CN201364194Y - Liquid flow test device - Google Patents

Abstract

The utility model relates to a liquid flow test device, wherein the test channel of the test device is a sealed channel with liquid flowing inside, and the test channel is provided with a pressure-stabilizing liquid source 4, a pressure transmitter 9, a meter position to be tested 10, a pressure transmitter 11, a high-precision automatic regulating valve 13, an electromagnetic flowmeter 15, etc., and a volumetric method test device and a mass method test device composed of a mode conversion valve A16, a commutator 18, a standard measuring device 19, and an electronic weighing device 21 in order. The signal acquisition and control of the liquid flow in the test channel are realized by a PLC arranged in a built-in electric control box 24, and the data exchange and processing of the flow signal in the test channel are realized by a CPU arranged in a touch screen 14, and the touch screen 14 controls and displays the results of the data exchange and processing. The utility model relates to a liquid flow test device having four detection methods integrated into one.

Description

A liquid flow test device

technical field

The utility model relates to a liquid flow test device. More specifically, the utility model detects the flow of liquid based on the pressure difference generated by the detection throttling device, and can be detected or verified by the volumetric method or the mass method. device.

Background technique

As we all know, the traditional liquid test device is that the liquid flow passes through the throttling piece to be tested and enters the standard measuring device. When a certain water level is reached, the control valve is closed, and the indicated value of the standard measuring device is read and compared with the count of the throttled piece to be tested. This method determines the indication error of the throttling part to be checked. The advantage of this method is that it is simple, convenient, accurate and reliable. The disadvantage is that the detection time is long and the detection efficiency is low. With the development of electronic technology and sensor technology, a fluid dynamic differential pressure detection method has become very mature. Its principle is that when the fluid passes through the throttle in the pipeline, the fluid will form a local contraction at the throttle. As a result, the flow rate increases and the static pressure decreases, so a pressure difference is generated before and after the throttled part to be tested. The pressure difference between the front and rear of the throttled part to be tested is used to detect the pressure difference, thereby measuring the flow rate. The Chinese patent with publication number CN2729662Y (application number is 200420069540.7) discloses a dynamic automatic detection device for serial water meters. It is composed of a stabilized water source, a test pipe section, a standard flow sensor, a control valve, a photoelectric signal sampler, a signal acquisition control and a computer data processing system. The water flows from the stabilized water source through the test pipe section and flows through the tested meter, standard flow sensor and control valve in sequence. When the water flow is stable, the signal acquisition controller dynamically and synchronously collects the flow signals of the checked throttling parts and the standard flow sensor and transmits them to the computer system for data processing, and the test results automatically form a report. The beneficial effect of the patent is to realize the dynamic automatic detection of the throttling parts to be inspected, and has the characteristics of high efficiency and low cost. However, this device has disadvantages such as poor reliability and accuracy, single function, difficult calibration of standard flow sensors, blockage, leakage, corrosion, and signal distortion caused by the pressure pipeline, which easily affect the test accuracy.

Contents of the invention

In order to overcome the above-mentioned shortcomings of the prior art, the utility model provides a liquid flow test device, which has the following functions: one is to measure the pressure difference by preset flow rate; the other is to measure the flow rate by preset pressure difference; It is a multi-functional liquid flow test device integrating four methods of flow measurement.

The technical scheme of the utility model to achieve the above object is: a liquid flow test device, the test channel of the test device is a sealed channel with liquid flow inside, and the pressure-stabilizing liquid source, temperature Transmitters, electromagnetic switch valves, pressure transmitters, clamps, pressure transmitters, tested gauges, pressure transmitters, pressure transmitters, high-precision automatic regulating valves, electromagnetic flowmeters, are set in The PLC in the built-in electric control box realizes the signal acquisition and control of the liquid flow in the test channel, and the CPU in the touch screen realizes the data exchange and processing of the flow signal in the test channel, and the touch screen controls and displays the data The results of the exchange and processing are characterized in that: the test channel is also provided with a volumetric test device consisting of a mode switching valve A, a commutator, and a standard gauge; , standard measuring device, and electronic weighing device.

A mode switching valve B is arranged between the electromagnetic flowmeter and the mode switching valve A.

The signal acquisition and control of the liquid flow in the volumetric test device and the mass method test device are realized by the PLC arranged in the built-in electric control box.

The data exchange and processing of the liquid flow signals in the volumetric test device and the mass method test device are realized by the CPU arranged on the touch screen, and the touch screen displays the results of the data exchange and processing.

There are at least two standard measuring instruments.

Compared with the prior art, the present invention has the advantages that: the whole set of liquid flow test device has a pressure transmitter, an electromagnetic flowmeter, a standard measuring device and an electronic weighing device and a weighing device to form a sampling system to form four test methods. Not only the standard meter method can be used to test the throttle, but also the volume method and mass method can be used to test the meter and calibrate the standard electromagnetic flowmeter, so that its functions are more diversified.

Description of drawings

Fig. 1 is a schematic diagram of a liquid flow test device of the present invention.

In the figure: 1. Built-in liquid tank, 2. Low-noise liquid pump, 3. Drain valve, 4. Stabilized liquid source, 5. Temperature transmitter 6. Electromagnetic switch valve 7. Pressure transmitter, 8. Clamping Device, 9. Pressure transmitter, 10. Tested meter, 11. Pressure transmitter, 12. Pressure transmitter, 13. High-precision automatic regulating valve, 14. Touch screen (with CPU inside), 15. Electromagnetic Flow meter, 16. Mode switching valve A, 17. Mode switching valve B, 18. Reverser, 19. Standard gauge, 20. Drain valve, 21. Electronic weighing device, 22. Temperature control water inlet valve, 23 ..Temperature-controlled drain valve, 24. Built-in electric control box (PLC inside), 25. Built-in toolbox.

specific implementation plan

The utility model is described in further detail below in conjunction with the accompanying drawings.

As shown in Figure 1, it is a schematic diagram of a liquid flow test device. A temperature transmitter 5 is installed on the upper part of the pressure-stabilizing liquid source 4, and a drain valve 3 is installed on the lower part. The liquid of the pressure-stabilizing liquid source 4 enters the test channel through the outlet, and the electromagnetic switch valve 6 and pressure transmitter are arranged in sequence on the test channel. 7, clamp 8, pressure transmitter 9, tested gauge 10, pressure transmitter 11, pressure transmitter 12, high-precision automatic regulating valve 13, electromagnetic flowmeter 15, and the set mode switching valve A16, commutator 18, standard measuring device 19, electronic weighing device 21, two standard measuring devices 19 are provided with a drain valve 20 at the bottom. During the test, the liquid in the pressure-stabilizing liquid source 4 passes through the above-mentioned device on the test channel. After the test is finished, it will flow out from the drain valve 20 to the built-in liquid tank 1, or directly into the built-in liquid tank 1 through the mode switching valve B17, and then pumped into the stable pressure liquid source 4 by the low-noise pump 2 for circulation, and the built-in liquid tank 1 will also contain There is a temperature-controlled water inlet valve 22 and a temperature-controlled water outlet valve 23 to replenish or discharge liquid.

The signal acquisition and control of the liquid flow in the test channel is realized by the PLC arranged in the built-in electric control box 24, and the data exchange and processing of the liquid flow in the test channel is realized by the CPU arranged in the touch screen 14, The touch screen 14 displays the results of data exchange and processing.

When the liquid flow test device detects the throttling piece at the tested meter position 10, the mode switching valve A16 is closed, and the mode switching valve B17 is opened. There are the following two test methods:

1. Preset the flow rate to measure the pressure loss. When the water flow is stable, according to the pre-set instantaneous flow Q, it is controlled and regulated by the high-precision automatic regulating valve, and the pressure at the front and rear ends of the tested meter 10 is dynamically and synchronously measured through the pressure transmitter 9 and the pressure transmitter 11. The difference P, that is, the pressure loss of the checked throttling piece, this value is _marked with the standard pressure loss P of the checked throttling piece at the flow point (according to the pressure loss in the throttling parameter table of the checked throttling piece Comparing with the corresponding relationship of the flow rate), the CPU calculates the relative error according to the formula ε=(PP _standard )/P _standard ×100%, and judges whether it is qualified, and the test result is automatically reported by the CPU.

2. Preset pressure loss to measure flow. When the water flow is stable, according to the pre-set pressure loss value P of the throttle part to be tested, it is controlled and regulated by the high-precision automatic regulating valve 13, and the instantaneous flow rate Q of the meter 10 to be tested is dynamically and synchronously measured by the electromagnetic flowmeter 15 , compare this value with _the standard flow Q standard of the checked throttling piece at the pressure loss point (according to the corresponding relationship between pressure loss and flow rate in the throttling parameter table of the checked throttling piece), by The CPU calculates the relative error according to the formula ε=(QQ _mark )/Q _mark ×100%, and judges whether it is qualified or not. The test result is automatically reported by the CPU.

When the electromagnetic flowmeter 15 on the device is to be calibrated or verified, the mode switching valve A is opened, the mode switching valve B is closed, the drain valve 20 is closed, and the electromagnetic flowmeter is calibrated by volume. Its advantage is that it can avoid the disassembly of the electromagnetic flowmeter, and it can be calibrated or verified at any time. This method can also be used to directly calibrate and detect the throttling parts to be checked.

The function of the electronic weighing device is to calibrate or verify the electromagnetic flowmeter 15 and the standard measuring device 19 more accurately. Compared with other methods, the mass method is easier to calibrate on site and has higher accuracy, so the traceability of the entire device is more convenient and accurate. This method can also be used to directly check the throttling parts for calibration testing.

A built-in tool box 25 is also provided in this test device.

It is beneficial that the meter position of the checked throttling part of the utility model is not only suitable for detecting throttling parts, but also very suitable for detecting water flow appliances, such as water meters, flow meters, etc., so that the detection functions are more diversified and the accuracy is high. Higher, better reliability.

Claims (5)

1. A liquid flow test device, the test channel of the test device is a sealed channel with a liquid flow inside, and the test channel is sequentially provided with a pressure-stabilizing liquid source (4), a temperature transmitter (5 ), electromagnetic switch valve (6), pressure transmitter (7), clamp (8), pressure transmitter (9), tested meter (10), pressure transmitter (11), pressure transmitter transmitter (12), high-precision automatic regulating valve (13), electromagnetic flowmeter (15), the signal acquisition and control of the liquid flow in the test channel is realized by the PLC installed in the built-in electric control box (24) , realize the data exchange and processing of the flow signal in the test channel by the CPU located in the touch screen (14), the touch screen (14) displays the results of data exchange and processing, and it is characterized in that: the test channel is also provided with Including the volumetric method test device that mode conversion valve A (16), commutator (18), standard gauge (19) are formed; A mass method test device composed of a device (19) and an electronic weighing device (21). 2. A liquid flow test device according to claim 1, characterized in that: a mode switching valve B (17) is arranged between the electromagnetic flowmeter (15) and the mode switching valve A (16). 3. A kind of liquid flow test device according to claim 1, characterized in that: the control of liquid flow in the volumetric test device and the mass method test device is realized by the PLC arranged in the built-in electric control box (24). Signal acquisition and control. 4. A liquid flow testing device according to claim 1 or 3, characterized in that: the liquid collected in the volumetric test device and the mass method test device is realized by the CPU arranged in the touch screen (14). Data exchange and processing of flow signals, the touch screen (14) displays the results of data exchange and processing. 5. A liquid flow test device according to claim 1, characterized in that: there are at least two standard gauges (19).

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