Online purging device for large-pipe-diameter dirty and wet gas flowmeter

Abstract

The utility model discloses an on-line purging device for a large-pipe-diameter dirty and wet gas flowmeter, which comprises a gas pipeline, a flowmeter is arranged in the gas pipeline, at least one purging pipe is arranged on the gas pipeline at the downstream of the flowmeter, a purging valve is arranged on each purging pipe, and the outer end of each purging pipe is connected to a steam source through a steam header pipe; the purging pipe is obliquely arranged, so that steam flows towards the upstream along a spiral track in the gas pipeline; according to the utility model, on-line purging of the flowmeter in the pipeline is realized, and impurities attached to the flowmeter are removed, so that the precision of flow detection is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of industrial gas pipeline flow detection, in particular to an online purge device for a dirty and wet gas flow meter with a large pipe diameter. Background Art

[0002] In the production process of some industrial production lines, a large amount of gas is often generated, such as blast furnace gas produced by iron smelting blast furnaces and coke oven gas produced by coke ovens. These gases are by-products in the production process and are fuels required for downstream production processes. They have high economic utilization value. Flow measurement is the basis for settlement in the process of gas transmission. Accurate and stable measurement data is crucial. Gas flow measurement, especially for large pipes with a diameter of more than 500mm, generally uses a differential pressure flowmeter;

[0003] The differential pressure flowmeter is installed directly on the pipeline and needs to be in real-time contact with the fluid medium. However, the gas medium is often dirty and wet gas, mixed with certain specific impurities, such as dust in blast furnace gas and tar in coke oven gas. When the impurities flow through the flowmeter, they will adhere to the flowmeter body and the pipe wall of the pipeline, causing the throttling device of the flowmeter and the pipe wall structure to change, resulting in abnormal flow measurement data. Therefore, the flowmeter needs to be cleaned of impurities regularly. However, due to the complex process of gas outage in large pipelines and the large workload of disassembling and maintaining flowmeters, it is often difficult to clean the flowmeter and the pipe wall. The flow measurement error caused by dirty and wet gas impurities can only be corrected by data correction, and its accuracy and data credibility are difficult to guarantee. Utility Model Content

[0004] The utility model aims to solve the problems raised in the above-mentioned background technology and to provide an online purge device for a dirty and wet gas flow meter with a large pipe diameter.

[0005] The specific technical scheme of the utility model is as follows: an online purge device for a large-diameter dirty and wet gas flowmeter, comprising a gas pipeline, a flowmeter being installed in the gas pipeline, at least one purge pipe being installed on the gas pipeline downstream of the flowmeter, each purge pipe being equipped with a purge valve, and the outer end of the purge pipe being connected to a steam source through a steam main pipe; the purge pipe is arranged at an angle so that the steam flows upstream along a spiral trajectory in the gas pipeline.

[0006] Preferably, the flowmeter adopts a V-cone flowmeter, a low-pressure pressure port is provided on the pipe wall of the gas pipeline, the low-pressure pressure port is connected with the V-cone flowmeter, a high-pressure pressure port is provided upstream of the low-pressure pressure port, both the low-pressure pressure port and the high-pressure pressure port are equipped with a primary valve, the outer ends of the low-pressure pressure port and the high-pressure pressure port are provided with pressure guiding pipes, the outer ends of the two pressure guiding pipes are connected with a connecting pipe, and a balancing valve is installed on the connecting pipe; the two pressure guiding pipes are commonly connected to the differential pressure transmitter and are both equipped with secondary valves.

[0007] Preferably, the outer ends of all the purge pipes are connected to a purge main pipe, the purge main pipe is connected to a steam main pipe, and a steam valve A is installed on the purge main pipe.

[0008] Preferably, one end of the connecting pipe is connected to the steam main pipe and is equipped with a steam valve B.

[0009] Preferably, a steam trap is installed at the lowest point of the steam main pipe.

[0010] Preferably, a drain valve is installed at the lowest point of the pressure guiding pipe.

[0011] The beneficial effects of the utility model are as follows: the flow meter in the pipeline can be purged online to remove impurities attached to the flow meter, thereby ensuring the accuracy of flow detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of the utility model;

[0013] Figure 2 It is a cross-sectional view of the utility model gas pipeline;

[0014] Figure 3 yes Figure 2 AA view;

[0015] In the figure: 1. Gas pipeline; 2. High-pressure pressure port; 3. Low-pressure pressure port; 4. V-cone flowmeter; 5. Purge pipe; 6. Purge valve; 7. Steam valve A; 8. Steam valve B; 9. Balancing valve; 10. Pressure pipe; 11. Primary valve; 12. Secondary valve; 13. Differential pressure transmitter; 14. Drain valve; 15. Steam trap; 16. Steam main valve. DETAILED DESCRIPTION

[0016] See also Figure 1-3This embodiment provides an online purging device for a large diameter dirty and wet gas flowmeter, comprising a gas pipeline 1, a flowmeter installed in the gas pipeline 1, two purge pipes 5 installed on the gas pipeline 1 downstream of the flowmeter, the distance between the purge pipe 5 and the flowmeter is approximately the diameter of the gas pipeline 1, each purge pipe 5 is equipped with a purge valve 6, the outer end of the purge pipe 5 is connected to a steam source through a steam main pipe, the steam temperature is ≥100°C, and the pressure is in the range of 0.6-1.0MPa; the purge pipe 5 is arranged obliquely so that the steam flows upstream along a spiral trajectory in the gas pipeline 1, thereby having a better purge effect; specifically, the purge pipe 5 is arranged at an angle of 40°-60° with the radial direction of the gas pipeline 1, and the purge pipe 5 is arranged at an angle of 30°-60° with the axis of the gas pipeline 1, and the two purge pipes 5 are arranged on both sides of the gas pipeline 1. Steam has a good removal effect on impurities such as dust and tar in dirty and wet gas. Preferably, the flow meter adopts a V-cone flow meter 4, a low-pressure port 3 is provided on the pipe wall of the gas pipeline 1, the low-pressure port 3 is connected to the V-cone flow meter 4, a high-pressure port 2 is provided upstream of the low-pressure port 3, and both the low-pressure port 3 and the high-pressure port 2 are equipped with a primary valve 11, and the outer ends of the low-pressure port 3 and the high-pressure port 2 are both provided with a pressure pipe 10, and the outer ends of the two pressure pipes 10 are connected to a connecting pipe, and the connecting pipe is equipped with a balancing valve 9; the two pressure pipes 10 are connected to the differential pressure transmitter 13 and are equipped with a secondary valve 12. Preferably, the outer ends of all purge pipes 5 are connected to a purge main pipe, and the purge main pipe is connected to the steam main pipe, and the purge main pipe is equipped with a steam valve A7.

[0017] Preferably, one end of the connecting pipe is connected to the steam main pipe and is equipped with a steam valve B8.

[0018] Preferably, a steam trap 15 is installed at the lowest point of the steam main.

[0019] Preferably, a drain valve 14 is installed at the lowest point of the pressure pipe 10. The working principle of the utility model is as follows: in the normal measurement mode: the steam main valve 16, the steam trap 15, the steam valve A7, the steam valve B8, the purge valve 6, the balance valve 9, and the drain valve 14 are all in the closed state, and the primary valve 11 and the secondary valve 12 of the differential pressure measurement pipeline are in the open state.

[0020] When it is necessary to purge the pressure pipe 10, follow the following sequence: open the steam main valve 16 → open the steam trap 15 to drain the water and then close the steam trap 15 → close the two secondary valves 12 → close the two primary valves 11 → open the balancing valve 9 → open the steam valve B8 → open the two drain valves 14 → purge for 2 minutes. After there is no impurity at the bottom of the drain valve 14 and the steam is flowing smoothly, close the steam main valve 16 → close the steam valve B8 → close the two drain valves 14 → open the two primary valves 11 → open the two secondary valves 12 → close the balancing valve 9 → enter the normal measurement mode. When the pressure port needs to be purged, follow the following sequence: open the steam main valve 16 → open the steam trap 15 to drain the water and then close the steam trap 15 → close the two secondary valves 12 → open the balancing valve 9 → open the steam valve B8 → purge for 3 minutes → close the steam main valve 16 → close the steam valve B8 → open the two sewage valves 14 until there is no water discharged from the lower part of the sewage valve 14, close the two sewage valves 14 → open the two secondary valves 12 → close the balancing valve 9 → enter the normal measurement mode. When the flow meter body and pipeline need to be purged, follow the following sequence: open the steam main valve 16 → open the steam trap 15 to drain the water and then close the steam trap 15 → close the two primary valves 11 → open the purge valve 6 → open the steam valve A7 → purge for 5 minutes → close the steam main valve 16 → close the steam valve A7 → close the purge valve 6 → open the two primary valves 11 → enter the normal measurement mode. The time and frequency of purging the flow meter body, the pressure pipe 10, and the pressure tapping port can be appropriately adjusted according to the amount of impurities in the dirty and wet gas on site. If there are many impurities, the purging time can be appropriately extended and the purging frequency can be increased. The purging device of the utility model can realize online cleaning of the flow meter and pipeline, thereby maintaining the accuracy of flow meter detection for a long time without stopping production for maintenance.

Claims

1. An online purge device for a large diameter dirty and wet gas flow meter, comprising a gas pipeline, in which a flow meter is installed, characterized in that: At least one purge pipe is installed on the gas pipeline downstream of the flow meter, each purge pipe is equipped with a purge valve, and the outer end of the purge pipe is connected to the steam source through the steam main pipe; the purge pipe is arranged obliquely so that the steam flows upstream along a spiral trajectory in the gas pipeline.

2. The online purge device for a large diameter dirty and wet gas flow meter according to claim 1, characterized in that: The flow meter adopts a V-cone flow meter, a low-pressure pressure port is provided on the pipe wall of the gas pipeline, the low-pressure pressure port is connected with the V-cone flow meter, a high-pressure pressure port is provided upstream of the low-pressure pressure port, both the low-pressure pressure port and the high-pressure pressure port are equipped with a primary valve, the outer ends of the low-pressure pressure port and the high-pressure pressure port are both equipped with pressure pipes, the outer ends of the two pressure pipes are connected with a connecting pipe, and the connecting pipe is equipped with a balancing valve; the two pressure pipes are commonly connected to the differential pressure transmitter and are both equipped with secondary valves.

3. The online purge device for a large diameter dirty and wet gas flow meter according to claim 2, characterized in that: The outer ends of all the purge pipes are connected to a purge main pipe, which is connected to a steam main pipe, on which a steam valve A is installed.

4. The online purge device for a large diameter dirty and wet gas flow meter according to claim 3, characterized in that: One end of the connecting pipe is connected to the steam main pipe and is equipped with a steam valve B.

5. The online purge device for a large diameter dirty and wet gas flow meter according to claim 1, characterized in that: A steam trap is installed at the lowest point of the steam main pipe.

6. The online purge device for a large diameter dirty and wet gas flow meter according to claim 2, characterized in that: A drain valve is arranged at the lowest point of the pressure guiding pipe.

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