Plug-in type split electromagnetic flowmeter

Abstract

The plug-in type split electromagnetic flowmeter comprises a flowmeter body which is arranged on a to-be-measured pipeline in a plug-in mode, and an electrode of the flowmeter body extends into the to-be-measured pipeline; an ascending pipe, a descending pipe and a flow equalizing mechanism are sequentially arranged at the upstream of the electrode, the ascending pipe is communicated with the descending pipe, the ascending pipe and the descending pipe form an inverted V-shaped structure, and flowing liquid is uniformly distributed in a pipeline space to be detected by the flow equalizing mechanism; a ventilation mechanism is arranged at the joint of the ascending pipe and the descending pipe, the ventilation mechanism is arranged on the outer side wall of the to-be-detected pipeline, the ventilation mechanism is provided with a liquid inlet, and the ventilation mechanism is communicated with the ascending pipe and the descending pipe through the liquid inlet; a ventilation layer is arranged in the ventilation mechanism, only gas can permeate through the ventilation layer, liquid cannot permeate through the ventilation layer, an exhaust mechanism is arranged above the ventilation mechanism, redundant gas and bubbles in the pipeline to be measured can be removed through the ventilation mechanism and the exhaust mechanism, and the influence of the gas in the pipeline to be measured on the measurement result is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of flowmeters, and in particular relates to an insertion-type split electromagnetic flowmeter. Background Art

[0002] In an electromagnetic flowmeter, the conductive medium in the measuring tube is equivalent to the conductive metal rod in the Faraday test. The two electromagnetic coils at the upper and lower ends generate a constant magnetic field. When the conductive medium flows through, an induced voltage is generated. The two electrodes inside the pipe measure the generated induced voltage.

[0003] Since the flow is measured by induced voltage when flowing through a conductive medium, in actual measurement, bubbles will occur when the conductive fluid flows through the pipe to be measured, and the fluid does not fill the pipe, and there will be air cavities inside the pipe. The bubbles in the fluid will change the speed of sound in the liquid, and the change in sound speed will affect the measurement accuracy of the electromagnetic flowmeter. Since bubbles cause changes in liquid density, the speed at which sound waves propagate through the liquid will also change. This change in sound speed may cause deviations in the measurement results of the electromagnetic flowmeter; when bubbles are present in the liquid, they may interfere with the measurement signal of the electromagnetic flowmeter. Bubbles may change the conductivity distribution in the liquid, resulting in inaccurate measurement results of the electromagnetic flowmeter and large errors. Summary of the invention

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide an insertable split electromagnetic flowmeter, which at least solves one of the problems raised in the background technology.

[0005] The present invention provides the following technical solutions: An insertion-type split electromagnetic flowmeter comprises a flowmeter body which is plugged and arranged on a pipeline to be measured, and an electrode of the flowmeter body extends to the inside of the pipeline to be measured; An upward pipe, a downward pipe and a flow equalizing mechanism are sequentially arranged upstream of the electrode, the upward pipe and the downward pipe are connected, the upward pipe and the downward pipe form an inverted "V" structure, and the flow equalizing mechanism evenly distributes the flowing liquid in the space of the pipeline to be tested; A ventilation mechanism is provided at the connection between the ascending pipe and the descending pipe, the ventilation mechanism is arranged on the outer side wall of the pipeline to be tested, and the ventilation mechanism is provided with a liquid inlet, and the ventilation mechanism is connected with the ascending pipe and the descending pipe through the liquid inlet; The ventilation mechanism is provided with a breathable layer, which can only allow gas to pass through but not liquid. An exhaust mechanism is provided above the ventilation mechanism. The ventilation mechanism and exhaust mechanism can remove excess gas and bubbles in the pipeline to be tested, thereby reducing the impact of the gas in the pipeline to be tested on the measurement result.

[0006] Preferably, the ascending pipe is located upstream of the descending pipe, and the connecting end of the ascending pipe and the descending pipe is close to the upper side wall of the pipeline to be tested; the liquid in the pipeline to be tested flows from the ascending pipe to the descending pipe.

[0007] Preferably, the flow balancing mechanism is arranged downstream of the downpipe, and the flow balancing mechanism includes a plurality of annular plates, which are arranged in sequence in the length direction of the pipeline to be tested, and a fixing rod is provided between the plurality of annular plates, which connects the plurality of annular plates, and the center of the annular plates is a hollow structure.

[0008] Preferably, the flow balancing mechanism is able to rotate; one end of the flow balancing mechanism is connected to a turntable, the turntable is provided with a support rod, the turntable is provided with a rotating shaft rotatably connected to the support rod, and the other end of the support rod is connected to the inner wall of the pipeline to be tested; the other side of the turntable is eccentrically connected to a rotating connecting rod, and the other end of the rotating connecting rod is rotatably connected to a vertical connecting rod, the vertical connecting rod penetrates the wall of the pipeline to be tested, and is sealingly and slidingly connected to the pipeline to be tested, and the other end of the vertical connecting rod is connected to the exhaust mechanism, and the flow balancing mechanism is driven to rotate by the exhaust mechanism.

[0009] Preferably, the ventilation mechanism includes a first cylinder, a liquid inlet is provided at the lower end of the first cylinder, and the liquid inlet is connected to the ascending pipe and the descending pipe through the liquid inlet; a breathable layer is provided near the upper part of the interior of the first cylinder, a block is provided below the breathable layer, a channel is opened at the center of the block, a push rod is provided in the channel, and the diameter of the channel is larger than the diameter of the push rod; a moving ball is connected to the lower end of the push rod, and a first spring is provided at a position of the push rod near the moving ball, one end of the first spring is connected to the block, and the other end is connected to the moving ball, and the moving ball can be crimped to seal the channel; a vent is provided at the top of the first cylinder, and the first cylinder is connected to the exhaust mechanism through the vent.

[0010] Preferably, the breathable layer is made of polytetrafluoroethylene or polyimide, which allows air to flow freely. The breathable layer has tiny pores that allow air to pass through and prevent moisture from entering. The pore diameter of the breathable layer is 0.1-10 μm.

[0011] Preferably, the exhaust mechanism includes a second cylinder, which is arranged above the first cylinder, and an air vent is provided between the second cylinder and the first cylinder, a partition is provided inside the second cylinder, the partition is provided with a connecting cavity, an air storage cavity is between the partition and the air vent, the air vent is provided with a movable plate, and the movable plate is rotatably connected to the inner wall of the air storage cavity through a hinge; a piston block is provided on the other side of the partition, a pressure cavity is formed between the piston block and the partition, a blocking block is provided on the other side of the piston block, a balance cavity is between the piston and the blocking block, and the balance cavity is provided with an air hole connected to the outside world.

[0012] Preferably, a middle hole is provided in the center of the blocking block; a movable column is connected to the side of the piston block close to the blocking block, and the other end of the movable column is arranged in the middle hole, the movable column is sealingly and slidingly connected to the middle hole, and the end of the movable column away from the piston block is connected to a connecting rod, and the connecting rod is connected to a vertical connecting rod; an "L"-shaped air channel is provided inside the movable column, one end of the air channel is connected to the pressure chamber, and the other end of the air channel is arranged in the middle hole, and is intermittently blocked by the blocking block when the movable column moves up and down, so that the pressure chamber is intermittently exhausted, and a second spring is provided on the movable column, one end of the second spring is connected to the blocking block, and the other end is connected to the piston block.

[0013] Preferably, an upper air hole is provided on the side of the connecting cavity of the partition close to the pressure cavity, and a lower air hole is provided on the side close to the air storage cavity. A pressure block is provided in the air cavity, which can press the lower air hole. A third spring is connected to the side of the pressure block close to the upper air hole. The third spring and the pressure block arranged in the connecting cavity can complete one-way ventilation from the air storage cavity to the balance cavity.

[0014] Preferably, a box body is provided outside the ventilation mechanism and the exhaust mechanism, and the box body is connected to the outside of the pipeline to be tested.

[0015] In addition, when the flow meter is measuring, after the fluid enters the pipe to be measured, it first enters the ascending pipe. Since the ascending pipe is inclined upward, when the fluid flows from low to high, the upward speed of the bubbles in the fluid will be accelerated, causing the bubbles in the fluid to float upward quickly. When the bubbles reach the end of the ascending pipe and the connection position with the descending pipe, the bubbles are acted upon by the pressure of the flowing water and enter the ventilation mechanism. The air permeable layer in the ventilation mechanism allows the gas to pass through and enter the exhaust mechanism. The moisture cannot pass through the air permeable layer and continue to flow into the descending pipe. Moreover, due to the inverted "V"-shaped setting, when the fluid flows into the descending pipe, the water pressure gradually increases. The bubbles in the water will not continue to enter the descending pipe with the fluid due to the buoyancy, thereby discharging the bubbles in the water flow, achieving a good bubble removal effect and reducing the influence of bubbles on the measurement results. After the fluid flows out of the descending pipe, it passes through the flow balancing mechanism. The flow balancing mechanism sequentially sets four annular plates in the pipe to be measured. The outer diameter of the cut annular plate is smaller than the inner diameter of the pipe to be measured, and the annular plate has a hollow structure. When fluid passes through the flow balancing mechanism, the annular plate closest to the downpipe will block part of the fluid, and at the same time, part of the fluid will continue to flow downstream through the gap formed by the hollow part and edge of the annular plate and the inner wall of the pipe to be tested. Part of the fluid blocked by the annular plate will form a backflow, and the backflowing fluid will merge with the newly entered fluid. Since the flow directions of the backflowing fluid and the newly entered fluid are different, and there will be a certain degree of diffusion, a water vortex will be formed. The water vortex will form a vortex between the annular plate and the inner wall of the pipe to be tested, thereby completely filling the entire cavity of the pipe to be tested. Similarly, when the fluid passes between the two annular plates, a vortex will be formed between the two annular plates, and the pipe to be tested between each part will be completely filled. Therefore, after passing through the flow balancing mechanism, the conductive fluid is not only evenly distributed in the pipe to be tested, but also completely fills the pipe to be tested, preventing the measurement error caused by the cavity at the top of the pipe to be tested when detecting the flow rate, and the liquid fluid of the wire cannot fill the pipe, thereby reducing the error and improving the measurement accuracy. In addition, the flow balancing mechanism has an exhaust mechanism that drives the connecting rod to move up and down, so that the vertical connecting rod drives the rotating connecting rod and the turntable to rotate, and the turntable drives the flow balancing mechanism to rotate. When the flow balancing mechanism rotates, when the conductive liquid fluid is blocked by the annular plate, an eddy current is formed. At the same time, the blocked part of the fluid will be affected by the centrifugal force and move along the radial direction of the annular plate toward the inner wall of the pipeline to be tested. The fluid will fill the space between the annular plate and the inner wall of the pipeline to be tested, thereby preventing a cavity from being formed at the top of the pipeline to be tested.

[0016] In addition, the process of gas in the liquid fluid passing through the ventilation mechanism is that the liquid fluid in the ascending tube enters into the first cylinder through the liquid inlet along with the bubbles. When the liquid pressure is low, the moving ball is acted upon by the elastic force of the first spring. The first spring is a tension spring. The moving ball cannot approach the channel and cannot form a tight pressure connection with the channel. The liquid fluid and the bubbles flow upward through the channel until they pass through the air permeable layer. The molecular diameter of the gas is about 0.0004 μm, while the gap of the air permeable layer is 0.1-10 μm. The diameter of the water molecule is about 400 μm. The gas molecules are subjected to the pressure. The water molecules can quickly pass through the air permeable layer to enter the exhaust mechanism, while the water molecules cannot pass through the air permeable layer, so that the water and gas are separated, and the water molecules continue to flow to the downward tube, and the gas molecules enter the second cylinder through the vent; and when the pressure of the liquid fluid increases, in order to prevent the water pressure from damaging the air permeable layer, the pressure of the flowing liquid increases, and the moving ball presses the first spring upward under the action of the fluid pressure until the moving ball is completely and tightly pressed against the channel, blocking the channel, and the fluid cannot flow upward to the air permeable layer, thereby reducing the pressure of the fluid on the air permeable layer, effectively preventing damage to the air permeable layer, and helping to extend its service life.

[0017] After the gas enters the second cylinder of the exhaust mechanism through the air vent, the movable plate of the air storage chamber of the second cylinder is opened by pressure. When the pressure in the air storage chamber gradually increases, before the pressure block and the lower air hole form a passage, and the air pressure in the air storage chamber is greater than the air pressure above the air permeable layer of the first cylinder, the movable plate is closed; when the pressure in the air storage chamber decreases again, the movable plate is opened by pressure to allow air to enter again; when the pressure in the air storage chamber reaches a certain threshold, the pressure block is compressed by the pressure on the third spring, and the lower air hole is opened. It should be understood that the pressure threshold for opening the pressure block is lower than the pressure threshold for opening the movable plate, so that a certain amount of gas is stored in the air storage chamber; when the pressure block is separated from the lower air hole, the gas in the air storage chamber passes through the lower air hole. The connecting cavity and the upper air hole enter the pressure cavity, and the piston block is pushed to move as the pressure in the pressure cavity increases. When the moving column moves upward and the airway is exposed from the middle hole, the gas in the pressure cavity quickly leaks out from the airway. The diameter of the airway is larger than the diameters of the upper air hole and the lower air hole until the pressure in the pressure cavity is balanced with the external air pressure. The piston block is reset in the opposite direction by the rebound action of the second spring, and the air pressure in the pressure cavity increases slowly again, forming a second piston movement to exhaust gas. This prevents excessive gas storage, increased pressure, and damage to the equipment. While exhausting gas, it drives the connecting rod to move back and forth up and down, thereby driving the vertical connecting rod and indirectly driving the flow equalizing mechanism to rotate. Through the set air storage cavity, a certain amount of gas can be stored. When there are few bubbles in the liquid fluid, the remaining gas in the air storage cavity can be used to indirectly drive the flow equalizing mechanism to avoid the formation of air cavities in the pipeline to be measured, thereby further increasing the accuracy of electromagnetic flowmeter detection.

[0018] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides an insertion type split electromagnetic flowmeter. Through the flow balancing mechanism, the conductive fluid is not only evenly distributed in the pipeline to be measured, but also completely fills the pipeline to be measured after passing through the flow balancing mechanism, thereby preventing measurement errors caused by the presence of a cavity at the top of the pipeline to be measured and the inability of the liquid fluid in the conductor to fill the pipeline when detecting the flow, thereby reducing the error and improving the measurement accuracy.

[0019] When the flow balancing mechanism rotates, after the conductive liquid is blocked by the annular plate, a vortex is formed. At the same time, the blocked part of the fluid will be moved along the radial direction of the annular plate toward the inner wall of the pipeline to be tested due to the centrifugal effect. The fluid will fill the space between the annular plate and the inner wall of the pipeline to be tested, thereby preventing a cavity from being formed at the top of the pipeline to be tested.

[0020] In order to prevent the water pressure from damaging the breathable layer, the pressure of the flowing liquid increases, and the moving ball presses the first spring upward under the action of the fluid pressure until the moving ball is completely and tightly pressed against the channel, blocking the channel. The fluid cannot flow upward to the breathable layer, thereby reducing the pressure of the fluid on the breathable layer, effectively preventing damage to the breathable layer and helping to extend its service life.

[0021] By setting up the air storage chamber, a certain amount of gas can be stored. When there are few bubbles in the liquid fluid, the remaining gas in the air storage chamber can be used to indirectly drive the flow equalization mechanism to avoid the formation of air cavities in the pipeline to be tested, further increasing the accuracy of electromagnetic flowmeter detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 It is an overall schematic diagram of the present invention.

[0024] Figure 2 It is a schematic diagram of the internal structure of the present invention.

[0025] Figure 3 It is a schematic diagram of the current balancing mechanism of the present invention.

[0026] Figure 4 It is a schematic diagram of the annular plate connection structure of the present invention.

[0027] Figure 5 It is a schematic diagram of the ventilation mechanism of the present invention.

[0028] Figure 6It is a schematic diagram of the exhaust mechanism of the present invention.

[0029] Figure 7 It is a schematic diagram of the partially enlarged structure of A of the present invention. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] Embodiment 1: like Figure 1-4 As shown, an insertion-type split electromagnetic flowmeter comprises a flowmeter body 1 which is plugged and arranged on a pipeline 2 to be measured, and an electrode 3 of the flowmeter body 1 extends to the interior of the pipeline 2 to be measured; an ascending pipe 5, a descending pipe 51 and a flow equalizing mechanism 12 are arranged in sequence upstream of the electrode 3, the ascending pipe 5 and the descending pipe 51 are connected, and the ascending pipe 5 and the descending pipe 51 form an inverted "V"-shaped structure, and the flow equalizing mechanism 12 evenly distributes the flowing liquid in the space of the pipeline 2 to be measured; a ventilation mechanism 6 is arranged at the connection between the ascending pipe 5 and the descending pipe 51, the ventilation mechanism 6 is arranged on the outer wall of the pipeline 2 to be measured, and the ventilation mechanism 6 is provided with a liquid inlet 68, and the ventilation mechanism 6 is connected with the ascending pipe 5 and the descending pipe 51 through the liquid inlet 68; a permeable layer 62 is arranged in the ventilation mechanism 6, and the permeable layer 62 can only allow gas to pass through, but liquid cannot pass through, and an exhaust mechanism 7 is arranged above the ventilation mechanism 6, and the ventilation mechanism 6 and the exhaust mechanism 7 can remove excess gas and bubbles in the pipeline 2 to be measured, thereby reducing the image of the gas in the pipeline 2 to be measured on the measurement result. The ascending pipe 5 is located upstream of the descending pipe 51 , and the connecting end of the ascending pipe 5 and the descending pipe 51 is close to the upper side wall of the pipeline 2 to be tested; the liquid in the pipeline 2 to be tested flows from the ascending pipe 5 to the descending pipe 51 .

[0033] The flow balancing mechanism 12 is arranged downstream of the down pipe 51. The flow balancing mechanism 12 includes a plurality of annular plates 121, which are arranged in sequence along the length direction of the pipeline 2 to be tested. A fixing rod 122 is arranged between the plurality of annular plates 121, and the fixing rod 122 connects the plurality of annular plates 121. The center of the annular plates 121 is a hollow structure. The flow balancing mechanism 12 can rotate; a turntable 10 is connected to one end of the flow balancing mechanism 12, and the turntable 10 is provided with a support rod 11. The turntable 10 is provided with a rotating shaft and is rotatably connected to the support rod 11, and the other end of the support rod 11 is connected to the inner wall of the pipeline 2 to be tested; the other side of the turntable 10 is eccentrically connected to a rotating connecting rod 9, and the other end of the rotating connecting rod 9 is rotatably connected to a vertical connecting rod 8, which penetrates the wall of the pipeline 2 to be tested and is sealed and slidably connected to the pipeline 2 to be tested, and the other end of the vertical connecting rod 8 is connected to an exhaust mechanism 7, and the exhaust mechanism 7 drives the flow balancing mechanism 12 to rotate.

[0034] When the flow meter is measuring, after the fluid enters the pipe 2 to be measured, it first enters the ascending pipe 5. Since the ascending pipe 5 is inclined upward, when the fluid flows from low to high, the upward speed of the bubbles in the fluid will be accelerated, so that the bubbles in the fluid float upward quickly. When the bubbles reach the end of the ascending pipe 5 and the connection position with the descending pipe 51, the bubbles are affected by the pressure of the flowing water and enter the ventilation mechanism 6. The air permeable layer 62 in the ventilation mechanism 6 allows the gas to pass through and enter the exhaust mechanism 7. The water cannot pass through the air permeable layer 62 and continues to flow to the descending pipe 51, and Due to the inverted "V"-shaped arrangement, when the fluid flows into the downward pipe 51, the water pressure gradually increases, and the bubbles in the water will not continue to enter the downward pipe 51 with the fluid due to the buoyancy, thereby discharging the bubbles in the water flow, achieving a good bubble removal effect and reducing the influence of bubbles on the measurement results; after the fluid flows out of the downward pipe 51, it passes through the flow balancing mechanism 12, and the flow balancing mechanism 12 sequentially sets four annular plates 121 in the pipeline 2 to be measured, and the outer diameter of the annular plate 121 is smaller than the inner diameter of the pipeline 2 to be measured, and the annular plate 121 is hollow. When fluid passes through the flow balancing mechanism 12, the annular plate 121 closest to the down pipe 51 will block part of the fluid, and at the same time, part of the fluid will continue to flow downstream through the gap formed by the hollow part and edge of the annular plate 121 and the inner wall of the pipeline 2 to be tested, and part of the fluid blocked by the annular plate 121 will form a backflow, and the backflowing fluid will merge with the newly entered fluid. Since the backflowing fluid and the newly entered fluid have different flow directions and will diffuse to a certain extent, a water vortex will be formed, and the water vortex will form between the annular plate 121 and the inner wall of the pipeline 2 to be tested. A vortex is formed between the two annular plates 121, thereby completely filling the entire cavity of the pipeline 2 to be tested. Similarly, when the fluid passes between the two annular plates 121, a vortex is formed between the two annular plates 121, and the pipeline 2 to be tested between each part is completely filled. Therefore, after the conductive fluid passes through the flow equalizing mechanism 12, it is not only evenly distributed in the pipeline 2 to be tested, but also completely fills the pipeline 2 to be tested, thereby preventing the measurement error caused by the cavity at the top of the pipeline 2 to be tested when detecting the flow rate and the inability of the liquid fluid of the wire to fill the pipeline, thereby reducing the error and improving the measurement accuracy. In addition, the flow balancing mechanism 12 has an exhaust mechanism 7 that drives the connecting rod 714 to move up and down, so that the vertical connecting rod 8 drives the rotating connecting rod 9 and the turntable 10 to rotate, and the turntable 10 drives the flow balancing mechanism 12 to rotate. When the flow balancing mechanism 12 rotates, when the conductive liquid fluid is blocked by the annular plate 121, a vortex is formed. At the same time, the blocked part of the fluid will be affected by the centrifugal force and move in the radial direction of the annular plate 121 toward the inner wall of the pipeline 2 to be tested. The fluid will fill the space between the annular plate 121 and the inner wall of the pipeline 2 to be tested, so as to prevent the formation of a cavity at the top of the pipeline 2 to be tested.

[0035] Embodiment 2: Based on the first embodiment, Figure 5-7As shown, the ventilation mechanism 6 includes a first cylinder 61, and a liquid inlet 68 is provided at the lower end of the first cylinder 61, which is connected to the ascending tube 5 and the descending tube 51 through the liquid inlet 68; a breathable layer 62 is provided near the upper part of the interior of the first cylinder 61, and a block 63 is provided below the breathable layer 62, and a channel 64 is opened at the center of the block 63, and a push rod 66 is provided in the channel 64, and the diameter of the channel 64 is greater than the diameter of the push rod 66; a moving ball 65 is connected to the lower end of the push rod 66, and a first spring 67 is provided at the position of the push rod 66 near the moving ball 65, one end of the first spring 67 is connected to the block 63, and the other end is connected to the moving ball 65, and the moving ball 65 can seal and crimp the channel 64; a vent 69 is provided at the top of the first cylinder 61, and the first cylinder 61 is connected to the exhaust mechanism 7 through the vent 69.

[0036] The breathable layer 62 is made of polytetrafluoroethylene or polyimide, which allows air to flow freely. There are tiny pores 711 on the breathable layer 62, which can pass air and prevent moisture from entering. The pores 711 on the breathable layer 62 have a pore size of 0.1-10 μm.

[0037] The exhaust mechanism 7 includes a second cylinder 71, which is arranged above the first cylinder 61. A vent 69 is provided between the second cylinder 71 and the first cylinder 61 for communication. A partition 72 is provided inside the second cylinder 71. The partition 72 is provided with a connecting cavity 721. An air storage cavity 73 is formed between the partition 72 and the vent 69. The vent 69 is provided with a movable plate 74. The movable plate 74 is rotatably connected to the inner wall of the air storage cavity 73 through a hinge. A piston block 76 is provided on the other side of the partition 72. A pressure cavity 75 is formed between the piston block 76 and the partition 72. A blocking block 712 is provided on the other side of the piston block 76. A balance cavity 79 is formed between the piston and the blocking block 712. The balance cavity 79 is provided with an air hole 711 for communication with the outside. A central hole 713 is provided at the center of the blocking block 712; a movable column 77 is connected to the side of the piston block 76 close to the blocking block 712, and the other end of the movable column 77 is arranged in the central hole 713. The movable column 77 is sealed and slidably connected with the central hole 713, and the end of the movable column 77 away from the piston block 76 is connected to the connecting rod 714, and the connecting rod 714 is connected to the vertical connecting rod 8; an "L"-shaped air channel 78 is provided inside the movable column 77, one end of the air channel 78 is connected to the pressure chamber 75, and the other end of the air channel 78 is arranged in the central hole 713. When the movable column 77 moves up and down, it is intermittently blocked by the blocking block 63, so that the pressure chamber 75 is intermittently exhausted, and a second spring 710 is provided on the movable column 77, one end of the second spring 710 is connected to the blocking block 712, and the other end is connected to the piston block 76. The communicating cavity 721 of the partition 72 is provided with an upper vent hole 722711 on one side close to the pressure cavity 75, and a lower vent hole 723711 on one side close to the air storage cavity 73. A pressing block 725 is provided in the vent cavity, and the pressing block 725 can press the lower vent hole 723711. The pressing block 725 is connected to a third spring 724 on one side close to the upper vent hole 722711. The third spring 724 and the pressing block 725 provided in the communicating cavity 721 can complete the one-way ventilation from the air storage cavity 73 to the balance cavity 79. A box body 4 is provided outside the ventilation mechanism 6 and the exhaust mechanism 7, and the box body 4 is connected to the outside of the pipeline 2 to be tested.

[0038] The process of gas in the liquid fluid passing through the ventilation mechanism 6 is as follows: the liquid fluid in the ascending tube 5 enters the first cylinder 61 through the liquid inlet 68 along with bubbles. When the liquid pressure is low, the moving ball 65 is acted upon by the elastic force of the first spring 67. The first spring 67 is a tension spring. The moving ball 65 cannot approach the channel 64 and cannot form a tight pressure connection with the channel 64. The liquid fluid and bubbles flow upward through the channel 64 until they pass through the air permeable layer 62. The molecular diameter of the gas is about 0.0004 μm, while the gap of the air permeable layer 62 is 0.1-10 μm. The diameter of the water molecule is about 400 μm. The gas molecules can be It quickly passes through the breathable layer 62 and enters the exhaust mechanism 7, while water molecules cannot pass through the breathable layer 62, so that water and gas are separated, and water molecules continue to flow to the downward tube 51, and gas molecules enter the second cylinder 71 through the vent 69; and when the pressure of the liquid fluid increases, in order to prevent the water pressure from damaging the breathable layer 62, the pressure of the flowing liquid increases, and the moving ball 65 is pressed upward by the fluid pressure to press the first spring 67 until the moving ball 65 is completely and tightly pressed against the channel 64, blocking the channel 64, and the fluid cannot flow upward to the breathable layer 62, thereby reducing the pressure of the fluid on the breathable layer 62, effectively preventing damage to the breathable layer 62, and helping to extend its service life.

[0039] After the gas enters the second cylinder 71 of the exhaust mechanism 7 through the vent 69, the movable plate 74 of the gas storage chamber 73 of the second cylinder 71 is opened by pressure. When the pressure in the gas storage chamber 73 gradually increases, before the pressure block 725 and the lower air permeable hole 723711 form a passage, and the air pressure in the gas storage chamber 73 is greater than the air pressure above the air permeable layer 62 of the first cylinder 61, the movable plate 74 is closed; when the pressure in the gas storage chamber 73 decreases again, the movable plate 74 is opened by pressure. Start to let air in again; when the pressure in the air storage chamber 73 reaches a certain threshold, the pressure block 725 is compressed by the pressure on the third spring 724, and the lower air vent 723711 opens. It should be understood that the pressure threshold for opening the pressure block 725 is lower than the pressure threshold for opening the movable plate 74, so that a certain amount of gas is stored in the air storage chamber 73; when the pressure block 725 is separated from the lower air vent 723711, the gas in the air storage chamber 73 passes through the lower air vent 723711. The connecting cavity 721 and the upper air hole 722711 enter the pressure cavity 75. As the pressure in the pressure cavity 75 increases, the piston block 76 is pushed to move. When the movable column 77 moves upward and the air channel 78 is exposed from the middle hole 713, the gas in the pressure cavity 75 is quickly discharged from the air channel 78. The diameter of the air channel 78 is larger than the diameters of the upper air hole 722711 and the lower air hole 723711, until the pressure in the pressure cavity 75 is balanced with the external air pressure, the piston block 76 is reversed and reset by the rebound effect of the second spring 710, and the gas in the pressure cavity 75 is released. The pressure increases slowly again, forming a second piston movement to exhaust gas; preventing excessive gas storage, increased pressure, and damage to the equipment; while exhausting gas, the connecting rod 714 is driven to move up and down, thereby driving the vertical connecting rod 8 and indirectly driving the flow equalizing mechanism 12 to rotate; through the set air storage chamber 73, a certain amount of gas can be stored. When there are few bubbles in the liquid fluid, the remaining gas in the air storage chamber 73 can be used to indirectly drive the flow equalizing mechanism 12, thereby avoiding the formation of air cavities in the pipeline 2 to be tested, and further increasing the accuracy of electromagnetic flowmeter detection.

[0040] Other technical solutions not elaborated in detail in the present invention are all existing technologies in the field and will not be described in detail here.

[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various changes and modifications. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An insertion type split electromagnetic flowmeter, characterized in that: The flow meter comprises a flow meter body (1) which is plugged and arranged on a pipe to be measured (2), and an electrode (3) of the flow meter body (1) extends into the interior of the pipe to be measured (2); An ascending pipe (5), a descending pipe (51) and a flow balancing mechanism (12) are sequentially arranged upstream of the electrode (3); the ascending pipe (5) and the descending pipe (51) are connected to each other, the ascending pipe (5) and the descending pipe (51) form an inverted "V"-shaped structure, and the flow balancing mechanism (12) evenly distributes the flowing liquid in the space of the pipeline (2) to be tested; A ventilation mechanism (6) is provided at the connection between the ascending pipe (5) and the descending pipe (51); the ventilation mechanism (6) is arranged on the outer wall of the pipeline (2) to be tested, and the ventilation mechanism (6) is provided with a liquid inlet (68); the ventilation mechanism (6) is connected with the ascending pipe (5) and the descending pipe (51) through the liquid inlet (68); The ventilation mechanism (6) is provided with a breathable layer (62) therein, the breathable layer (62) only allowing gas to pass through but not liquid to pass through, and an exhaust mechanism (7) is provided above the ventilation mechanism (6). The ventilation mechanism (6) and the exhaust mechanism (7) are capable of removing excess gas and bubbles in the pipeline to be tested (2), thereby reducing the influence of the gas in the pipeline to be tested (2) on the measurement result.

2. The insertion type split electromagnetic flowmeter according to claim 1, characterized in that: The ascending pipe (5) is located upstream of the descending pipe (51), and the connecting end of the ascending pipe (5) and the descending pipe (51) is close to the upper side wall of the pipeline to be tested (2); the liquid in the pipeline to be tested (2) flows from the ascending pipe (5) to the descending pipe (51).

3. The insertion type split electromagnetic flowmeter according to claim 1, characterized in that: The flow balancing mechanism (12) is arranged downstream of the down pipe (51), and comprises a plurality of annular plates (121). The annular plates (121) are arranged in sequence along the length direction of the pipeline (2) to be tested, and fixing rods (122) are provided between the plurality of annular plates (121). The fixing rods (122) connect the plurality of annular plates (121), and the center of the annular plates (121) is a hollow structure.

4. The insertion type split electromagnetic flowmeter according to claim 3, characterized in that: The flow balancing mechanism (12) is rotatable; one end of the flow balancing mechanism (12) is connected to a rotating disk (10); the rotating disk (10) is provided with a support rod (11); the rotating disk (10) is provided with a rotating shaft rotatably connected to the support rod (11); the other end of the support rod (11) is connected to the inner wall of the pipeline (2) to be tested; the other side of the rotating disk (10) is eccentrically rotatably connected to a rotating connecting rod (9); the other end of the rotating connecting rod (9) is rotatably connected to a vertical connecting rod (8); the vertical connecting rod (8) penetrates the wall of the pipeline (2) to be tested and is sealed and slidably connected to the pipeline (2) to be tested; the other end of the vertical connecting rod (8) is connected to an exhaust mechanism (7); the exhaust mechanism (7) drives the flow balancing mechanism (12) to rotate.

5. The insertion type split electromagnetic flowmeter according to claim 1, characterized in that: The ventilation mechanism (6) comprises a first cylinder (61), the lower end of which is provided with a liquid inlet (68), which is connected to the upward pipe (5) and the downward pipe (51) through the liquid inlet (68); a gas permeable layer (62) is provided near the upper part of the first cylinder (61), a block (63) is provided below the gas permeable layer (62), a channel (64) is provided at the center of the block (63), a push rod (66) is provided in the channel (64), and the diameter of the channel (64) is large. The diameter of the push rod (66) is greater than that of the push rod (66); a moving ball (65) is connected to the lower end of the push rod (66); a first spring (67) is provided at a position of the push rod (66) close to the moving ball (65); one end of the first spring (67) is connected to the stopper (63) and the other end is connected to the moving ball (65); the moving ball (65) can be sealed and crimped to the channel (64); a vent (69) is provided at the top of the first cylinder (61); the first cylinder (61) is connected to the exhaust mechanism (7) via the vent (69).

6. The insertion type split electromagnetic flowmeter according to claim 5, characterized in that: The air permeable layer (62) is made of polytetrafluoroethylene or polyimide and can allow air to flow freely. The air permeable layer (62) is provided with tiny pores (711) which can pass air and prevent moisture from entering. The pores (711) on the air permeable layer (62) have a pore size of 0.1-10 μm.

7. The insertion type split electromagnetic flowmeter according to claim 1, characterized in that: The exhaust mechanism (7) comprises a second cylinder (71), which is arranged above the first cylinder (61); a vent (69) is provided between the second cylinder (71) and the first cylinder (61) for communication; a partition (72) is provided inside the second cylinder (71); the partition (72) is provided with a communicating cavity (721); an air storage cavity (73) is provided between the partition (72) and the vent (69); the vent (69) is provided with a movable plate (74); the movable plate (74) is rotatably connected to the inner wall of the air storage cavity (73) via a hinge; a piston block (76) is provided on the other side of the partition (72); a pressure cavity (75) is formed between the piston block (76) and the partition (72); a blocking block (712) is provided on the other side of the piston block (76); a balancing cavity (79) is provided between the piston and the blocking block (712); the balancing cavity (79) is provided with an air hole (711) for communication with the outside.

8. The insertion type split electromagnetic flowmeter according to claim 7, characterized in that: The blocking block (712) has a central hole (713) at its center; a movable column (77) is connected to one side of the piston block (76) close to the blocking block (712); the other end of the movable column (77) is disposed in the central hole (713); the movable column (77) is sealingly and slidably connected to the central hole (713); the end of the movable column (77) away from the piston block (76) is connected to a connecting rod (714); the connecting rod (714) is connected to the vertical connecting rod (8); the movable column ( An "L"-shaped air passage (78) is provided inside the movable column (77), one end of the air passage (78) is communicated with the pressure chamber (75), and the other end of the air passage (78) is arranged in the middle hole (713) and is intermittently blocked by the blocking block (63) when the movable column (77) moves up and down, so that the pressure chamber (75) is intermittently exhausted. A second spring (710) is provided on the movable column (77), one end of the second spring (710) is connected to the blocking block (712), and the other end is connected to the piston block (76).

9. The insertion type split electromagnetic flowmeter according to claim 8, characterized in that: An upper air vent (722) (711) is provided on a side of the connecting cavity (721) of the partition (72) close to the pressure cavity (75), and a lower air vent (723) (711) is provided on a side close to the air storage cavity (73). A pressing block (725) is provided in the air vent, and the pressing block (725) is capable of pressing the lower air vent (723) (711). A third spring (724) is connected to a side of the pressing block (725) close to the upper air vent (722) (711). The third spring (724) and the pressing block (725) provided in the connecting cavity (721) are capable of achieving one-way ventilation from the air storage cavity (73) to the balancing cavity (79).

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