CN-121994332-A - Online meter calibrating method based on instantaneous flow method, application and ultrasonic water meter calibrating table

CN121994332ACN 121994332 ACN121994332 ACN 121994332ACN-121994332-A

Abstract

The invention relates to the technical field of ultrasonic water meters, in particular to an online meter calibrating method based on an instantaneous flow method, which abandons the traditional method of relying on a high-precision electronic scale as a standard device, realizes full-automatic calibration of an ultrasonic water meter by adopting the instantaneous flow method, and simultaneously solves the problems that the ultrasonic water meter generally depends on a start-stop method or a reversing method, is difficult to be compatible with the instantaneous flow method and can realize accurate calibration only by custom transformation in the prior art, and does not need to re-customize a calibration platform specially adapted to the instantaneous flow method. The instantaneous flow method is successfully integrated on the traditional meter calibration table, the technical limitation of the existing equipment is overcome, the full-flow automation from measurement to judgment is realized, and the meter calibration efficiency is remarkably improved. Meanwhile, the method has the core requirement of flow output stability, and the harsh requirements on the control time sequence and the data reading synchronism of the calibration table are greatly reduced. Meanwhile, the application of the method in the actual meter calibrating process and an ultrasonic water meter calibrating table are also provided.

Inventors

LI SHIBO
YU XUEJUAN
WANG GUOTAO
WANG DA
WANG HANLEI
FAN XIAOLEI
GAO YANG
ZHENG JIE
FENG SHIPING

Assignees

青岛乾程科技股份有限公司

Dates

Publication Date: 20260508
Application Date: 20260330

Claims (10)

1. An online meter calibrating method based on an instantaneous flow method is characterized by comprising the following steps of: Step S1, determining flow operating points to be calibrated and temperature points to be measured, wherein the flow operating points at least comprise Q1, Q2, Q3 and Q4 flow points, and the temperature points are obtained by dividing according to preset temperature interval values; s2, selecting a temperature point and a flow operating point to be measured, receiving a temperature regulation instruction, regulating the temperature of water to be detected in the heat preservation water tank to a preset temperature, and keeping a constant temperature state; Step S3, setting fixed output flow for the meter calibration table and judging the stability of the output flow, if the output flow enters a stable state, entering the next step, otherwise, exiting the calibration process, and prompting the meter calibration table to be faulty; s4, after determining that the output flow enters a stable state, acquiring data of a standard meter and a water meter to be calibrated in a preset acquisition time, and calculating to obtain a meter coefficient; s5, selecting a next flow working point, and repeating the steps to obtain instrument coefficients of different flow working points corresponding to the temperature point; And S6, after the calculation of the instrument coefficients of all the flow operating points at the specific temperature point is completed, selecting the next temperature point, repeating the steps to obtain the instrument coefficients of all the corresponding flow operating points at different temperature points, forming a data network related to the temperature and the flow operating points, and completing the meter calibrating process.
2. The online meter calibrating method based on the instantaneous flow method according to claim 1, wherein the number of the flow operating points is gradually reduced from small to large according to the flow of the flow points Q1 to Q4.
3. The online meter calibrating method based on the instantaneous flow method according to claim 1, wherein the judging method of the stability of the output flow comprises the following steps: according to the preset sampling frequency, acquiring the instantaneous flow of the standard table in a preset time period; Combining the data of the obtained standard table to obtain a standard data set; taking a standard average value of the data in the obtained standard data set; Calculating the mean change rate of a plurality of groups of continuously adjacent standard data sets according to the standard mean value of the standard data sets; If the average value change rate is smaller than the preset change threshold value, judging that the output flow enters a stable state, otherwise, continuing to wait for the preset stable time; And if the preset stable time is exceeded and the stable state is not entered, exiting the meter correcting process to prompt the fault of the meter correcting table.
4. The online meter calibrating method based on the instantaneous flow method according to claim 3, wherein the calculating process of the mean change rate is as follows: Screening and removing two maximum values and two minimum values from data in a standard data set, and then calculating to obtain an average value; The average of the sets of standard data is selected, with the mean change rate = max average-min average.
5. The online meter calibrating method based on the instantaneous flow method according to claim 3, wherein the preset time period is more than or equal to 30s, the sampling frequency is more than or equal to 8 times, the preset change threshold is 1% of the acquired flow value, and the preset stabilization time is 3min.
6. The online meter calibrating method based on the instantaneous flow method according to claim 1, wherein the calculation process of the meter coefficient is as follows: Acquiring corresponding data sets of a standard meter and a water meter to be calibrated in a preset acquisition time, and calculating to obtain a standard average value and a to-be-calibrated average value; The calculation formula of the instrument coefficient is that the instrument coefficient=standard average value/average value to be calibrated.
7. Use of the instantaneous flow method-based on-line meter calibration method according to any one of claims 1 to 6 in an ultrasonic meter calibration stand, characterized in that the meter coefficient calculation method comprises the steps of assuming that the meter coefficient at the measurement point (T 0 ,Q 0 ) needs to be calculated 0 Wherein T is a temperature parameter, and Q is a flow parameter; The method comprises the steps of finding a data grid corresponding to the measuring point in a data network, wherein the flow operating point in the data grid is that the instrument coefficient corresponding to an operating point 1 (T 1 ,Q 1 ) is K 11 , the instrument coefficient corresponding to an operating point 2 (T 1 ,Q 2 ) is K 12 , the instrument coefficient corresponding to an operating point 3 (T 2 ,Q 1 ) is K 21 , and the instrument coefficient corresponding to an operating point 4 (T 2 ,Q 2 ) is K 22 , wherein T 1 ≤T 0 ≤T 2 ,Q 1 ≤Q 0 ≤Q 2 ; Calculating by adopting a bilinear interpolation method, wherein the specific process is as follows: At the flow Q 1 and the flow Q 2 , the temperature T 0 is used for interpolation, and the calculation formula is that ：K(T 0 ,Q 1 )=K 11 +(K 21 -K 11 )*(T 0 -T 1 )/(T 2 -T 1 ),K(T 0 ,Q 2 )=K 12 +(K 22 -K 12 )*(T 0 -T 1 )/(T 2 -T 1 ); Then interpolating in the flow direction, and obtaining an instrument coefficient K 0 of the measuring point by using Q 0 interpolation; K 0 =K(T 0 ,Q 1 )+（K(T 0 ,Q 2 )-K(T 0 ,Q 1 )）*(Q 0 -Q 1 )/(Q 2 -Q 1 ).
8. The use of the on-line meter calibrating method based on the instantaneous flow method according to claim 7 in an ultrasonic meter calibrating table, wherein the instantaneous flow in the pipe section is calculated according to the meter coefficient finally obtained by the meter calibrating The calculation formula is as follows: wherein, the method comprises the steps of, The current propagation speed of the ultrasonic pulse in the water; measuring the inner diameter of a pipe section for an ultrasonic water meter; Measuring time difference for uplink and downlink propagation of ultrasonic pulses; Is the instrument coefficient.
9. The utility model provides an ultrasonic water meter school table, its characterized in that includes flow output device, user control platform, school table host computer, network switch and serial ports server, flow output device is used for controlling stable flow output, user control platform is connected with the calibration table host computer, wait to calibrate the water gauge signal respectively through the network switch, the network switch is connected with a plurality of wait to calibrate the water gauge and the inside standard table signal of school table through serial ports server.
10. An ultrasonic water meter calibration stand according to claim 9, wherein the standard meter is provided as an electromagnetic flow meter.

Description

Online meter calibrating method based on instantaneous flow method, application and ultrasonic water meter calibrating table Technical Field The invention relates to the technical field of ultrasonic water meters, in particular to an online meter calibrating method based on an instantaneous flow method, application and an ultrasonic water meter calibrating table. Background The traditional ultrasonic water meter calibration table generally uses a start-stop method or a reversing method, the start-stop method needs to frequently start and cut off water flow, the verification process is intermittent, the efficiency is low, flow state disturbance and timing errors can be introduced into the valve start-stop action, and the real performance of the water meter under continuous and stable flow is difficult to reflect. The reversing law relies on a set of precision fluid reversing devices to achieve cumulative metering by alternately introducing water flow into a standard vessel, which, while avoiding shut-off, is complex, costly, and also suffers from flow fluctuations and uncertainty due to reversing mechanism action. Therefore, the two methods are generally more suitable for high-precision calibration in a laboratory, and under the production site or site calibration scene requiring quick, on-line and continuous verification, the instantaneous flow method has the remarkable advantages of high efficiency, convenience and more approaching to the actual use working condition because of direct comparison of instantaneous values in continuous stable flow, and can remarkably improve the calibration efficiency. The instantaneous flow method obtains an instantaneous error curve by collecting all instantaneous flow points of the detected meter and the corresponding standard meter, and can automatically correct the metering coefficient in the water meter by infrared communication and other modes to finish calibration. The ultrasonic water meter calibration table which is delivered at present mostly supports the operation of a start-stop method or a reversing method, but the instantaneous flow method is often not supported and compatible, so that the calibration table is required to be redesigned according to the instantaneous flow method based on the prior art, the standard table is required to have higher precision, the instantaneous flow of the checked table and the standard table can be synchronously read, and the requirements are easier to realize in the specially designed calibration table by using the standard table or the output of a piston as a flow standard. However, in old meter calibrating tables purchased before a water meter producer, the synchronicity of information reading is difficult to realize, so that the flow passing through the pipeline is required to be in a stable flow state, and the flow state is verified, so that the accuracy of calibration is improved. Disclosure of Invention The invention aims to provide an on-line meter calibrating method based on an instantaneous flow method and an ultrasonic water meter calibrating table, so as to solve the problems in the prior art. In order to solve the technical problems, the technical scheme provided by the invention is that an online meter calibrating method based on an instantaneous flow method is provided, and the method comprises the following steps: Step S1, determining flow operating points to be calibrated and temperature points to be measured, wherein the flow operating points at least comprise Q1, Q2, Q3 and Q4 flow points, and the temperature points are obtained by dividing according to preset temperature interval values; s2, selecting a temperature point and a flow operating point to be measured, receiving a temperature regulation instruction, regulating the temperature of water to be detected in the heat preservation water tank to a preset temperature, and keeping a constant temperature state; Step S3, setting fixed output flow for the meter calibration table and judging the stability of the output flow, if the output flow enters a stable state, entering the next step, otherwise, exiting the calibration process, and prompting the meter calibration table to be faulty; s4, after determining that the output flow enters a stable state, acquiring data of a standard meter and a water meter to be calibrated in a preset acquisition time, and calculating to obtain a meter coefficient; s5, selecting a next flow working point, and repeating the steps to obtain instrument coefficients of different flow working points corresponding to the temperature point; And S6, after the calculation of the instrument coefficients of all the flow operating points at the specific temperature point is completed, selecting the next temperature point, repeating the steps to obtain the instrument coefficients of all the corresponding flow operating points at different temperature points, forming a data network related to the temperature and the flow operating points, and co