Ash-deposition-resistant air volume measuring device for vertical pipeline

Abstract

The utility model relates to the technical field of gas flow measurement, in particular to an anti-dust-deposition air volume measuring device for a vertical pipeline, which comprises a differential pressure generating cylinder, a negative pressure outlet pipe and a positive pressure outlet pipe, and the inner bottom surface of the positive pressure outlet pipe and the inner bottom surface of the differential pressure generating cylinder are positioned on the same plane. The positive pressure outlet pipe and the negative pressure outlet pipe are internally provided with free swing components for automatically cleaning ash on the positive pressure tapping opening and the negative pressure tapping opening respectively, the inner bottom face of the differential pressure generating cylinder is obliquely arranged, the ash discharging opening is located at the lowest position of the inner bottom face, and the positive pressure tapping opening is located at the highest position of the inner bottom face. According to the utility model, the inside is not easy to accumulate dust and block, the maintenance workload is reduced, the problems that the output differential pressure generated at a low flow speed is small and the flow detection precision cannot be ensured when the unit load is low are solved, and the device can be used for measuring a large-section vertical pipeline.

Description

Technical Field

[0001] The utility model relates to the technical field of gas flow measurement, in particular to a vertical pipeline dust accumulation resistance air volume measurement device. Background Art

[0002] At present, there are many types of devices used for gas flow measurement in China, mainly including: wing type, Venturi type, Annubar type, multi-point backrest tube type, etc. Each device has its own advantages and disadvantages, but in vertical pipes, especially when the airflow is from top to bottom, the dusty airflow will cause dust accumulation and blockage inside the gas flow measurement.

[0003] Therefore, the measuring device needs to be purged regularly and irregularly, which increases the maintenance workload for the staff. In addition, the output differential pressure generated by the existing measuring device at low flow rates is small, and the accuracy cannot be guaranteed when the unit load is low. Utility Model Content

[0004] The utility model aims to solve the above defects and provides a vertical duct anti-dust accumulation air volume measuring device.

[0005] In order to overcome the defects existing in the background technology, the technical solution adopted by the utility model to solve its technical problems is: a vertical pipeline anti-dust accumulation air volume measurement device, including a differential pressure generating cylinder, the upper end of the differential pressure generating cylinder is provided with a windward opening facing the dust-containing airflow so that the dust-containing airflow enters the differential pressure generating cylinder, the bottom side is provided with an ash discharge port for discharging the dust-containing airflow, a negative pressure outlet pipe is vertically arranged on the outer side of the differential pressure generating cylinder, and the negative pressure taking port at the lower end of the negative pressure outlet pipe is located above the ash discharge port and close to the ash discharge port;

[0006] A positive pressure outlet pipe is vertically arranged on the outer side of the differential pressure generating tube, and the bottom side of the positive pressure outlet pipe is connected to the differential pressure generating tube by opening a positive pressure tapping port, and the inner bottom surface of the positive pressure outlet pipe and the inner bottom surface of the differential pressure generating tube are located on the same plane;

[0007] The positive pressure outlet pipe and the negative pressure outlet pipe are respectively provided with free swinging components for automatically cleaning the positive pressure tapping port and the negative pressure tapping port. The inner bottom surface of the differential pressure generating cylinder is inclined, and the dust discharge port is located at the lowest position of the inner bottom surface, and the positive pressure tapping port is located at the highest position of the inner bottom surface.

[0008] A further improvement includes that the area of ​​the ash discharge port is smaller than the area of ​​the windward port.

[0009] A further improvement includes that the angle between the inner bottom surface of the differential pressure generating cylinder and the horizontal plane is between 40 degrees and 80 degrees.

[0010] A further improvement includes that the free swinging member includes a connecting portion and a cleaning rod respectively arranged in the negative pressure outlet pipe and the positive pressure outlet pipe, and the connecting portion is movably connected to the upper end of the cleaning rod.

[0011] A further improvement includes providing a plurality of differential pressure generating tubes and arranging them in a vertical pipe, the differential pressure generating tubes are on the same horizontal plane in the vertical pipe, a negative pressure uniform main pipe and a positive pressure uniform main pipe are arranged in the vertical pipe, the negative pressure uniform main pipe is connected in parallel with a plurality of negative pressure uniform branch pipes, the positive pressure uniform main pipe is connected in parallel with a plurality of positive pressure uniform branch pipes, the negative pressure uniform branch pipes are respectively connected in parallel with a plurality of negative pressure outlet pipes on the differential pressure generating tubes, and the positive pressure uniform branch pipes are respectively connected in parallel with a plurality of positive pressure outlet pipes on the differential pressure generating tubes.

[0012] Further improvements include that the angle between the negative pressure equalizing branch pipe and the horizontal plane is between 40 degrees and 80 degrees, and the angle between the positive pressure equalizing branch pipe and the horizontal plane is between 40 degrees and 80 degrees.

[0013] The beneficial effects of the utility model are as follows: the utility model adopts an inner bottom surface with an inclined structure, and the interior is not easy to be blocked by dust accumulation, thereby reducing the maintenance workload and solving the problems of small output differential pressure generated at low flow rate and inability to guarantee flow detection accuracy when the unit load is low; the dust cleaning rod can prevent dust from clogging the positive pressure taking port and the negative pressure taking port. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0015] Figure 1 This is a front view of the first embodiment of the utility model;

[0016] Figure 2 yes Figure 1 Middle DD section view;

[0017] Figure 3 This is a front view of the second embodiment of the utility model;

[0018] Figure 4 It is a right side view of the second embodiment of the utility model;

[0019] In the figure, 1-vertical pipeline, 2-negative pressure outlet pipe, 3-ash discharge port, 4-differential pressure generating cylinder, 5-negative pressure tapping port, 6-positive pressure outlet pipe, 7-windward port, 8-connecting part, 9-ash cleaning rod, 10-positive pressure tapping port, 11-negative pressure uniform branch pipe, 12-negative pressure uniform main pipe, 13-positive pressure uniform branch pipe, 14-positive pressure uniform main pipe. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. The embodiments in the basic utility model and all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] according to Figure 1 , Figure 2 As shown, a vertical duct anti-dust accumulation air volume measurement device comprises a differential pressure generating cylinder 4, which is placed in a vertical duct 1. The dust-laden airflow in the vertical duct 1 flows from top to bottom. The upper end of the differential pressure generating cylinder 4 is provided with a windward opening 7 facing the dust-laden airflow so that the dust-laden airflow enters the differential pressure generating cylinder 4. The bottom side is provided with an ash discharge port 3 for discharging the dust-laden airflow. The area of ​​the ash discharge port 3 is smaller than the area of ​​the windward opening 7, so that the ash discharge port 3 is convenient for the airflow to be ejected at a high speed. The ash discharge port 3 has the functions of exhausting and discharging dust. The cross section of the differential pressure generating cylinder 4 is square, preferably circular or polygonal.

[0022] The negative pressure outlet pipe 2 is vertically arranged on the outer side of the differential pressure generating tube 4, and the negative pressure tapping port 5 at the lower end of the negative pressure outlet pipe 2 is located above the ash discharge port 3 and close to the ash discharge port 3. The dust-laden airflow entering the differential pressure generating tube 4 is ejected at high speed through the ash discharge port 3, which will generate a pressure lower than the static pressure in the vertical pipe 1 at the ash discharge port 3. By taking the value of the pressure, a pressure difference 30% to 50% greater than the normal pressure difference can be obtained, thereby improving the detection accuracy of the device when the airflow in the vertical pipe 1 is at a low flow rate, solving the problem that the air volume measurement cannot be guaranteed when the unit is working at low load. The negative pressure outlet pipe 2 is led out to the outside of the vertical pipe 1 for detecting negative pressure;

[0023] The positive pressure outlet pipe 6 is vertically arranged on the outer side of the differential pressure generating tube 4. The bottom side of the positive pressure outlet pipe 6 and the differential pressure generating tube 4 are connected by opening a positive pressure tapping port 10. The inner bottom surface of the positive pressure outlet pipe 6 and the inner bottom surface of the differential pressure generating tube 4 are located on the same plane. The positive pressure outlet pipe 6 is led out to the outside of the vertical pipe 1 to detect the positive pressure in the differential pressure generating tube 4.

[0024] The positive pressure outlet pipe 6 and the negative pressure outlet pipe 2 are respectively provided with free swinging components for automatically cleaning the positive pressure port 10 and the negative pressure port 5, so as to avoid dust accumulation and blockage at the positive pressure port 10 and the negative pressure port 5. In this way, there is no need for regular blowing, which greatly reduces the maintenance workload. The cross-section of the positive pressure outlet pipe 6 and the negative pressure outlet pipe 2 is square, and is further preferably circular or polygonal.

[0025] The inner bottom surface of the differential pressure generating tube 4 is inclined, and the ash discharge port 3 is located at the lowest position of the inner bottom surface, and the positive pressure tapping port 10 is located at the highest position of the inner bottom surface. The inner bottom surface of the differential pressure generating tube 4 is directly opposite to the dust-containing airflow so that the dust-containing airflow entering the differential pressure generating tube 4 flows along the inner bottom surface and is discharged from the ash discharge port 3. Because the inner bottom surface of the positive pressure outlet pipe 6 and the inner bottom surface of the differential pressure generating tube 4 are located in the same plane, the inner bottom surface of the positive pressure outlet pipe 6 also presents an inclined structure, which is convenient for dust entering the positive pressure outlet pipe 6 to slide out under the action of gravity. This structure is beneficial to prevent dust accumulation in the differential pressure generating tube 4 and facilitates ash discharge.

[0026] The angle between the inner bottom surface of the differential pressure generating tube 4 and the horizontal plane is between 40 degrees and 80 degrees. The large inclination design is conducive to the ash discharge port 3 to discharge all dust, avoid dust accumulation in the differential pressure generating tube 4, avoid later purging, and reduce maintenance workload.

[0027] The free swinging component includes a connecting portion 8 and a cleaning rod 9 which are respectively arranged in the negative pressure outlet pipe 2 and the positive pressure outlet pipe 6. The connecting portion 8 is movably connected to the upper end of the cleaning rod 9. The cleaning rod 9 is affected by factors such as the disturbance of the airflow in the pipe and the vibration of the entire vertical pipe 1, and can swing back and forth freely and irregularly in the pipe, thereby achieving the effect of cleaning the pressure port and avoiding dust accumulation. The positive and negative pressure outlet pipes are perpendicular to the ground, and the dust in the positive and negative pressure outlet pipes can almost fall back into the vertical pipe 1 under the influence of gravity, so that the anti-dust accumulation performance of the entire device is greatly enhanced.

[0028] according to Figure 3 and Figure 4As shown, the differential pressure generating tubes 4 are provided in plurality and arranged in the vertical pipe 1. The differential pressure generating tubes 4 are on the same horizontal plane in the vertical pipe 1. The vertical pipe 1 is provided with a negative pressure uniform main pipe 12 and a positive pressure uniform main pipe 14. The negative pressure uniform main pipe 12 is connected in parallel with a plurality of negative pressure uniform branch pipes 11. The positive pressure uniform main pipe 14 is connected in parallel with a plurality of positive pressure uniform branch pipes 13. The negative pressure uniform branch pipes 11 are respectively connected in parallel with the negative pressure outlet pipes 2 on the differential pressure generating tubes 4. The positive pressure uniform branch pipes 13 are respectively connected in parallel with the positive pressure outlet pipes 6 on the differential pressure generating tubes 4. The positive pressure outlet pipes 6 of the differential pressure generating tubes 4 are connected in parallel with the positive pressure outlet pipes 6 of the differential pressure generating tubes 4. Together, by making the positive pressures measured by each other uniform inside, the average positive pressure of the differential pressure generating tube 4 can be obtained, which is connected in parallel by the negative pressure lead-out tube 2. The negative pressure lead-out tube 2 is output after being uniform. The total positive and negative pressure difference after output can be measured on a certain horizontal section of the vertical pipe 1 to obtain the average flow velocity of the airflow in the entire vertical pipe 1, thereby obtaining the air volume value. This structure is suitable for vertical pipes 1 with large cross-sections. By increasing the measuring points through multiple differential pressure generating tubes 4, the average flow velocity and flow rate of the airflow in the pipe can be accurately measured. This embodiment is mainly used to solve the problem of uneven airflow velocity field on the cross-section of large-section pipes. By arranging multiple measuring points, the average velocity is measured by this assembly to obtain the correct flow rate in the vertical pipe 1.

[0029] The angle between the negative pressure equalizing branch pipe 11 and the horizontal plane is between 40 degrees and 80 degrees, and the angle between the positive pressure equalizing branch pipe 13 and the horizontal plane is between 40 degrees and 80 degrees. This design method effectively avoids dust accumulation in the outlet pipe and the equalizing pipe, ensuring that the dust falls back into the differential pressure generating cylinder 4 under gravity and is discharged.

[0030] Working principle: The dust-laden airflow in the vertical pipe 1 blows vertically from top to bottom toward the differential pressure generating cylinder 4, and different differential pressures are formed on the inside and outside of the differential pressure generating cylinder 4. Since the windward area of ​​the upper end of the differential pressure generating cylinder 4 is much larger than the area of ​​the dust discharge port 3, a pressure higher than the static pressure in the vertical pipe 1 will be generated in the space inside the differential pressure generating cylinder 4, which is called "+" positive pressure. The positive pressure in the differential pressure generating cylinder 4 can be led out through the positive pressure tapping port 10;

[0031] A negative pressure outlet pipe 2 is arranged on the outer side of the differential pressure generating tube 4, and the dust-laden airflow in the differential pressure generating tube 4 is ejected from the ash discharge port 3. The ash discharge port 3 generates a pressure lower than the static pressure in the vertical pipe 1, which is called "-" negative pressure. The negative pressure tapping port 5 takes the value of the ash discharge port 3, and a differential pressure 30-50% greater than the normal differential pressure can be obtained. This invisibly greatly improves the measurement accuracy of the device and thoroughly solves the problem of insufficient accuracy in low-load operation. The cleaning rod 9 is suspended in the pressure taking pipe. Due to the disturbance of the airflow in the pipe and the vibration of the entire vertical pipe 1 and other factors, it can swing back and forth freely in the pipe without rules, thereby achieving the function of cleaning and avoiding the blockage of the negative pressure tapping port 5 and the positive pressure tapping port 10 due to dust accumulation;

[0032] The magnitude of the pressure difference between the inside and outside of each differential pressure generating cylinder 4 can reflect the magnitude of the wind speed passing therethrough. The greater the wind speed, the greater the differential pressure. Conversely, the smaller the wind speed, the smaller the pressure difference.

[0033] The experimental data are as follows:

[0034]

[0035] Note: The distance H in the above table refers to the distance from the negative pressure port 5 to the ash discharge port 3.

[0036] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A vertical duct anti-dust accumulation air volume measurement device, characterized in that: It comprises a differential pressure generating cylinder (4), wherein the upper end of the differential pressure generating cylinder (4) is provided with a windward opening (7) facing the dust-containing airflow so that the dust-containing airflow enters the differential pressure generating cylinder (4), and the bottom side is provided with an ash discharge opening (3) for discharging the dust-containing airflow; A negative pressure outlet pipe (2) is vertically arranged on the outer side of the differential pressure generating cylinder (4), and a negative pressure tapping port (5) at the lower end of the negative pressure outlet pipe (2) is located above the ash discharge port (3) and close to the ash discharge port (3); A positive pressure outlet pipe (6) is vertically arranged on the outer side surface of the differential pressure generating tube (4); the bottom side surface of the positive pressure outlet pipe (6) and the differential pressure generating tube (4) are connected by providing a positive pressure tapping port (10); the inner bottom surface of the positive pressure outlet pipe (6) and the inner bottom surface of the differential pressure generating tube (4) are located on the same plane; The positive pressure outlet pipe (6) and the negative pressure outlet pipe (2) are respectively provided with free swinging components for automatically cleaning the positive pressure tapping port (10) and the negative pressure tapping port (5); the inner bottom surface of the differential pressure generating cylinder (4) is inclined, and the dust discharge port (3) is located at the lowest position of the inner bottom surface, and the positive pressure tapping port (10) is located at the highest position of the inner bottom surface.

2. A vertical duct anti-dust accumulation air volume measurement device as claimed in claim 1, characterized in that: The area of ​​the ash discharge port (3) is smaller than the area of ​​the windward port (7).

3. A vertical duct anti-dust accumulation air volume measuring device as claimed in claim 2, characterized in that: The angle between the inner bottom surface of the differential pressure generating cylinder (4) and the horizontal plane is between 40 degrees and 80 degrees.

4. A vertical duct anti-dust accumulation air volume measuring device as claimed in claim 3, characterized in that: The free swinging component comprises a connecting portion (8) and a cleaning rod (9) respectively arranged in the negative pressure outlet pipe (2) and the positive pressure outlet pipe (6), wherein the connecting portion (8) is movably connected to the upper end of the cleaning rod (9).

5. A vertical duct anti-dust accumulation air volume measuring device according to any one of claims 1 to 4, characterized in that: A plurality of differential pressure generating tubes (4) are provided and arranged in the vertical pipe (1). The differential pressure generating tubes (4) are on the same horizontal plane in the vertical pipe (1). The vertical pipe (1) is provided with a negative pressure uniform main pipe (12) and a positive pressure uniform main pipe (14). The negative pressure uniform main pipe (12) is connected in parallel with a plurality of negative pressure uniform branch pipes (11). The positive pressure uniform main pipe (14) is connected in parallel with a plurality of positive pressure uniform branch pipes (13). The negative pressure uniform branch pipes (11) are respectively connected in parallel with a plurality of negative pressure outlet pipes (2) on the differential pressure generating tubes (4). The positive pressure uniform branch pipes (13) are respectively connected in parallel with a plurality of positive pressure outlet pipes (6) on the differential pressure generating tubes (4).

6. A vertical duct anti-dust accumulation air volume measuring device as claimed in claim 5, characterized in that: The angle between the negative pressure equalizing branch pipe (11) and the horizontal plane is between 40 degrees and 80 degrees, and the angle between the positive pressure equalizing branch pipe (13) and the horizontal plane is between 40 degrees and 80 degrees.

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