A butterfly valve shaft axial seal test system and test method

Abstract

The present invention discloses a butterfly valve shaft axial seal test system and a test method thereof, wherein a first pneumatic butterfly valve, an environmental simulation component, a sensor component, and a second pneumatic butterfly valve are sequentially arranged on a main pipe, a gas generating device is connected to the main pipe via a first pneumatic three-way ball valve, and a polluted gas treatment device is connected to the main pipe via a second pneumatic three-way ball valve. The first pneumatic butterfly valve and the second pneumatic butterfly valve are both axially provided with an axial seal component and an axial seal cover sleeved outside the axial seal component, a first smoke sensor is arranged inside the axial seal cover, and the first smoke sensor is connected to a central controller signal. An axial seal cover is installed outside the axial seal component to form a closed space, in which a first smoke sensor is installed to detect the concentration of particulate matter to judge the axial sealability of the valve shaft, and the entire system only needs to prepare the test gas once to test the sealability under different temperatures and pressures, which is more energy-efficient and reduces costs.

Description

Technical Field

[0001] The invention relates to a butterfly valve shaft axial sealing test system and a test method thereof, belonging to the technical field of sealing test. Background Art

[0002] STC pneumatic butterfly valve is a key component for controlling the inlet and exhaust pipelines of the ship diesel engine sequential supercharging system. Its operating temperature is as high as 650℃ and the pressure is as high as 4 kg. The gas flowing through the pipeline is the high-temperature toxic exhaust gas produced by the combustion of the ship engine. When the butterfly valve has poor sealing performance and causes exhaust gas leakage, the increased gas concentration in the cabin is likely to cause poisoning or explosion, which seriously endangers safety.

[0003] The axial seal of the valve shaft of the pneumatic butterfly valve in the STC system of the marine engine is very important. First of all, the ship's exhaust system must be able to effectively discharge the exhaust gas generated by combustion while preventing external air from entering the system. The presence of the valve shaft axial seal helps prevent uncontrolled gas leakage during the exhaust process and ensures that the system can maintain appropriate working pressure and air tightness.

[0004] Secondly, the axial sealing of the valve shaft helps maintain the precise control of the pneumatic butterfly valve. The performance of the ship's exhaust system is affected by many factors such as engine load, ship speed and environmental conditions. By maintaining the axial sealing of the valve shaft, it can ensure that the pneumatic butterfly valve can maintain accurate control under different operating conditions, so that the exhaust system can effectively adapt to various navigation conditions.

[0005] In addition, valve shaft axial sealing can also help reduce energy waste. If there is a leak in the exhaust system, it will lead to energy loss because the system cannot effectively discharge the exhaust gas from the engine to the external environment. By maintaining the valve shaft axial sealing, energy waste can be minimized and the energy efficiency of the exhaust system can be improved.

[0006] When testing the axial sealing performance of the valve shaft, if the engine is directly used as the gas generating equipment for high-temperature sealing test, the cost is high and the gas utilization rate is low. When the gas flow rate in the pipeline is too slow during the test, the engine is prone to surge, affecting the accuracy of the test results. In addition, the sealing test requires testing multiple sets of data under a variety of different temperature and pressure conditions, while the engine is usually set under a fixed working cycle, which cannot meet the actual test needs. Summary of the invention

[0007] Purpose of the invention: In view of the deficiencies in the prior art, the present invention provides a butterfly valve shaft axial sealing test system and a test method thereof. The present invention tests the axial sealing of the butterfly valve shaft by setting up a sealing test system, thereby compensating for the problems of high engine cost and low gas utilization.

[0008] Technical solution: A butterfly valve shaft axial seal test system, comprising a gas generating device, a first pneumatic three-way ball valve, a second pneumatic three-way ball valve, a polluted gas treatment device, a first pneumatic butterfly valve, a second pneumatic butterfly valve, a sensor assembly and an environmental simulation assembly, which are respectively connected to a central controller by signals. The first pneumatic butterfly valve, the environmental simulation assembly, the sensor assembly and the second pneumatic butterfly valve are sequentially arranged on the main pipe. The gas generating device is connected to the main pipe through the first pneumatic three-way ball valve, and the polluted gas treatment device is connected to the main pipe through the second pneumatic three-way ball valve. The first pneumatic butterfly valve and the second pneumatic butterfly valve are both axially installed with an axial sealing assembly and an axial sealing cover sleeved on the outside of the axial sealing assembly. A first smoke sensor is arranged in the axial sealing cover, and the first smoke sensor is connected to the central controller by signal.

[0009] The present invention sets the first pneumatic butterfly valve, the environmental simulation component, the sensor component, and the second pneumatic butterfly valve as a test pipeline, generates test gas through a gas generator, discharges the air in the pipe or processes the test gas through a polluted gas treatment device, controls the environmental simulation component to make the test pipeline a high-temperature and high-pressure working condition, and in order to measure the axial sealing performance of the butterfly valve shaft, if the test gas leaks from the axial sealing component to the axial sealing cover, the first smoke sensor detects whether the ambient particulate matter concentration exceeds the standard value of 35μg / m 3 If it exceeds the limit, it means that the sealing performance of the axial sealing assembly is poor and needs to be replaced in time, which solves the expensive problem when the engine is directly used as a test gas generating device. The temperature and pressure of the test gas can be adjusted through the environmental simulation assembly, and the sealing performance at different temperatures and pressures can be tested. The test gas can be recycled, saving costs and shortening test time.

[0010] Preferably, in order to monitor the temperature and pressure of the test gas in the tube in real time, the sensor assembly includes a temperature sensor and a pressure sensor respectively connected to the central controller. By setting the temperature sensor and the pressure sensor, the temperature and pressure values ​​of the test gas are sent to the central controller in real time, thereby improving the accuracy of the test and facilitating the subsequent adjustment of the temperature and pressure values.

[0011] Preferably, in order to test the sealing performance under different temperatures and pressures, the environmental simulation component includes a gas heating device and a pressure regulating device connected to each other, and the gas heating device and the pressure regulating device are respectively connected to the central controller by signal. The temperature sensor and the pressure sensor transmit the current temperature value and pressure value to the central controller, and the central controller controls the gas heating device and the pressure regulating device to adjust to the corresponding temperature and pressure respectively according to the temperature value and pressure value to measure the axial sealing performance, and makes real-time adjustments according to the parameter changes to improve the accuracy of the test results.

[0012] Preferably, in order to adjust the pressure value, the pressure regulating device includes an air chamber, a push rod, and an electric cylinder, wherein the push rod is connected to the electric cylinder and moves in the air chamber, and the electric cylinder is connected to the central controller signal. The central controller receives the pressure value signal transmitted by the pressure sensor, and determines whether the pressure value is too large or too small. If the pressure value is too large, the push rod is driven by the electric cylinder to move in a direction close to the electric cylinder to release the pressure. If the pressure value is too small, the push rod is driven in a direction away from the electric cylinder to compress, thereby adjusting the pressure value and achieving the purpose of testing the sealing performance at different pressures.

[0013] Preferably, in order to control the flow of the test gas, a flow control assembly is provided between the gas generating device and the first pneumatic butterfly valve, the flow control assembly comprising a flow proportional valve and a proportional valve controller connected to each other, the proportional valve controller being connected to the central controller by signal. The central controller controls the proportional valve controller to adjust the opening of the flow proportional valve to control the flow of the test gas when it enters.

[0014] Preferably, in order to recycle the test gas, a gas cooling device is provided between the second pneumatic butterfly valve and the contaminated gas treatment device, and the gas cooling device is connected to the central controller. The test gas is cooled by the gas cooling device and then heated by the gas heating device, which can improve the accuracy of temperature control, and after the test is completed, the gas cooling device is used again to cool the test gas in the tube before discharging it, which can better protect the environment.

[0015] Preferably, in order to seal the first pneumatic butterfly valve and the second pneumatic butterfly valve, the first pneumatic butterfly valve and the second pneumatic butterfly valve both include a valve shaft and a valve body, and the axial sealing assembly includes a spacer sleeve, an axial sealing sleeve, a pre-tightening pressure sleeve, and a pre-tightening gland sequentially installed on the valve shaft, and the pre-tightening gland is bolted to the valve body. By bolting the pre-tightening gland to the valve body, the spacer sleeve, the axial sealing sleeve, the pre-tightening pressure sleeve, and the pre-tightening gland are in close contact to ensure sealing.

[0016] Preferably, in order to improve the sealing performance, a butterfly spring is provided between the pre-tightening gland and the valve body. Since the upper surface of the pre-tightening gland is uneven during the manufacturing process, the bolt cannot completely contact the upper surface of the pre-tightening gland, and there will be a gap, which reduces the sealing performance. Therefore, a butterfly spring is provided between the bolt and the pre-tightening gland. When the bolt is tightened, the butterfly spring will deform to fill the gap between the two, ensuring the tightness of the connection and the axial sealing performance.

[0017] Preferably, in order to detect whether the air in the pipe is completely discharged, a second smoke sensor is provided near the inlet end of the polluted gas treatment device, and the second smoke sensor is connected to the central controller by signal. The second smoke sensor detects the concentration of ambient particles in the pipe to determine whether the air in the pipe is completely discharged. If the concentration of ambient particles changes significantly and tends to be stable, it means that the air in the pipe has been completely discharged.

[0018] A method for testing a butterfly valve shaft axial seal test system, comprising the following steps:

[0019] Step 1: Test preparation: Open the first pneumatic three-way ball valve and the second pneumatic three-way ball valve, and open the first pneumatic butterfly valve and the second pneumatic butterfly valve, and disconnect the connection between the gas generating device and the polluted gas treatment device through the first pneumatic three-way ball valve or the second pneumatic three-way ball valve;

[0020] Step 2: Exhaust the air in the pipe: Start the gas generator to generate test gas, and turn on the polluted gas treatment device, exhaust all the air in the original system through the polluted gas treatment device, adjust the gas flow rate through the flow proportional valve, and judge whether the test gas fills the entire system loop through the ambient particle concentration detected by the second smoke sensor. If the ambient particle concentration increases and tends to be stable, that is, the test gas has filled the loop, then go to step 3; otherwise, continue to exhaust the air; then disconnect the gas generator and the polluted gas treatment device from the main pipeline through the first pneumatic three-way ball valve and the second pneumatic three-way ball valve, so that the test gas circulates in the main pipeline;

[0021] Step 3: Simulate the working environment: close the first pneumatic butterfly valve and the second pneumatic butterfly valve, as well as the gas generating device and the polluted gas processing device, and allow the test gas to flow between the first pneumatic butterfly valve and the second pneumatic butterfly valve. Start the gas heating device and the pressure regulating device, and adjust the test gas temperature and the pressure in the pipe to meet the working environment.

[0022] Step 4: Determine the axial sealing performance: The first smoke sensor detects the change of the concentration of ambient particulate matter in the axial sealing cover over time. If the concentration is less than the standard value, the sealing performance is qualified; if it is greater than the standard value, the sealing performance is unqualified and the axial sealing assembly needs to be replaced in time.

[0023] Step 5: Cooling and recycling: turn off the gas heating device and the pressure regulating device, turn on the gas cooling device, and first open the second pneumatic butterfly valve to allow the test gas to enter the gas cooling device due to the pressure difference, then open the first pneumatic butterfly valve to allow the test gas to circulate and cool in the tube, then return to step 3 to complete the sealing test at different temperatures and pressures, and after the test is completed, proceed to step 6;

[0024] Step six: Exhaust the test gas: turn off the gas cooling device, connect the gas generating device and the polluted gas treatment device to the main pipeline through the first pneumatic three-way ball valve and the second pneumatic three-way ball valve, and connect the gas generating device and the polluted gas treatment device. At this time, the gas generating device only transmits outside air and does not generate test gas. Open the polluted gas treatment device to exhaust the test gas.

[0025] The present invention first discharges the air in the pipe, and after the main pipe is filled with test gas, disconnects the gas generating device and the polluted gas treatment device from the main pipe to allow the test gas to circulate in the main pipe, and then closes the first pneumatic butterfly valve and the second pneumatic butterfly valve to adjust the temperature and pressure of the test gas therebetween. After the test is completed, the first pneumatic butterfly valve and the second pneumatic butterfly valve and the gas cooling device are opened again to circulate and cool the test gas in the pipe to prepare gas for the next test, thereby improving the accuracy of temperature control and compensating for the gas lost in the test area. After the test is completed, the test gas is discharged through the gas cooling device and the polluted gas treatment device. The entire system only needs to prepare the test gas once, and can test the sealing performance under different temperatures and pressures. At the same time, it is more energy-efficient and reduces costs.

[0026] Beneficial effects: The present invention arranges the first pneumatic butterfly valve, the environmental simulation component, the sensor component, and the second pneumatic butterfly valve in sequence on the main pipeline to form a circulation pipeline, and an external gas generating device and a polluted gas treatment device are connected to improve the utilization rate of the gas. The entire system only needs to prepare the test gas once to test the sealing performance under different temperatures and pressures, which is more energy-saving and reduces costs. An axial sealing cover is installed on the outside of the axial sealing component to form an enclosed space. A first smoke sensor is installed in it to detect the concentration of particulate matter to determine the axial sealing performance of the valve shaft. At the same time, a pressure sensor and a temperature sensor are configured to control the gas heating device and the pressure regulating device, and a gas cooling device is provided to ensure the accuracy of the test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0028] Figure 1 This is a structural diagram of the valve shaft axial seal of the present invention;

[0029] Figure 2 It is a structural diagram of the sealing system of the present invention;

[0030] Figure 3 is a flow chart of the testing method of the present invention;

[0031] Figure 4 It is a process diagram of the testing method of the present invention. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] In the description of the present invention, it is necessary to understand that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0034] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0035] like Figure 1 and Figure 2As shown, a butterfly valve shaft axial seal test system includes a gas generating device 2, a first pneumatic three-way ball valve 3, a second pneumatic three-way ball valve 4, a polluted gas treatment device 5, a first pneumatic butterfly valve 6, a second pneumatic butterfly valve 7, a sensor assembly 8 and an environmental simulation assembly 9, which are respectively connected to a central controller 1 by signals. The first pneumatic butterfly valve 6, the environmental simulation assembly 9, the sensor assembly 8 and the second pneumatic butterfly valve 7 are sequentially arranged on the main pipe. The gas generating device 2 is connected to the main pipe through the first pneumatic three-way ball valve 3, and the polluted gas treatment device 5 is connected to the main pipe through the second pneumatic three-way ball valve 4. The first pneumatic butterfly valve 6 and the second pneumatic butterfly valve 7 are both axially installed with an axial sealing assembly 10 and an axial sealing cover 11 sleeved on the outside of the axial sealing assembly 10. A first smoke sensor 12 is arranged in the axial sealing cover 11, and the first smoke sensor 12 is connected to the central controller 1 by signals.

[0036] The first pneumatic butterfly valve 6, the environmental simulation component 9, the sensor component 8, and the second pneumatic butterfly valve 7 are set as a test pipeline. The test gas is generated by the gas generator 2. The air in the pipe is discharged or the test gas is processed by the polluted gas treatment device 5. The environmental simulation component 9 is controlled to make the test pipeline a high temperature and high pressure condition. In order to measure the axial sealing performance of the butterfly valve shaft 61, if the test gas leaks from the axial sealing component 10 to the axial sealing cover 11, the first smoke sensor 12 detects whether the ambient particulate matter concentration exceeds the standard value of 35μg / m 3 If it exceeds, it means that the sealing performance of the axial sealing component 10 is poor and needs to be replaced in time, which solves the high cost problem when the engine is directly used as a test gas generating device. The temperature and pressure of the test gas can be adjusted through the environmental simulation component 9, and the sealing performance at different temperatures and pressures can be tested. The test gas can be recycled, saving costs and shortening the test time. At the same time, the pneumatic actuators of the first pneumatic butterfly valve 6 and the second pneumatic butterfly valve 7 are equipped with travel switch limiters to limit the flow direction of the pipeline gas.

[0037] In order to monitor the temperature and pressure of the test gas in the tube in real time, the sensor assembly 8 includes a temperature sensor 81 and a pressure sensor 82 which are respectively connected to the central controller 1. By setting the temperature sensor 81 and the pressure sensor 82, the temperature value and the pressure value of the test gas are sent to the central controller 1 in real time, so as to improve the accuracy of the test and facilitate the subsequent adjustment of the temperature value and the pressure value.

[0038] In order to test the sealing performance under different temperatures and pressures, the environmental simulation component 9 includes a gas heating device 91 and a pressure regulating device 92 which are connected to each other, and the gas heating device 91 and the pressure regulating device 92 are respectively connected to the central controller 1 by signals. The temperature sensor 81 and the pressure sensor 82 transmit the current temperature value and pressure value to the central controller 1, and the central controller 1 controls the gas heating device 91 and the pressure regulating device 92 to adjust to the corresponding temperature and pressure respectively according to the temperature value and the pressure value, so as to measure the axial sealing performance, and make real-time adjustments according to the parameter changes to improve the accuracy of the test results.

[0039] In order to adjust the pressure value, the pressure regulating device 92 includes an air chamber 921, a push rod 922, and an electric cylinder 923. The push rod 922 is connected to the electric cylinder 923 and moves in the air chamber 921. The electric cylinder 923 is connected to the central controller 1 by signal. The central controller 1 receives the pressure value signal transmitted by the pressure sensor 82, and determines whether the pressure value is too large or too small. If the pressure value is too large, the push rod 922 is driven by the electric cylinder 923 to move in the direction close to the electric cylinder 923 to release the pressure. If the pressure value is too small, the push rod 922 is moved in the direction away from the electric cylinder 923 to compress, thereby adjusting the pressure value and achieving the purpose of testing the sealing performance at different pressures.

[0040] In order to control the flow of the test gas, a flow control assembly 13 is provided between the gas generating device 2 and the first pneumatic butterfly valve 6. The flow control assembly 13 includes a flow proportional valve 131 and a proportional valve controller 132 which are connected to each other. The proportional valve controller 132 is connected to the central controller 1 by signal. The central controller 1 controls the proportional valve controller 132 to adjust the opening of the flow proportional valve 131 to control the flow of the test gas when it enters.

[0041] In order to recycle the test gas, a gas cooling device 14 is provided between the second pneumatic butterfly valve 7 and the polluted gas treatment device 5, and the gas cooling device 14 is connected to the central controller 1. The test gas is cooled by the gas cooling device 14 and then heated by the gas heating device 91, so that the accuracy of temperature control can be improved, and after the test is completed, the gas cooling device 14 is used again to cool the test gas in the tube before discharging it, so as to better protect the environment.

[0042] In order to seal the first pneumatic butterfly valve 6 and the second pneumatic butterfly valve 7, the first pneumatic butterfly valve 6 and the second pneumatic butterfly valve 7 both include a valve shaft 61 and a valve body 62, and the axial sealing assembly 10 includes a spacer sleeve 101, an axial sealing sleeve 102, a pre-tightening pressure sleeve 103, and a pre-tightening gland 104 which are sequentially mounted on the valve shaft 61, and the pre-tightening gland 104 is bolted to the valve body 62. By bolting the pre-tightening gland 104 to the valve body 62, the spacer sleeve 101, the axial sealing sleeve 102, the pre-tightening pressure sleeve 103, and the pre-tightening gland 104 are in close contact to ensure sealing, and the axial sealing sleeve adopts a metal butterfly frame and is filled with flexible graphite, and its lubricity and wear resistance are improved by filling the flexible graphite.

[0043] In order to improve the sealing performance, a butterfly spring 15 is provided between the pre-tightening gland 104 and the valve body 62. Since the upper surface of the pre-tightening gland 104 is uneven during the manufacturing process, the bolt cannot completely contact the upper surface of the pre-tightening gland 104 when in contact, and there will be a gap, which reduces the sealing performance. Therefore, a butterfly spring 15 is provided between the bolt and the pre-tightening gland 104. When the bolt is tightened, the butterfly spring 15 will deform to fill the gap between the two, thereby ensuring the tightness of the connection and the axial sealing performance.

[0044] In order to detect whether the air in the pipe is completely discharged, a second smoke sensor 16 is provided near the inlet end of the polluted gas treatment device 5, and the second smoke sensor 16 is connected to the central controller 1. The second smoke sensor 16 detects the concentration of ambient particles in the pipe to determine whether the air in the pipe is completely discharged. If the concentration of ambient particles changes significantly and tends to be stable, it means that the air in the pipe has been completely discharged.

[0045] like Figure 3 and Figure 4 As shown, a test method for a butterfly valve shaft axial seal test system comprises the following steps:

[0046] Step 1: Test preparation: Open the first pneumatic three-way ball valve 3 and the second pneumatic three-way ball valve 4, and open the first pneumatic butterfly valve 6 and the second pneumatic butterfly valve 7, and disconnect the connection between the gas generating device 2 and the polluted gas treatment device 5 through the first pneumatic three-way ball valve 3 or the second pneumatic three-way ball valve 4;

[0047] Step 2: exhaust the air in the pipe: start the gas generator 2 to generate test gas, and open the polluted gas treatment device 5, exhaust all the air in the original system through the polluted gas treatment device 5, adjust the gas flow rate through the flow proportional valve 131, and judge whether the test gas fills the entire system loop through the ambient particle concentration detected by the second smoke sensor 16. If the ambient particle concentration increases and tends to be stable, that is, the test gas has filled the loop, then go to step 3; otherwise, continue to exhaust the air; then disconnect the gas generator 2 and the polluted gas treatment device 5 from the main pipeline through the first pneumatic three-way ball valve 3 and the second pneumatic three-way ball valve 4, so that the test gas circulates in the main pipeline;

[0048] Step 3: Simulate the working environment: close the first pneumatic butterfly valve 6 and the second pneumatic butterfly valve 7, as well as the gas generating device 2 and the polluted gas processing device 5, and allow the test gas to flow between the first pneumatic butterfly valve 6 and the second pneumatic butterfly valve 7, start the gas heating device 91 and the pressure regulating device 92, and adjust the test gas temperature and the pressure in the pipe to meet the working environment;

[0049] Step 4: Determine the axial sealing performance: The first smoke sensor 12 detects the change of the concentration of ambient particulate matter in the axial sealing cover 11 over time. If the concentration is less than the standard value, the sealing performance is qualified; if the concentration is greater than the standard value, the sealing performance is unqualified and the axial sealing assembly 10 needs to be replaced in time;

[0050] Step 5: Cooling and recycling: turn off the gas heating device 91 and the pressure regulating device 92, turn on the gas cooling device 14, and first open the second pneumatic butterfly valve 7 to allow the test gas to enter the gas cooling device 14 due to the pressure difference, then open the first pneumatic butterfly valve 6 to allow the test gas to circulate and cool in the tube, then return to step 3 to complete the sealing test at different temperatures and pressures, and after the test is completed, go to step 6;

[0051] Step six: Exhaust the test gas: Close the gas cooling device 14, connect the gas generating device 2 and the polluted gas treatment device 5 to the main pipeline through the first pneumatic three-way ball valve 3 and the second pneumatic three-way ball valve 4, and connect the gas generating device 2 and the polluted gas treatment device 5. At this time, the gas generating device 2 only transmits external air and does not generate test gas. Open the polluted gas treatment device 5 to exhaust the test gas.

[0052] The range of different temperature values ​​tested in this embodiment is 550-700° C., and the range of different pressure values ​​is 0.5-1 MPa.

[0053] First, exhaust the air in the pipe. After the main pipeline is filled with test gas, disconnect the gas generator 2 and the polluted gas treatment device 5 from the main pipeline to allow the test gas to circulate in the main pipeline. Then close the first pneumatic butterfly valve 6 and the second pneumatic butterfly valve 7 to adjust the temperature and pressure of the test gas therebetween. After the test is completed, open the first pneumatic butterfly valve 6 and the second pneumatic butterfly valve 7 and the gas cooling device 14 to circulate and cool the test gas in the pipe to prepare gas for the next test, improve the accuracy of temperature control, and make up for the gas loss in the test area. After the test is completed, the test gas is discharged through the gas cooling device 14 and the polluted gas treatment device 5. The entire system only needs to prepare test gas once, and can test the sealing performance under different temperatures and pressures. It is more energy-efficient and reduces costs.

[0054] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0055] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for testing a butterfly valve shaft axial seal test system, characterized in that: The system comprises a gas generating device (2), a first pneumatic three-way ball valve (3), a second pneumatic three-way ball valve (4), a polluted gas treatment device (5), a first pneumatic butterfly valve (6), a second pneumatic butterfly valve (7), a sensor assembly (8) and an environmental simulation assembly (9), which are respectively connected to the central controller (1) by signals. The first pneumatic butterfly valve (6), the environmental simulation assembly (9), the sensor assembly (8) and the second pneumatic butterfly valve (7) are arranged in sequence on the main pipe. The gas generating device (2) is connected to the main pipe via the first pneumatic three-way ball valve (3), and the polluted gas treatment device (5) is connected to the main pipe via the second pneumatic three-way ball valve (4). The first pneumatic butterfly valve (6) and the second pneumatic butterfly valve (7) are both axially provided with an axial sealing assembly (10) and an axial sealing cover (11) sleeved outside the axial sealing assembly (10). The axial sealing cover (11) is provided with a first smoke sensor (12), and the first smoke sensor (12) is signal-connected to the central controller (1). The environmental simulation component (9) comprises a gas heating device (91) and a pressure regulating device (92) which are connected to each other, and the gas heating device (91) and the pressure regulating device (92) are respectively connected to the central controller (1) by signals; A flow control component (13) is provided between the gas generating device (2) and the first pneumatic butterfly valve (6), the flow control component (13) comprising a flow proportional valve (131) and a proportional valve controller (132) connected to each other, the proportional valve controller (132) being signal-connected to the central controller (1); A gas cooling device (14) is provided between the second pneumatic butterfly valve (7) and the polluted gas treatment device (5), and the gas cooling device (14) is connected to the central controller (1); A second smoke sensor (16) is provided near the inlet end of the polluted gas treatment device (5), and the second smoke sensor (16) is connected to the central controller (1) by signal. The method comprises the following steps: Step 1: Test preparation: Open the first pneumatic three-way ball valve (3) and the second pneumatic three-way ball valve (4), and open the first pneumatic butterfly valve (6) and the second pneumatic butterfly valve (7), and disconnect the connection between the gas generating device (2) and the polluted gas treatment device (5) through the first pneumatic three-way ball valve (3) or the second pneumatic three-way ball valve (4); Step 2: exhausting the air in the pipe: start the gas generator (2) to generate test gas, and open the polluted gas treatment device (5), exhaust all the air in the original system through the polluted gas treatment device (5), adjust the gas flow rate through the flow proportional valve (131), and judge whether the test gas fills the entire system loop through the ambient particle concentration detected by the second smoke sensor (16). If the ambient particle concentration increases and tends to be stable, that is, the test gas has filled the loop, then enter step 3; otherwise, continue to exhaust the air; then disconnect the gas generator (2) and the polluted gas treatment device (5) from the main pipeline through the first pneumatic three-way ball valve (3) and the second pneumatic three-way ball valve (4), so that the test gas circulates in the main pipeline; Step 3: Simulating the working environment: closing the first pneumatic butterfly valve (6) and the second pneumatic butterfly valve (7), as well as the gas generating device (2) and the polluted gas processing device (5), allowing the test gas to flow between the first pneumatic butterfly valve (6) and the second pneumatic butterfly valve (7), starting the gas heating device (91) and the pressure regulating device (92), and adjusting the test gas temperature and the pressure in the pipe to meet the working environment; Step 4: Determine the axial sealing performance: The first smoke sensor (12) detects the change in the concentration of ambient particulate matter in the axial sealing cover (11) over time. If the concentration is less than the standard value, the sealing performance is qualified. If the concentration is greater than the standard value, the sealing performance is unqualified and the axial sealing assembly (10) needs to be replaced in time. Step 5: Cooling and recycling: turn off the gas heating device (91) and the pressure regulating device (92), turn on the gas cooling device (14), and first open the second pneumatic butterfly valve (7) to allow the test gas to enter the gas cooling device (14) due to the pressure difference, then open the first pneumatic butterfly valve (6) to allow the test gas to circulate and cool in the tube, then return to step 3 to complete the sealing test at different temperatures and pressures, and after the test is completed, proceed to step 6; Step 6: Exhaust the test gas: turn off the gas cooling device (14), connect the gas generator (2) and the polluted gas treatment device (5) to the main pipeline through the first pneumatic three-way ball valve (3) and the second pneumatic three-way ball valve (4), and connect the gas generator (2) and the polluted gas treatment device (5). At this time, the gas generator (2) only transmits external air and does not generate test gas. Open the polluted gas treatment device (5) to exhaust the test gas.

2. The testing method of the butterfly valve shaft axial sealing testing system according to claim 1 is characterized in that: The sensor assembly (8) comprises a temperature sensor (81) and a pressure sensor (82) which are respectively connected to the central controller (1) by signals.

3. The testing method of the butterfly valve shaft axial sealing testing system according to claim 1 is characterized in that: The pressure regulating device (92) comprises an air chamber (921), a push rod (922), and an electric cylinder (923); the push rod (922) is connected to the electric cylinder (923) and moves in the air chamber (921); and the electric cylinder (923) is signal-connected to a central controller (1).

4. The testing method of the butterfly valve shaft axial sealing testing system according to claim 1 is characterized in that: The first pneumatic butterfly valve (6) and the second pneumatic butterfly valve (7) both comprise a valve shaft (61) and a valve body (62); the axial sealing assembly (10) comprises a spacer sleeve (101), an axial sealing sleeve (102), a pre-tightening pressure sleeve (103), and a pre-tightening gland (104) which are sequentially mounted on the valve shaft (61); the pre-tightening gland (104) is bolted to the valve body (62).

5. The testing method of the butterfly valve shaft axial seal testing system according to claim 4 is characterized in that: A butterfly spring (15) is provided between the pre-tightening gland (104) and the valve body (62).

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