Pipeline system for water meter flow calibration and automatic flow regulation method

Abstract

The present invention belongs to the technical field of water meter calibration. A pipeline system and automatic flow regulation method for water meter flow calibration are proposed, including: a pressure-stabilizing tank, a water pump with a frequency converter, at least one first pipeline greater than a set caliber threshold, and at least one second pipeline less than a set caliber threshold, the water pump is connected to the pressure-stabilizing tank through a pipeline, and the first pipeline and the second pipeline are respectively connected to the pressure-stabilizing tank; the present invention can be applied to flow calibration of different calibers, and the process of flow point adjustment is combined with water pump frequency conversion, regulating valve opening adjustment and instantaneous flow feedback from an electromagnetic flowmeter to automatically adjust the flow point, effectively reducing the user's operating difficulty and reducing the user's learning cost.

Description

Technical Field

[0001] The invention relates to the technical field of water meter calibration, and in particular to a pipeline system and an automatic flow regulating method for water meter flow calibration. Background Art

[0002] The statements in this section merely provide background art related to the present invention and do not necessarily constitute prior art.

[0003] During the water meter calibration process, it is necessary to perform error calibration on different flow points of the water meter (common flow Q3, boundary flow Q2, minimum flow Q1, R value = Q3 / Q1, Q2 = 1.6Q1). During the calibration process of small-diameter water meters (such as water meters below DN50), manual ball valves combined with glass rotor flowmeters are more often used to manually adjust each flow point.

[0004] However, in the case of large-diameter water meters (such as water meters above DN50), as the pressure-stabilizing tank becomes larger, the water volume of the entire water circulation system also increases. The pressure-stabilizing tank is 12 cubic meters or more, so a very long waiting period is required for flow stabilization, and the workload of manual adjustment is particularly large. In addition, as the valve becomes larger, it is particularly laborious to manually adjust the valve using the traditional method. Summary of the invention

[0005] In order to address the deficiencies in the prior art, the present invention provides a pipeline system and an automatic flow regulation method for water meter flow calibration, which are suitable for flow calibration of different calibers. The flow point adjustment process is combined with water pump frequency conversion, regulating valve opening adjustment and instantaneous flow feedback from the electromagnetic flowmeter to automatically adjust the flow point, effectively reducing the user's operating difficulty and reducing the user's learning cost.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a piping system for water meter flow calibration.

[0008] A pipeline system for water meter flow calibration, comprising: a pressure stabilizing tank, a water pump with a frequency converter, at least one first pipeline with a diameter greater than a set threshold value, and at least one second pipeline with a diameter less than the set threshold value, wherein the water pump is connected to the pressure stabilizing tank through a pipeline, and the first pipeline and the second pipeline are respectively connected to the pressure stabilizing tank;

[0009] The first pipeline is provided with a first pneumatic valve, a flow meter and an electric regulating valve in sequence, the main pipeline of the second pipeline is connected with a first manual valve, a second pneumatic valve, a flow meter and a regulating valve in sequence, a sub-pipeline is provided in parallel with the first manual valve and the second pneumatic valve on the main pipeline, and the second manual valve and the third pneumatic valve are provided on the sub-pipeline in sequence.

[0010] As a further limitation of the first aspect of the present invention, the first pneumatic valve is a pneumatic ball valve or a pneumatic butterfly valve.

[0011] As a further limitation of the first aspect of the present invention, the first manual valve is a manual ball valve, and the second pneumatic valve is a pneumatic ball valve.

[0012] As a further limitation of the first aspect of the present invention, the flow meter is an electromagnetic flow meter, and the regulating valve is a pneumatic regulating valve or an electric regulating valve.

[0013] As a further limitation of the first aspect of the present invention, the first pipeline includes a plurality of sub-pipelines, and each sub-pipeline has a different caliber; the second pipeline includes a plurality of sub-pipelines, and each sub-pipeline has a different caliber.

[0014] As a further limitation of the first aspect of the present invention, the water pumps with frequency converters include a plurality of water pumps, and the plurality of water pumps are respectively connected to the pressure-stabilizing tank through pipelines.

[0015] In a second aspect, the present invention provides an automatic flow regulation method.

[0016] An automatic flow rate regulation method, using the pipeline system for water meter flow rate verification according to the first aspect of the present invention, comprises:

[0017] According to the caliber, Q3 flow point and R value of the water meter to be tested, the Q2 flow point and Q1 flow point are automatically calculated. The Q1 flow point is the minimum flow value that the water meter can accurately measure, the Q2 flow point is the boundary flow point, the Q3 flow point is the common flow point, and the R value is the ratio of the common flow Q3 to the minimum flow Q1. According to different flow points, the corresponding pipeline, water pump, regulating valve and flow meter are selected to perform the following four-stage adjustment process. After any stage meets the flow adjustment requirements, the adjustment process is interrupted and completed:

[0018] Process 1: Adjust the regulating valve and water pump to the preset opening;

[0019] Process 2: Perform coarse adjustment of the regulating valve;

[0020] Process 3: Fine-tune the regulating valve;

[0021] Step 4: Fine-tune the inverter.

[0022] As a further limitation of the second aspect of the present invention, adjusting the regulating valve and the water pump to a preset opening degree includes:

[0023] Select the specific water pump to be used according to the target flow rate, and adjust the regulating valve and inverter to the preset values;

[0024] If the current pipeline is not the one with the largest diameter, open the pipeline with the largest diameter and turn the regulating valve of the largest pipeline fully open to release the pressure in the pressure stabilizing tank. After judging that the pressure in the pressure stabilizing tank is stable, close it.

[0025] After the pressure relief process is completed, wait for the pressure and flow rate to return to the balanced state again.

[0026] As a further limitation of the second aspect of the present invention, the rough adjustment of the regulating valve includes:

[0027] After judging that the pressure is stable, judge the magnitude of the flow rate. If the flow rate does not meet the target flow rate, enter the rough adjustment stage. The regulating valve is adjusted from small to large, with the opening increased by 3% each time, until the flow velocity is higher than the target lower limit.

[0028] The fine adjustment of the regulating valve includes:

[0029] Judge the magnitude of the flow rate. If the flow rate meets the target flow rate, end the adjustment process. The regulating valve is adjusted from large to small, with the opening decreased by 1% each time, until the flow velocity is lower than the target upper limit.

[0030] As a further limitation of the second aspect of the present invention, the fine adjustment of the frequency converter includes:

[0031] Record the current flow velocity and frequency, denoted as v1 and f1. Increase the frequency of the frequency converter by 5 Hz, wait for a period of time and then record the flow velocity and frequency again, denoted as v2 and f2.

[0032] Linearly calculate the target frequency f = (v - v1) / (v2 - v1)*(f2 - f1) + f1 from the target flow velocity v.

[0033] If f < f2, repeat the process of releasing the pressure in the pressure stabilizing tank and waiting for the pressure and flow rate to return to the balanced state in process 1. Wait for a period of time and then record the flow velocity again, denoted as v3.

[0034] If the flow velocity v3 is lower than the target lower limit, calculate the new frequency f' = (v - v3) / (v2 - v1)*(f2 - 1) + f again.

[0035] Repeat the above process until the target flow rate range is satisfied.

[0036] Compared with the prior art, the beneficial effects of the present invention are:

[0037] 1. The present invention innovatively proposes a pipeline system for water meter flow rate verification, including: a pressure stabilizing tank, a water pump with a frequency converter, at least one first pipeline with a diameter larger than the set diameter threshold, and at least one second pipeline with a diameter smaller than the set diameter threshold. The water pump is connected to the pressure stabilizing tank through a pipeline, and the first pipeline and the second pipeline are respectively connected to the pressure stabilizing tank, which is applicable to the flow rate verification of different diameters.

[0038] 2. The present invention innovatively proposes an automatic flow regulation method, which performs the regulation process in the following four stages (adjusting the regulating valve and the water pump to the preset opening, performing rough adjustment of the regulating valve, performing fine adjustment of the regulating valve, and performing fine adjustment of the frequency converter). After any stage meets the flow regulation requirements, the regulation process is interrupted. By combining the process of adjusting the flow point with the frequency conversion of the water pump, the opening adjustment of the regulating valve, and the instantaneous flow rate fed back by the electromagnetic flowmeter, the flow point is automatically adjusted, effectively reducing the operation difficulty of users and the learning cost of users.

[0039] 3. The present invention innovatively proposes to perform fine adjustment of the frequency converter, record the current flow velocity and frequency, denoted as v1 and f1, increase the frequency of the frequency converter by 5 Hz, wait for a period of time and then record the flow velocity and frequency again, denoted as v2 and f2; linearly calculate the target frequency f = (v - v1) / (v2 - v1)*(f2 - f1) + f1 from the target flow velocity v; if f < f2, repeat the process of releasing the pressure of the pressure stabilizing tank and waiting for the pressure and flow rate to return to the balanced state in process 1, wait for a period of time and then record the flow velocity again, denoted as v3; if the flow velocity v3 is lower than the target lower limit, calculate the new frequency f' = (v - v3) / (v2 - v1)*(f2 - 1) + f again, and repeat the above process until the target flow range is met, realizing more accurate flow velocity regulation and being applicable to the scenario of small flow rates that are difficult to regulate.

[0040] Advantages of additional aspects of the present invention will be partially given in the following description, partially become obvious from the following description, or be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings forming a part of this specification are used to provide a further understanding of the present invention. The schematic embodiments and descriptions thereof of the present invention are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0042] Figure 1 It is a schematic diagram of the pipeline system for water meter flow rate verification provided by the present invention;

[0043] Figure 2 It is a schematic diagram of the automatic flow regulation method provided by the present invention;

[0044] Among them, 1. The first pneumatic valve; 2. The flowmeter; 3. The electric regulating valve; 4. The valve group. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0046] It should be noted that the following detailed description is exemplary and is intended to provide further description of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0047] In the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0048] Embodiment 1:

[0049] In this implementation, if Figure 1 As shown, a pipeline system for water meter flow calibration is proposed, comprising: a pressure stabilizing tank, a water pump with a frequency converter, at least one first pipeline with a diameter greater than a set threshold value, and at least one second pipeline with a diameter less than the set threshold value, wherein the water pump is connected to the pressure stabilizing tank through a pipeline, and the first pipeline and the second pipeline are respectively connected to the pressure stabilizing tank;

[0050] The first pipeline is provided with a first pneumatic valve, a flow meter and an electric regulating valve in sequence, the main pipeline of the second pipeline is connected with a valve group (including a first manual valve and a second pneumatic valve connected in series in sequence), a flow meter and a regulating valve in sequence, a sub-pipeline is provided in parallel with the first manual valve and the second pneumatic valve on the main pipeline, and a valve group (including a second manual valve and a third pneumatic valve connected in series in sequence) is provided on the sub-pipeline in sequence.

[0051] In this implementation, preferably, the first pneumatic valve is a pneumatic ball valve or a pneumatic butterfly valve; the first manual valve is a manual ball valve, and the second pneumatic valve is a pneumatic ball valve.

[0052] In this implementation, preferably, the flow meter is an electromagnetic flow meter, and the regulating valve is a pneumatic regulating valve or an electric regulating valve.

[0053] In this implementation, preferably, the first pipeline includes multiple sub-pipelines, and the caliber of each sub-pipeline is different (DN150 and DN300 are preferred in this implementation); the second pipeline includes multiple sub-pipelines, and the caliber of each sub-pipeline is different (DN10, DN32 and DN100 are preferred in this implementation), and the caliber threshold here is set to DN100; it can be understood that the caliber threshold here can also be selected according to the specific working conditions, for example, DN32 can also be selected, which will not be repeated here.

[0054] In this implementation, preferably, the water pumps with frequency converters include multiple ones, and the multiple water pumps are respectively connected to the pressure-stabilizing tank through pipelines.

[0055] In this implementation, multiple water pumps with different power and head (each water pump corresponds to a frequency converter) supply water to a pressure-stabilizing tank, and the pressure-stabilizing tank supplies water to the water meter calibration pipeline. Different pipelines are used to clamp water meters of different calibers, and different pipelines are used to operate different flow points.

[0056] The electric control valve or pneumatic control valve in this implementation adopts a 4-20ma signal to drive the valve opening, thereby automatically adjusting the flow rate; the electromagnetic flowmeter in this implementation adopts a pulse output form to indicate the instantaneous flow rate and cumulative flow rate of the pipeline. Electromagnetic flowmeters of different calibers (DN10-DN300) indicate different flow ranges.

[0057] In this implementation, pipelines below DN100 are equipped with pneumatic ball valves and manual ball valves. Each pipeline is divided into two small branches. When the water meter has a small flow point (Q2 and Q1), different flow points may need to share an electromagnetic flow meter. However, it is hoped that after the manual ball valve is used to adjust the flow, the pneumatic ball valve can be used to automatically switch the flow points at different flow point values, eliminating the flow adjustment process when switching the water meter. Pipelines above DN150 are only equipped with pneumatic butterfly valves or ball valves for on-off control of the pipeline.

[0058] In this implementation, when the water meter is calibrated, the Q2 and Q1 flow points are automatically calculated according to the caliber, Q3 flow point and R value input by the user, and the water pump, corresponding pipeline and electric (or pneumatic) regulating valve, and electromagnetic flow meter are automatically selected at different flow points to reduce the complexity of user calculation and selection. Among them, Q1 (minimum flow) represents the minimum flow value that the water meter can accurately measure; Q2 (dividing flow) represents the flow value of the water meter from the start to a certain flow range, and its error does not exceed the maximum allowable positive and negative error limit. Q2 is set to 1.6 times the minimum flow Q1, that is, Q2 = 1.6Q1; Q3 (common flow) represents the flow value frequently used by the water meter under normal working conditions; R value represents the ratio of the common flow Q3 to the minimum flow Q1, that is, R = Q3 / Q1.

[0059] In this implementation, for scenarios where small flows are difficult to adjust, the smallest water pump is selected to achieve more precise adjustment of small flows; for flow points that are particularly small and difficult to adjust, and for situations where different flow points need to share an electromagnetic flowmeter, the manual ball valve design is retained.

[0060] A more specific automatic flow regulation method is divided into four stages. Once any stage meets the flow regulation requirements, the regulation process can be interrupted at any time:

[0061] Stage 1: Preset opening stage (adjust the electric control valve and water pump to the preset opening).

[0062] 1.1: Adjust the valve and inverter (multiple pumps may be used at the same time) to the preset value. At this stage, select the specific water pump to be used according to the target flow rate. Multiple water pumps may need to be used at the same time;

[0063] 1.2: Pressure balance stage: If the current pipeline is not the largest pipeline, open the largest pipeline and turn the regulating valve of the largest pipeline to the maximum to release the pressure in the pressure stabilizing tank. After judging that the pressure in the pressure stabilizing tank is stable, close it.

[0064] 1.3: After the pressure relief process is completed, wait for the pressure and flow rate to return to the balanced state again.

[0065] Stage 2: Coarse adjustment stage of the electric regulating valve.

[0066] 2.1: After judging that the pressure is stable, judge the flow rate. If the flow rate does not meet the target flow rate, enter the coarse adjustment stage.

[0067] 2.2: The regulating valve is adjusted from small to large, increasing the opening by 3% each time until the flow velocity is higher than the target lower limit.

[0068] Stage 3: Fine adjustment stage of the electric regulating valve.

[0069] 3.1: Judge the flow rate. If the flow rate meets the target flow rate, end the adjustment process.

[0070] 3.2: The regulating valve is adjusted from large to small, decreasing the opening by 1% each time until the flow velocity is lower than the target upper limit.

[0071] Stage 4: Fine adjustment stage of the frequency converter.

[0072] When the above Stage 1 - Stage 3 are completed and the flow rate cannot be adjusted to the target flow rate range, enter the frequency converter adjustment stage, including:

[0073] 4.1: Record the current flow velocity and frequency, denoted as v1 and f1. Increase the frequency of the frequency converter by 5Hz, wait for a period of time and then record the flow velocity and frequency again, denoted as v2 and f2.

[0074] 4.2: Linearly calculate the target frequency f = (v - v1) / (v2 - v1)*(f2 - f1)+f1 from the target flow velocity v.

[0075] 4.3: If f < f2, repeat the process of releasing the pressure in the pressure stabilizing tank and waiting for the pressure and flow rate to return to the balanced state in process 1, wait for a period of time and then record the flow velocity again, denoted as v3.

[0076] 4.4: If the flow velocity v3 is lower than the target lower limit, calculate the new frequency f′ = (v - v3) / (v2 - v1)*

[0077] (f2 - 1)+f;

[0078] 4.5: Repeat the above process until the target flow rate range is satisfied.

[0079] After the automatic flow adjustment is completed, the rationality of the flow point will be automatically checked. If the extremely small flow cannot meet the situation, the user will be automatically prompted to fine-tune the manual ball valve. After all flow points are automatically adjusted, the last adjustment result will be automatically recorded as the initial calibration opening for the re-calibration of the same model water meter, thereby saving the flow adjustment time for the same model water meter.

[0080] 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 variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A piping system for water meter flow calibration, characterized in that: include: A pressure stabilizing tank, a water pump with a frequency converter, at least one first pipeline with a diameter greater than a set threshold value, and at least one second pipeline with a diameter less than a set threshold value, wherein the water pump is connected to the pressure stabilizing tank through a pipeline, and the first pipeline and the second pipeline are respectively connected to the pressure stabilizing tank; The first pipeline is provided with a first pneumatic valve, a flow meter and an electric regulating valve in sequence, the main pipeline of the second pipeline is connected with a first manual valve, a second pneumatic valve, a flow meter and a regulating valve in sequence, a sub-pipeline is provided in parallel with the first manual valve and the second pneumatic valve on the main pipeline, and the second manual valve and the third pneumatic valve are provided on the sub-pipeline in sequence.

2. The piping system for water meter flow calibration as claimed in claim 1, characterized in that: The first pneumatic valve is a pneumatic ball valve or a pneumatic butterfly valve.

3. The piping system for water meter flow calibration according to claim 1, characterized in that: The first manual valve is a manual ball valve, and the second pneumatic valve is a pneumatic ball valve.

4. The piping system for water meter flow calibration according to claim 1, characterized in that: The flow meter is an electromagnetic flow meter, and the regulating valve is a pneumatic regulating valve or an electric regulating valve.

5. The piping system for water meter flow calibration according to any one of claims 1 to 4, characterized in that: The first pipeline includes a plurality of sub-pipelines, and the calibers of the sub-pipelines are different; the second pipeline includes a plurality of sub-pipelines, and the calibers of the sub-pipelines are different.

6. The piping system for water meter flow calibration according to any one of claims 1 to 4, characterized in that: The water pumps with frequency converters include a plurality of water pumps, which are respectively connected to the pressure-stabilizing tank through pipelines.

7. An automatic flow regulation method, characterized in that: A piping system for water meter flow calibration using any one of claims 1 to 5, comprising: According to the caliber, Q3 flow point and R value of the water meter to be tested, the Q2 flow point and Q1 flow point are automatically calculated. The Q1 flow point is the minimum flow value that the water meter can accurately measure, the Q2 flow point is the boundary flow point, the Q3 flow point is the common flow point, and the R value is the ratio of the common flow Q3 to the minimum flow Q1. According to different flow points, the corresponding pipeline, water pump, regulating valve and flow meter are selected to perform the following four-stage adjustment process. After any stage meets the flow adjustment requirements, the adjustment process is interrupted and completed: Process 1: Adjust the regulating valve and water pump to the preset opening; Process 2: Perform coarse adjustment of the regulating valve; Process 3: Fine-tune the regulating valve; Step 4: Fine-tune the inverter.

8. The automatic flow regulation method according to claim 7, characterized in that: Adjust the regulating valve and water pump to the preset opening, including: Select the specific water pump to be used according to the target flow rate, and adjust the regulating valve and inverter to the preset values; If the current pipeline is not the pipeline with the largest diameter, open the largest pipeline and open the regulating valve of the largest pipeline to the maximum to release the pressure of the pressure regulating tank. After judging that the pressure of the pressure regulating tank is stable, close it. After the pressure relief process is completed, wait for the pressure and flow to return to a balanced state.

9. The automatic flow regulation method according to claim 8, characterized in that: Coarse adjustment of the regulating valve is performed, including: After the pressure is judged to be stable, judge the flow rate. If the flow rate does not meet the target flow rate, enter the coarse adjustment stage. The regulating valve is adjusted from small to large, increasing the opening by 3% each time until the flow velocity is higher than the target lower limit; Fine adjustment of the regulating valve is performed, including: Judge the flow rate. If the flow rate meets the target flow rate, end the adjustment process. The regulating valve is adjusted from large to small, decreasing the opening by 1% each time until the flow velocity is lower than the target upper limit.

10. The automatic flow rate adjustment method according to claim 9, characterized in that Fine adjustment of the frequency converter is performed, including: Record the current flow velocity and frequency, denoted as v1 and f1. Increase the frequency of the frequency converter by 5 Hz, wait for a period of time and then record the flow velocity and frequency again, denoted as v2 and f2; Linearly calculate the target frequency f = (v - v1) / (v2 - v1)*(f2 - f1)+f1 from the target flow velocity v; If f < f2, repeat the process of releasing the pressure in the pressure stabilizing tank and waiting for the pressure and flow rate to return to the balanced state in process 1, wait for a period of time and then record the flow velocity again, denoted as v3; If the flow velocity v3 is lower than the target lower limit, calculate the new frequency f' = (v - v3) / (v2 - v1)*(f2 - 1)+f again; Repeat the above process until the target flow rate range is satisfied.

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