Pressure monitoring device and method for gas pipeline maintenance operation

Abstract

The pressure monitoring device for gas pipeline maintenance operation comprises a first liquid container with an upward opening, a first adjusting pipeline is installed in the first liquid container in a penetrating mode, and a first ball valve and a second ball valve are installed at the upper end and the lower end of the first adjusting pipeline correspondingly; a second liquid container with a downward opening is installed in the middle of the first adjusting pipeline, an exhaust hole is formed in the middle of the first adjusting pipeline and located in the second liquid container, a liquid outlet is formed in the bottom of the first liquid container, and the initial pressure value of the pipe network is set and adjusted by adding water at different liquid levels into the first liquid container. The invention further provides a monitoring method of the pressure monitoring device for the gas pipeline maintenance operation. The pressure monitoring process is visual, pressure reduction or rise is visual (liquid level and bubbles), and errors are not prone to occurring; when the pressure rises, automatic discharge can be realized, so that the operation is safer; by means of the device, a pipe network is isolated from air, and air is not prone to mixing.

Description

Technical Field

[0001] The present invention relates to the technical field of gas pipeline maintenance, and particularly relates to a pressure monitoring device and method for gas pipeline maintenance operations. Background Art

[0002] In gas pipeline maintenance operations, after closing the valve to stop the gas supply and discharging and reducing the pressure, the maintenance pipe section usually needs to maintain a slightly positive pressure (300 - 800 Pa). One is to provide a suitable pressure for the hot work operation, and the other is that the slightly positive pressure can prevent air from entering the pipeline to form a mixed gas.

[0003] After the pressure regulation is completed, the valve of the blow-off pipe is closed to maintain the pressure. However, due to possible internal leakage faults of the buried pipe valve, gas slowly leaks from the high-pressure end to the stopped gas pipe section, causing the pressure to gradually increase. This will pose a greater safety risk to the maintenance operation. Therefore, it is necessary to monitor the pressure and maintain a slightly positive pressure (300 - 800 Pa). If the pressure is found to increase, the valve of the blow-off pipe needs to be opened for exhaust. If the pressure is found to decrease, the bypass valve needs to be opened for gas passing.

[0004] Currently, this kind of pressure monitoring usually relies on the experience of the operator, using "hand feeling" to judge the pressure magnitude. The blow-off pipe valve is opened every few minutes, and the hand is placed above to feel the air flow height to judge the pressure. This method has the following disadvantages: 1. Judging the pressure magnitude by "hand feeling" is not intuitive and is prone to misjudgment; 2. When the pressure increases, it is only when the blow-off pipe valve is opened to "feel" the pressure that it is discovered and discharged, and automatic discharge cannot be achieved; 3. Frequently opening the blow-off pipe valve may cause air to be sucked back into the pipeline through the blow-off pipe during the operation process, forming a mixed gas and causing risks. Summary of the Invention

[0005] To solve the above problems, the present invention aims to propose a pressure monitoring device and method for gas pipeline maintenance operations, realizing an intuitive pressure monitoring process, visualizing the decrease or increase of pressure (liquid level, bubbles), and being not prone to errors; automatically discharging when the pressure increases, making the operation safer; and isolating the pipe network from the air and not being easily mixed with air.

[0006] To achieve the above object, the technical solution of the present invention is realized as follows:

[0007] A pressure monitoring device for gas pipeline maintenance operations, including a first liquid container with an upward opening. A first adjustment pipeline is installed through the first liquid container. A first ball valve and a second ball valve are respectively installed at the upper and lower ends of the first adjustment pipeline. A second liquid container with a downward opening is installed at the middle position of the first adjustment pipeline. An exhaust hole is provided in the middle of the first adjustment pipeline, and the exhaust hole is located inside the second liquid container. A liquid discharge port is provided at the bottom of the first liquid container. The initial pressure value of the adjustment pipeline network is set by adding water with different liquid levels in the first liquid container.

[0008] Further, both the first liquid container and the second liquid container are made of transparent plastic or transparent glass.

[0009] Further, scales are provided on both the first liquid container and the second liquid container.

[0010] Further, the first liquid container, the first adjustment pipeline, and the second liquid container are integrally formed.

[0011] Further, a ball valve is installed in the liquid discharge port.

[0012] Further, the first liquid container, the first adjustment pipeline, and the second liquid container are all vertically arranged.

[0013] To achieve the above object, the present invention also provides a monitoring method for a pressure monitoring device for gas pipeline maintenance operations, including the following steps:

[0014] S1: Install the pressure monitoring device at the upper end of the blow-off pipe and connect it through the second ball valve.

[0015] S2: Open the first ball valve and the second ball valve. At this time, normal blowing-off can be carried out, and exhaust pressure regulation can be performed.

[0016] S3: When the appropriate pressure is adjusted, that is, 300 - 800 Pa, close the first ball valve, add water to the first liquid container to form a seal; at this time, observe the scale, and the water can be discharged through the liquid discharge port to adjust to the appropriate liquid level; set the maximum allowable pressure of the pipeline network until the liquid level difference between the inside and outside of the container is 3 cm - 8 cm. At this time, it indicates that the pipeline pressure is normal.

[0017] S4: Observe the change of the liquid level difference to judge the change of the pipeline network pressure; if the liquid level difference decreases, open the bypass valve to let gas pass through to increase the pressure; if the liquid level difference increases, when it exceeds the set maximum liquid level difference, at this time the gas will overcome the hydraulic pressure and discharge outwards, that is, bubbles are observed. This process is automatically adjusted to ensure the maximum pressure of the pipeline network and will not overpressure; if a large number of bubbles are observed, even splashing, at this time, the first ball valve needs to be opened for discharge.

[0018] Beneficial effects: The pressure monitoring process of the present invention is intuitive, and the decrease or increase of pressure is visualized (liquid level, bubbles), making it not easy to make mistakes; when the pressure increases, it can be automatically discharged, making the operation safer; the device of the present invention isolates the pipe network from the air and is not easy to mix air. Brief Description of the Drawings

[0019] The drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0020] Figure 1 It is a schematic structural diagram of the pressure monitoring device for gas pipeline maintenance operations described in the embodiment of the present invention;

[0021] Figure 2 It is a schematic diagram of adding liquid level water during the adjustment process of the pressure monitoring device for gas pipeline maintenance operations described in the embodiment of the present invention;

[0022] Figure 3 It is a schematic diagram of the working principle of the pressure monitoring device for gas pipeline maintenance operations described in the embodiment of the present invention. Detailed Embodiments

[0023] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the drawings and in combination with the embodiments.

[0024] Embodiment 1

[0025] See Figures 1 - 3 : A pressure monitoring device for gas pipeline maintenance operations, including a first liquid container 1 with an upward opening. A first adjustment pipe 2 is installed through the first liquid container 1. A first ball valve 201 and a second ball valve 202 are respectively installed at the upper and lower ends of the first adjustment pipe 2. A second liquid container 3 with a downward opening is installed at the middle position of the first adjustment pipe 2. An exhaust hole 203 is provided in the middle of the first adjustment pipe 2, and the exhaust hole 203 is located inside the second liquid container 3. A liquid discharge port 101 is provided at the bottom of the first liquid container 1. The initial pressure value of the pipe network is set by adding water with different liquid levels in the first liquid container 1.

[0026] In this embodiment, the second ball valve is installed at the upper end of the relief pipe. The change of the pipe network pressure can be judged by observing the change of the liquid level difference; if the liquid level difference decreases, the bypass valve is opened to let gas pass through to increase the pressure; if the liquid level difference increases and exceeds the set maximum liquid level difference, at this time the gas will overcome the hydraulic pressure and discharge, that is, bubbles are observed. This process is automatically adjusted to ensure the maximum pressure of the pipe network and will not overpressure; if a large number of bubbles are observed, even splashing, at this time the first ball valve needs to be opened for discharge.

[0027] In addition to being used for overpressure relief, this embodiment can also perform active relief emissions and has a pressure monitoring function. When abnormal pressure is detected, measures can be taken in a timely manner.

[0028] In a specific example, both the first liquid container 1 and the second liquid container 2 are made of transparent plastic or transparent glass.

[0029] Since the first liquid container and the second liquid container of this embodiment are both made of transparent plastic or transparent glass, it is convenient for maintenance personnel to observe the internal and external liquid level differences between the first liquid container and the second liquid container.

[0030] In a specific example, scales 4 are provided on both the first liquid container 1 and the second liquid container 2.

[0031] When the pipe network is adjusted to the appropriate pressure (300 - 800 Pa), close the first ball valve and add water to the first liquid container to form a seal; at this time, observe the scale, and the liquid level difference (3 cm - 8 cm) between the inside and outside of the container indicates that the pipeline pressure is normal.

[0032] It should be noted that the appropriate pressure for each operation varies according to the pipeline length and pipe diameter, and on-site adjustment and judgment are required. During the gas passing stage, maintenance personnel need to judge according to the flame height at the downstream operation position. When the flame height is appropriate, it means that it has been adjusted to the appropriate pressure, that is, 300 - 800 Pa. At this time, add water to seal according to this pressure value and control the liquid height.

[0033] In a specific example, the first liquid container 1, the first adjustment pipeline 2, and the second liquid container 3 are integrally formed.

[0034] In a specific example, a ball valve is installed in the drain port 101.

[0035] This embodiment can discharge water through the ball valve of the drain port, adjust to the appropriate liquid level, and can set the maximum allowable pressure of the pipe network.

[0036] In a specific example, the first liquid container 1, the first adjustment pipeline 2, and the second liquid container 3 are all vertically arranged.

[0037] To achieve the above object, the present invention also provides a monitoring method for a pressure monitoring device for gas pipeline maintenance operations, including the following steps:

[0038] S1: Install the pressure monitoring device at the upper end of the relief pipe and connect it through the second ball valve 202;

[0039] S2: Open the first ball valve 201 and the second ball valve 202. At this time, normal relief can be carried out and exhaust pressure regulation can be performed.

[0040] S3: When the pressure is adjusted to the appropriate value, i.e., 300 - 800 Pa, close the first ball valve 201, add water to the first liquid container 1 to form a seal; at this time, observe the scale 4 and drain water through the drain port 101 to adjust to the appropriate liquid level; set the maximum allowable pressure of the pipe network until the liquid level difference between the inside and outside of the container is 3 cm - 8 cm, which indicates that the pipe pressure is normal at this time.

[0041] S4: Observe the change in the liquid level difference to judge the change in the pipe network pressure; if the liquid level difference decreases, open the bypass valve to let air through to increase the pressure; if the liquid level difference increases and exceeds the set maximum liquid level difference, at this time the gas will overcome the hydraulic pressure and discharge outwards, that is, bubbles are observed, and this process is automatically adjusted to ensure the maximum pressure of the pipe network and will not overpressure; if a large number of bubbles are observed, even splashing, at this time, the first ball valve 201 needs to be opened for discharge.

[0042] In summary, the pressure monitoring process of this embodiment is intuitive, and the decrease or increase of pressure is visualized (liquid level, bubbles), which is not easy to make mistakes; when the pressure increases, it can be automatically discharged, making the operation safer; the device of this embodiment isolates the pipe network from the air and is not easy to mix in air.

[0043] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A pressure monitoring device for gas pipeline maintenance operations, characterized in that: The invention comprises a first liquid container (1) with an opening facing upwards, a first regulating pipe (2) being installed through the first liquid container (1), a first ball valve (201) and a second ball valve (202) being installed at the upper and lower ends of the first regulating pipe (2), a second liquid container (3) with an opening facing downwards being installed in the middle of the first regulating pipe (2), a vent hole (203) being provided in the middle of the first regulating pipe (2), the vent hole (203) being located in the second liquid container (3), a liquid discharge port (101) being provided at the bottom of the first liquid container (1), and the initial pressure value of the regulating pipe network being set by adding water of different liquid levels in the first liquid container (1).

2. The pressure monitoring device for gas pipeline maintenance work according to claim 1, characterized in that: The first liquid container (1) and the second liquid container (2) are both transparent plastic or transparent glass containers.

3. The pressure monitoring device for gas pipeline maintenance work according to claim 2 is characterized in that: The first liquid container (1) and the second liquid container (2) are both provided with scales (4).

4. The pressure monitoring device for gas pipeline maintenance work according to claim 1, characterized in that: The first liquid container (1), the first regulating pipe (2) and the second liquid container (3) are all integrally formed.

5. The pressure monitoring device for gas pipeline maintenance work according to claim 1, characterized in that: A ball valve is installed in the liquid discharge port (101).

6. The pressure monitoring device for gas pipeline maintenance work according to claim 1, characterized in that: The first liquid container (1), the first regulating pipe (2) and the second liquid container (3) are all arranged vertically.

7. A monitoring method for a pressure monitoring device for a gas pipeline maintenance operation according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1: Install the pressure monitoring device on the upper end of the discharge pipe and connect it through the second ball valve (202); S2: Open the first ball valve (201) and the second ball valve (202), and then normal exhaust and pressure regulation can be performed; S3: When the pressure is adjusted to a suitable level, i.e., 300-800Pa, the first ball valve (201) is closed and water is added to the first liquid container (1) to form a seal; at this time, the scale (4) is observed and water can be drained through the drain port (101) to adjust the liquid level to a suitable level; the maximum allowable pressure of the pipe network is set until the liquid level difference between the inner and outer parts of the container is 3cm-8cm, which indicates that the pipe pressure is normal; S4: The change in the pipeline network pressure can be determined by observing the change in the liquid level difference; if the liquid level difference decreases, the bypass valve is opened to pass gas and increase the pressure; if the liquid level difference increases, when it exceeds the set maximum liquid level difference, the gas will overcome the hydraulic pressure and be discharged, that is, bubbles are observed. The process is automatically adjusted to ensure the maximum pressure of the pipeline network and prevent overpressure; if a lot of bubbles are observed, even splashing, it is necessary to open the first ball valve (201) to discharge.

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