Double-flange liquid level difference flowmeter

Abstract

The utility model discloses a double-flange liquid level difference flow meter which comprises a flow meter body, a pipeline is connected to the bottom of the flow meter body, a flow changing piece is arranged in the pipeline, a channel is arranged in the flow changing piece, the diameter of the end, close to the upstream, of the channel is large, and the diameter of the end, close to the downstream, of the channel is small. An anti-backflow mechanism is arranged at one end, close to the downstream, of the variable flow part to prevent liquid in the pipeline from flowing back; hollow pipes are arranged on the upstream and the downstream of the variable flow part, the hollow pipes are communicated with the pipeline, pressed flanges are arranged at the bottoms of the hollow pipes, and the pressed flanges are connected with the interiors of the hollow pipes.

Description

Technical Field

[0001] The utility model belongs to the technical field of flowmeters, and in particular relates to a double-flange liquid level differential flowmeter. Background Art

[0002] The double flange liquid level differential flowmeter is installed with a silicone oil tube between two pressure-taking flanges. The silicone oil tube is connected to the differential pressure transmitter to obtain the pressure difference information. The differential pressure signal is measured by the differential pressure transmitter. The differential pressure is proportional to the square root of the flow rate, thereby measuring the medium flow rate.

[0003] However, the traditional liquid level differential flowmeter is generally used to measure the liquid level or flow at a vertical height. It has certain disadvantages for pipelines arranged in a plane. When used on a horizontal plane, the measurement accuracy is affected to a certain extent because there is no liquid level difference. Utility Model Content

[0004] In view of the shortcomings of the prior art, the purpose of the utility model is to provide a double-flange liquid level differential flowmeter, which at least solves one of the problems of the background technology.

[0005] The utility model provides the following technical solutions:

[0006] A double-flange liquid level differential flowmeter comprises a flowmeter body, a pipeline is connected to the bottom of the flowmeter body, a flow changer is arranged inside the pipeline, a channel is arranged inside the flow changer, the diameter of the channel near the upstream end is large, and the diameter of the channel near the downstream end is small;

[0007] The end of the flow-changing element close to the downstream is provided with a backflow prevention mechanism to prevent the liquid in the pipeline from flowing back;

[0008] A hollow tube is provided upstream and downstream of the flow-changing element. The hollow tube is communicated with the pipeline. A pressure flange is provided at the bottom of the hollow tube. The pressure flange is connected with the inside of the hollow tube.

[0009] Preferably, the channel cross-section inside the variable element is a trapezoidal structure, and the inner side wall of one end of the variable element channel with a small diameter is connected to a support rod, and a limit block is connected to the support rod, and a guide rod is connected to one side of the limit block, and a slidable movable plate is provided on the guide rod; a through hole is provided at the center of the movable plate, and the guide rod is arranged in the through hole, and the movable plate slides on the guide rod through the through hole; a first spring is provided on the guide rod, and one end of the first spring is connected to the movable plate, and the other end is connected to the limit block.

[0010] Preferably, a backflow prevention mechanism is provided on the other side of the limit block, the backflow prevention mechanism comprises a box body, the box body is sealedly connected to the converter, the box body is provided with a guide hole, and the guide hole is provided with a baffle.

[0011] Preferably, the baffle is connected to a second spring, and the other end of the second spring is connected to the limit block; the diameter of the baffle is larger than the diameter of the guide hole, and the baffle is arranged on the outside of the box body.

[0012] Preferably, a sealing box is provided on the top of the hollow tube, an air inlet is provided on one side of the sealing box, and an air outlet is provided on the symmetrical side of the air inlet.

[0013] Preferably, the air inlet is located on the inner side of the sealing box and is provided with an air inlet door, which is rotatably connected to the inner wall of the sealing box through a hinge; the air outlet is located on the outer side of the sealing box and is provided with an air outlet door, which is rotatably connected to the outer wall of the sealing box through a hinge.

[0014] Preferably, a sealing diaphragm is provided inside the pressure flange, and the pressure flange is connected to a silicone oil pipe, which is connected to the differential pressure transmitter through the silicone oil pipe.

[0015] Preferably, when measuring a horizontal pipeline, a flow meter body has a flow changer inside the pipeline, and the inside of the flow changer is a conical structure, the upstream end of the flow changer has a large diameter, and the downstream end has a small diameter; when the fluid passes through the channel of the flow changer, the moving plate inside the flow changer is subjected to the pressure of the fluid, slides on the guide rod toward one end of the limit block, the first spring is compressed, and the flow changer channel is blocked by the moving plate, the channel becomes narrower, the fluid is accelerated, and the kinetic energy of the fluid increases. According to the law of conservation of energy, at the narrow passage where the fluid is accelerated, its static pressure will be reduced to a corresponding low pressure value. It should be understood that the pressure of the fluid after passing through the flow changer is less than the pressure of the upstream fluid, resulting in a pressure difference; when the pressure upstream of the pipeline is greater than the pressure downstream of the pipeline, the heights of the liquid in the hollow tube are different, and the pressures on the two pressure flanges are different. The pressure on the upstream pressure flange is greater than that on the downstream pressure flange. The pressure difference information is obtained by connecting the differential pressure transmitter through a silicone oil tube, and the differential pressure signal is measured by the differential pressure transmitter. The differential pressure is proportional to the square root of the flow rate, thereby measuring the medium flow rate.

[0016] When the device is installed, the hollow tube is installed vertically. In order to prevent the pressure of the air in the hollow tube from affecting the accuracy of measurement, an air inlet hole and an air outlet hole are arranged on the sealing box. When the liquid level in the hollow tube increases, the air inlet valve is closed under pressure, and the air outlet valve is opened under pressure to exhaust; when the liquid level in the hollow tube decreases, the air outlet valve is closed under pressure, and the air inlet valve is opened under negative pressure to complete the air intake. The above process ensures the air pressure balance in the hollow tube, prevents the air in the hollow tube from causing pressure, and further increases the accuracy of measurement.

[0017] Compared with the prior art, the utility model has the following beneficial effects:

[0018] The utility model discloses a double-flange liquid level differential flowmeter, which is provided with an air inlet hole and an air outlet hole on a sealing box. When the liquid level in a hollow tube increases, the air inlet valve is closed under pressure, and the air outlet valve is opened under pressure to exhaust air; when the liquid level in the hollow tube decreases, the air outlet valve is closed under pressure, and the air inlet valve is opened under negative pressure to complete the air intake. The above process ensures the air pressure balance in the hollow tube, prevents the air in the hollow tube from causing pressure, and further increases the accuracy of measurement.

[0019] By setting up an anti-backflow mechanism, when the positive fluid pressure is high, the second spring is stretched, the baffle opens, and the fluid passes forward; when the downstream fluid pressure in the pipeline is high, the baffle is closed by the spring tension, and the fluid cannot flow in the reverse direction, preventing the fluid backflow from affecting the measurement data. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solution of the implementation mode of the utility model, the drawings required for use in the implementation mode will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0022] Figure 2 It is a schematic diagram of the internal structure of the current converter of the utility model.

[0023] Figure 3 It is a schematic diagram of the enlarged structure of the A part of the utility model. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the implementation mode of the utility model clearer, the technical solution in the implementation mode of the utility model will be clearly and completely described below in conjunction with the drawings in the implementation mode of the utility model. Obviously, the described implementation mode is a part of the implementation mode of the utility model, not all the implementation modes. Based on the implementation mode in the utility model, all other implementation modes obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0025] 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 claimed invention, 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 the field without creative work are within the scope of protection of the present invention.

[0026] Embodiment 1:

[0027] like Figure 1-3 As shown, a double flange liquid level differential flowmeter includes a flowmeter body 1, a pipeline 2 is connected to the bottom of the flowmeter body 1, a flow changer 3 is arranged inside the pipeline 2, a channel is arranged inside the flow changer 3, the diameter of the channel is large near the upstream end, and the diameter is small near the downstream end; the end of the flow changer 3 near the downstream end is provided with a backflow prevention mechanism to prevent the liquid in the pipeline 2 from flowing back; hollow tubes 5 are arranged upstream and downstream of the flow changer 3, the hollow tube 5 is connected to the pipeline 2, and a pressure flange 4 is arranged at the bottom of the hollow tube 5, and the pressure flange 4 is connected to the inside of the hollow tube 5. A sealing diaphragm is arranged inside the pressure flange 4, and the pressure flange 4 is connected to a silicone oil pipe 15, and a differential pressure transmitter is connected through the silicone oil pipe 15.

[0028] The channel cross section inside the flow changer 3 is a trapezoidal structure. A support rod 10 is connected to the inner side wall of one end of the small-diameter channel of the flow changer 3. A limit block 9 is connected to the support rod 10. A guide rod 7 is connected to one side of the limit block 9. A sliding movable plate 6 is provided on the guide rod 7. A through hole is provided at the center of the movable plate 6. The guide rod 7 is arranged in the through hole. The movable plate 6 slides on the guide rod 7 through the through hole. A first spring 8 is provided on the guide rod 7. One end of the first spring 8 is connected to the movable plate 6 and the other end is connected to the limit block 9. A backflow prevention mechanism is provided on the other side of the limit block 9. The backflow prevention mechanism includes a box body 11. The box body 11 is sealed and connected to the flow changer 3. A flow guide hole 12 is opened in the box body 11. The flow guide hole 12 is provided with a baffle 14. The baffle 14 is connected to a second spring 13. The other end of the second spring 13 is connected to the limit block 9. The diameter of the baffle 14 is larger than the diameter of the flow guide hole 12. The baffle 14 is arranged on the outside of the box body 11. A sealing box 51 is provided at the top of the hollow tube 5, an air inlet 52 is provided on one side of the sealing box 51, and an air outlet 54 is provided on the symmetrical side of the air inlet 52. The air inlet 52 is located on the inner side of the sealing box 51 and is provided with an air inlet door 53, which is rotatably connected to the inner wall of the sealing box 51 through a hinge; the air outlet 54 is located on the outer side of the sealing box 51 and is provided with an air outlet door 55, which is rotatably connected to the outer wall of the sealing box 51 through a hinge.

[0029] When measuring a horizontal pipeline, a flow changer 3 is provided inside the pipeline 2 of the flow meter body 1. The interior of the flow changer 3 is a conical structure, with a large diameter at the upstream end and a small diameter at the downstream end. When the fluid passes through the channel of the flow changer 3, the moving plate 6 inside the flow changer 3 is subjected to the pressure of the fluid and slides toward one end of the limit block 9 on the guide rod 7. The first spring 8 is compressed, and the channel of the flow changer 3 is blocked by the moving plate 6, so the channel becomes narrower, the fluid is accelerated, and the kinetic energy of the fluid increases. According to the law of conservation of energy, in the narrow passage where the fluid is accelerated, its static pressure It will be reduced to a corresponding low pressure value. It should be understood that the fluid pressure after passing through the flow converter 3 is less than the pressure of the upstream fluid, resulting in a pressure difference. When the pressure upstream of the pipeline 2 is greater than the pressure downstream of the pipeline 2, the heights of the liquids in the hollow tube 5 are different, and the two pressure flanges 4 are subjected to different pressures. The pressure on the upstream pressure flange 4 is greater than that on the downstream pressure flange 4. The pressure differential transmitter is connected through the silicone oil tube 15, and the pressure difference information is obtained. The differential pressure signal is measured by the differential pressure transmitter. The differential pressure is proportional to the square root of the flow rate, thereby measuring the medium flow rate.

[0030] When the device is installed, the hollow tube 5 is installed vertically. In order to prevent the pressure of the air in the hollow tube 5 from affecting the accuracy of the measurement, an air inlet 52 and an air outlet 54 are arranged on the sealing box 51. When the liquid level in the hollow tube 5 increases, the air inlet valve 53 is closed under pressure, and the air outlet valve 55 is opened under pressure to exhaust; when the liquid level in the hollow tube 5 decreases, the air outlet valve 55 is closed under pressure, and the air inlet valve 53 is opened under negative pressure to complete the air intake. The above process ensures the air pressure balance in the hollow tube 5, prevents the air in the hollow tube 5 from causing pressure, and further increases the accuracy of the measurement.

[0031] By setting up an anti-backflow mechanism, when the positive fluid pressure is high, the second spring 13 is stretched, the baffle 14 opens, and the fluid passes in the positive direction; when the fluid pressure downstream in the pipeline 2 is high, the baffle 14 is closed by the spring tension, and the fluid cannot flow in the opposite direction, preventing the fluid backflow from affecting the measurement data.

[0032] 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 modifications and changes. 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. A double flange level differential flowmeter, characterized in that: The flow meter comprises a flow meter body (1), the bottom of the flow meter body (1) is connected to a pipeline (2), a flow changer (3) is provided inside the pipeline (2), a channel is provided inside the flow changer (3), the diameter of the channel near the upstream end is large, and the diameter of the channel near the downstream end is small; The flow-changing element (3) is provided with an anti-backflow mechanism at one end close to the downstream to prevent the liquid in the pipeline (2) from flowing back. A hollow tube (5) is provided upstream and downstream of the flow changer (3); the hollow tube (5) is in communication with the pipeline (2); a pressure flange (4) is provided at the bottom of the hollow tube (5); and the pressure flange (4) is connected to the inside of the hollow tube (5).

2. A double flange level differential flowmeter according to claim 1, characterized in that: The channel cross section inside the flow-changing element (3) is of a trapezoidal structure; the inner side wall of one end of the channel with a small diameter of the flow-changing element (3) is connected to a support rod (10); a limit block (9) is connected to the support rod (10); one side of the limit block (9) is connected to a guide rod (7); a slidable moving plate (6) is provided on the guide rod (7); a through hole is provided at the center of the moving plate (6); the guide rod (7) is arranged in the through hole; the moving plate (6) slides on the guide rod (7) through the through hole; a first spring (8) is provided on the guide rod (7); one end of the first spring (8) is connected to the moving plate (6) and the other end is connected to the limit block (9).

3. A double flange level differential flowmeter according to claim 2, characterized in that: A backflow prevention mechanism is provided on the other side of the limit block (9), the backflow prevention mechanism comprising a box body (11), the box body (11) being sealedly connected to the flow-changing element (3), the box body (11) being provided with a flow guide hole (12), and the flow guide hole (12) being provided with a baffle (14).

4. A double flange liquid level differential flowmeter according to claim 3, characterized in that: The baffle plate (14) is connected to a second spring (13), and the other end of the second spring (13) is connected to the limit block (9); the diameter of the baffle plate (14) is greater than the diameter of the guide hole (12), and the baffle plate (14) is arranged on the outside of the box body (11).

5. A double flange level differential flowmeter according to claim 1, characterized in that: A sealing box (51) is provided at the top of the hollow tube (5), an air inlet (52) is provided on one side of the sealing box (51), and an air outlet (54) is provided on a symmetrical side of the air inlet (52).

6. A double flange level differential flowmeter according to claim 5, characterized in that: The air inlet (52) is located on the inner side of the sealing box (51) and is provided with an air inlet door (53), and the air inlet door (53) is rotatably connected to the inner wall of the sealing box (51) via a hinge; the air outlet (54) is located on the outer side of the sealing box (51) and is provided with an air outlet door (55), and the air outlet door (55) is rotatably connected to the outer wall of the sealing box (51) via a hinge.

7. A double flange level differential flowmeter according to claim 1, characterized in that: A sealing diaphragm is provided inside the pressure flange (4), and a silicone oil pipe (15) is connected to the pressure flange (4), and a differential pressure transmitter is connected via the silicone oil pipe (15).

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