Heat supply steam pipeline flow metering device

Abstract

The utility model relates to the technical field of steam valves, in particular to a heat supply steam pipeline flow metering device which comprises a measuring pipe, a uniform-speed pipe flowmeter, a pipe diameter changing unit arranged on the inner side of the measuring pipe, a plurality of square reducing plates and a driving part. The diameter-variable plates are evenly distributed around the axis of the measuring pipe in the circumferential direction, one side edge of each diameter-variable plate is rotationally connected to the inner wall of the measuring pipe, the pipe diameter changing unit is used for driving the diameter-variable plates to rotate, and when the diameter-variable plates rotate to preset positions, the diameter-variable plates abut against the adjacent diameter-variable plates; the variable-diameter baffle is connected to the end of the variable-diameter plate, abuts against the end of the variable-diameter plate and is used for changing the size of a steam circulation channel along with the variable-diameter plate; a probe tube in the uniform-speed tube flowmeter is positioned in the center of the measuring tube; the steam flow meter can measure the steam flow under the conditions of large pipe diameter and low flow speed.

Description

Technical Field

[0001] This utility model relates to the field of steam valve technology, and in particular to a flow metering device for heating steam pipelines. Background Technology

[0002] Both industrial and residential heating steam need to be metered and settled. The peak and valley differences vary greatly with seasonal changes, user demand and future development requirements. During peak steam consumption, the steam velocity in the pipeline is high, but during off-peak steam consumption, the steam velocity in the pipeline is low.

[0003] Commonly used flow meters for steam metering typically fall into two categories: vortex flow meters and differential pressure flow meters. Vortex flow meters cannot measure steam flow in large-diameter pipes exceeding 300 mm, while industrial parks often have pipe diameters of 600 mm. Although differential pressure flow meters can measure flow in large-diameter pipes, during periods of low steam demand, the steam velocity within the pipe is slow. When the velocity falls below a certain value, the differential pressure flow meter cannot obtain sufficient pressure differential, thus failing to measure the steam flow. Therefore, this application proposes a flow metering device for heating steam pipelines. Summary of the Invention

[0004] The purpose of this invention is to provide a flow metering device for heating steam pipelines to solve the problem that current flow meters cannot measure the flow rate in large-diameter, low-velocity steam pipelines.

[0005] To achieve the above objectives, this utility model provides the following technical solution:

[0006] A flow metering device for heating steam pipelines includes a measuring tube and an averaging pitot tube flow meter, the flow metering device further includes:

[0007] The pipe diameter changing unit located inside the measuring tube includes multiple square diameter changing plates and a driving unit. The multiple diameter changing plates are evenly distributed around the axis of the measuring tube in the circumferential direction. One side of each diameter changing plate is rotatably connected to the inner wall of the measuring tube. The pipe diameter changing unit is used to drive the diameter changing plate to rotate. When the diameter changing plate rotates to a preset position, the diameter changing plate abuts against the adjacent diameter changing plate.

[0008] A variable diameter baffle is connected to and abuts against the end of a variable diameter plate, and is used to change the size of the steam flow channel following the change in diameter plate.

[0009] The probe tube in the averaging pitot tube flowmeter is located at the center of the measuring tube.

[0010] Furthermore, the measuring tube includes a middle shell and an end cap, which are fixedly connected. The middle shell includes an inner middle shell and an outer middle shell, which are concentrically arranged, and the outer middle shell is sleeved on the outside of the inner middle shell. The driving part is located between the inner middle shell and the outer middle shell. The variable diameter plate is installed on the inner wall of the inner middle shell. An end seat is fixed inside the measuring tube. A rotating shaft head is provided at the end of the variable diameter plate, and the rotating shaft head is rotatably connected to the end seat.

[0011] Furthermore, the drive unit includes:

[0012] A first connecting rod, one end of which is fixedly connected to the rotating shaft head;

[0013] The second link is hinged to the end of the first link away from the first link;

[0014] A drive ring is formed, and the end of the second link away from the first link is hinged to the drive ring. Multiple second links are hinged to the drive ring, and the drive ring is rotatably connected to the inner shell.

[0015] A drive cylinder, the output end of which is hinged to the drive ring, and the end of the drive cylinder away from the drive ring is hinged to the inner shell.

[0016] Furthermore, the drive rings located at both ends of the inner shell are connected by a third link, and the output end of the drive cylinder is rotatably connected to the third link.

[0017] Furthermore, the variable diameter baffle is a T-shaped plate, the edges of adjacent variable diameter baffles fit together, the variable diameter baffles are evenly distributed around the axis of the measuring tube in the circumferential direction, and limit blocks and driving blocks are respectively provided on both sides of the variable diameter baffle. The driving block is a cylindrical structure, and the variable diameter baffle is located between the driving plate and the end cap.

[0018] The end cap is provided with a plurality of limiting grooves along the tangent direction of the end cap opening. The limiting grooves are waist-shaped grooves. The drive plate is provided with a plurality of arc-shaped drive grooves. One end of the drive groove is close to the inner side wall of the drive plate, and the other end is close to the outer side wall of the drive plate. The plurality of limiting grooves and the plurality of drive grooves are evenly distributed around the axis of the measuring tube. The limiting block is slidably connected to the limiting groove, and the drive block is slidably connected to the drive groove.

[0019] Furthermore, both the end cap and the drive plate have an annular sealing groove on the side that fits against the variable diameter baffle, and a sealing ring is provided in the sealing groove.

[0020] Furthermore, a pressure platform is provided on the side of the variable diameter baffle connected to the adjacent variable diameter baffle, and the pressure platforms on both sides are respectively located on the two sides of the variable diameter baffle, so that the variable diameter baffle can be pressed alternately on the adjacent pressure platforms.

[0021] Furthermore, the averaging pitot tube flowmeter includes:

[0022] The probe tube is rhomboid in shape and has parallel orifice-shaped pressure measuring cavities inside. Both ends of the pressure measuring cavities are blocked, and the pressure measuring cavities have connecting holes.

[0023] Two pressure guiding tubes are provided, each located at one end of the probe tube and connected to a pressure measuring chamber. The pressure guiding tubes pass through the tube wall on the end cap.

[0024] A differential pressure gauge, wherein the two pressure measuring ports of the differential pressure gauge are respectively connected to different pressure guiding tubes.

[0025] Furthermore, a condenser is provided between the pressure-conducting pipe and the differential pressure gauge. The condenser is a cylindrical tube and is connected to the pressure-conducting pipe and the differential pressure gauge through a pipe interface.

[0026] Furthermore, a control valve is also provided on the pressure guiding pipe for closing the pressure guiding pipe.

[0027] In summary, this utility model has the following advantages compared with the prior art:

[0028] The heating steam pipeline flow metering device disclosed in this embodiment of the utility model installs the averaging pitot tube flow meter in a pipeline structure with an adjustable inner diameter. When measuring steam flow during periods of low steam consumption, the inner diameter is reduced to increase the steam velocity, thereby meeting the measurement requirements of the averaging pitot tube flow meter. After the measurement is completed, the inner diameter is restored to its original state, thus enabling the flow measuring device to measure steam flow under conditions of large pipe diameter and low flow velocity. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of the heating steam pipeline flow metering device disclosed in this embodiment of the utility model.

[0030] Figure 2 for Figure 1 The main view.

[0031] Figure 3 for Figure 2 Sectional view of AA.

[0032] Figure 4This is a schematic diagram of the structure of some parts between the inner shell and the outer shell of the heating steam pipeline flow metering device disclosed in this embodiment of the utility model.

[0033] Figure 5 This is a schematic diagram of the pipe diameter changing unit in the heating steam pipeline flow metering device disclosed in this embodiment of the present invention.

[0034] Figure 6 This is a schematic diagram of the structure of the middle end cover of the heating steam pipeline flow metering device disclosed in an embodiment of this utility model.

[0035] Figure 7 This is a schematic diagram of the variable diameter baffle in the heating steam pipeline flow metering device disclosed in this embodiment of the present invention.

[0036] Figure 8 This is a schematic diagram of the structure of the average pitot tube flowmeter in the heating steam pipeline flow metering device disclosed in this utility model embodiment.

[0037] Figure label:

[0038] 100. Measuring tube; 110. Middle shell; 111. Inner middle shell; 112. Outer middle shell; 113. End seat; 120. End cap; 121. First flange; 122. Second flange; 123. Limiting groove; 130. Drive plate; 131. Drive groove;

[0039] 200. Pipe diameter changing unit; 210. Variable diameter plate; 211. Mounting head; 212. Rotating shaft head; 220. Drive unit; 221. First connecting rod; 222. Second connecting rod; 223. Drive ring; 224. Drive cylinder; 225. Third connecting rod;

[0040] 300. Variable diameter baffle; 301. Limit block; 302. Drive block; 303. Pressing table;

[0041] 400, Averaging pitot tube flow meter; 410, Probe tube; 411, Pressure measuring chamber; 412, Connecting hole; 420, Pressure guiding tube; 421, Guide tube section; 422, Connecting bend; 423, Connecting fixed tube; 430, Condensate tank; 440, Differential pressure gauge; 450, Control valve. Detailed Implementation

[0042] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the protection scope of the present utility model.

[0043] like Figures 1 to 3 As shown, one embodiment of this utility model provides a flow metering device for a heating steam pipeline, the flow metering device comprising:

[0044] Measuring tube 100;

[0045] A pipe diameter changing unit 200 is disposed inside the measuring tube 100. The pipe diameter changing unit 200 includes a plurality of square diameter changing plates 210 and a driving part 220. The plurality of diameter changing plates 210 are evenly distributed around the axis of the measuring tube 100 in the circumferential direction. One side of the diameter changing plate 210 is rotatably connected to the inner wall of the measuring tube 100. The pipe diameter changing unit 200 is used to drive the diameter changing plate 210 to rotate. When the side of the diameter changing plate 210 away from the inner wall of the measuring tube 100 rotates to a preset position, it can abut against the adjacent diameter changing plate 210.

[0046] A variable diameter baffle 300 is connected to and abuts against the end of the variable diameter plate 210, and is used to change the size of the steam flow channel following the variable diameter plate 210.

[0047] An averaging pitot tube flow meter 400 includes a probe tube 410, a pressure guiding tube 420, and a differential pressure gauge 440. The probe tube 410 is located at the center of the measuring tube 100. The pressure guiding tube 420 passes through the wall of the measuring tube 100 from a position near the end of the measuring tube 100 and connects the probe tube 410 and the differential pressure gauge 440. The differential pressure gauge 440 is fixedly connected to the outside of the measuring tube 100.

[0048] In this embodiment, the flow metering device disclosed in this application measures flow velocity in two ways. During peak steam consumption, the steam velocity reaches the measurement requirements of the averaging pitot tube flowmeter 400. The variable diameter plate 210 rotates to a position where it does not contact the adjacent variable diameter plate 210. At this time, the cross-section of the measuring tube 100 is the cross-sectional area of ​​the tube minus the cross-sectional area of ​​the variable diameter plate 210 and the cross-sectional area of ​​the pressure guiding tube 420. At this time, the averaging pitot tube flowmeter 400 can measure the steam velocity, thereby measuring the steam flow rate. During off-peak steam consumption, the steam velocity is lower. At this time, the driving unit 220 drives the variable diameter plate 210 to rotate. When the variable diameter plate 210 rotates, the side facing away from the inner wall of the measuring tube 100 abuts against the adjacent variable diameter plate 210. The variable diameter plate 210 forms a steam flow channel, and the diameter of the variable diameter baffle 300 is reduced. Since the ends of the variable diameter baffle 300 and the variable diameter plate 210 abut against each other, steam cannot enter between adjacent variable diameter plates 210. Thus, the variable diameter baffle 300 and the variable diameter plate 210 form a steam flow channel with a diameter smaller than the inner diameter of the measuring tube 100. At this time, the flow channel for steam entering the measuring tube 100 becomes smaller. According to Bernoulli's principle, the steam velocity in the measuring tube 100 increases, so that when steam consumption is low, the steam velocity in the measuring tube 100 reaches the measurement requirements of the averaging pitot tube flowmeter 400. After the measurement is completed, the variable diameter plate 210 and the variable diameter baffle 300 return to their original state, so that the steam continues to flow in its original state, thereby reducing pressure difference loss.

[0049] The heating steam pipeline flow metering device disclosed in this embodiment of the utility model installs the averaging pitot tube flow meter 400 in a pipeline structure with an adjustable inner diameter. When measuring steam flow during periods of low steam consumption, the inner diameter is reduced to increase the steam velocity, thereby meeting the measurement requirements of the averaging pitot tube flow meter 400. After the measurement is completed, the inner diameter is restored to its original state, thus enabling the flow measuring device to measure steam flow under conditions of large pipe diameter and low flow velocity.

[0050] Specifically, such as Figure 3 As shown, in this embodiment, the measuring tube 100 includes a middle shell 110 and an end cap 120. The middle shell 110 and the end cap 120 are connected by bolts, and the end cap 120 is fixedly connected to the port of the middle shell 110.

[0051] In a preferred embodiment of this invention, the middle shell 110 includes an inner shell 111 and an outer shell 112. The inner shell 111 and the outer shell 112 are concentrically arranged, and the outer shell 112 is sleeved on the outside of the inner shell 111. The driving part 220 is located between the inner shell 111 and the outer shell 112. The variable diameter plate 210 is installed on the inner wall of the inner shell 111. The inner shell 111 and the outer shell 112 are connected by screws. That is, the outer side of the inner shell 111 is provided with a mounting post with a threaded hole, and the fastening screw passes through the outer shell 112 and is fixed to the mounting post.

[0052] In this embodiment, as Figure 3 and Figure 5 As shown, the variable diameter plate 210 is mounted to the inner wall of the inner shell 111 via the mounting head 211. The mounting head 211 has a cylindrical structure and is provided with a strip-shaped mounting block. The mounting block is provided with a strip-shaped groove. The pipe diameter changing unit 200 is embedded in the mounting block on the mounting head 211. The pipe diameter changing unit 200 and the mounting head 211 are connected by screws. End seats 113 are also provided at both ends of the inner shell 111. The end seat 113 is a stepped tube, and the end seat 113 is sleeved on the end of the inner shell 111. The end seat 113 and the inner shell 111 are fixedly connected by welding. The mounting head 211 is provided with a rotating shaft head 212 at both ends. The rotating shaft head 212 passes through the end seat 113 and is located on the outside of the end seat 113. The pipe diameter changing unit 200 is parallel to the axis of the measuring tube 100. The driving part 220 is connected to the rotating shaft head 212.

[0053] like Figure 5 As shown, the drive unit 220 includes a first connecting rod 221, a second connecting rod 222, a drive ring 223, and a drive cylinder 224. One end of the first connecting rod 221 is fixedly connected to the rotating shaft head 212. The second connecting rod 222 is hinged to the end of the first connecting rod 221 away from the first connecting rod 221. The end of the second connecting rod 222 away from the first connecting rod 221 is hinged to the drive ring 223. Multiple second connecting rods 222 are all hinged to the drive ring 223, which is rotatably connected. On the inner shell 111, the drive cylinder 224 is a pneumatic cylinder. The drive cylinder 224 is driven by steam pressure. The output end of the drive cylinder 224 is hinged to the drive ring 223. The end of the drive cylinder 224 away from the drive ring 223 is hinged to the inner shell 111. When the drive cylinder 224 extends or retracts, it drives the drive ring 223 to rotate, thereby driving the rotating shaft head 212 to rotate through the second connecting rod 222 and the first connecting rod 221, and then driving the pipe diameter changing unit 200 to rotate.

[0054] Preferably, in this embodiment, the drive rings 223 located at both ends of the inner shell 111 are connected by a third connecting rod 225. The third connecting rod 225 has threaded holes at both ends, and the third connecting rod 225 is threadedly connected to the pin on the drive ring 223. The output end of the drive cylinder 224 is rotatably connected to the third connecting rod 225.

[0055] In this embodiment, a drive plate 130 is rotatably connected to the inner side of the end cap 120, and a drive ring 223 is fixedly connected to the drive plate 130. The end cap 120 limits the drive plate 130 through a stepped structure. The drive plate 130 is annular, and the drive ring 223 is concentrically arranged with the drive plate 130, and the two are an integral structure.

[0056] As a preferred embodiment of this example, Figure 4 , Figure 6 and Figure 7 As shown, the variable diameter baffle 300 is a T-shaped plate, with the edges of adjacent variable diameter baffles 300 fitting together. The variable diameter baffles 300 are evenly distributed around the axis of the measuring tube 100 in the circumferential direction. Limiting blocks 301 and driving blocks 302 are respectively provided on both sides of the variable diameter baffle 300. The limiting blocks 301 are waist-shaped blocks, and the driving blocks 302 are cylindrical structures. The variable diameter baffle 300 is located between the driving plate 130 and the end cap 120. The end cap 120 is provided with a plurality of limiting grooves 123 along the tangent direction of the opening of the end cap 120. The limiting grooves 123 are waist-shaped grooves. The driving plate 130 is provided with a plurality of arc-shaped driving grooves 131, one end of which is close to the driving plate. The inner wall of the measuring tube 100 has one end close to the outer wall of the drive plate 130. The plurality of limiting grooves 123 and the plurality of drive grooves 131 are evenly distributed around the axis of the measuring tube 100. The limiting block 301 is slidably connected to the limiting groove 123, and the drive block 302 is slidably connected to the drive groove 131. When the drive plate 130 rotates, the drive plate 130 drives the variable diameter baffle 300 to slide along the limiting groove 123. When the variable diameter baffle 300 slides to the end of the limiting groove 123 near the edge, the opening formed by the variable diameter baffle 300 becomes larger. When the variable diameter baffle 300 slides to the end near the center, the opening formed by the variable diameter baffle 300 becomes smaller.

[0057] In a preferred embodiment of this invention, both the end cap 120 and the drive plate 130 are provided with an annular sealing groove on the side that fits against the variable diameter baffle 300, and a sealing ring is provided in the sealing groove.

[0058] In a preferred embodiment of this invention, a pressure platform 303 is provided on the side of the variable diameter baffle 300 connected to the adjacent variable diameter baffle 300. The pressure platforms 303 on both sides are located on the two sides of the variable diameter baffle 300, so that the variable diameter baffle 300 can be pressed alternately on the adjacent pressure platforms 303, thereby improving the sealing between the variable diameter baffles 300 and reducing the penetration of steam.

[0059] In this embodiment, the drive unit 220 is located between the inner shell 111 and the outer shell 112. The end cap 120 is cylindrical, and both ends of the end cap 120 are provided with end plate structures. The outer diameter of the end plate at the end of the end cap 120 connected to the measuring tube 100 is larger than that at the other end of the end cap 120. The two ends of the end cap 120 are respectively provided with a first flange 121 and a limiting groove 123. The first flange 121 is used to connect to the steam pipeline, and the second flange 122 is used to connect to the outer shell 112.

[0060] As a preferred embodiment of this example, Figure 3 and Figure 8 As shown, the averaging pitot tube flowmeter 400 includes a probe tube 410, pressure guiding tubes 420, and a differential pressure gauge 440. The probe tube 410 is rhomboid in shape and has parallel perforated pressure measuring chambers 411 inside. Both ends of the pressure measuring chambers 411 are blocked, and each pressure measuring chamber 411 has a connecting hole 412. There are two pressure guiding tubes 420, which are located at the two ends of the probe tube 410 and are connected to one of the pressure measuring chambers 411. The pressure guiding tubes 420 pass through the tube wall on the end cap 120. The two pressure measuring ports of the differential pressure gauge 440 are connected to different pressure guiding tubes 420. When measuring pressure, the connecting holes 412 on both sides of the probe tube 410 are located upstream and downstream of the steam, respectively.

[0061] Specifically, the pressure guiding tube 420 includes a conduit portion 421, a connecting bend 422, and a connecting fixed tube 423. The conduit portion 421 is connected to the probe tube 410. The connecting fixed tube 423 is embedded in the end cap 120 by welding. The two ends of the connecting bend 422 are fixed to the conduit portion 421 and the connecting fixed tube 423 by nuts.

[0062] Preferably, a condenser 430 is further provided between the pressure-conducting pipe 420 and the differential pressure gauge 440. The condenser 430 is a cylindrical tube and is connected to the pressure-conducting pipe 420 and the differential pressure gauge 440 through a pipe interface. The condenser 430 can prevent the generation of bubbles and the superposition of damping.

[0063] The differential pressure gauge 440 is existing technology.

[0064] Preferably, in this embodiment, the pressure guiding pipe 420 is further provided with a control valve 450 for closing the pressure guiding pipe 420.

[0065] The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular forms “a,” “the,” and “the” used in this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0066] It should be understood that although the terms first, second, third, etc., may be used in this invention to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this invention, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0067] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A flow metering device for heating steam pipelines, comprising a measuring tube and an averaging pitot tube flow meter, characterized in that, The flow metering device also includes: The pipe diameter changing unit located inside the measuring tube includes multiple square diameter changing plates and a driving unit. The multiple diameter changing plates are evenly distributed around the axis of the measuring tube in the circumferential direction. One side of each diameter changing plate is rotatably connected to the inner wall of the measuring tube. The pipe diameter changing unit is used to drive the diameter changing plate to rotate. When the diameter changing plate rotates to a preset position, the diameter changing plate abuts against the adjacent diameter changing plate. A variable diameter baffle is connected to and abuts against the end of a variable diameter plate, and is used to change the size of the steam flow channel following the change in diameter plate. The probe tube in the averaging pitot tube flowmeter is located at the center of the measuring tube.

2. The steam pipeline flow metering device according to claim 1, characterized in that, The measuring tube includes a middle shell and an end cap, which are fixedly connected. The middle shell includes an inner shell and an outer shell, which are concentrically arranged, with the outer shell sleeved on the outside of the inner shell. The driving unit is located between the inner shell and the outer shell. The variable diameter plate is installed on the inner wall of the inner shell. An end seat is fixed inside the measuring tube. A rotating shaft head is provided at the end of the variable diameter plate and is rotatably connected to the end seat.

3. The steam pipeline flow metering device according to claim 2, characterized in that, The drive unit includes: A first connecting rod, one end of which is fixedly connected to the rotating shaft head; The second link is hinged to the end of the first link away from the first link; A drive ring is formed, and the end of the second link away from the first link is hinged to the drive ring. Multiple second links are hinged to the drive ring, and the drive ring is rotatably connected to the inner shell. A drive cylinder, the output end of which is hinged to the drive ring, and the end of the drive cylinder away from the drive ring is hinged to the inner shell.

4. The steam pipeline flow metering device according to claim 3, characterized in that, The drive rings located at both ends of the inner shell are connected by a third link, and the output end of the drive cylinder is rotatably connected to the third link.

5. The steam pipeline flow metering device according to any one of claims 2-4, characterized in that, The variable diameter baffle is a T-shaped plate, and the edges of adjacent variable diameter baffles fit together. The variable diameter baffles are evenly distributed around the axis of the measuring tube in the circumferential direction. Limiting blocks and driving blocks are respectively provided on both sides of the variable diameter baffle. The driving block is a cylindrical structure. The variable diameter baffle is located between the driving plate and the end cap. The end cap is provided with a plurality of limiting grooves along the tangent direction of the end cap opening. The limiting grooves are waist-shaped grooves. The drive plate is provided with a plurality of arc-shaped drive grooves. One end of the drive groove is close to the inner side wall of the drive plate, and the other end is close to the outer side wall of the drive plate. The plurality of limiting grooves and the plurality of drive grooves are evenly distributed around the axis of the measuring tube. The limiting block is slidably connected to the limiting groove, and the drive block is slidably connected to the drive groove.

6. The steam pipeline flow metering device according to claim 5, characterized in that, Both the end cap and the drive plate have an annular sealing groove on the side that fits against the variable diameter baffle, and a sealing ring is provided in the sealing groove.

7. The steam pipeline flow metering device according to claim 5, characterized in that, A pressure platform is provided on one side of the variable diameter baffle that is connected to the adjacent variable diameter baffle. The pressure platforms on both sides are located on the two sides of the variable diameter baffle, so that the variable diameter baffle can be pressed alternately on the adjacent pressure platforms.

8. The steam pipeline flow metering device according to any one of claims 2-4, characterized in that, The averaging pitot tube flow meter includes: The probe tube is rhomboid in shape and has parallel orifice-shaped pressure measuring cavities inside. Both ends of the pressure measuring cavities are blocked, and the pressure measuring cavities have connecting holes. Two pressure guiding tubes are provided, each located at one end of the probe tube and connected to a pressure measuring chamber. The pressure guiding tubes pass through the tube wall on the end cap. A differential pressure gauge, wherein the two pressure measuring ports of the differential pressure gauge are respectively connected to different pressure guiding tubes.

9. The steam pipeline flow metering device according to claim 8, characterized in that, A condenser is also provided between the pressure-conducting pipe and the differential pressure gauge. The condenser is a cylindrical tube and is connected to the pressure-conducting pipe and the differential pressure gauge through a pipe interface.

10. The steam pipeline flow metering device according to claim 8, characterized in that, The pressure-conducting pipe is also equipped with a control valve for closing the pressure-conducting pipe.

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