Testing device for testing flow coefficient of flow regulating valve

Abstract

The utility model discloses a testing device for testing the flow coefficient of a flow regulating valve. The testing device comprises a water tank; the flow regulating valve is arranged on the main pipeline; the differential pressure sensor is connected to the main pipeline on the two sides of the flow regulating valve; the pressure difference regulating valve is arranged on the main pipeline; the pneumatic three-way valve is arranged on the main pipeline, an inlet of the pneumatic three-way valve is connected to an outlet of the differential pressure regulating valve, and a first outlet of the pneumatic three-way valve is connected to an inlet of the water tank; the container is connected with a second outlet of the pneumatic three-way valve; and the mass meter is used for measuring the mass of the container. According to the device, a weighing method is adopted for flow measurement, a PLC system is combined for control and data collection, operation of a three-way valve and an auxiliary pump and the rotating speed of the pump are controlled, and signals of a high-precision electronic balance and differential pressure signals of a differential pressure transmitter are collected, so that accurate evaluation of the micro flow regulating valve is achieved.

Description

Technical Field

[0001] This utility model relates to the field of testing equipment for flow regulating valves, and specifically to a testing device for testing the flow coefficient of a flow regulating valve. Background Technology

[0002] A micro-flow regulating valve is a device specifically designed for the precise control of extremely small flow rates of liquids or gases. It is widely used in applications requiring highly precise control of fluid flow rates, encompassing fields such as laboratory research, medical equipment, and fine chemicals. Depending on the specific application and requirements, micro-flow regulating valves can be categorized into several types, primarily including manual and electric regulating valves.

[0003] Manual control valves allow for direct flow control by manually rotating a handle to adjust the valve opening. These valves are simple in structure and relatively inexpensive, making them ideal for applications where flow adjustment frequency is low but a certain level of precision is required.

[0004] In contrast, electric control valves are driven by a motor and can be remotely controlled via a control system to automatically regulate flow. These valves are particularly suitable for applications requiring highly precise control and potentially rapid responses to changes in flow rate.

[0005] Miniature flow control valves, with their ingenious design and high-precision control capabilities, play a crucial role in various applications requiring precise regulation of small flow rates. Their high precision, stability, and reliability make them promising for application in multiple fields.

[0006] In modern industrial production, micro-flow control valves play a crucial role in many precision control applications. To ensure the performance and accuracy of these valves, accurate measurement of their flow coefficients is essential. However, due to the unique characteristics of micro-flow rates, traditional flow measurement methods often fall short in terms of accuracy and reliability. Utility Model Content

[0007] This invention provides a test device for testing the flow coefficient of a flow regulating valve. The device uses a weighing method for flow measurement and integrates a PLC system for control and data acquisition. It controls the operation of the three-way valve, auxiliary pump, and pump speed, and acquires signals from a high-precision electronic balance and a differential pressure transmitter to achieve accurate evaluation of the small flow regulating valve.

[0008] A test apparatus for testing the flow coefficient of a flow regulating valve, comprising:

[0009] A water tank, wherein the outlet and inlet of the water tank are connected in a circulation loop via a main pipeline;

[0010] A flow regulating valve is installed on the main pipeline;

[0011] Differential pressure sensors are connected to the main pipelines on both sides of the flow regulating valve;

[0012] A differential pressure regulating valve is installed on the main pipeline;

[0013] A pneumatic three-way valve is installed on the main pipeline. The inlet of the pneumatic three-way valve is connected to the outlet of the differential pressure regulating valve, and the first outlet of the pneumatic three-way valve is connected to the inlet of the water tank.

[0014] A container connected to the second outlet of the pneumatic three-way valve;

[0015] A mass measuring instrument used to measure the mass of the container.

[0016] A pump is connected to the main pipeline.

[0017] The pump outlet is connected to the main pipeline via a first valve, and the pump outlet is connected to the water tank via a second valve and a return water branch.

[0018] The flow regulating valve, differential pressure regulating valve, and pneumatic three-way valve are arranged sequentially along the flow direction of the main pipeline.

[0019] The main pipeline is equipped with a flexible hose.

[0020] The mass instrument mentioned is an electronic balance, electronic platform scale, electronic weighbridge, force sensor, or mechanical scale.

[0021] A water collection tank is provided below the flow regulating valve.

[0022] The water tank is equipped with a liquid level viewing window.

[0023] The water tank is equipped with a drain outlet.

[0024] In this invention, the automatic valve, pump, electronic balance, and differential pressure transmitter are all connected to the PLC control box and controlled and data acquired by the PLC system. The PLC controls the operation of the three-way valve and the auxiliary pump, as well as the pump speed, and acquires the signals from the high-precision electronic balance and the differential pressure signal from the differential pressure transmitter to achieve accurate evaluation of the micro-flow regulating valve.

[0025] I. Device Structure

[0026] 1.1) Mechanical System:

[0027] 1.1.1) Rack: A rack used to install piping and PLC control boxes;

[0028] 1.1.2) Piping system: including test water tank, test pipeline, auxiliary variable frequency pump, manual valve, valve under test, regulating valve after valve under test, high-precision electronic balance, measuring cylinder, pneumatic three-way valve, differential pressure sensor;

[0029] 1.2) PLC control and data acquisition system:

[0030] 1.2.1) Control System:

[0031] 1.2.1.1) The speed of the variable frequency pump and the opening of the regulating valve after the valve under test are controlled by the PLC to control the flow rate of the test pipeline, so that the pressure difference before and after the valve under test is maintained at about 100 kPa.

[0032] 1.2.1.2) Control the rapid switching of the three-way pneumatic valve;

[0033] 1.2.1.3) After the test is completed, control the pneumatic drain valve on the measuring cylinder to drain the medium from the measuring cylinder;

[0034] 1.2.2) Data Acquisition System:

[0035] 1.2.2.1) High-precision electronic balance: It possesses extremely high measurement accuracy and stability, enabling accurate measurement of fluid mass at different time points. The host computer software communicates with the electronic balance via the RS485 interface of the all-in-one machine, using the Modbus TRU protocol, to accurately read mass data.

[0036] 1.2.2.2) High-precision differential pressure sensors installed before and after the micro-flow regulating valve are capable of acquiring differential pressure data in real time. The differential pressure sensors transmit analog signals to the PLC.

[0037] 1.3) Host computer software system:

[0038] The device is equipped with an industrial all-in-one machine, which contains host computer testing software. Utilizing existing technology, the host computer software communicates with the PLC to read data from the PLC and displays measurement results in real time, including flow rate and flow coefficient (KV value) calculated from differential pressure. The testing software internally uses a polynomial fitting algorithm to plot the KV value-valve opening curve, ultimately generating a KV test report for the micro-flow regulating valve, which is automatically saved to the all-in-one machine's hard drive.

[0039] II. Working Principle

[0040] 2.1) Flow measurement:

[0041] 2.1.1) Pressure difference control across the valve under test: Start the auxiliary pump, control the pump speed by frequency conversion or adjust the regulating valve after the valve under test to adjust the flow rate so that the pressure difference across the valve under test is maintained at about 100 kPa.

[0042] 2.1.2) Once the balance data is stable, begin the test and record the initial mass of the electronic balance. Simultaneously, automatically switch the three-way valve to introduce fluid into the graduated cylinder above the balance;

[0043] 2.1.3) As the fluid flows into the container through the micro-flow regulating valve, the electronic balance continuously monitors the changes in mass.

[0044] 2.1.4) When the end measurement time is reached, record the final mass of the electronic balance. At the same time, automatically switch the three-way valve to introduce fluid into the test water tank; calculate the fluid flow rate by using the mass difference and the measurement time interval.

[0045] 2.2) Differential pressure acquisition:

[0046] 2.2.1) The pressure sensor monitors the pressure changes before and after the micro-flow regulating valve in real time and transmits the differential pressure data to the PLC's data processing unit.

[0047] 2.3) Flow coefficient calculation:

[0048] 2.3.1) The data processing unit calculates the flow coefficient (KV value) of the micro flow control valve using a specific calculation formula based on the flow measurement results and differential pressure data.

[0049] Compared with the prior art, the present invention has the following advantages:

[0050] 1. High-precision measurement: By using the weighing method combined with a high-precision electronic balance, it is possible to accurately measure minute flow rates, which greatly improves the accuracy of flow coefficient calculation.

[0051] 2. Reliable differential pressure acquisition: Advanced differential pressure sensors and data transmission technology ensure the accuracy and reliability of differential pressure data, providing a solid foundation for the calculation of flow coefficient.

[0052] 3. Intuitive result display: The integrated machine displays the measurement results in real time, allowing operators to intuitively understand the performance of the micro-flow regulating valve, which is convenient for analysis and evaluation.

[0053] 4. Easy to operate: The entire test device is reasonably designed and easy to operate. It can complete the test of micro-flow regulating valves without complicated operating procedures or professional skills.

[0054] 5. Wide applicability: Applicable to testing of various specifications and types of micro-flow regulating valves, with strong versatility. Attached Figure Description

[0055] Figure 1 This is a schematic diagram of the test device for testing the flow coefficient of a flow regulating valve according to this utility model.

[0056] Figure 2 This is a schematic diagram of the test device for testing the flow coefficient of a flow regulating valve according to this utility model. Detailed Implementation

[0057] The following is a detailed description of the test apparatus for testing the flow coefficient of the flow regulating valve according to this utility model, with reference to the accompanying drawings.

[0058] like Figure 1 and Figure 2 As shown, a test apparatus for testing the flow coefficient of a flow regulating valve includes: a water tank 2, the outlet and inlet of which are circulated through a main pipeline; a micro-flow regulating valve 9 installed on the main pipeline; differential pressure sensors 21 connected to both sides of the micro-flow regulating valve 9 on the main pipeline; a differential pressure regulating valve (i.e., downstream regulating valve 11) installed on the main pipeline; a pneumatic three-way valve 13 installed on the main pipeline, the inlet of which is connected to the outlet of the differential pressure regulating valve (i.e., downstream regulating valve 11), and the first outlet of which is connected to the inlet of the water tank 2; a container (specifically a measuring cylinder 14) connected to the second outlet of the pneumatic three-way valve; and a mass measuring instrument (specifically an electronic balance 15) for measuring the mass of the container. A pump (specifically an auxiliary pump 4) is connected to the main pipeline. The outlet of the auxiliary pump 4 is connected to the main pipeline through a first valve 3 (specifically a first manual valve), and the outlet of the auxiliary pump 4 is connected to the water tank 2 through a second valve 5 (specifically a second manual valve) and a return water branch. The micro-flow regulating valve 9, the differential pressure regulating valve (i.e., the downstream regulating valve 11), and the pneumatic three-way valve 12 are arranged sequentially along the flow direction of the main pipeline. A flexible hose is installed on the main pipeline. A water collection tank 7 is located below the micro-flow regulating valve. A liquid level viewing window 22 is provided on the water tank 2. A drain port 23 is provided on the water tank 2.

[0059] like Figure 2As shown, frame 1 is used to install the piping system and electrical system; water tank 2 is used to hold the test medium; first manual valve 3 is used to switch the water tank and pump inlet on and off; auxiliary pump 4 is a variable frequency centrifugal pump, providing the flow and pressure required for the test; second manual valve 5: adjusts different opening degrees to control the pump outlet flow, returning to water tank 2; third manual valve 6: adjusts different opening degrees to control the pump outlet flow, to the test pipeline; water collection tank 7 is used to collect the medium in the test pipeline when disassembling and assembling the valve under test, and return it to water tank 2; pressure tapping interface 8 before the valve is used to connect to the high-pressure side interface of the differential pressure sensor (i.e., the regulating valve 11 after the valve); micro-flow regulating valve 9 is the test object, the valve under test; pressure tapping interface 10 after the valve is used to connect to the low-pressure side interface of the differential pressure sensor (i.e., the regulating valve 11 after the valve). The downstream regulating valve 11 is installed downstream of the valve under test and is used to control the downstream pressure of the valve under test, together with the frequency of the auxiliary pump to control the differential pressure of the valve under test; the pneumatic two-way valve 12 is installed at the bottom of the measuring cylinder and is used to discharge the medium in the measuring cylinder into the water collection tank after the test, and finally return to the test water tank; the pneumatic three-way valve 13 is a key component and is used to quickly switch the direction of medium flow; the measuring cylinder 14 is used to hold the test medium; the balance 15 is used to measure the mass of the measuring cylinder 14 and the accessories installed on the measuring cylinder 14 and the test medium; the PLC control box 16 houses the PLC control and acquisition system; the industrial all-in-one machine 17 serves as the human-machine interface and is installed on the PLC control box 16; the indicator light 18 indicates the system is powered on and running; the rotary switch 19 is used for system power-on and power-off operations; the balance bracket 20 is used to fix the balance, and the balance bracket 20 does not contact the frame 1 to prevent the vibration generated by the operation of the auxiliary pump 4 from affecting the stability of the balance measurement data.

[0060] I. Equipment Installation and Commissioning:

[0061] 1. Install and debug all components of the test apparatus to ensure that the electronic balance, differential pressure sensor, PLC control and acquisition system, and host computer software are working properly.

[0062] 2. Check the sealing of the liquid container to prevent fluid leakage.

[0063] II. Test Preparation:

[0064] 1. Install the micro-flow regulating valve to be tested on the test pipeline, and connect the control and feedback signal lines of the valve to be tested to the PLC system.

[0065] 2. Inject an appropriate amount of the fluid to be tested into the test water tank, and ensure that the electronic balance is properly connected to the communication system so that it can accurately measure the mass.

[0066] III. Start the test:

[0067] 1. Set the start and end measurement times, and click the "Start" button. The host computer software will automatically control the test process.

[0068] 2. When the measurement time ends, record the mass data of the electronic balance, stop the data acquisition of the pressure sensor, and stop the operation of the auxiliary pump.

[0069] 3. The host computer software receives and processes data from the electronic balance, time control module and differential pressure sensor, and calculates the flow rate and flow coefficient (KV value).

[0070] IV. Results Analysis and Evaluation:

[0071] 1. Observe the measurement results on the display screen and analyze whether the performance of the micro-flow regulating valve meets the requirements.

[0072] 2. Multiple tests can be performed, and the average value can be taken to improve the accuracy and reliability of the test results.

[0073] In summary, the test device for testing the flow coefficient of a micro-flow regulating valve provided by this utility model highly integrates mechanical, electrical, and software components, and has a compact overall structure. By employing the weighing method to measure flow rate, a high-precision electronic balance, and advanced differential pressure acquisition technology, it provides an accurate, reliable, and easy-to-operate solution for the performance evaluation of micro-flow regulating valves.

[0074] The specific embodiments described above provide a detailed explanation of the technical solution and beneficial effects of this utility model. It should be understood that the above description is only the most preferred embodiment of this utility model and is not intended to limit this utility model. Any modifications, additions, and equivalent substitutions made within the scope of the principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A test apparatus for testing the flow coefficient of a flow regulating valve, characterized in that, include: A water tank, wherein the outlet and inlet of the water tank are connected in a circulation loop via a main pipeline; A flow regulating valve is installed on the main pipeline; Differential pressure sensors are connected to the main pipelines on both sides of the flow regulating valve; A differential pressure regulating valve is installed on the main pipeline; A pneumatic three-way valve is installed on the main pipeline. The inlet of the pneumatic three-way valve is connected to the outlet of the differential pressure regulating valve, and the first outlet of the pneumatic three-way valve is connected to the inlet of the water tank. A container connected to the second outlet of the pneumatic three-way valve; A mass measuring instrument used to measure the mass of the container.

2. The test apparatus for testing the flow coefficient of a flow regulating valve according to claim 1, characterized in that, A pump is connected to the main pipeline.

3. The test apparatus for testing the flow coefficient of a flow regulating valve according to claim 2, characterized in that, The pump outlet is connected to the main pipeline via a first valve, and the pump outlet is connected to the water tank via a second valve and a return water branch.

4. The test apparatus for testing the flow coefficient of a flow regulating valve according to claim 1, characterized in that, The flow regulating valve, differential pressure regulating valve, and pneumatic three-way valve are arranged sequentially along the flow direction of the main pipeline.

5. The test apparatus for testing the flow coefficient of a flow regulating valve according to claim 1, characterized in that, The main pipeline is equipped with a flexible hose.

6. The test apparatus for testing the flow coefficient of a flow regulating valve according to claim 1, characterized in that, The mass instrument mentioned is an electronic balance, or an electronic platform scale, an electronic weighbridge, a force sensor, or a mechanical scale.

7. The test apparatus for testing the flow coefficient of a flow regulating valve according to claim 1, characterized in that, A water collection tank is provided below the flow regulating valve.

8. The test apparatus for testing the flow coefficient of a flow regulating valve according to claim 1, characterized in that, The water tank is equipped with a liquid level viewing window.

9. The test apparatus for testing the flow coefficient of a flow regulating valve according to claim 1, characterized in that, The water tank is equipped with a drain outlet.

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