Airtightness and comparison testing device for a gas ultrasonic flowmeter

Abstract

The application discloses a kind of gas ultrasonic flowmeter air tightness and comparison test device, it is related to gas flowmeter technical field, a kind of gas ultrasonic flowmeter air tightness and comparison test device, including comparison circulation unit, the comparison circulation unit is connected with control unit, the control unit includes control box, the control box and comparison circulation unit are communicated with comparison circulation air inlet pipe, the comparison circulation unit includes first pipeline and second pipeline, the first pipeline and second pipeline are communicated, and the comparison circulation air inlet pipe and second pipeline are communicated;The outside of the comparison circulation unit is provided with power unit, the power unit is provided with air inlet and air outlet pipe, the air inlet pipe and air outlet pipe are communicated with first pipeline and second pipeline respectively, and the outside of the comparison circulation unit is further provided with leak detection unit, and the leak detection unit includes workbench, by the above technical scheme, constant pressure stable detection can be realized, and detection precision is higher.

Description

Technical Field

[0001] This invention belongs to the field of gas flow meter technology, specifically a gas ultrasonic flow meter air tightness and comparison testing device. Background Technology

[0002] Before leaving the factory, gas flow meters need to go through many processes, including motherboard debugging, base meter testing, base meter air tightness testing (leak detection), final assembly, final inspection, calibration, comparison, factory inspection, and packaging. Leak detection and comparison are two of the more important processes.

[0003] Leak detection devices and comparison devices often require two types of equipment. The comparison device is a simple device in which the standard meter (flow meter) and the meter being tested (flow meter) are installed on the same pipeline. During the comparison, manual comparison is performed under normal pressure conditions. The comparison time is generally short. Because the comparison is done manually, it is prone to errors and is not efficient.

[0004] Existing flow meter comparison devices typically use a combination of pressure regulating valves and throttling valves to adjust pipeline flow. When the pipeline is pressurized to a fixed pressure, operators need to repeatedly adjust the opening of the throttling valve to match the target flow. Pressure fluctuations will directly cause flow drift, and there is no stable linear correspondence between flow and valve opening. Especially when multiple meters are compared in parallel in batches, uneven pipeline pressure drop can easily lead to large differences in the flow of each meter being measured. The adjustment operation is cumbersome, the comparison repeatability is poor, and it seriously affects the accuracy of flow meter indication error detection. Summary of the Invention

[0005] To address the problems mentioned in the background art, the present invention proposes a gas ultrasonic flow meter air tightness and comparison testing device.

[0006] The objective of this invention can be achieved through the following technical solution: a gas ultrasonic flow meter air tightness and comparison testing device, comprising a comparison circulation unit, wherein the comparison circulation unit is connected to a control unit, the control unit includes a control box, and a comparison circulation inlet pipe is connected between the control box and the comparison circulation unit; the comparison circulation unit includes a first pipe and a second pipe, the first pipe and the second pipe are connected, and the comparison circulation inlet pipe and the second pipe are connected; a power unit is provided outside the comparison circulation unit, the power unit is provided with an inlet and an outlet, the inlet and the outlet are respectively connected to the first pipe and the second pipe; a leak detection unit is also provided outside the comparison circulation unit, the leak detection unit includes a workbench, a flow meter is installed on the workbench, and a leak detection inlet pipe is connected between the control box and the flow meter.

[0007] As a further preferred embodiment of this technical solution: the comparison cycle unit further includes a standard meter and multiple meters to be tested, wherein the standard meter and the meters to be tested are both flow meters, and both the standard meter and the meters to be tested are installed on the second pipeline.

[0008] As a further preferred embodiment of this technical solution: a plurality of lifting frames are connected between the first pipe and the second pipe. Each lifting frame includes a telescopic rod and a valve. The telescopic rod is installed on the first pipe and its telescopic end is fixedly connected to the second pipe. The valve is installed on the telescopic rod.

[0009] As a further preferred embodiment of this technical solution: multiple support frames are installed on the first pipeline, the control unit also includes a vacuum pump, and a connecting pipe connects the vacuum pump and the control box, thereby connecting the vacuum pump and the comparison circulation unit. The control box is also connected to a gas source.

[0010] As a further preferred embodiment of this technical solution: a cable interface is installed on the power tank, a motor cable is connected between the cable interface and the control box, a support rod is fixedly connected to the power tank, and a blind plate is fixedly connected to the power tank.

[0011] As a further preferred embodiment of this technical solution: a fan is installed inside the power tank, and the fan is equipped with an air outlet and an air inlet, which are respectively connected to an air outlet and an air inlet.

[0012] As a further preferred embodiment of this technical solution: the leak detection unit further includes a power box, which is mounted on a workbench, and a top pressure flange is connected to the power box. An adjusting wrench for driving the top pressure flange is also installed on the power box.

[0013] As a further preferred embodiment of this technical solution: a square groove is provided on the workbench, and a set of support plates is slidably connected in the square groove. Two support plates are provided in the set and are slidably connected in the square groove.

[0014] As a further preferred embodiment of this technical solution: the flow meter is installed between two support plates, and the top pressure flange is fitted with the flow meter.

[0015] As a further preferred embodiment of this technical solution: a slide rail is fixedly connected inside the square groove, the support plate is slidably connected to the slide rail, a positioning frame is fixedly connected to the worktable, and a rubber pad is fixedly connected to the positioning frame.

[0016] Compared with the prior art, the beneficial effects of the present invention are:

[0017] 1. In this invention, the control unit can simultaneously perform accuracy comparison testing on multiple flow meters under test. The control unit has a built-in PLC, proportional valve, and solenoid valve, which can accurately and stably control the gas pressure and flow rate in the comparison circulation pipeline. There is no need for operators to frequently manually adjust the valve opening to match the target flow rate. This not only improves the adjustment efficiency of the comparison test, but also improves the flow control accuracy. Under the premise of constant pressure, the flow rate is linearly controlled by only the single variable of the fan frequency, forming a constant pressure variable frequency flow control closed-loop control logic, thereby improving the detection accuracy of the flow meter indication error. At the same time, the device can simultaneously accommodate multiple flow meters under test for synchronous testing, resulting in higher testing efficiency, more sufficient sample data, and further improving the reliability of the test results.

[0018] 2. In this invention, the comparison cycle unit and the leak detection unit are connected by a control unit, thereby realizing the two detection processes of leak detection and comparison at the same time. The leak detection and comparison functions are controlled by a unified control unit. It can be used for leak detection and live comparison of various gas flow meters such as gas ultrasonic flow meters, gas rotary flow meters, and gas turbine flow meters. During comparison, live comparison at different pressure points can be realized.

[0019] 3. In this invention, the control box can control the gas source to provide positive pressure to the comparison cycle running platform and the leak test platform, or it can provide negative pressure to the comparison cycle unit and the leak test unit, so as to meet the requirements of gas ultrasonic flow meter air tightness detection and accuracy comparison under different pressure conditions and expand the applicable scenarios of the device. Attached Figure Description

[0020] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0021] Figure 2 This is a schematic diagram of the control unit of the present invention;

[0022] Figure 3 For the present invention Figure 1 Enlarged structural diagram at point A;

[0023] Figure 4 This is a schematic diagram of the power unit structure of the present invention;

[0024] Figure 5 This is a schematic diagram of the internal structure of the power tank of the present invention;

[0025] Figure 6 This is a schematic diagram of the leak detection unit structure of the present invention;

[0026] Figure 7 This is a cross-sectional structural diagram of the leak detection unit of the present invention.

[0027] Legend: 1. Comparison cycle unit; 102. First pipeline; 103. Second pipeline; 104. Standard gauge; 105. Gauge under test; 106. Support frame; 107. Lifting frame; 1071. Telescopic rod; 1072. Valve; 2. Leak detection unit; 201. Power box; 202. Pressure gauge; 203. Adjusting wrench; 204. Top pressure flange; 205. Flow meter; 206. Workbench; 207. Support 208. Support plate; 209. Positioning frame; 210. Slide rail; 3. Rubber pad; 3. Control unit; 301. Control box; 302. Vacuum pump; 303. Air source; 304. Comparison and circulation air inlet pipe; 305. Motor cable; 306. Leak test air inlet pipe; 4. Power unit; 41. Power tank; 42. Air inlet; 43. Air outlet; 44. Support rod; 45. Blind plate; 46. Cable interface; 47. Fan. Detailed Implementation

[0028] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1:

[0030] Please see Figures 1-7 This application provides a gas ultrasonic flow meter air tightness and comparison testing device, including a comparison circulation unit 1. The comparison circulation unit 1 is connected to a control unit 3. The control unit 3 includes a control box 301. A comparison circulation inlet pipe 304 connects the control box 301 and the comparison circulation unit 1. The comparison circulation unit 1 includes a first pipe 102 and a second pipe 103, which are connected. The comparison circulation inlet pipe 304 is also connected to the second pipe 103. A proportional valve, multiple solenoid valves, and a PLC are installed in the control box 301. The PLC controls the proportional valve and solenoid valves to adjust the comparison circulation. The intake speed and volume of the air intake pipe 304 are adjusted to maintain stable pipeline pressure in the comparison circulation unit 1. The comparison circulation unit 1 also includes a standard meter 104 and multiple measured meters 105. Both the standard meter 104 and the measured meters 105 are flow meters. Both the standard meter 104 and the measured meters 105 are installed on the second pipeline 103. Real-time data such as total volume, instantaneous flow rate, temperature, and pressure of the standard meter 104 (flow meter) and the measured meters 105 (flow meter) are collected during operation for comparison between the standard meter 104 (flow meter) and the measured meters 105 (flow meter). A display screen is installed on the control box 301, and the real-time data is displayed on the display screen.

[0031] The control unit 3 ensures constant pressure in the first pipe 102 and the second pipe 103 of the comparison cycle unit 1. The PLC controls the proportional valve and the solenoid valve to precisely control the air intake speed and volume of the comparison cycle air intake pipe 304, thus eliminating the need to frequently adjust the opening of the proportional valve and the solenoid valve to match the target flow rate. This not only improves the adjustment efficiency but also the adjustment accuracy, thereby improving the accuracy of flow meter indication error detection. In addition, the multiple standard meters 104 and the meter under test 105 can provide multiple comparison data and multiple samples, thereby improving the detection accuracy.

[0032] Please see Figures 1-3 The comparison circulation unit 1 is externally equipped with a power unit 4. The power unit 4 is equipped with an air inlet 42 and an air outlet 43. The air inlet 42 and the air outlet 43 are respectively connected to the first pipe 102 and the second pipe 103. The power unit 4 is used to supply air to the comparison circulation unit 1 for the airtightness detection of the standard meter 104 and the meter under test 105. The power unit 4 is connected to the first pipe 102 and the second pipe 103 through the air inlet 42 and the air outlet 43 to realize gas circulation, ensure that the gas flow rate in each area is consistent, and thus ensure that the detection environment of multiple flow meters is consistent. The comparison circulation unit 1 is also externally equipped with a leak detection unit 2. The leak detection unit 2 includes a workbench 206. A flow meter 205 is installed on the workbench 206. A leak detection air inlet pipe 306 is connected between the control box 301 and the flow meter 205.

[0033] Please see Figure 1 The first pipe 102 is equipped with multiple support frames 106. The control unit 3 also includes a vacuum pump 302. The vacuum pump 302 and the control box 301 are connected by a connecting pipe, so that the vacuum pump 302 and the comparison circulation unit 1 are connected. The control box 301 is also connected to an air source 303, which consists of an air pump and an air pipe. The air pipe is connected to the control box 301. Through the vacuum pump 302 and the air source 303, both positive and negative pressure detection methods can be used for comparison and leak detection.

[0034] Controlled by the control box 301, the gas source 303 can supply the comparison circulation unit 1 and the leak detection unit 2 with positive pressure, or the gas source 303 can supply the comparison circulation unit 1 and the leak detection unit 2 with negative pressure, so as to meet the requirements of air tightness detection and accuracy comparison of gas ultrasonic flow meters under different pressure conditions and expand the applicable scenarios of the device.

[0035] The comparison cycle unit 1 and the leak detection unit 2 are connected by the control unit 3, so that the two detection processes of leak detection and comparison can be realized simultaneously. The leak detection and comparison functions are controlled by the unified control unit 3. It can be used for leak detection and pressure comparison of various gas flow meters such as gas ultrasonic flow meters, gas rotary flow meters, and gas turbine flow meters. During the comparison, pressure comparison at different pressure points can be realized.

[0036] See Figure 1 , Figure 3 As shown, multiple lifting frames 107 are connected between the first pipe 102 and the second pipe 103. Each lifting frame 107 includes a telescopic rod 1071 and a valve 1072. The telescopic rod 1071 is installed on the first pipe 102, and its telescopic end is fixedly connected to the second pipe 103. The valve 1072 is installed on the telescopic rod 1071. The telescopic rod 1071 is a hydraulic rod. The valve 1072 is used to control the locking of the telescopic rod 1071's extension stroke. When different lengths of the flowmeter to be measured need to be installed, the valve 1072 is first loosened, the extension length of the telescopic rod 1071 is adjusted, and the second pipe 103 is moved vertically. After adjustment, the valve 1072 is tightened to fix the position. This method has stronger adaptability and eliminates the need to replace the special pipe mounting frame for different specifications of the flowmeter to be measured, reducing testing costs and shortening the preparation time before testing.

[0037] Example 2:

[0038] Based on Example 1, see [link / reference] Figure 4 , Figure 5 As shown, a cable interface 46 is installed on the power tank 41, and a motor cable 305 is connected between the cable interface 46 and the control box 301. A support rod 44 is fixedly connected to the power tank 41, and a blind plate 45 is fixedly connected to the power tank 41. A fan 47 is installed inside the power tank 41, and an air outlet and an air inlet are installed on the fan 47. The air outlet and the air inlet are respectively connected to the air outlet 43 and the air inlet 42.

[0039] The power tank 41 of the power unit 4 is fixedly placed on a horizontal ground by a support rod 44. A blind flange 45 seals one side opening of the power tank 41, making it convenient for operators to open the blind flange 45 to maintain and repair the fan 47 inside the power tank 41. The cable interface 46 is connected to the control box 301 through the motor cable 305. The control box 301 transmits power to the fan 47 through the cable and transmits speed control signals at the same time. The speed of the fan 47 is adjusted according to different testing requirements, thereby changing the gas flow rate in the circulation pipeline to match the comparison test requirements under different flow rates.

[0040] Example 3:

[0041] Based on Example 2, see [link / reference] Figure 6 , Figure 7 As shown, the leak detection unit 2 also includes a power box 201, which is driven by hydraulic power. The power box 201 is mounted on the workbench 206, and a top pressure flange 204 is connected to the power box 201. An adjusting wrench 203 for driving the top pressure flange 204 is installed on the power box 201.

[0042] A square groove is provided on the workbench 206. A set of support plates 207 are slidably connected in the square groove. Two support plates 207 are provided and slidably connected in the square groove. The flow meter 205 is installed between the two support plates 207. The top pressure flange 204 cooperates with the flow meter 205 and is used to position and fix the flow meter 205. A slide rail 209 is fixedly connected in the square groove. The support plates 207 are slidably connected to the slide rail 209. A positioning frame 208 is fixedly connected on the workbench 206. A rubber pad 210 is fixedly connected on the positioning frame 208. The rubber pad 210 on the positioning frame 208 can buffer the impact force of the support plate 207 and at the same time prevent the flow meter housing to be tested from directly contacting the rigid positioning frame 208 and causing surface scratches.

[0043] See Figure 6 , Figure 7As shown, a pressure gauge 202 is installed on the power box 201. The pressure gauge 202 is used to display the hydraulic pressure in the power box 201, which allows the operator to adjust the appropriate top pressure according to the specifications of the flow meter 205 being tested. This ensures the sealing reliability between the top pressure flange 204 and the interface of the flow meter being tested, preventing air leakage during the test from affecting the test results. It also prevents excessive top pressure from damaging the housing or interface of the flow meter 205 being tested, thus protecting the tested workpiece from damage. When an individual ultrasonic gas flow meter needs to be tested for air tightness, the flow meter 205 to be tested is placed between two support plates 207. The distance between the two support plates 207 is adjusted along the slide rail 209. After the flow meter 205 is clamped and initially positioned, the support plates 207 are slid along the slide rail 209 in the square groove to move the flow meter 205 to the test position coaxial with the top pressure flange 204. After the positioning frame 208 limits the support plates 207, the adjusting wrench 203 drives the power box 201 to output thrust, pushing the top pressure flange 204 to press the air inlet of the flow meter 205. The clamping and fixing before testing is completed. The clamping process is simple and convenient and can be adapted to clamping and fixing ultrasonic gas flow meters with different outer diameter specifications. During the testing process, the control box 301 introduces test gas at a set pressure into the flow meter 205 under test through the leak test inlet pipe 306. After holding the pressure for a set time, the pressure change is observed to determine whether the air tightness is qualified. After the test is completed, the adjusting wrench 203 is turned in the opposite direction and the top pressure flange 204 is loosened, allowing the flow meter 205 under test to be removed. The entire testing process is independent of the main pipeline of the comparison circulation unit 1, which can pre-screen individual workpieces, reduce the workload caused by unqualified workpieces flowing into the comparison process, and improve the overall testing efficiency.

[0044] When performing a separate airtightness test on the flowmeter under test, first place the flowmeter between the two support plates 207, then slide the two support plates 207 along the slide rail 209 to adjust the flowmeter under test to a position coaxial with the top pressure flange 204. The positioning frame 208 limits the sliding stroke of the support plates 207, and the rubber pad 210 on the positioning frame 208 can buffer the impact force of the support plates 207, while avoiding direct contact between the flowmeter housing and the rigid positioning frame 208 to prevent surface scratches. After the position adjustment is completed, turn the adjusting wrench 2. 03. The transmission mechanism inside the power box 201 pushes the top pressure flange 204 toward the flow meter under test, pressing and sealing the flow meter. Then, the control box 301 introduces test gas at a set pressure into the flow meter 205 under test through the leak test inlet pipe 306. After maintaining the pressure for a certain period of time, the pressure change value is read by the pressure gauge connected to the power box 201, which can determine whether the air tightness of the flow meter under test is qualified. The detection operation is simple and the detection efficiency is high. It can complete the pre-screening of unqualified workpieces before batch comparison, reducing the invalid comparison and detection work.

[0045] In summary, this device integrates both airtightness testing and accuracy comparison of the gas flow meter 205 through a unified control unit 3, eliminating the need to transfer the workpiece between different testing devices, reducing the time spent on transfer and clamping, and resulting in higher overall testing efficiency. The adjustable lifting frame 107 allows for adjustment of the installation position of the meter 105, accommodating the installation needs of flow meters of different lengths. The sliding adjustable support plate 207 allows for clamping and fixing of flow meters with different outer diameters. The device is highly adaptable, eliminating the need for customized clamping fixtures for different flow meter specifications, thus reducing equipment costs. Furthermore, the device can meet the needs of different testing conditions, including positive and negative pressure, and can perform testing on various types of gas flow meters, making it applicable to a wide range of scenarios, offering higher testing accuracy, and better meeting the testing needs of mass production processes.

[0046] The above embodiments are only used to illustrate the technical methods of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical methods of the present invention without departing from the spirit and scope of the technical methods of the present invention.

Claims

1. A gas ultrasonic flow meter air tightness and comparison testing device, comprising a comparison cycle unit (1), characterized in that: The comparison cycle unit (1) is connected to a control unit (3). The control unit (3) includes a control box (301). A comparison cycle air intake pipe (304) is connected between the control box (301) and the comparison cycle unit (1). The comparison cycle unit (1) includes a first pipe (102) and a second pipe (103). The first pipe (102) and the second pipe (103) are connected. The comparison cycle air intake pipe (304) and the second pipe (103) are connected. The comparison cycle unit (1) is provided with a power unit (4) outside. The power unit (4) is provided with an air inlet (42) and an air outlet (43). The air inlet (42) and the air outlet (43) are respectively connected to the first pipe (102) and the second pipe (103). The comparison cycle unit (1) is also provided with a leak detection unit (2). The leak detection unit (2) includes a workbench (206). A flow meter (205) is installed on the workbench (206). A leak detection air inlet pipe (306) is connected between the control box (301) and the flow meter (205).

2. The gas ultrasonic flowmeter airtightness and comparative testing device according to claim 1, characterized in that, The comparison loop unit (1) further includes a standard meter (104) and multiple meters under test (105), both of which are flow meters and are installed on the second pipe (103).

3. The gas ultrasonic flowmeter airtightness and comparative testing device according to claim 1, characterized in that, Multiple lifting frames (107) are connected between the first pipe (102) and the second pipe (103). Each lifting frame (107) includes a telescopic rod (1071) and a valve (1072). The telescopic rod (1071) is installed on the first pipe (102) and its telescopic end is fixedly connected to the second pipe (103). The valve (1072) is installed on the telescopic rod (1071).

4. The gas ultrasonic flowmeter airtightness and comparative testing device according to claim 1, characterized in that, Multiple support frames (106) are installed on the first pipe (102). The control unit (3) also includes a vacuum pump (302). A connecting pipe connects the vacuum pump (302) and the control box (301), so that the vacuum pump (302) and the comparison cycle unit (1) are connected. The control box (301) is also connected to a gas source (303).

5. The gas ultrasonic flowmeter airtightness and comparative testing device according to claim 1, characterized in that, The power unit (4) also includes a power tank (41), on which a cable interface (46) is installed. A motor cable (305) is connected between the cable interface (46) and the control box (301). A support rod (44) is fixedly connected to the power tank (41), and a blind plate (45) is fixedly connected to the power tank (41).

6. The gas ultrasonic flowmeter airtightness and comparative testing device according to claim 5, characterized in that, A fan (47) is installed inside the power tank (41). The fan (47) has an air outlet and an air inlet, which are connected to the air outlet (43) and the air inlet (42) respectively.

7. The gas ultrasonic flowmeter airtightness and comparative testing device according to claim 1, characterized in that, The leak detection unit (2) also includes a power box (201), which is installed on the workbench (206). A top pressure flange (204) is connected to the power box (201). An adjusting wrench (203) for driving the top pressure flange (204) is installed on the power box (201). A pressure gauge (202) is also installed on the power box (201).

8. The gas ultrasonic flowmeter airtightness and comparative testing device according to claim 1, characterized in that, The workbench (206) has a square groove, and a set of support plates (207) are slidably connected in the square groove. The set of support plates (207) consists of two plates that are slidably connected in the square groove.

9. The gas ultrasonic flowmeter airtightness and comparative testing device according to claim 8, characterized in that, The flow meter (205) is installed between two support plates (207), and the top pressure flange (204) is fitted with the flow meter (205).

10. The gas ultrasonic flowmeter airtightness and comparative testing device according to claim 8, characterized in that, A slide rail (209) is fixedly connected inside the square groove. The support plate (207) is slidably connected to the slide rail (209). A positioning frame (208) is fixedly connected to the worktable (206). A rubber pad (210) is fixedly connected to the positioning frame (208).

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