CN105403728B - A kind of measuring device and its measurement method of dusty gas flow velocity - Google Patents

Abstract

The invention relates to a measuring device and a measuring method for the flow rate of dust-laden gas, which comprises more than one positive-pressure pressure-taking tube and a negative-pressure pressure-taking tube extending into the measured pipeline and parallel to the gas flow in the measured pipeline. The bottom ends of the pressure taking tube and the negative pressure taking tube are respectively provided with a positive pressure taking port and a negative pressure taking port, and a positive pressure flow guide mechanism is provided at the positive pressure taking port; Negative pressure diversion mechanism; the positive pressure taking tube and the negative pressure taking tube respectively protrude out of the measured pipeline through a vertical outlet tube to connect with a differential pressure gauge, and the positive pressure taking tube and the differential pressure gauge The positive pressure end is connected, and the negative pressure taking tube is connected with the negative pressure end of the differential pressure gauge; the outlet pipe and the measured pipeline are sealed by a sealing cover, and the outer surface of the sealing cover is fixed to the measured pipeline by several fixing buckles of the opening. The invention has the beneficial effects of simple structure, convenient operation, preventing clogging caused by dusty gas during measurement, reducing influence on measurement results and improving measurement accuracy.

Description

A measuring device and measuring method for dusty gas flow velocity

technical field

The invention relates to the field of gas flow velocity measurement, in particular to a measuring device and a measurement method for dust-laden gas flow velocity.

Background technique

The measurement of the flow rate of dusty gas has always had the problem of clogging the measuring device, especially in the case of vertical air flow. At present, there will be some problems in the application of commonly used measuring devices, such as flute tube, Venturi, back tube, etc. may cause blockage , a single Venturi tube or back tube will also affect the use because of the poor representativeness of the measurement position, and the ash discharge function can be set for the wing-shaped measurement device, but this not only increases the complexity of the operation, but may still affect the measurement or cause clogged.

Contents of the invention

The object of the present invention is to provide a measuring device and method for the flow rate of dusty gas to prevent the clogging caused by dusty gas during the measurement process.

The solution adopted by the present invention to solve the technical problem is: a measuring device for the flow rate of dust-laden gas, including more than one positive pressure pressure tube and a negative pressure tube extending into the pipeline under test and parallel to the air flow in the pipeline under test. Pressure pipe, the bottom ends of the positive pressure taking pipe and the negative pressure taking pipe are respectively provided with a positive pressure taking port and a negative pressure taking port, and a positive pressure diversion mechanism is provided at the positive pressure taking port; A negative pressure diversion mechanism is provided at the negative pressure taking port; the positive pressure taking pipe and the negative pressure taking pipe respectively protrude out of the pipe under test through a lead-out pipe perpendicular to it and connect with a differential pressure gauge , the positive pressure taking tube is connected with the positive pressure end of the differential pressure gauge, and the negative pressure taking tube is connected with the negative pressure end of the differential pressure gauge; The cover is sealed, and the outer surface of the sealing cover is fixed to the opening of the pipeline under test through several fixing buckles.

Further, the positive pressure deflector mechanism includes a first fixing frame, a first rear deflector arranged on the first fixing frame and extending downward and outward along the rear side of the bottom end of the positive pressure taking tube, and A plurality of first deflectors arranged at equal intervals along the longitudinal direction on the front side of the first rear deflector, the first deflectors are arc-shaped; The second rear deflector extending downward and outward along the rear side of the bottom end of the negative pressure taking tube on the second fixing frame and several second guides arranged at equal intervals along the longitudinal direction on the front side of the second rear deflector The flow sheet, the second flow guide sheet is planar.

Further, the distances between the front ends of the adjacent first guide vanes and the second guide vanes are respectively equal, and the distance between the rear end of each first guide vane and the first rear guide vane is equal to one-third of the positive pressure. The width of the mouth, the distance from the rear end of each second deflector to the second rear deflector is equal to one-third of the width of the negative pressure taking port.

Further, the first fixing bracket is installed between the first deflector and the first rear deflector and is located at the end of the first rear deflector; the second fixing bracket is installed between the second deflector and the second rear deflector and at the end of the second rear deflector;

Further, the inner surface of the sealing cover is provided with a boss for maintaining the flow velocity at the opening of the pipeline under test, and the inner surface of the boss is filled with thermal insulation material, and the outer surface of the sealing cover is provided with a boss for connecting with the fixed buckle. Fits fixed ribs.

Further, the fixing buckle is U-shaped, and the two sides of the fixing buckle are buckled on both sides of the sealing cover, and a screw is passed through the outward side of the fixing buckle to fix it.

Further, a sealing material is filled between the sealing surface of the sealing cover and the sealing surface of the pipe opening.

The present invention also provides a measuring method for a dust-laden gas flow rate measuring device as described above. One or more positive pressure measuring points and negative pressure measuring points are respectively set, and the positive pressure measuring points are set at the positive pressure and On the pressure tube and connected to the positive pressure end of the differential pressure gauge; the negative pressure measuring point is set on the negative pressure tube and connected to the negative pressure end of the differential pressure gauge; connect the positive pressure tube and the negative pressure tube to the The air flow in the test pipeline is arranged in parallel for a period, and then it is led out of the flow channel through an outlet pipe through the sealing cover, and connected to the differential pressure gauge. The pressure difference between the positive pressure measuring point and the negative pressure measuring point is calculated by the differential pressure gauge, and the measured pipeline is obtained. The gas flow rate inside.

Further, there are seven positive pressure measuring points and one negative pressure measuring point, and the positive pressure measuring points are evenly distributed in a circular shape in the pipeline under test, and the negative pressure measuring point is located in the middle of the pipeline under test.

Compared with the prior art, the present invention has the following beneficial effects: by paralleling the positive-pressure pressure-taking tube and the negative-pressure pressure-taking tube with the flow direction of the dust-laden gas in the measured pipeline from top to bottom, the measured gas flow rate is at the positive pressure end. The pressure difference between the positive pressure generated and the negative pressure generated at the negative pressure end, and the flow rate of the gas is obtained by measuring the pressure difference between the positive pressure and the negative pressure of the gas. By being located in the positive pressure diversion mechanism and the negative pressure diversion mechanism, it can prevent the clogging phenomenon caused by the dusty gas during the measurement process, reduce the influence on the measurement result, and improve the measurement accuracy. In addition, the sealing cover and the opening of the measured flow channel are tightly matched and sealed through the fixing buckle, which increases the airtightness of the measured flow channel and improves the measurement accuracy. The design of the sealing cover is mainly for the convenience of installation, inspection and maintenance. Usually, if the measuring device is installed, the entire measurement section needs to be replaced, that is, the flow path of the entire fluid, and the measurement section needs to be cut open for inspection and maintenance, which makes construction difficult; The method of construction is better and easier to cooperate with the sealing cover.

Description of drawings

Below in conjunction with accompanying drawing, the patent of the present invention is further described.

FIG. 1 is a schematic structural diagram of a measuring device according to an embodiment of the present invention.

Fig. 2 is a schematic structural view of the forward flow guide mechanism of the measuring device according to the embodiment of the present invention.

Fig. 3 is a structural schematic diagram of the negative flow guide mechanism of the measuring device according to the embodiment of the present invention.

Fig. 4 is a structural schematic diagram of 6 positive pressure measuring points and 1 negative pressure measuring point in the embodiment of the present invention.

Fig. 5 is a structural schematic diagram of 16 positive pressure measuring points and 1 negative pressure measuring point in the embodiment of the present invention.

In the figure: 1-positive pressure taking tube; 2-exit tube; 3-sealing cover; 30-boss; 4-differential pressure gauge; ;8-positive pressure taking port; 9-positive pressure guide mechanism; 90-first rear guide vane; 91-first guide vane; 92-first fixed frame; - negative pressure deflector mechanism; 110 - second rear deflector; 111 - second deflector; 112 - second fixing frame; 12 - positive pressure measuring point; 13 - negative pressure measuring point.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figures 1 to 3, the embodiment of the present invention provides a measuring device for the flow rate of dust-laden gas, which includes more than one positive pressure pressure-taking tube 1 extending into the pipeline under test and parallel to the gas flow in the pipeline under test and a Negative pressure taking pipe 6, the bottom ends of the positive pressure taking pipe 1 and the negative pressure taking pipe 6 are respectively provided with a positive pressure taking port 8 and a negative pressure taking port 10, and the positive pressure taking port 8 A positive pressure guide mechanism 9 is provided at the place; a negative pressure guide mechanism 11 is provided at the negative pressure taking port 10; the positive pressure taking pipe 1 and the negative pressure taking pipe 6 are respectively drawn out The pipe 2 extends out of the pipeline 7 to be tested and is connected with a differential pressure gauge 4, the positive pressure taking tube 1 communicates with the positive pressure end of the differential pressure gauge 4, and the negative pressure taking tube 1 communicates with the differential pressure gauge 4. The negative pressure end of the pressure gauge 4 is connected; the outlet pipe 2 and the measured pipeline 7 are sealed by a sealing cover 3, and the outer surface of the sealing cover 3 is fixed to the opening of the measured pipeline 7 by several fixing buckles 5.

As can be seen from the above, the beneficial effects of the present invention are: by paralleling the flow direction of the dust-laden gas in the measured pipeline 7 with the positive pressure taking pipe 1 or the negative pressure taking pipe 6, the measured gas flow rate forms a differential pressure on the measuring device, The flow rate of the gas is obtained by measuring the difference between the positive and negative pressures of the gas. Through the positive pressure flow guide mechanism 9 and the negative pressure flow guide mechanism 11, the clogging phenomenon caused by the dusty gas during the measurement process is prevented, the influence on the measurement result is reduced, and the measurement accuracy is improved. In addition, the sealing cover 3 and the opening of the measured flow channel are tightly matched and sealed by the fixing buckle 5, which increases the airtightness of the measured flow channel and improves the measurement accuracy. In Fig. 1, the positive pressure taking pipes are partially overlapped.

In this embodiment, the positive pressure diversion mechanism 9 includes a first fixing frame 92, which is arranged on the first fixing frame 92 and extends downward and outward along the rear side of the bottom end of the positive pressure taking tube 1. The first rear deflector 90 and several first deflectors 91 arranged at equal intervals in the longitudinal direction on the front side of the first rear deflector 90, the first deflector 91 is arc-shaped; the negative pressure guide The flow mechanism 11 includes a second fixing frame 112, a second rear deflector 110 arranged on the second fixing frame 112 extending downward and outward along the rear side of the bottom end of the negative pressure taking pipe 6, and several The second deflectors 111 are arranged at equal intervals in the longitudinal direction on the front side of the second rear deflector 110 , and the second deflectors 111 are planar.

As shown in Figure 2, the first rear deflector 90 in the positive deflector mechanism gradually widens downwards along the positive pressure inlet 8, and the taper can be about 30° (15° on one side, vertical direction). The degree of curvature of the rear deflector 90 gradually decreases from bottom to top, and the lower end is basically horizontal. As shown in FIG. The width and height are 3-5 times the width of the pressure-taking port, and the upper end is vertical and smoothly connected with the pressure-taking port. The width of the first deflector 91 can generally be about 1.4 times the width of the first rear deflector 90 at the positive pressure taking port 8 or the same height position, and the number of the deflectors can be 5-7 pieces, each phase The horizontal distance adjacent to the front end of the first guide vane 91 should be equal, and the width of the guide vane in the bending direction closest to the positive pressure taking port 8 is about 1.5 times the width of the positive pressure taking port 8 in the corresponding direction. The shape is concave, and the outer side is higher. The horizontal distance between the front end of the first guide vane 91 and the front end of the positive pressure taking port 8 is 1/3-1/2 the width of the positive pressure taking port 8. The first guide vane 91 and the positive pressure taking port 8 The vertical spacing at the front end of the pressure taking port 8 is also 1/3-1/2 the width of the positive pressure taking port 8, and the front end of the first deflector 91 is upturned by 60-90° (the angle with the horizontal plane). The end (inner side) is horizontal or slightly upturned; the rear end (inner side) of each first deflector 91 is about 1/3 of the width of the pressure opening from the rear deflector.

As shown in FIG. 3 , the difference between the negative pressure deflector mechanism 11 and the positive pressure deflector mechanism 9 is that the second deflector 111 is planar and has a different flow direction from the first deflector.

In this embodiment, the distances between the front ends of the adjacent first guide vanes 91 and the second guide vanes 111 are respectively equal, and the distance between the rear ends of the first guide vanes 91 and the first rear guide vane 90 is equal to three minutes. One of the widths of the positive pressure sampling port 8 and the distance between the rear end of each second deflector 111 and the second rear deflector 110 are equal to one-third of the width of the negative pressure sampling port 10 . The front and rear ends of the first guide vane 91 and the second guide vane 111 need to be rounded and polished to avoid dust accumulation. Positive pressure pressure taking pipe 1 and outlet pipe 2 can be circular and can also be square. The pressure taking pipe 1 of the present invention adopts a square pipe, the size is generally 10-30mm, and the size is too small to prevent clogging. Tube 2 can be round or square.

In this embodiment, the first fixing frame 92 is installed between the first air deflector 91 and the first rear air guide 90 and is located at the end of the first rear air guide 90; The second fixing frame 112 is installed between the second deflector 111 and the second rear deflector 110 and is located at the end of the second rear deflector 110 .

In this embodiment, the inner surface of the sealing cover 3 is provided with a boss 30 for maintaining the flow velocity at the opening of the measured pipeline 7, and the inner surface of the boss 30 is filled with thermal insulation material, and the outer surface of the sealing cover 3 There are ribs for cooperating and fixing with the fixing buckle 5 . The purpose of the boss 30 is to reduce the impact of this position on the flow, so as to ensure the measurement effect. At the same time, for the case of high temperature, the boss 30 should be filled with thermal insulation material. The front portion of the boss 30 has a slope, which is convenient for installation. The plane of the boss 30 and the wall of the flow channel are on the same plane, that is, the flow of the gas in the measured pipeline 7 will not be affected by the sealing cover, which is convenient for installation, maintenance and maintenance. One of the convex ribs is designed on the sealing surface of the sealing cover, and two are designed on the sealing surface of the flow channel side to enhance the sealing effect.

In this embodiment, the fixing buckle 5 is U-shaped, and the two sides of the fixing buckle 5 are buckled on both sides of the sealing cover, and a screw passes through the outward side of the fixing buckle 5 to fix it. . By passing the screw through the threaded hole on one side of the fixing buckle 5, and fixing the bottom end of the screw against the sealing cover, there is no need to provide a threaded hole in the sealing cover, so as to ensure the airtightness of the sealing cover.

In this embodiment, a sealing material is filled between the sealing surface of the sealing cover 3 and the sealing surface of the pipe opening. Sealing materials Waterstops, sealing rings, seals, etc.

The present invention also provides a method for measuring a dust-laden gas flow rate measuring device as described above. By setting one or more positive pressure measuring points 12 and negative pressure measuring points 13 respectively, the positive pressure measuring point 12 is set On the positive pressure taking pipe 1 and connected to the positive pressure end of the differential pressure gauge 4; the negative pressure measuring point 13 is set on the negative pressure taking pipe 6 and connected to the negative pressure end of the differential pressure gauge 4; the positive pressure taking pressure The tube 1 and the negative pressure taking tube 6 are parallel to the air flow in the tested pipeline 7, and are sealed at the opening of the tested pipeline 7 through the sealing cover 3, and the positive pressure measuring point 12 and the negative pressure are calculated by the differential pressure gauge 4 The pressure difference at the measuring point 13 is used to obtain the gas flow rate in the pipeline 7 under test.

In this embodiment, there are seven positive pressure measuring points 12 and one negative pressure measuring point 13, and the positive pressure measuring points 12 are evenly spaced in a ring in the pipeline under test, and the negative pressure measuring points 13 are located in the measured pipeline. The middle of the pipeline, as shown in Figure 4. There may also be six positive pressure measuring points 12 and one negative pressure measuring point 13 .

The present invention also provides an installation diagram of 16 positive pressure measuring points 12 and 1 negative pressure measuring point 13, as shown in FIG. point.

In summary, the device and method for measuring the flow rate of a dusty gas provided by the present invention has a simple structure and is easy to operate, prevents the clogging phenomenon caused by the dusty gas during the measurement process, and reduces the impact on the measurement results. Improve measurement accuracy.

The above preferred embodiments provided by the present invention further describe the purpose, technical solutions and advantages of the present invention in detail. It should be understood that the above descriptions are only preferred embodiments of the present invention and are not intended to limit In the present invention, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims (7)

1. a kind of measuring device of dusty gas flow velocity, it is characterised in that：Stretched in tested pipeline including more than one and with The parallel positive pressure pressure pipe of tested pipeline interior air-flow and a negative pressure pressure pipe, the bottom of the positive pressure pressure pipe and negative pressure pressure pipe End offers positive pressure pressure tappings and negative pressure pressure tappings respectively, and a positive pressure deflector is equipped at the positive pressure pressure tappings；It is described negative It presses and is equipped with a negative-pressure guide mechanism at pressure tappings；The positive pressure pressure pipe and negative pressure pressure pipe are respectively through a perpendicular extraction Pipe extend out to outside tested pipeline and is connect with a difference gauge, and the positive pressure pressure pipe is connected with the positive pressure side of the difference gauge, described Negative pressure pressure pipe is connected with the negative pressure end of the difference gauge；The fairlead and tested pipeline are described close through a seal cap sealing The lateral surface of capping is fixed on the opening of tested pipeline through several fixing buckles；The positive pressure deflector includes one first solid Determine frame, be set to the first fixed frame upper edge positive pressure pressure pipe bottom end on rear side of extend downwardly and outwardly first after flow deflector and Several are set to the first flow deflector on front side of flow deflector after first at equal intervals along longitudinal direction, and first flow deflector is in arcuation；Institute Negative-pressure guide mechanism is stated to include one second fixed frame, be set on rear side of the second fixed frame upper edge negative pressure pressure pipe bottom end downwards And flow deflector is set to the second water conservancy diversion after second on front side of flow deflector at equal intervals along longitudinal direction with several after outwardly extending second Piece, second flow deflector is in planar；The measurement method of the device is：One or more positive pressure measuring point is respectively set With negative pressure measuring point, positive pressure measuring point is set on positive pressure pressure pipe and connects the positive pressure side of difference gauge；Negative pressure measuring point is negative to be set to Press on pressure pipe and connect the negative pressure end of difference gauge；By positive pressure pressure pipe and negative pressure pressure pipe cloth parallel with tested pipeline interior air-flow It is drawn out to outside runner by sealing cover through a fairlead after setting one section, and is access to difference gauge, calculating positive pressure by difference gauge surveys The pressure difference of point and negative pressure measuring point obtains the gas flow rate in tested pipeline.

2. a kind of measuring device of dusty gas flow velocity according to claim 1, it is characterised in that：Each adjacent first water conservancy diversion The spacing of piece and the second flow deflector front end difference is equal, and flow deflector is equal to three after the rear end distance first of each first flow deflector The width of/mono- positive pressure pressure tappings, flow deflector is equal to the negative pressure of one third after the rear end distance second of each second flow deflector The width of pressure tappings.

3. a kind of measuring device of dusty gas flow velocity according to claim 1, it is characterised in that：First fixed frame It is installed in after first flow deflector and first between flow deflector and positioned at the end of flow deflector after described first；Described second is solid It is fixed rack-mounted between flow deflector after second flow deflector and second and positioned at the end of flow deflector after described second.

4. a kind of measuring device of dusty gas flow velocity according to claim 1, it is characterised in that：The sealing cover it is interior Side is equipped with the boss for keeping tested pipeline opening flow velocity, is filled out equipped with thermal insulation material in the boss, the sealing cover Lateral surface be equipped with for coordinating fixed fin with the fixing buckle.

5. a kind of measuring device of dusty gas flow velocity according to claim 1, it is characterised in that：The fixing buckle is in U The both sides of shape, the fixing buckle are buckled in the sealing cover both sides, and pass through the side of the fixing buckle outwardly through a screw It is fixed.

6. a kind of measuring device of dusty gas flow velocity according to claim 1, it is characterised in that：The sealing cover it is close It is filled out equipped with sealing material between cover and the sealing surface of pipeline tapping.

7. a kind of measuring device of dusty gas flow velocity according to claim 1, it is characterised in that：The positive pressure measuring point is Seven, negative pressure measuring point is one, and positive pressure measuring point is evenly spaced in a ring in tested pipeline, and negative pressure measuring point is located at quilt In the middle part of test tube road.