Method for screening and pairing zero-flow output characteristics of ultrasonic water meter timing chip

Abstract

The application discloses a kind of screening and pairing method of ultrasonic water meter timing chip zero-flow output characteristics, comprising the following steps: setting the zero-flow output value of the timing chip to be detected is divided into grade value;Zero-flow output measuring device of timing chip is set, and the zero-flow output measuring device of timing chip includes special measuring unit of timing chip and zero-flow measuring unit electrically connected with special measuring unit of timing chip, and the timing chip is electrically connected with special measuring unit of timing chip by chip clamping unit;Zero-flow output characteristic value of each measured timing chip is measured using the zero-flow output measuring device of timing chip, and the zero-flow output characteristic value is characterized by the axial line average flow velocity of fluid in pipeline;According to the measurement result, the zero-flow output value of the measured timing chip is divided into grade according to the setting grade value;Different grades of measured timing chip are used for different flow measurement range ultrasonic water meter.

Description

Technical Field

[0001] This invention belongs to the field of ultrasonic water meter technology, specifically relating to a method for screening and matching ultrasonic water meter timing chips with zero flow output characteristics. Background Technology

[0002] With the increasing demand for low-flow-rate measurements in water supply pipelines, the flow measurement range of ultrasonic water meters is also continuously expanding. Currently, the flow measurement range ratio of ultrasonic water meters is generally required to be at the R400 level, with some claiming to have reached R1000. For a nominal diameter of DN20 and Q3=4m... 3 For small-diameter ultrasonic water meters with a flow rate of / h and R1000, the minimum flow rate Q1 value has reached 4l / h.

[0003] One of the main factors limiting the extension of ultrasonic water meters to low flow rate measurement range is the zero-flow output characteristic of the timing chip. Currently, this indicator of various timing chips can only be controlled within ±0.5 mm / s (usually expressed as the flow rate output value when the measured flow velocity is zero). Summary of the Invention

[0004] In view of the above-mentioned problems, the present invention provides a method for screening and matching the zero flow output characteristics of ultrasonic water meter timing chips, which is used to measure and classify the zero flow output value, establish an evaluation and usage mechanism, and minimize the impact of zero flow output on the small flow measurement of ultrasonic water meters.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A method for screening and matching ultrasonic water meter timing chips with zero flow output characteristics includes the following steps:

[0007] Set the zero-flow output value of the timing chip under test in different ranges;

[0008] A zero-flow output measurement device for a timing chip is set up. The zero-flow output measurement device for the timing chip includes a dedicated measurement unit for the timing chip and a zero-flow measurement unit electrically connected to the dedicated measurement unit for the timing chip. The timing chip under test is electrically connected to the dedicated measurement unit for the timing chip through a chip clamping unit.

[0009] The zero-flow output characteristic value of each timing chip under test is measured using the zero-flow output measurement device of the timing chip, and the zero-flow output characteristic value is characterized by the axial average flow velocity of the fluid in the pipe.

[0010] Based on the measurement results, the zero-flow output value of the timing chip under test is divided into grades according to the set grade values;

[0011] Different grades of timing chips are used in ultrasonic water meters with different flow measurement ranges.

[0012] In one possible implementation, the zero flow measurement unit includes a transceiver A and a corresponding transceiver B installed inside the pipe. The distance between the end faces of the transceiver A and the corresponding transceiver B is L. The transceiver A and the transceiver B are electrically connected to a dedicated measurement unit for the timing chip.

[0013] In one possible implementation, measuring the zero-flow output characteristic value of each timing chip under test using the zero-flow output measurement device of the timing chip includes:

[0014] The timing chip under test is mounted on a dedicated measurement unit for timing chips;

[0015] To ensure that the timing zero flow measurement unit meets the conditions including still water, no vibration, and constant temperature;

[0016] Start measuring the forward and reverse ultrasonic transit times of the measured timing chip, calculate the time difference between the forward and reverse ultrasonic transit times, and obtain the axial average velocity of the fluid in the pipe.

[0017] The time difference of the measured timing chip was measured and calculated multiple times to obtain the average value and experimental standard deviation of the axial linear average velocity of the fluid in the pipe.

[0018] Display the measurement results.

[0019] In one possible implementation, the forward and reverse transit times of the ultrasonic waves are measured by the timing chip under test. The time difference between the forward and reverse transit times is calculated to obtain the axial average velocity of the fluid in the pipe.

[0020] Forward transit time of ultrasound

[0021] Ultrasonic reverse transit time

[0022] Time difference

[0023] Then obtained

[0024] in The axial average velocity of the fluid inside the pipe; ω is the angle between the central axis of a pair of ultrasonic transducers and the axis of the measuring tube; c is the speed of ultrasonic wave propagation in water; D is the inner diameter of the ultrasonic water meter measuring tube.

[0025] One possible implementation involves setting graded values ​​for the zero-flow output value of the timing chip under test, including:

[0026] A-level: ≤±0.1mm / s

[0027] B-level: ≤±0.3mm / s; >±0.1mm / s

[0028] C-range: ≤±0.5mm / s; >±0.3mm / s

[0029] D mode: > ±0.5mm / s.

[0030] One possible implementation of an ultrasonic water meter that uses different grades of timing chips for different flow measurement ranges includes:

[0031] Use the timing chip in the A-grade range for ultrasonic water meters with an R400 or higher rating.

[0032] Use the timing chip in the B range for ultrasonic water meters with R250 and R400 or lower.

[0033] Use the timing chip in the C range for ultrasonic water meters with R160 and R250 or lower.

[0034] Eliminate the timing chip being tested in the D mode.

[0035] The present invention has the following beneficial effects: by screening and matching the zero flow output characteristics of batch timing chips, the zero flow output value is measured and classified, and an evaluation and usage mechanism is established to minimize the impact of zero flow output on the small flow measurement of ultrasonic water meters. That is, timing chips with small zero flow output values ​​are used in ultrasonic water meters with a wide flow measurement range, and timing chips with large zero flow output values ​​are used in ultrasonic water meters with a narrow flow measurement range. At the same time, timing chips with zero flow output values ​​exceeding the specified requirements are eliminated. Attached Figure Description

[0036] Figure 1 This is a flowchart illustrating the steps of the screening and pairing method for the zero-flow output characteristics of ultrasonic water meter timing chips according to an embodiment of the present invention.

[0037] Figure 2 This is a schematic diagram of the structure of the dedicated measuring device for zero-flow output of the timing chip in an embodiment of the present invention;

[0038] Figure 3 This is a schematic diagram of the installation of the ultrasonic water meter transducer in an embodiment of the present invention. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. 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.

[0040] Reference Figure 1 The diagram shows a flowchart of the screening and matching method for the zero-flow output characteristic of an ultrasonic water meter timing chip according to an embodiment of the present invention, including the following steps:

[0041] S10, Set the zero flow output value of the timing chip under test in different ranges;

[0042] S20, setting up a zero-flow output measurement device for the timing chip, see [link / reference] Figure 2 The zero-flow output measurement device for timing chips includes a dedicated measurement unit for timing chips and a zero-flow measurement unit electrically connected to the dedicated measurement unit for timing chips. The timing chip under test is electrically connected to the dedicated measurement unit for timing chips through a chip clamping unit.

[0043] S30, the zero flow output measurement device of the timing chip is used to measure the zero flow output characteristic value of each timing chip under test, and the axial average flow velocity of the fluid in the pipe is used to characterize the zero flow output characteristic value.

[0044] S40, based on the measurement results, classify the zero flow output value of the timing chip under test according to the set classification value;

[0045] The S50 uses different grades of timing chips for ultrasonic water meters with different flow measurement ranges.

[0046] See also Figure 2In one embodiment of the present invention, the zero-flow measurement unit includes a transceiver A and a corresponding transceiver B installed inside the pipe. The distance between the end faces of transceiver A and the corresponding transceiver B is L. Transceiver A and transceiver B are electrically connected to a dedicated measurement unit for a timing chip. L should be sufficiently long, typically between 150 and 200 mm, to ensure a sufficiently large time difference value, thereby improving the resolution of the measured time difference. The zero-flow measurement unit can be made of metal materials (such as stainless steel, brass, etc.); it is required that the zero-flow measurement unit has sufficient mechanical strength (it will not undergo significant mechanical deformation that would cause creep of the distance L); the pipe is filled with drinking water and the distance L between the working surfaces of the two transducers (A and B) remains constant (a limiting structure is required to ensure this); the two transducers (A and B) are installed at both ends of the zero-flow measurement unit; during use, the zero-flow measurement unit is placed on a sturdy working platform to prevent it from being affected by any vibration (i.e., the drinking water in the zero-flow measurement unit is kept completely still), and the zero-flow measurement unit is kept at a basically constant temperature (e.g., 20±1℃; this needs to be ensured by an external temperature control device). Only the above conditions can meet the requirements for screening (measuring) the timing chip being measured.

[0047] In one embodiment of the present invention, S30, measuring the zero-flow output characteristic value of each timer chip under test using the zero-flow output measuring device of the timer chip includes:

[0048] S301, the timing chip under test is clamped onto the dedicated measurement unit for timing chips;

[0049] S302 ensures that the timing zero flow measurement unit meets the conditions including still water, no vibration, and constant temperature.

[0050] S303, start measuring the forward and reverse transit times of the ultrasonic waves of the timing chip under test, calculate the time difference between the forward and reverse transit times of the ultrasonic waves, and obtain the axial average velocity of the fluid in the pipe.

[0051] S304, by repeatedly measuring and calculating the time difference of the measured timing chip, the average value and experimental standard deviation of the axial linear average velocity of the fluid in the pipe are obtained.

[0052] S304 displays the measurement results.

[0053] The zero-flow output value of a single timing chip is usually confirmed by the average value (x) of multiple measurements as the basis for evaluation (screening and grading); at the same time, dispersion (i.e. experimental standard deviation σ) should be used as an auxiliary reference indicator (e.g., for timing chips with a small average value, if the standard deviation is large, they usually cannot be selected or should be used at a lower grade).

[0054] Further, in step S303, the measurement of the ultrasonic forward transit time and ultrasonic reverse transit time of the timing chip under test is initiated. The time difference between the ultrasonic forward transit time and ultrasonic reverse transit time is calculated to obtain the axial average velocity of the fluid in the pipe. (See [reference needed]). Figure 3 This is a schematic diagram showing the installation of transceiver A and transceiver B.

[0055] Forward transit time of ultrasound

[0056] Ultrasonic reverse transit time

[0057] Time difference

[0058] Then obtained

[0059] in The axial average velocity of the fluid inside the pipe; denoted as , where is the angle between the central axis of a pair of ultrasonic transducers and the axis of the measuring tube; c is the speed of ultrasonic wave propagation in water; and D is the inner diameter of the ultrasonic water meter measuring tube.

[0060] During measurement, the water medium in the zero flow measurement unit must be strictly still, free of bubbles, and free from external vibrations. The water temperature change in the medium needs to be kept constant within a small range (e.g., ±1℃).

[0061] In one embodiment of the present invention, S10, setting the zero-flow output value of the timing chip under test in tiers includes:

[0062] A-level: ≤±0.1mm / s

[0063] B-level: ≤±0.3mm / s; >±0.1mm / s

[0064] C-range: ≤±0.5mm / s; >±0.3mm / s

[0065] D mode: > ±0.5mm / s.

[0066] The specific grading values ​​above are just application examples and can be changed according to the actual situation.

[0067] Based on the specific grading settings above, different grades of the timing chip under test can be used in ultrasonic water meters with different flow measurement ranges, including:

[0068] Use the timing chip in the A-grade range for ultrasonic water meters with an R400 or higher rating.

[0069] Use the timing chip in the B range for ultrasonic water meters with R250 and R400 or lower.

[0070] Use the timing chip in the C range for ultrasonic water meters with R160 and R250 or lower.

[0071] Eliminate the timing chip being tested in the D mode.

[0072] The above describes the use of different grade timing chips in ultrasonic water meters with different flow measurement ranges, which can be changed according to the actual situation.

[0073] By using the above screening and matching method based on the zero flow output characteristics of ultrasonic water meter timing chips, timing chips with small zero flow output values ​​can be used in ultrasonic water meters with a wide flow measurement range, while timing chips with large zero flow output values ​​can be used in ultrasonic water meters with a narrow flow measurement range. At the same time, timing chips with zero flow output values ​​exceeding the specified requirements are eliminated.

[0074] It should be understood that the exemplary embodiments described herein are illustrative and not restrictive. Although one or more embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art will understand that various changes in form and detail may be made without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A method for screening and matching ultrasonic water meter timing chips with zero flow output characteristics, characterized in that, Includes the following steps: Set the zero-flow output value of the timing chip under test in different ranges; A zero-flow output measurement device for a timing chip is set up. The zero-flow output measurement device for the timing chip includes a dedicated measurement unit for the timing chip and a zero-flow measurement unit electrically connected to the dedicated measurement unit for the timing chip. The timing chip under test is electrically connected to the dedicated measurement unit for the timing chip through a chip clamping unit. The zero-flow output characteristic value of each timing chip under test is measured using the zero-flow output measurement device of the timing chip, and the zero-flow output characteristic value is characterized by the axial average flow velocity of the fluid in the pipe. Based on the measurement results, the zero-flow output value of the timing chip under test is divided into different ranges according to the set range values; Using different grades of timing chips for ultrasonic water meters with different flow measurement ranges; The measurement of the zero-flow output characteristic value of each timing chip under test using the zero-flow output measurement device of the timing chip includes: The timing chip under test is mounted on a dedicated measurement unit for timing chips; To ensure that the timing zero flow measurement unit meets the conditions including still water, no vibration, and constant temperature; Start measuring the forward and reverse ultrasonic transit times of the measured timing chip, calculate the time difference between the forward and reverse ultrasonic transit times, and obtain the axial average velocity of the fluid in the pipe. The time difference of the measured timing chip was measured and calculated multiple times to obtain the average value and experimental standard deviation of the axial linear average velocity of the fluid in the pipe. Display measurement results; Setting graded values ​​for the zero-flow output of the timing chip under test includes: A-level: ≤± 0.1mm / s; B-level: ≤± 0.3mm / s; >± 0.1mm / s; C-range: ≤± 0.5mm / s; >± 0.3mm / s; D mode: > ± 0.5mm / s; Ultrasonic water meters that use different grades of timing chips for different flow measurement ranges include: Use the timing chip in the A-grade range for ultrasonic water meters with an R400 or higher rating; Use the timing chip in the B range for ultrasonic water meters with R250 and R400 or lower. Use the timing chip in the C range for ultrasonic water meters with R160 and R250 or lower. Eliminate the timing chip being tested in the D mode.

2. The screening and matching method for the zero-flow output characteristic of ultrasonic water meter timing chips as described in claim 1, characterized in that, The zero flow measurement unit includes a transceiver A and a corresponding transceiver B installed inside the pipe. The distance between the end faces of the transceiver A and the corresponding transceiver B is L. The transceiver A and the transceiver B are electrically connected to the dedicated measurement unit of the timing chip.

3. The screening and matching method for the zero-flow output characteristic of ultrasonic water meter timing chips as described in claim 1, characterized in that, The measurement of the ultrasonic forward transit time and ultrasonic reverse transit time of the timing chip under test is initiated. The time difference between the ultrasonic forward transit time and ultrasonic reverse transit time is calculated to obtain the axial average velocity of the fluid in the pipe. Forward transit time of ultrasound (2) Ultrasonic reverse transit time (3) Time difference (4) Then obtained (5) in The axial average velocity of the fluid inside the pipe; The angle between the central axis of a pair of ultrasonic transducers and the axis of the measuring tube; The speed at which ultrasound travels in water; The inner diameter of the measuring tube in an ultrasonic water meter.

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