Gas pipeline gas tightness detection device and detection method

Abstract

The invention discloses a gas pipeline airtightness detection device and detection method. The gas pipeline airtightness detection device comprises a pressurizing unit, a temperature sensing unit, a pressure sensing unit, a three-way valve, an atmospheric pressure sensing unit, a data acquisition and processing unit, a data transmission unit and a power supply module. The temperature sensing unit clings to the outer wall of the gas pipeline and is arranged in buried soil; one end of the three-way valve is communicated with the gas pipeline, and the other two ends of the three-way valve are respectively connected with the pressure sensing unit and the pressurizing unit; the temperature sensing unit, the pressure sensing unit and the atmospheric pressure sensing unit are all connected with the data acquisition and processing unit, and the data acquisition and processing unit is connected with the rear-end platform through the data transmission unit. The air tightness detection device has the advantages of simple structure, accurate air tightness detection and the like.

Description

Technical Field

[0001] The present invention mainly relates to the technical field of gas detection, and in particular to a gas pipeline air tightness detection device and a detection method. Background Art

[0002] Before the urban gas pipeline is put into operation, it is necessary to carry out air tightness testing in accordance with industry standards after the pipeline is laid. The air tightness test mainly relies on relevant personnel to record the changes in pressure parameters in the pipeline over a period of time.

[0003] Most measuring devices on the market often use the temperature test value in the device head or the temperature test value in the pressure pipeline to replace the temperature measurement value in the pipeline. Since the device head and the pressure pipeline are at a certain distance from the buried gas pipeline and are easily affected by the external environment such as sunlight, rain, ice and snow, there is a large temperature measurement error.

[0004] In terms of detection methods, traditional air tightness detection devices compare the corrected pressure drop of each collection point, the software program design is cumbersome, or the data is packaged and sent to the background for analysis, increasing labor costs. Summary of the invention

[0005] In view of the technical problems existing in the prior art, the present invention provides a gas pipeline air tightness detection device and detection method with accurate air tightness detection.

[0006] In order to solve the above technical problems, the technical solution proposed by the present invention is: A gas pipeline air tightness detection device comprises a charging unit, a temperature sensing unit, a pressure sensing unit, a three-way valve, an atmospheric pressure sensing unit, a data acquisition processing unit, a data transmission unit and a power module; the temperature sensing unit is close to the outer wall of the gas pipeline and is placed in the buried soil; one end of the three-way valve is connected to the gas pipeline, and the other two ends are respectively connected to the pressure sensing unit and the charging unit; the temperature sensing unit, the pressure sensing unit and the atmospheric pressure sensing unit are all connected to the data acquisition processing unit, and the data acquisition processing unit is connected to a back-end platform through the data transmission unit.

[0007] Preferably, the charging unit comprises a hose, a pressure gauge and an inflation valve, one end of the hose is connected to the three-way valve, and the other end is connected to the inflation valve; the pressure gauge is located on the hose.

[0008] Preferably, the atmospheric pressure sensing unit, the data acquisition and processing unit, the data transmission unit and the power supply module are all built into a meter head of the detection device.

[0009] Preferably, the temperature sensing unit is detachably connected to a meter head of the detection device via a cable.

[0010] Preferably, the pressure sensing unit is directly connected to the gauge head of the detection device via a thread or a flange.

[0011] The present invention also discloses a detection method based on the gas pipeline air tightness detection device as described above, comprising the steps of: Open the three-way valve to connect the gas pipeline to the pressure charging unit. After the pressure in the gas pipeline reaches the preset pressure value through the pressure charging unit, close the pressure charging unit. Open the three-way valve to disconnect the gas pipeline from the pressure charging unit and connect it to the pressure sensing unit; The air tightness detection device should work stably for a certain period of time, and the test data during this period will not be used; Initially, the temperature sensor unit test value is T1, the pressure sensor unit test value is H1, and the atmospheric pressure sensor unit test value is B1; set the test value H 1 is the base value; In the test range, the minimum conversion value in the test range is sought to obtain the corrected pressure drop; if the corrected pressure drop is less than the preset value, it indicates that the air tightness test is qualified.

[0012] Preferably, the conversion value is specifically:

[0013] in, H 1. H 2 is the measured value of the pressure in the pipeline at the beginning and end of the air tightness test. B 1. B 2 is the atmospheric pressure measurement value at the beginning and end of the airtightness test. T 1. T 2 is the temperature measurement value in the pipeline at the beginning and end of the air tightness test; is the converted value.

[0014] Preferably, the corrected pressure drop .

[0015] Preferably, the test interval is 24h to 30h.

[0016] Preferably, the minimum conversion value in the test interval is found by bubble sort or shell sort. , n is an integer and n>1.

[0017] Compared with the prior art, the advantages of the present invention are: The gas pipeline air tightness detection device in the present invention measures the temperature and pressure of the gas inside the gas pipeline and the external atmospheric pressure value over a period of time, and determines whether the pressure change inside the gas pipeline is within the corrected pressure drop range by converting the gas standard state equation, thereby determining whether the gas pipeline meets the air tightness requirements.

[0018] Compared with the wireless remote gas pipeline air tightness detection equipment on the market, the present invention measures the temperature of the outer wall of the pipeline while measuring the pressure in the pipeline, which can reduce the influence of external environment such as sunlight, rain, ice and snow, and reduce the temperature measurement error. In terms of detection method, the present invention uses bubble sorting or Hill sorting method to find the minimum value of each collection point in the test interval, and can simply judge whether the pipeline air tightness meets the requirements by comparing the corrected pressure drop only once. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a diagram showing an embodiment of the airtightness detection device of the present invention in a specific application.

[0020] Figure 2 It is a schematic diagram of the correction pressure drop of the present invention.

[0021] Legend: 1. Ground; 2. Soil; 3. Meter head; 3a. Temperature sensing unit; 3b. Pressure sensing unit; 4. Gas pipeline; 5. Three-way valve; 6. Hose; 7. Pressure gauge; 8. Inflating valve. DETAILED DESCRIPTION

[0022] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0023] like Figure 1 As shown, the gas pipeline air tightness detection device provided by the embodiment of the present invention includes a temperature sensing unit 3a, a pressure sensing unit 3b, a three-way valve 5, and an atmospheric pressure sensing unit built into the device header 3, a data acquisition and processing unit, a data transmission unit and a power module (not shown in the figure); the temperature sensing unit 3a is close to the outer wall of the gas pipeline 4 and is placed in the buried soil 2; one end of the three-way valve 5 is connected to the gas pipeline 4, and the other two ends are respectively connected to the pressure sensing unit 3b and the charging unit; the charging unit includes a hose 6, a pressure gauge 7 and a charging valve 8, one end of the hose 6 is connected to the three-way valve 5, and the other end is connected to the charging valve 8, and the pressure gauge 7 is located on the hose 6; the temperature sensing unit 3a, the pressure sensing unit 3b and the atmospheric pressure sensing unit are all connected to the data acquisition and processing unit, and the data acquisition and processing unit is connected to the back-end platform through the data transmission unit; The present invention measures the temperature by burying the temperature measuring unit 3a close to the gas pipeline 4, so as to obtain the temperature inside the gas pipeline 4 more accurately, thereby improving the accuracy of subsequent air tightness detection.

[0024] Specifically, the temperature sensing unit 3a is connected to the main body of the air tightness detection device 3 (meter head 3) in a split type and is connected to the main body of the device through a cable. During air tightness detection, the temperature sensing unit 3a is close to the outer wall of the gas pipeline 4 and is placed in the buried soil 2; both the temperature sensing unit 3a and the pressure sensing unit 3b are digital outputs, which can reduce the impact of external interference on the output; the pressure sensing unit 3b is directly connected to the main body of the device through mechanical connections such as threads or flanges; Specifically, the data acquisition processing unit can issue instructions to start temperature and pressure data acquisition; is used to receive temperature and pressure acquisition data; can convert the temperature and pressure measurement values ​​into gas standard state equations by executing a program; can find the minimum value of different conversion values ​​within the test interval by executing a program; can use bubble sorting or Hill sorting methods to find the minimum value of conversion value points at different points; can set a specific acquisition time interval, which should be ≤1h; Specifically, the data transmission unit can transmit the temperature, pressure and other parameters collected in real time to the back-end platform; it can transmit the conversion values ​​of different collection points, the minimum values ​​of different conversion values, the final corrected pressure drop and other information to the back-end platform; when the corrected pressure drop meets or does not meet the requirements, the data transmission unit can send the detection qualified or unqualified alarm information issued by the data acquisition and processing unit to the back-end platform.

[0025] The device and method for detecting gas tightness of a gas pipeline of the present invention measure parameters such as temperature and pressure inside and outside the gas pipeline 4, perform intelligent judgment and conversion, make the measurement results closer to the on-site use environment, and upload the data remotely, reduce labor costs and human error operations, make the data more real and reliable, and improve detection efficiency.

[0026] Compared with the traditional electronic pressure gauge, the detection device of the present invention can realize remote air tightness detection, greatly improve the test efficiency, reduce the labor cost and misoperation of personnel; the pipeline air tightness detection device adopts wireless transmission technology, automatically uploads pressure data, can realize remote air tightness detection, greatly improve the test efficiency, reduce the labor cost and misoperation of personnel; The embodiment of the present invention further provides a detection method based on the gas pipeline air tightness detection device as described above, comprising the steps of: Open the on-off valve 8 and the three-way valve 5 to connect the gas pipeline 4 with the hose 6, pressurize the gas pipeline 4, and after the required pressure value is reached in the gas pipeline 4 by observing the pressure gauge 7, close the on-off valve 8; Install the air tightness detection device 3 so that its temperature sensing unit 3a is close to the outer wall of the gas pipeline 4, open the three-way valve 5 to disconnect the gas pipeline 4 from the hose 6 and connect it to the pressure sensing unit 3b of the air tightness detection device 3; Backfill the soil 2 so that it is nearly level with the ground 1; The airtightness detection device 3 first works stably for 1 to 2 hours, and the test data during this period is not used; like Figure 2 As shown, initially, the test value of the temperature sensing unit 3a is T1, the test value of the pressure sensing unit 3b is H1, and the test value of the atmospheric pressure sensing unit is B1; the test value is set H 1 is the base value, such as Figure 2 As shown. In the test interval, assuming that at a certain moment, the test value of the temperature sensor unit 3a is T2, the test value of the pressure sensor unit 3b is H2, and the test value of the atmospheric pressure sensor unit is B2; Corrected pressure drop, the specific formula is:

[0027]

[0028] in, H 1. H 2 is the measured value of the pressure in the pipeline at the beginning and end of the air tightness test. B 1. B 2 is the atmospheric pressure measurement value at the beginning and end of the airtightness test. T 1. T 2 is the temperature measurement value in the pipeline at the beginning and end of the air tightness test; is the converted value; Set the initial pressure sensor unit 3b test value H1 as the reference value; the test interval is 24h to 30h; find the minimum conversion value within the test interval, specifically: assume that the acquisition time mark points within the interval are 1,...,n (n is an integer, n>1), and find the minimum conversion value within the test interval through bubble sort or shell sort ; Corrected pressure drop ,satisfy It indicates that the air tightness test is passed.

[0029] The gas pipeline air tightness detection device in the present invention measures the temperature and pressure of the gas inside the gas pipeline 4 and the external atmospheric pressure value over a period of time, and determines whether the pressure change inside the gas pipeline 4 is within the corrected pressure drop range by converting the gas standard state equation, thereby determining whether the gas pipeline 4 meets the air tightness requirements.

[0030] Compared with the wireless remote gas pipeline air tightness detection equipment on the market, the present invention measures the temperature of the outer wall of the pipeline while measuring the pressure in the pipeline, which can reduce the influence of external environment such as sunlight, rain, ice and snow, and reduce the temperature measurement error. In terms of detection method, the present invention uses bubble sorting or Hill sorting method to find the minimum value of each collection point in the test interval, and can simply judge whether the pipeline air tightness meets the requirements by comparing the corrected pressure drop only once.

[0031] The above are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should be regarded as the protection scope of the present invention.

Claims

1. A gas pipeline air tightness detection device, It is characterized in that The invention comprises a charging unit, a temperature sensing unit (3a), a pressure sensing unit (3b), a three-way valve (5), an atmospheric pressure sensing unit, a data acquisition processing unit, a data transmission unit and a power module; the temperature sensing unit (3a) is closely attached to the outer wall of the gas pipeline (4) and is placed in the buried soil; one end of the three-way valve (5) is connected to the gas pipeline (4), and the other two ends are respectively connected to the pressure sensing unit (3b) and the charging unit; the temperature sensing unit (3a), the pressure sensing unit (3b) and the atmospheric pressure sensing unit are all connected to the data acquisition processing unit, and the data acquisition processing unit is connected to the back-end platform via the data transmission unit.

2. The gas pipeline air tightness detection device according to claim 1, It is characterized in that The charging unit comprises a hose (6), a pressure gauge (7) and an air charging valve (8); one end of the hose (6) is connected to the three-way valve (5), and the other end is connected to the air charging valve (8); the pressure gauge (7) is located on the hose (6).

3. The gas pipeline air tightness detection device according to claim 1, It is characterized in that The atmospheric pressure sensing unit, the data acquisition and processing unit, the data transmission unit and the power supply module are all built into a meter head (3) of the detection device.

4. The gas pipeline air tightness detection device according to claim 1, 2 or 3, It is characterized in that The temperature sensing unit (3a) is detachably connected to the meter head (3) of the detection device via a cable.

5. The gas pipeline air tightness detection device according to claim 1, 2 or 3, It is characterized in that The pressure sensing unit (3b) is directly connected to the gauge head (3) of the detection device via a thread or a flange.

6. A detection method based on the gas pipeline air tightness detection device according to any one of claims 1 to 5, It is characterized in that Includes steps: Open the three-way valve (5) to connect the gas pipeline (4) to the pressure charging unit, and after the pressure in the gas pipeline (4) reaches a preset pressure value through the pressure charging unit, close the pressure charging unit; Opening the three-way valve (5) disconnects the gas pipeline (4) from the pressure charging unit and connects it to the pressure sensing unit (3b); The air tightness detection device should work stably for a certain period of time, and the test data during this period will not be used; Initially, the test value of the temperature sensing unit (3a) is T 1 , the test value of the pressure sensing unit (3b) is H 1 And the atmospheric pressure sensor unit test value is B 1 ; Set the test value H 1 is the base value; In the test range, the minimum conversion value in the test range is sought to obtain the corrected pressure drop; if the corrected pressure drop is less than the preset value, it indicates that the air tightness test is qualified.

7. The detection method according to claim 6, It is characterized in that The conversion value is specifically: in, H 1 , H 2 It is the measured value of the pressure in the pipeline at the beginning and end of the air tightness test. B 1 , B 2 It is the atmospheric pressure measurement value at the beginning and end of the airtightness test. T 1 , T 2 The temperature measurement value inside the pipeline at the beginning and end of the air tightness test; is the converted value.

8. The detection method according to claim 7, It is characterized in that Corrected pressure drop .

9. The detection method according to claim 6, 7 or 8, It is characterized in that The test period is 24h to 30h.

10. The detection method according to claim 6, 7 or 8, It is characterized in that Use bubble sort or shell sort to find the minimum conversion value in the test interval , n is an integer and n>1.

Images