarm is triggered. The alarm circuit outputs a signal and controls the buzzer to sound an alarm. The torque-time curve can be monitored in real time, and the fault can be identified based on the current distortion. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of this utility model;

[0020] Figure 2 This is a structural block diagram of the transmission fault detection circuit in this utility model.

[0021] In the diagram: 1. Valve body; 2. Pneumatic actuator; 3. Current detection circuit; 4. Waveform shaping circuit; 5. Differentiator circuit; 6. Dual-peak detection circuit; 7. Threshold comparison circuit; 8. Alarm output circuit. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0024] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0025] In the description of this utility model, it should be understood that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only used to facilitate the description of this utility model and to simplify the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0026] Furthermore, the terms "first," "second," and "third" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0027] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0028] A pneumatic ball valve for transporting corrosive media, such as Figure 1As shown, the device includes a valve body 1, a pneumatic actuator 2 mounted on the valve body 1, and a buzzer mounted on the valve body 1. The pneumatic actuator 2 is coupled to a transmission fault detection circuit. The output terminal of the transmission fault detection circuit is coupled to the input terminal of the buzzer. The transmission fault detection circuit monitors the drive current of the pneumatic actuator 2 in real time and extracts the current change rate characteristics. When it identifies a double-peak distorted waveform caused by corrosion jamming, it maintains the circuit's accumulated voltage signal and controls the buzzer to work.

[0029] like Figure 2 As shown, the transmission fault detection circuit includes a current detection circuit 3, a waveform shaping circuit 4, a differentiator circuit 5, a dual-peak detection circuit 6, a threshold comparison circuit 7, and an alarm output circuit 8. The output terminal of the current detection circuit 3 is connected to the input terminal of the waveform shaping circuit 4, the output terminal of the waveform shaping circuit 4 is connected to the input terminal of the differentiator circuit 5, the output terminal of the differentiator circuit 5 is connected to the input terminal of the dual-peak detection circuit 6, the output terminal of the dual-peak detection circuit 6 is connected to the non-inverting input terminal of the threshold comparison circuit 7, the output terminal of the threshold comparison circuit 7 is connected to the control terminal of the alarm output circuit 8, and the execution terminal of the alarm output circuit 8 is connected to the buzzer.

[0030] The current detection circuit 3 includes a current transformer, a first resistor, and a first capacitor. The primary coil of the current transformer is connected in series in the positive power line of the pneumatic actuator 2. One end of the secondary coil of the current transformer is grounded, and the other end of the secondary coil of the current transformer is connected to one end of the first resistor. The other end of the first resistor is connected to one end of the first capacitor and the input terminal of the waveform shaping circuit 4. The other end of the first capacitor is grounded.

[0031] The waveform shaping circuit 4 includes a first operational amplifier, a second resistor, and a third resistor. The non-inverting input of the first operational amplifier is connected to the output of the current detection circuit 3. The inverting input of the first operational amplifier is grounded through the second resistor. The inverting input of the first operational amplifier is connected to its output through the third resistor. The power supply of the first operational amplifier is connected to the power supply.

[0032] The differentiator circuit 5 includes a second operational amplifier, a second capacitor, a fourth resistor, a fifth resistor, and a first potentiometer. The inverting input terminal of the second operational amplifier is connected to the output terminal of the waveform shaping circuit 4 through the second capacitor. The inverting input terminal of the second operational amplifier is connected to the output terminal of the second operational amplifier through the fourth resistor. The non-inverting input terminal of the second operational amplifier is grounded through the fifth resistor. The first fixed terminal of the first potentiometer is energized, the second fixed terminal of the first potentiometer is grounded, and the sliding terminal of the first potentiometer is connected to the end of the fourth resistor away from the inverting input terminal of the second operational amplifier.

[0033] The first operational amplifier and the second operational amplifier are actually two operational amplifiers in the LM358 operational amplifier.

[0034] The dual-peak detection circuit 6 includes a first diode, a third capacitor, a second diode, and a sixth resistor. The anode of the first diode is connected to the output terminal of the differentiator circuit 5, the cathode of the first diode is connected to the positive terminal of the third capacitor, the negative terminal of the third capacitor is grounded, the sixth resistor is connected in parallel across the three terminals of the third capacitor, the anode of the second diode is connected to the positive terminal of the third capacitor, and the cathode of the second diode serves as the output terminal of the dual-peak detection circuit 6.

[0035] The threshold comparison circuit 7 includes an LM393 voltage comparator, a second potentiometer, a seventh resistor, and an eighth resistor. The non-inverting input of the LM393 voltage comparator is connected to the output of the dual-peak detection circuit 6 through the seventh resistor. The inverting input of the LM393 voltage comparator is connected to the sliding terminal of the second potentiometer. The first fixed terminal of the second potentiometer is energized, and the second fixed terminal of the second potentiometer is grounded. The output of the LM393 voltage comparator is connected to the power supply through the eighth resistor.

[0036] The alarm output circuit 8 includes an NPN transistor, a ninth resistor, and a fourth capacitor. The base of the NPN transistor is connected to the output of the threshold comparison circuit 7 through the ninth resistor. The emitter of the NPN transistor is grounded. The collector of the NPN transistor is connected to the positive terminal of the buzzer. The negative terminal of the buzzer is grounded. The positive terminal of the fourth capacitor is connected to the collector of the NPN transistor. The negative terminal of the fourth capacitor is grounded.

[0037] When this invention is in operation, the transmission fault detection circuit can function to detect the drive current of the pneumatic actuator 2. Specifically, the current detection circuit 3 converts the operating current of the pneumatic actuator 2 into a voltage signal and performs primary filtering. Then, the waveform shaping circuit 4 amplifies the voltage signal and filters out high-frequency noise. Next, the differentiator circuit 5 extracts the rate of change of current and generates a differential signal related to the transmission resistance. The double-peak detection circuit 6 captures the double-peak characteristics in the differential signal and converts it into a holding voltage. Finally, the threshold comparison circuit 7 triggers an alarm when the holding voltage exceeds a set threshold. Finally, the alarm output circuit 8 outputs a fault indication signal and controls a buzzer to sound an alarm. This allows the transmission fault detection circuit to monitor the torque-time characteristic curve of the pneumatic actuator 2 driving the valve ball in real time. When corrosion causes an increase in transmission resistance, the fault is identified through current waveform distortion, triggering an alarm.

[0038] Specifically, when the transmission fault detection circuit is working,

[0039] The primary coil of the current transformer is connected in series to the positive power supply line of the pneumatic actuator 2. When the pneumatic actuator 2 drives the valve ball to rotate, the working current flows through the primary coil of the current transformer, and a proportional current signal is induced in the secondary coil of the current transformer. This secondary current passes through a low-pass filter network composed of a first resistor and a first capacitor connected in parallel, converting the current signal into a 0-1V voltage signal and filtering out high-frequency interference.

[0040] The voltage signal is input to the non-inverting input terminal of the first operational amplifier of the waveform shaping circuit 4. The non-inverting amplifier formed by the first operational amplifier processes the signal and generates an amplified signal of 0-2V at the output terminal. At the same time, the signal jitter is eliminated through internal negative feedback, forming a smooth trapezoidal voltage waveform.

[0041] The amplified signal is coupled to the inverting input of the second operational amplifier in the differentiator circuit 5 through the second capacitor C3. The second operational amplifier and the fourth resistor R5 constitute the core circuit of the differentiator. Its transfer function is V_out = -R5×C3×d(V_in) / dt. This transfer function is existing technology and does not involve any improvement. It converts the rate of change of current into voltage pulses.

[0042] When the pneumatic ball valve starts normally, the current rises at a constant speed, and the second operational amplifier outputs a single positive pulse. If the transmission is stuck due to corrosion, the pneumatic actuator 2 will encounter a sudden increase in resistance after starting, and the current will show a double-peak characteristic of "rise-brief drop-second climb". The second operational amplifier will output double positive pulses with an interval of about 200ms. This pulse sequence is input to the double-peak detection circuit 6. The first diode conducts to the positive pulse and charges the third capacitor.

[0043] Under normal single pulse conditions, the voltage of the third capacitor C4 is slowly discharged through the sixth resistor and cannot reach the threshold. However, when a double pulse occurs, the second pulse charges the third capacitor again within 300ms, causing the voltage to be superimposed to above 2V.

[0044] The voltage is input to the non-inverting input of the LM393 voltage comparator in threshold comparison circuit 7 through the seventh resistor. The inverting input of the LM393 voltage comparator is connected to the sliding terminal of the second potentiometer, with a preset threshold of 1.5V. When the voltage of the third capacitor exceeds the threshold, the output of the LM393 voltage comparator changes from low to high. This signal drives the NPN transistor in alarm output circuit 8 to conduct through the ninth resistor. The collector current of the NPN transistor simultaneously activates the buzzer. The fourth capacitor connected in parallel suppresses transient interference from the switch.

[0045] The alarm state will continue until the voltage of the third capacitor is discharged below the threshold through the sixth resistor, while the cathode of the third diode is connected to the positive terminal of the third capacitor to prevent the capacitor from breaking down in reverse.

[0046] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A pneumatic ball valve for transporting corrosive media, characterized in that, It includes a valve body (1), a pneumatic actuator (2) mounted on the valve body (1), and a buzzer mounted on the valve body (1). The pneumatic actuator (2) is coupled to a transmission fault detection circuit. The output terminal of the transmission fault detection circuit is coupled to the input terminal of the buzzer. The transmission fault detection circuit monitors the drive current of the pneumatic actuator (2) in real time and extracts the current change rate characteristics. When it identifies a double-peak distorted waveform caused by corrosion jamming, it maintains the circuit's accumulated voltage signal and controls the buzzer to work.

2. The pneumatic ball valve for transporting corrosive media according to claim 1, characterized in that, The transmission fault detection circuit includes a current detection circuit (3), a waveform shaping circuit (4), a differentiator circuit (5), a double-peak detection circuit (6), a threshold comparison circuit (7), and an alarm output circuit (8). The output terminal of the current detection circuit (3) is connected to the input terminal of the waveform shaping circuit (4). The output terminal of the waveform shaping circuit (4) is connected to the input terminal of the differentiator circuit (5). The output terminal of the differentiator circuit (5) is connected to the input terminal of the double-peak detection circuit (6). The output terminal of the double-peak detection circuit (6) is connected to the in-phase input terminal of the threshold comparison circuit (7). The output terminal of the threshold comparison circuit (7) is connected to the control terminal of the alarm output circuit (8). The execution terminal of the alarm output circuit (8) is connected to a buzzer.

3. The pneumatic ball valve for transporting corrosive media according to claim 2, characterized in that, The current detection circuit (3) includes a current transformer, a first resistor, and a first capacitor. The primary coil of the current transformer is connected in series in the positive power line of the pneumatic actuator (2). One end of the secondary coil of the current transformer is grounded, and the other end of the secondary coil of the current transformer is connected to one end of the first resistor. The other end of the first resistor is connected to one end of the first capacitor and the input terminal of the waveform shaping circuit (4). The other end of the first capacitor is grounded.

4. The pneumatic ball valve for transporting corrosive media according to claim 2, characterized in that, The waveform shaping circuit (4) includes a first operational amplifier, a second resistor, and a third resistor. The non-inverting input of the first operational amplifier is connected to the output of the current detection circuit (3). The inverting input of the first operational amplifier is grounded through the second resistor. The inverting input of the first operational amplifier is connected to its output through the third resistor. The power supply of the first operational amplifier is connected to the power supply.

5. A pneumatic ball valve for transporting corrosive media according to claim 2, characterized in that, The differentiator circuit (5) includes a second operational amplifier, a second capacitor, a fourth resistor, a fifth resistor, and a first potentiometer. The inverting input terminal of the second operational amplifier is connected to the output terminal of the waveform shaping circuit (4) through the second capacitor. The inverting input terminal of the second operational amplifier is connected to the output terminal of the second operational amplifier through the fourth resistor. The non-inverting input terminal of the second operational amplifier is grounded through the fifth resistor. The first fixed terminal of the first potentiometer is energized, the second fixed terminal of the first potentiometer is grounded, and the sliding terminal of the first potentiometer is connected to the end of the fourth resistor away from the inverting input terminal of the second operational amplifier.

6. The pneumatic ball valve for transporting corrosive media according to claim 2, characterized in that, The dual-peak detection circuit (6) includes a first diode, a third capacitor, a second diode, and a sixth resistor. The anode of the first diode is connected to the output terminal of the differentiator circuit (5), the cathode of the first diode is connected to the positive terminal of the third capacitor, the negative terminal of the third capacitor is grounded, the sixth resistor is connected in parallel across the two ends of the third capacitor, the anode of the second diode is connected to the positive terminal of the third capacitor, and the cathode of the second diode serves as the output terminal of the dual-peak detection circuit (6).

7. A pneumatic ball valve for transporting corrosive media according to claim 2, characterized in that, The threshold comparison circuit (7) includes an LM393 voltage comparator, a second potentiometer, a seventh resistor, and an eighth resistor. The non-inverting input of the LM393 voltage comparator is connected to the output of the dual-peak detection circuit (6) through the seventh resistor. The inverting input of the LM393 voltage comparator is connected to the sliding terminal of the second potentiometer. The first fixed terminal of the second potentiometer is energized, and the second fixed terminal of the second potentiometer is grounded. The output of the LM393 voltage comparator is connected to the power supply through the eighth resistor.

8. A pneumatic ball valve for transporting corrosive media according to claim 2, characterized in that, The alarm output circuit (8) includes an NPN transistor, a ninth resistor, and a fourth capacitor. The base of the NPN transistor is connected to the output terminal of the threshold comparison circuit (7) through the ninth resistor. The emitter of the NPN transistor is grounded. The collector of the NPN transistor is connected to the positive terminal of the buzzer. The negative terminal of the buzzer is grounded. The positive terminal of the fourth capacitor is connected to the collector of the NPN transistor. The negative terminal of the fourth capacitor is grounded.

Images