Gas detection gas circuit structure
By using a leak detection air circuit structure and a differential pressure transmitter to detect the air pressure difference of the gauge under test, the problem of low leak detection efficiency in existing technologies is solved, and efficient and accurate valve and flow meter leak detection is achieved.
Patent Information
- Application Number
- CN202423092635.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-13
- Publication Date
- 2025-12-16
- Estimated Expiration
- 2034-12-13
AI Technical Summary
Existing technologies for leak detection of valves and flow meters are inefficient, manual judgment is prone to errors, and the large range of absolute pressure transmitters results in low sensitivity, making it impossible to quickly detect small leaks.
A leak detection gas path structure is adopted, including a main pipeline, branch pipelines and a reference volume tank. The differential pressure transmitter detects the gas pressure difference between the reference volume tank and the two ends of the gauge under test. Combined with valve control, efficient leak detection is achieved. The differential pressure transmitter has a small range to improve detection accuracy.
It improves the efficiency and accuracy of leak detection, enabling quick and accurate determination of whether the tested instrument is leaking, reducing errors and increasing detection efficiency.
Smart Images
Figure CN223678743U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to pressure detection technical field, especially relate to a leak detection air path structure. BACKGROUND
[0002] The valve and flowmeter need to test its leakage when leaving factory, the leak detection method of the existing technology to the detected table usually includes the following two.
[0003] The first leak detection method is: after the blind plate of the valve or flowmeter is blind, the whole is placed in water, and pressure gas is injected in the cavity, after reaching the test pressure, whether there is bubble to come out is observed by artificial observation, so as to judge whether there is leakage, but artificial judgment is easy to appear error. Another leak detection method is: after the blind plate of the valve or flowmeter is blind, the pressure pipe is led out from one end of the blind plate, a absolute pressure transmitter is installed on the pressure pipe, after pressure gas is injected in the cavity, the valve is closed after reaching the test pressure, whether the pressure value of the absolute pressure transmitter drops is observed, so as to judge whether there is leakage, but since the test pressure range of the detected table is wide, the range of the absolute pressure transmitter needs to be large, which leads to low sensitivity, in the case that the volume of the detected valve or flowmeter is large and the leakage point is small, a long time is needed for the absolute pressure transmitter to jump, and the efficiency is low.
[0004] Therefore, how to improve the leak detection efficiency of the detected table has become a technical problem to be solved in the field. UTILITY MODEL CONTENTS
[0005] The utility model aims at least to solve the technical problem of how to improve the leak detection efficiency of the detected table. The purpose is realized by the following technical scheme:
[0006] Firstly, the utility model provides a leak detection air path structure for detecting whether the detected table leaks, which comprises: a main pipeline, a first end of the main pipeline being an air inlet end; a first branch pipeline, in communication with the main pipeline through a second connection, one end of the first branch pipeline away from the second connection being connected with a gas pressure detection device, the gas pressure detection device being used for detecting the gas pressure in the main pipeline; a third valve, arranged in the main pipeline and located between the air inlet end and the second connection; a second branch pipeline, in communication with the main pipeline through a third connection, the second connection being located between the third valve and the third connection, one end of the second branch pipeline away from the third connection being used for connecting the detected table, and the second branch pipeline being provided with a fourth valve used for controlling the on-off of the second branch pipeline; and a third branch pipeline, in communication with a second end of the main pipeline, one end of the third branch pipeline away from the main pipeline being connected with a reference volume tank, the reference volume tank being a closed container with constant internal pressure, the third branch pipeline being provided with a sixth valve and a differential pressure transmitter, the sixth valve being used for controlling the on-off of the third branch pipeline, and the differential pressure transmitter being located between the reference volume tank and the sixth valve.
[0007] The leak detection gas path structure, before work, first make the second branch away from the one end of the third connection with the detected table communication, and make all the valves in the closed state;Detection, first through the gas inlet end of the main pipeline input high pressure gas, and open the third valve, the fourth valve and the sixth valve, the high pressure gas from the gas inlet end of the main pipeline into the main pipeline, observe the value of the gas pressure detection device;When the gas pressure in the main pipeline reaches the test pressure, block the gas inlet end, and close the third valve, at this time only the fourth valve and the sixth valve are opened, then observe the value of the differential pressure transmitter after stabilization;If the value of the differential pressure transmitter is greater than zero, it indicates that the pressure at one end of the reference volume tank is greater than the pressure at one end of the detected table, that is, the detected table leaks;If the value of the differential pressure transmitter is equal to zero, it indicates that the pressure at one end of the reference volume tank is equal to the pressure at one end of the detected table, that is, the detected table does not leak. It is easy to understand that since the reference volume tank is a closed container with constant internal pressure, the leakage of the reference volume tank does not need to be considered. The leak detection gas path structure determines whether the detected table leaks by detecting whether the pressure difference between the two ends of the detected table changes, and the range of the differential pressure transmitter can be set smaller, which ensures the accuracy of the detection, and therefore improves the leak detection efficiency of the detected table.
[0008] In some embodiments of the present application, the leak detection gas path structure further comprises: an exhaust pipeline, which is communicated with the main pipeline through the first connection, one end of the exhaust pipeline away from the first connection is communicated with the atmosphere, and the exhaust pipeline is provided with a second valve for controlling the opening and closing of the exhaust pipeline;And a fourth branch, the fourth branch is communicated with the main pipeline through the fourth connection, the fourth connection is located between the third connection and the second end of the main pipeline, one end of the fourth branch away from the fourth connection is communicated with the reference volume tank, and the fourth branch is provided with a fifth valve for controlling the opening and closing of the fourth branch.
[0009] In some embodiments of the present application, the gas pressure detection device is an absolute pressure transmitter.
[0010] In some embodiments of the present application, a pressure reducing valve is further arranged on the main pipeline, the pressure reducing valve is located between the gas inlet end and the third valve, and the pressure reducing valve is used for adjusting the pressure of the gas entering the main pipeline from the gas inlet end.
[0011] In some embodiments of the present application, a first valve is further arranged on the main pipeline, the first valve is located between the gas inlet end and the third valve, and the first valve is used for controlling the opening and closing of the main pipeline between the gas inlet end and the third valve.
[0012] In some embodiments of the present application, a manual valve is further arranged on the main pipeline, the manual valve is located between the gas inlet end and the third valve, and the manual valve is used for controlling the opening and closing of the path of the main pipeline between the gas inlet end and the first valve.
[0013] In some embodiments of the utility model, the manual valve is a needle valve.
[0014] In some embodiments of the utility model, the differential pressure transmitter is an intelligent differential pressure transmitter.
[0015] In some embodiments of the utility model, the range of the air pressure detection device is 0kPa-1600kPa, and the range of the differential pressure transmitter is-50kPa-50kPa.
[0016] In some embodiments of the utility model, the third valve, the fourth valve and the sixth valve are all electromagnetic valves.
[0017] The above description is only a summary of the technical scheme of the application, in order to more clearly understand the technical means of the application, which can be implemented according to the content of the specification, and in order to make the above and other purposes, characteristics and advantages of the application more obvious and easy to understand, the following specific embodiments of the application are described. BRIEF DESCRIPTION OF DRAWINGS
[0018] Various other advantages and benefits will become apparent to those of ordinary skill in the art, upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of preferred embodiments, and are not meant to limit the present application. Furthermore, like reference numerals are intended to represent the same components throughout the drawings. In the drawings:
[0019] Figure 1 A structure schematic view when the leak detection gas path structure provided by the embodiments of the utility model is connected with the detected table;
[0020] Figure 2 Another structure schematic view when the leak detection gas path structure provided by the embodiments of the utility model is connected with the detected table.
[0021] The reference signs are as follows:
[0022] 1000, leak detection gas path structure;
[0023] 100, main pipeline; 101, first connection; 102, second connection; 103, third connection; 104, fourth connection; 105, air inlet end; 106, second end;
[0024] 200, exhaust pipeline;
[0025] 301, first branch; 302, second branch; 303, third branch; 304, fourth branch;
[0026] 401, first valve; 402, second valve; 403, third valve; 404, fourth valve; 405, fifth valve; 406, sixth valve; 407, pressure reducing valve; 408, manual valve;
[0027] 500, air pressure detecting device;
[0028] 600, reference volume tank;
[0029] 700, differential pressure transmitter;
[0030] 2000, object to be inspected. DETAILED DESCRIPTION
[0031] Example embodiments of the present disclosure will be described more fully hereinafter with reference to the accompanying drawings. While example embodiments of the present disclosure are shown in the drawings, it is understood that the present disclosure can be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art.
[0032] It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises", "comprising", "includes", "including" and "has" are inclusive and therefore specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order in which they are described, unless specifically identified as an order dependent step. It is also to be understood that additional or alternative steps can be employed.
[0033] Although the terms first, second, third, and the like can be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first", "second", and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.
[0034] For the sake of description, spatial relative terms can be used herein for describing a relationship of one element or feature to another element or feature as illustrated in the figures, such as "inner", "outer", "inner side", "outer side", "under", "below", "above", "on", and the like. Such spatial relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "under" other elements or features would then be oriented "above" or "above" the other elements or features. Thus, the example term "below" can encompass both an orientation of above and below. The device can be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
[0035] Figure 1 A structure schematic view when a leak detection gas path structure provided by the embodiment of the present application is connected with a detected table is shown in Figure 1 The embodiment of the present application provides a leak detection gas path structure 1000 for detecting whether a detected table 2000 leaks, and the leak detection gas path structure 1000 comprises: a main pipeline 100, a first end of the main pipeline 100 is an air inlet end 105, and the main pipeline 100 is provided with a first valve 401; a first branch pipeline 301, in communication with the main pipeline 100 through a second connection 102, one end of the first branch pipeline 301 away from the second connection 102 is connected with a gas pressure detection device 500, and the gas pressure detection device 500 is used for detecting the gas pressure in the main pipeline 100; a third valve 403, arranged in the main pipeline 100, and the third valve 403 is located between the air inlet end 105 and the second connection 102; a second branch pipeline 302, in communication with the main pipeline 100 through a third connection 103, the second connection 102 is located between the third valve 403 and the third connection 103, one end of the second branch pipeline 302 away from the third connection 103 is used for connecting the detected table 2000, and the second branch pipeline 302 is provided with a fourth valve 404 used for controlling the on-off of the second branch pipeline 302; and a third branch pipeline 303, in communication with a second end 106 of the main pipeline 100, one end of the third branch pipeline 303 away from the main pipeline 100 is connected with a reference volume tank 600, the reference volume tank 600 is a closed container with constant internal pressure, the third branch pipeline 303 is provided with a sixth valve 406 and a differential pressure transmitter 700, the sixth valve 406 is used for controlling the on-off of the third branch pipeline 303, and the differential pressure transmitter 700 is located between the reference volume tank 600 and the sixth valve 406.
[0036] Wherein, it is easy to understand that the first valve 401 can be arranged on the main pipeline 100, the first valve 401 is arranged between the air inlet end 105 and the third valve 403, the first valve 401 is used to control the opening and closing of the main pipeline 100 between the air inlet end 105 and the third valve 403, opening the first valve 401 can realize the gas supply of the main pipeline 100, closing the first valve 401 can realize the plugging of the air inlet end 105, and the operation is more simple and convenient.
[0037] Specifically, in this embodiment, before the work of the leak detection gas path structure 1000, the end of the second branch 302 away from the third connection 103 is communicated with the detected table 2000, and all the valves are in the closed state; during detection, the first valve 401, the third valve 403, the fourth valve 404 and the sixth valve 406 are opened, the high-pressure gas is input into the main pipeline 100 from the air inlet end 105 of the main pipeline 100, and the indication value of the gas pressure detection device 500 is observed; when the gas pressure in the main pipeline 100 reaches the test pressure, the first valve 401 and the third valve 403 are closed, that is, only the fourth valve 404 and the sixth valve 406 are opened at this time, and then the indication value of the differential pressure transmitter 700 after stabilization is observed; if the indication value of the differential pressure transmitter 700 is greater than zero, it means that the pressure at one end of the reference volume tank 600 is greater than the pressure at one end of the detected table 2000, that is, the detected table 2000 leaks; if the indication value of the differential pressure transmitter 700 is equal to zero, it means that the pressure at one end of the reference volume tank 600 is equal to the pressure at one end of the detected table 2000, that is, the detected table 2000 does not leak. It is easy to understand that since the reference volume tank 600 is a closed container with constant internal pressure, the leakage of the reference volume tank 600 does not need to be considered.
[0038] Wherein, it is easy to understand that the size of the test pressure is related to the specification of the detected table 2000, and the appropriate test pressure should be determined according to the actual working condition requirements; and the type of the detected table 2000 can also be selected according to the actual working condition requirements, such as valves, flow meters, etc., without specific limitation.
[0039] Therefore, the leak detection gas path structure 1000 determines whether the detected table 2000 leaks by detecting whether the pressure difference between the two ends of the reference volume tank 600 and the detected table 2000 changes, and the range of the differential pressure transmitter 700 can be set smaller, which guarantees the accuracy of detection, and therefore improves the efficiency of leak detection of the detected table 2000.
[0040] With the increase of the number of uses, the service life of the leak detection air path structure 1000 will gradually decrease, in order to further guarantee the detection accuracy of the detected table 2000, before the detected table 2000 is leak detected, the reliability of the leak detection air path structure 1000 also needs to be guaranteed. It is easy to understand that according to the arrangement of the leak detection air path structure 1000 of the embodiment, the leakage of the first valve 401 and the second valve 402 can be judged alone, and it is good to judge; and the valves which have complex influence on the leak detection result include the third valve 403, the fourth valve 404 and the sixth valve 406. Therefore, whether the leak detection air path structure 1000 has a gas leakage condition can be detected before the detected table 2000 is leak detected, that is, the leak detection air path structure 1000 is configured to have a self-leak detection function.
[0041] Figure 2 Another leak detection air path structure provided by the embodiment of the utility model and the structure schematic diagram when connecting with the detected table are shown as Figure 2 Specifically, according to an optional embodiment of the utility model, the leak detection air path structure 1000 further comprises: an exhaust pipeline 200, which is communicated with the main pipeline 100 through a first connection 101, the first valve 401 is located between the air inlet end 105 and the first connection 101, one end of the exhaust pipeline 200 away from the first connection 101 is communicated with the atmosphere, and the exhaust pipeline 200 is provided with a second valve 402 for controlling the on-off of the exhaust pipeline 200; and a fourth branch 304, which is communicated with the main pipeline 100 through a fourth connection 104, the fourth connection 104 is located between the third connection 103 and the second end 106 of the main pipeline 100, one end of the fourth branch 304 away from the fourth connection 104 is communicated with the reference volume tank 600, and the fourth branch 304 is provided with a fifth valve 405 for controlling the on-off of the fourth branch 304.
[0042] In the embodiment, the self-leak detection process of the leak detection air path structure 1000 will be described in detail as follows: Figure 2
[0043] Firstly, the first valve 401, the third valve 403, the fifth valve 405 and the sixth valve 406 are opened, the high-pressure gas is injected from the air inlet end 105 of the main pipeline 100, and the indication value of the gas pressure detection device 500 is observed; when the gas pressure in the main pipeline 100 reaches the test pressure, the first valve 401 and the third valve 403 are closed, the second valve 402 is opened for pressure relief, and then the indication value of the gas pressure detection device 500 is observed whether it decreases, if the gas pressure in the main pipeline 100 decreases, it may be that the third valve 403 and the fourth valve 404 are internally leaked, or part of the pipeline or valve in the leak detection air path structure 1000 is externally leaked;
[0044] Then, the specific reason of the pressure drop in the main pipeline 100 is determined. First, the part of the pipeline or the valve surface in the leak detection pipeline structure 1000 is detected by the foam water. If there is no leak point, it means that there is no external leakage. Then, the pressure of the high-pressure gas entering the main pipeline 100 is increased to be greater than the test pressure, the first valve 401 is opened, and the value of the pressure detection device 500 is observed. If the value of the pressure detection device 500 does not change, it means that the third valve 403 does not leak, and the fourth valve 404 leaks. If the value of the pressure detection device decreases slowly, it means that the third valve 403 and the fourth valve 404 both leak. If the value of the pressure detection device increases, it means that the third valve 403 leaks, and the fourth valve 404 may leak. After replacing a perfect third valve 403, the above test is repeated to determine whether the fourth valve 404 leaks.
[0045] The above two end sections determine the external leakage and the internal leakage of the third valve 403 and the fourth valve 404. The following describes the judgment method of the internal leakage of the fifth valve 405 and the sixth valve 406.
[0046] Continuing to refer to Figure 2 On the basis that the pipeline, the third valve 403, and the fourth valve 404 are ensured not to leak, the second valve 402, the fourth valve 404, the fifth valve 405, and the sixth valve 406 are kept closed, the first valve 401 and the third valve 403 are opened, the high-pressure gas is input into the main pipeline 100 from the gas inlet end 105, and the value of the differential pressure transmitter 700 is observed to determine the pressure difference between the reference volume tank 600 and the sixth valve 406. The results are divided into the following three cases:
[0047] The first case is that the value of the differential pressure transmitter 700 does not change, which means that the fifth valve 405 and the sixth valve 406 do not leak, or both of them leak but cause the same speed of pressure change at both ends. Then, the first valve 401 is closed and the second valve 402 is opened for pressure relief. After the pressure relief is completed, the sixth valve 406 is opened. If the value of the differential pressure transmitter 700 still does not change, it means that the fifth valve 405 and the sixth valve 406 do not leak and cause the same speed of pressure change at both ends. If the differential pressure transmitter 700 shows that the pressure of the reference volume tank 600 is high, it means that the fifth valve 405 and the sixth valve 406 both leak. As described above, since the reference volume tank 600 is a closed container with constant internal pressure, the leakage of the reference volume tank 600 does not need to be considered.
[0048] In the second case, the differential pressure transmitter 700 shows that the air pressure at the end of the reference volume tank 600 is higher than the air pressure at the end of the sixth valve 406, which indicates that the fifth valve 405 leaks, the sixth valve 406 does not leak, or both the fifth valve 405 and the sixth valve 406 leak and the leakage at the end of the fifth valve 405 is greater than the leakage at the end of the sixth valve 406.
[0049] In the third case, the differential pressure transmitter 700 shows that the air pressure at the end of the sixth valve 406 is higher than the air pressure at the end of the reference volume tank 600, which indicates that the sixth valve 406 leaks, the fifth valve 405 does not leak, or both the fifth valve 405 and the sixth valve 406 leak and the leakage at the end of the sixth valve 406 is greater than the leakage at the end of the fifth valve 405, and then the first valve 401 is closed and the second valve 402 is opened for pressure relief, and after the pressure relief is completed, the sixth valve 406 is opened, and if the differential pressure transmitter 700 shows that the air pressures at both ends are the same, it indicates that the fifth valve 405 does not leak, and if the differential pressure transmitter shows that the air pressure at the end of the fifth valve 405 is higher, it indicates that the fifth valve 405 also leaks.
[0050] Therefore, the leak detection air path structure 1000 provided by the embodiment can efficiently and accurately perform self-leak detection, thereby ensuring the accuracy of subsequent leak detection of the detected table 2000, and further improving the efficiency of leak detection of the detected table 2000.
[0051] According to an optional embodiment of the utility model, the range of the differential pressure transmitter 700 is -50kPa~50kPa.
[0052] In the embodiment, in order to ensure the accuracy of detection, the range of the differential pressure transmitter 700 can be set smaller to improve the sensitivity of detection.
[0053] It is easy to understand that the type and range of the differential pressure transmitter 700 in the embodiment are only for distance description, and in actual working conditions, it can be determined according to specific working condition requirements without limitation.
[0054] According to an optional embodiment of the utility model, the air pressure detection device 500 is an absolute pressure transmitter.
[0055] In the embodiment, the absolute pressure transmitter has high precision and good stability, and can accurately measure the air pressure value in the main pipeline 100.
[0056] According to an optional embodiment of the utility model, the range of the absolute pressure transmitter is 0kPa-1600kPa.
[0057] In the embodiment, it is easy to understand that, since the test pressure range of the tested meter 2000 is wide, the absolute pressure transmitter with a large range is needed to adapt to different specifications of the tested meter 2000; therefore, the range of the absolute pressure transmitter in the embodiment is also set to be large, which is 0kPa-1600kPa (this range is only for illustration, and the specific range can be determined according to the working condition of the test piece) ; in addition, since the differential pressure transmitter 700 exists, the final judgment of whether the tested meter 2000 leaks is relied on the differential pressure transmitter 700 with a small range, and the absolute pressure transmitter with a large range will not affect the final leak detection result of the tested meter 2000.
[0058] Reference is made to Figure 1 and Figure 2 According to an optional embodiment of the utility model, the main pipeline 100 is further provided with a pressure reducing valve 407, the pressure reducing valve 407 is arranged between the gas inlet end 105 and the third valve 403, and the pressure reducing valve 407 is used for adjusting the pressure of the gas entering the main pipeline 100 from the gas inlet end 105.
[0059] In the embodiment, specifically, the pressure reducing valve 407 can be arranged between the gas inlet end 105 and the first valve 401, since the test pressures adapted by different tested meters 2000 are different, the pressure reducing valve 407 is arranged between the gas inlet end 105 and the first valve 401, so as to adjust the air pressure of the gas entering the main pipeline 100, thereby adapting to various specifications of the tested meter 2000.
[0060] Reference is made to Figure 1 and Figure 2 According to an optional embodiment of the utility model, the main pipeline 100 is further provided with a manual valve 408, the manual valve 408 is located between the gas inlet end 105 and the third valve 403, and the manual valve 408 is used for controlling the opening and closing of the path of the main pipeline 100 between the gas inlet end 105 and the first valve 401.
[0061] In the embodiment, it is easy to understand that, when the leak detection of the tested meter 2000 is finished, the operator can close the manual valve 408 to disconnect the path between the gas inlet end 105 and the first valve 401, thereby ensuring the safety of the whole leak detection gas path structure 1000.
[0062] Specifically, according to an optional embodiment of the utility model, the manual valve 408 is a needle valve.
[0063] In the embodiment, the needle valve has the advantages of high reliability, simple structure and convenient assembly.
[0064] It is easily understood that the manual valve 408 can be selected as the needle valve in the embodiment by way of example; in actual working conditions, a suitable type of manual valve 408 can be selected according to the working condition requirements, such as a ball valve, a gate valve and the like, without specific limitation.
[0065] According to an optional embodiment of the utility model, the third valve 403, the fourth valve 404 and the sixth valve 406 are all solenoid valves.
[0066] In the embodiment, since the solenoid valve can realize remote operation through an electric signal to control the on-off of the valve, the process operation of the leak detection test table 2000 described above can be made more convenient.
[0067] It is easily understood that when the first valve 401 is arranged on the main pipeline 100, the first valve 401 can also be arranged as a solenoid valve.
[0068] In addition, when the leak detection gas path structure 1000 further comprises a fourth branch 304 and an exhaust pipeline 200, and the fifth valve 405 is arranged on the fourth branch 304 and the second valve 402 is arranged on the exhaust pipeline 200, the second valve 402 and the fifth valve 405 can also be selected as solenoid valves, so that the self-leak detection process of the leak detection gas path structure 1000 described above can also be controlled by an electric signal to control the on-off of the valve throughout the process, thereby improving the efficiency of the self-leak detection of the leak detection gas path structure 1000.
[0069] The above is only a preferred specific embodiment of the utility model, but the protection scope of the utility model is not limited to this, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the utility model, which should be covered in the protection scope of the utility model. Therefore, the protection scope of the utility model should be subject to the protection scope of the claims.
Claims
1. A leak detection air circuit structure for detecting whether a meter under test is leaking, characterized in that, The air leakage testing circuit structure comprises: a main pipeline, a first end of the main pipeline being an air inlet end; a first branch pipeline, the first branch pipeline being communicated with the main pipeline through a second connection, one end of the first branch pipeline away from the second connection being connected with an air pressure detection device, the air pressure detection device being used for detecting air pressure in the main pipeline; a third valve, the third valve being arranged in the main pipeline and located between the air inlet end and the second connection; a second branch pipeline, the second branch pipeline being communicated with the main pipeline through a third connection, the second connection being located between the third valve and the third connection, one end of the second branch pipeline away from the third connection being used for connecting the tested meter, and the second branch pipeline being provided with a fourth valve used for controlling opening and closing of the second branch pipeline; and a third branch pipeline, the third branch pipeline being communicated with a second end of the main pipeline, one end of the third branch pipeline away from the main pipeline being connected with a reference volume tank, the reference volume tank being a closed container with constant internal pressure, the third branch pipeline being provided with a sixth valve and a differential pressure transmitter, the sixth valve being used for controlling opening and closing of the third branch pipeline, and the differential pressure transmitter being located between the reference volume tank and the sixth valve.
2. The leak testing air passage structure according to claim 1, characterized by The air leakage testing circuit structure further comprises: an exhaust pipeline, the exhaust pipeline being communicated with the main pipeline through a first connection, one end of the exhaust pipeline away from the first connection being communicated with the atmosphere, the exhaust pipeline being provided with a second valve used for controlling opening and closing of the exhaust pipeline; and a fourth branch pipeline, the fourth branch pipeline being communicated with the main pipeline through a fourth connection, the fourth connection being located between the third connection and the second end of the main pipeline, one end of the fourth branch pipeline away from the fourth connection being communicated with the reference volume tank, and the fourth branch pipeline being provided with a fifth valve used for controlling opening and closing of the fourth branch pipeline.
3. The leak testing air passage structure according to claim 1, characterized by The air pressure detection device is an absolute pressure transmitter.
4. The leak testing air passage structure according to claim 1, characterized by The main pipeline is further provided with a pressure reducing valve, the pressure reducing valve being located between the air inlet end and the third valve, the pressure reducing valve being used for adjusting pressure of gas entering the main pipeline from the air inlet end.
5. The leak testing gas passage structure according to claim 1, wherein The main pipeline is further provided with a first valve, the first valve being located between the air inlet end and the third valve, the first valve being used for controlling opening and closing of the main pipeline between the air inlet end and the third valve.
6. The leak testing air passage structure according to claim 5, wherein The main pipeline is further provided with a hand valve, the hand valve being located between the air inlet end and the third valve, the hand valve being used for controlling opening and closing of a path of the main pipeline between the air inlet end and the first valve.
7. The leak testing gas passage structure according to claim 6, wherein The hand valve is a needle valve.
8. The leak testing air path structure according to claim 1, characterized by, The differential pressure transmitter is an intelligent differential pressure transmitter.
9. The leak testing gas passage structure according to claim 1, wherein A range of the air pressure detection device is 0 kPa-1600 kPa, and a range of the differential pressure transmitter is -50 kPa-50 kPa.
10. The leak testing gas path structure according to any one of claims 1 to 9, characterized by, The third valve, the fourth valve and the sixth valve are all electromagnetic valves.