Leakage rate calibration device for differential pressure type airtight leak detector

Abstract

The utility model discloses a leak rate calibration device for a differential pressure type airtight leak detector. The leak rate calibration device comprises an air supply assembly; the air supply assembly can inflate the differential pressure type airtight leak detector, the second port is connected with a first valve body, the first valve body is in a closed state, and the third port is connected with a second valve body; the adjustable positive pressure standard leak hole is connected with a third port of the differential pressure type airtight leak detector through a first pipeline, and the second valve body is arranged on the first pipeline; the volume tank is communicated with the first pipeline through a second pipeline, and the third valve body is arranged on the second pipeline; and the vacuum pump is connected with the volume tank and used for vacuumizing the volume tank, and a fourth valve body is further arranged between the vacuum pump and the volume tank. By calculating the error of the leakage rate of the differential pressure type airtight leak detector caused by the first pipeline and the second pipeline, the calibration efficiency is high, the first pipeline and the second pipeline cannot be damaged, and the problem that calibration cannot be carried out or the calibration period is long in the past is effectively solved.

Description

Technical Field

[0001] The utility model relates to the field of pressure vacuum calibration, in particular to a leakage rate calibration device of a differential pressure airtight leak detector. Background Art

[0002] As a device for measuring sealing and leak rate of leak holes, differential pressure leak detectors are widely used in deep space and deep sea, sealing systems of high-end manufacturing, biomedical safety and other fields. The main calibration parameters of existing differential pressure leak detectors are: pressure, differential pressure, and leak rate. At present, the calibration methods of pressure and differential pressure are relatively mature, but there is no systematic calibration method for leak rate calibration. However, as an important parameter in differential pressure leak detectors, the leak rate affects people's life and production safety. Inaccurate or uncalibrated calibration of the leak rate will affect the development of high-end manufacturing, energy vehicles, and gas appliances, and may greatly cause accidents such as fires; at the same time, the instability or inaccuracy of the leak rate in the sealing system will lead to different amounts of gas pushed out by the thrusters in deep space and deep sea, resulting in large deviations in the forward direction. At present, for the calibration of the leak rate, no specific values ​​are given for the internal volume of different types of equipment, and the volume of the pipeline is not taken into account, so the calibration of the leak rate cannot be carried out. Utility Model Content

[0003] In view of this, the embodiment of the present application is to solve at least one problem existing in the background technology and the purpose of the present application is achieved through the following technical solution: a leakage rate calibration device of a differential pressure airtight leak detector, comprising:

[0004] Air supply components;

[0005] A differential pressure airtight leak detector, comprising a first port, a second port and a third port, wherein the first port is connected to the air supply component, the air supply component can inflate the differential pressure airtight leak detector, the second port is connected to a first valve body, the first valve body is in a closed state, and the third port is connected to a second valve body;

[0006] An adjustable positive pressure standard leak hole is connected to the third port of the differential pressure airtight leak detector through a first pipeline, and the second valve body is arranged on the first pipeline;

[0007] A volume tank is connected to the first pipeline through a second pipeline, and the third valve body is arranged on the second pipeline;

[0008] A vacuum pump is connected to the volume tank and is used to evacuate the volume tank. A fourth valve body is also provided between the vacuum pump and the volume tank.

[0009] Optionally, the above-mentioned differential pressure airtight leak detector leakage rate calibration device further includes a first pressure gauge, the first pressure gauge is arranged between the second valve body and the adjustable positive pressure standard leak hole, and the third valve body is located between the second valve body and the first pressure gauge.

[0010] Optionally, the leakage rate calibration device of the differential pressure airtight leak detector mentioned above further comprises a second pressure gauge, and the second pressure gauge is arranged between the vacuum pump and the volume tank.

[0011] Optionally, in the above-mentioned differential pressure airtight leak detector leakage rate calibration device, the air supply assembly includes a dry air tank, a pressure-stabilizing tank connected to the dry air tank, and a pressure reducing valve, and the pressure reducing valve connects the pressure-stabilizing tank and the first port of the differential pressure airtight leak detector.

[0012] Optionally, in the above-mentioned differential pressure airtight leak detector leakage rate calibration device, a filter is further provided between the pressure stabilizing tank and the pressure reducing valve.

[0013] Optionally, in the above-mentioned differential pressure airtight leak detector leakage rate calibration device, the gas supply assembly also includes a third pressure gauge arranged between the pressure reducing valve and the differential pressure airtight leak detector.

[0014] Optionally, in the above-mentioned differential pressure airtight leak detector leakage rate calibration device, the first pipeline and the second pipeline are both pressure-resistant pipes.

[0015] The utility model adopts the above-mentioned structure to achieve the following beneficial effects: by setting an adjustable positive pressure standard leak hole connected to the differential pressure airtight leak detector, a volume tank with a known volume, and a vacuum pump connected to the volume tank, the vacuum pump can be used to evacuate the volume tank and obtain the volumes of the first pipeline and the second pipeline through a static expansion method, thereby calculating the error caused by the first pipeline and the second pipeline to the leakage rate of the differential pressure airtight leak detector, with high calibration efficiency and no damage to the first pipeline and the second pipeline, effectively solving the problem of being unable to calibrate or having a long calibration cycle in the past. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The utility model discloses a leakage rate calibration device for a differential pressure airtight leak detector.

[0017] Among them, 1-dry air tank, 2-pressure stabilizing tank, 3-filter, 4-pressure reducing valve, 5-third pressure gauge, 6-differential pressure airtight leak detector, 7-solenoid valve, 8-differential pressure sensor, 9-first valve body, 10-second valve body, 11-first pressure gauge, 12-adjustable positive pressure standard leak, 13-third valve body, 14-fourth valve body, 15-volume tank, 16-second pressure gauge, 17-vacuum pump, 18-first pipeline, 19-second pipeline. DETAILED DESCRIPTION

[0018] The technical solution of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] In the description of the present utility model, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance. The present utility model is further described in detail below in conjunction with the accompanying drawings.

[0020] Please refer to Figure 1 As shown, a differential pressure airtight leak detector leakage rate calibration device (hereinafter referred to as calibration device) shown in a preferred embodiment of the utility model comprises an air supply component, a differential pressure airtight leak detector 6, an adjustable positive pressure standard leak hole 12, a volume tank 15, and a vacuum pump 17. Among them, the differential pressure airtight leak detector 6 comprises a first port, a second port and a third port, the first port is connected to the above-mentioned air supply component, so that the air supply component can inflate the differential pressure airtight leak detector, the second port is connected to a first valve body 9, and the first valve body 9 is always in a closed state, and the third port is connected to a second valve body 10; the adjustable positive pressure standard leak hole 12 is connected to the third port through a first pipeline 18, and the second valve body 10 is arranged on the first pipeline 18; the volume tank 15 is connected to the first pipeline 18 through a second pipeline 19, and the third valve body 13 is arranged on the second pipeline 19; the vacuum pump 17 is connected to the volume tank 15, used to evacuate the volume tank 15, and a fourth valve body 14 is also arranged between the vacuum pump 17 and the volume tank 15. It should be noted that, in this embodiment, the adjustable positive pressure standard leak hole 12 is used as a measurement standard; the first pipe 18 and the second pipe 19 are both pressure-resistant pipes. The differential pressure airtight leak detector 6 also includes a solenoid valve 7 and a differential pressure sensor 8, and its specific working principle and structure are mature technologies in this field and are not described in detail here.

[0021] The calibration device further includes a first pressure gauge 11, which is disposed between the second valve body 10 and the adjustable positive pressure standard leak hole 12, and the third valve body 13 is located between the second valve body 10 and the first pressure gauge 11. The calibration device further includes a second pressure gauge 14, which is disposed between the vacuum pump 17 and the volume tank 15.

[0022] The gas supply assembly includes a dry air tank 1, a pressure-stabilizing tank 2 connected to the dry air tank 1, and a pressure reducing valve 4, wherein the pressure reducing valve 4 connects the pressure-stabilizing tank 2 and the first port of the differential pressure airtight leak detector. The dry air tank 1 is used to provide gas, and the pressure-stabilizing tank 2 can stabilize the airflow from the dry air bottle 1 to prevent excessive airflow from damaging the differential pressure airtight leak detector 6, and can further stabilize the temperature of the gas to prevent the temperature from affecting the measurement results. The pressure reducing valve 4 can be provided to realize manual control and adjustment of the intake pressure.

[0023] A filter 3 is also provided between the pressure stabilizing tank 2 and the pressure reducing valve 4. The filter 3 is provided for filtering impurities in the gas to prevent the impurities in the gas from clogging the first port of the differential pressure airtight leak detector.

[0024] The gas supply assembly further includes a third pressure gauge 5 disposed between the pressure reducing valve 4 and the differential pressure airtight leak detector 6. The third pressure gauge 5 is the same as the first pressure gauge 11 and the second pressure gauge 14, and is used to detect pressure at different locations.

[0025] In summary, the calibration process of the differential pressure airtight leak detector leakage rate calibration device shown in the utility model is as follows: the intake air is supplied through the dry air bottle 1, and after passing through the pressure regulating tank 2 and the filter 3, the gas enters the differential pressure airtight leak detector 6 through the first port. At this time, the second valve body 10, the third valve body 13 and the fourth valve body 14 are all in the open state. After the inflation time and the balance time set on the differential pressure airtight leak detector 6 have passed in turn, the leak detector starts the detection time. At this time, the outlet of the adjustable positive pressure standard leak hole is closed, and the third valve is closed. The vacuum pump 17 is started to evacuate the volume tank 15 to a preset value, and the pressure of the volume tank 15 is recorded by the second pressure gauge 14, which is recorded as P1. It should be noted that the volume tank 15 in this embodiment is a volume tank 15 with a known volume, which is recorded as V1. The volume tank 15 can be 100mL, 200mL, 300mL, 400mL, etc. Its specific value is not limited here and can be determined according to actual conditions. Then, after the air pressure in the volume tank 15 is stabilized, the fourth valve is closed first, and then the third valve is opened. At this time, the gas in the volume tank 15 will expand into the first pipe 18 and the second pipe 19, and the value on the first pressure gauge 11 is read as P2, and the internal volume (the sum of the volumes of the first pipe 18, the second pipe 19 and the volume tank 15) is recorded as V2. The static expansion method can be used to list the formula P1V1=P2V2, thereby obtaining V2=P1V1 / P2. Since the volume tank 15 has a known volume V1, the sum of the first pipe 18 and the second pipe 19 V0=V2-V1. It should be noted that, due to the vacuum, the effect of gas expansion on temperature is small, and the effect of temperature on the result is ignored.

[0026] Next, the obtained internal volume V2 is input into the interface of the differential pressure airtight leak detector 6, and the adjustable positive pressure standard leak hole is opened. After waiting for a period of time, the display screen of the differential pressure airtight leak detector 6 will calculate and display the leakage rate. At this time, the obtained leakage rate is compared with the known positive pressure standard leak rate, so as to achieve the purpose of calibration. In simple terms, it can be understood that the leakage rate of the differential pressure airtight leak detector 6 measured in the prior art includes the error caused by the first pipe 18 and the second pipe 19 to the leakage rate, and the present application calculates the volume of the first pipe 18 and the second pipe 19, and takes into account the error caused by the volume of the first pipe 18 and the second pipe 19 to the leakage rate, thereby obtaining the actual leakage rate of the differential pressure airtight leak detector 6. The calibration device has high calibration efficiency and will not cause damage to the first pipe 18 and the second pipe 19, effectively solving the problem of being unable to calibrate or having a long calibration cycle in the past.

[0027] The above description of the utility model and its implementation methods is not restrictive. The drawings show only one implementation method of the utility model, and the actual structure is not limited thereto. In short, if ordinary technicians in this field are inspired by it and design structural methods and embodiments similar to the technical solution without creativity without departing from the purpose of the invention of the utility model, they should all fall within the protection scope of the utility model.

Claims

1. A leakage rate calibration device for a differential pressure airtight leak detector, characterized in that: include: Air supply components; A differential pressure airtight leak detector, comprising a first port, a second port and a third port, wherein the first port is connected to the air supply component, the air supply component can inflate the differential pressure airtight leak detector, the second port is connected to a first valve body, the first valve body is in a closed state, and the third port is connected to a second valve body; An adjustable positive pressure standard leak hole is connected to the third port of the differential pressure airtight leak detector through a first pipeline, and the second valve body is arranged on the first pipeline; A volume tank is connected to the first pipeline through a second pipeline, and a third valve body is arranged on the second pipeline; A vacuum pump is connected to the volume tank and is used to evacuate the volume tank. A fourth valve body is also provided between the vacuum pump and the volume tank.

2. The differential pressure airtight leak detector leakage rate calibration device according to claim 1, characterized in that: The calibration device further comprises a first pressure gauge, which is arranged between the second valve body and the adjustable positive pressure standard leak hole, and the third valve body is located between the second valve body and the first pressure gauge.

3. The leakage rate calibration device of differential pressure airtight leak detector according to claim 1, characterized in that: The calibration device also includes a second pressure gauge, which is arranged between the vacuum pump and the volume tank.

4. The leakage rate calibration device of differential pressure airtight leak detector according to claim 1, characterized in that: The air supply assembly includes a dry air tank, a pressure-stabilizing tank connected to the dry air tank, and a pressure-reducing valve, wherein the pressure-reducing valve connects the pressure-stabilizing tank and a first port of the differential pressure airtight leak detector.

5. The leakage rate calibration device of differential pressure airtight leak detector according to claim 4, characterized in that: A filter is also arranged between the pressure stabilizing tank and the pressure reducing valve.

6. The leakage rate calibration device for differential pressure airtight leak detector according to claim 4, characterized in that: The gas supply assembly further includes a third pressure gauge disposed between the pressure reducing valve and the differential pressure airtight leak detector.

7. The leakage rate calibration device of differential pressure airtight leak detector according to claim 1, characterized in that: The first pipeline and the second pipeline are both pressure-resistant pipes.

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