RU2616711C1 - Method and device for accelerated verification (calibration) of flow meter (meter) - Google Patents

Abstract

FIELD: measuring equipment.

SUBSTANCE: distinctive solution feature is that the detectors of the initial and final positions of the piston-displacer are provided with contact groups to issue multiple signals of each detector activation, and the secondary device is equipped with the appropriate number of additional measurement channels to accumulate and mathematically process the pulse sequences of the flow transducer, limited in time by the activation moments of the contact detector groups for the initial and final positions of the piston-displacer, wherein the total number of detectors for the initial and final positions of the piston-displacer is not more than four. The method of accelerated verification (calibration) of a flow meter, a volume meter, a mass meter is implemented by this device, the distinctive feature of which is that the measurement of the pulse number is made, time-limited by the activation moments of the contact detector groups for the initial and final positions of the piston-displacer, as it passes from the initial to the final position in the calibrated plot and from the final to the initial position therein, a series of the calibrated plot volume values is calculated, limited by the activation moments of the contact detector groups for the initial and final positions of the piston-displacer. The total number of detectors for the initial and final positions of the piston-displacer is not more than four, the conversion rate of the varified (calibrated) flow meter, volume meter, mass meter is determined by assigning the number of pulses accumulated in the secondary device from the flow meter, volume meter, mass meter to the corresponding amount of the calibrated plot volumes of the said device.

EFFECT: reducing the operating time of the device in the measurement process, and improving the accuracy of the measurement results.

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Description

1. The technical field to which the invention relates.

The invention relates to the subsection of metrology - flow measurement (according to the international classification G01F), and can be used for verification (calibration) of flow meters, volume and mass meters.

2. The prior art.

A device is known - a tube-piston calibration unit (hereinafter TPU) and a foreign analog of TPU - a prover (prover, meter prover) for checking and calibrating a flowmeter technologically associated with it. The properties of TPU and the method for checking flow converters using TPU are given in MI 3380-2012 “Recommendation. State system for ensuring the uniformity of measurements. Volume flow converters. Verification Technique. ” (Approved on September 10, 2012 by the All-Russian Scientific Research Institute of Flow Metering, Kazan).

TPU, or prover (see Fig. 1), contains a calibrated section of the pipeline (pos. 1), a piston-displacer (pos. 2) moving in the calibrated section under the influence of the flow of the measured medium (in Fig. 1, the flow direction is arbitrarily shown by the arrow ), switch of the flow direction of the measured medium in TPU (pos. 5), single-signal detectors of the initial (pos. 6, 7) and end (pos. 8, 9) positions of the displacer piston in the calibrated section of the TPU pipeline (or prover), a secondary device (item 3), carrying out the accumulation and mathematical processing of measuring th information from the flowmeter (pos. 4) in the form of pulse sequences of time-instants detectors of the initial and final positions of the displacer piston-TPU in a calibrated portion, and the detector is equipped with contacts for the issuance of one of its actuation signal. TPU uses two detectors of the extreme positions of the displacer piston, but TPU can also be equipped with four detectors, two of which are redundant. The initial and final positions of the displacing piston are conventionally designated, since the next switching of the flow of the measured medium causes the displacing piston to move in the opposite direction, therefore the detectors that have worked out the signal for the end of the first passage of the displacing piston through the calibrated section of the pipeline, which is called a half-cycle, become the detectors of the beginning of the next half cycle. Thus, the TPU duty cycle consists of two consecutive half-cycles in the forward and reverse directions.

The disadvantage of TPU (prover) is the need for multiple passage of the displacer piston in a calibrated section to accumulate a sufficient number of pulse sequences from the flow meter for their statistical analysis and reject invalid measurement results, which leads to significant time and energy costs for calibration or verification of a single flow transducer. The time-consuming procedure of multiple measurements is accompanied by a change in ambient temperature and the measured medium, pressure in the pipeline, a change in the mixing conditions of the flows of the measured heterogeneous medium, which leads to an increase in the error of the measurement result. In addition, under conditions of an unstable or smoothly changing flow rate over time, the use of TPU (prover) without taking special measures to maintain the selected flow rate becomes impossible.

Processing of measurement information with the known method of verification (calibration) of the flowmeter reduces to the accumulation of a sufficient number of pulse sequences during repeated passage of the displacer piston from the initial position to the final and vice versa to calculate the average value of the conversion coefficient as the ratio of the number of pulses of the flow meter averaged over a certain number of operating cycles, to the known volume of the calibrated TPU section (prover).

3. The invention

The aim of the invention is the multiple reduction of the operating time of the TPU (prover) during calibration (calibration) of the flow meter and improving the accuracy of measurements by eliminating the influence of destabilizing factors that smoothly change over time.

The goal is achieved by the fact that in the device for checking (calibrating) the flow meter, volumetric meter, mass meter containing a calibrated section of the pipeline, a displacer piston moving in a calibrated section under the influence of the measured medium flow, detectors of the initial and final positions of the displacer piston in a calibrated section pipeline, a secondary device that performs the accumulation and mathematical processing of measurement information received from the flow meter in the form of pulse sequences limited to about the time of the response times of the detectors of the initial and final positions of the piston-displacer in the calibrated section of the pipeline, the detectors of the initial and final positions of the piston-displacer are equipped with contact groups for issuing a set of signals about the operation of each detector, in addition, the secondary device is equipped with additional measuring channels for accumulation and mathematical processing a plurality of pulse sequences from a flow meter, time limited by the response times of contact groups the initial and final position of the displacer piston during its movement in the calibrated section of the pipeline, while the total number of detectors of the initial and final position of the displacer piston is not more than four.

Since a plurality of signals from contact groups generates a plurality of pulse sequences from a flowmeter, this ultimately allows you to quickly obtain the required amount of measurement information, sufficient for mathematical processing and verification of the metrological characteristics of the flowmeter at the selected flow rate of the measured medium, which also allows to obtain high measurement accuracy by reducing the influence of time-varying calibration (calibration) conditions.

4. The list of figures of drawings (diagrams, drawings, applications)

1. FIG. 1. A diagram explaining the verification process (calibration) of the flow meter using the well-known TPU (prover).

2. FIG. 2. Figure illustrating the possibility of receiving several signals about the detector operation by switching on several reed switches (pos. 2), controlled by one magnetic part of the detector (pos. 1).

3. FIG. 3. A diagram explaining the process of calibration (calibration) of the flowmeter using the claimed TPU (many signals about the operation of each detector are conventionally indicated by two communication lines).

4. Appendix 1, explaining the principle of operation of the prover according to US patent No. 3021703.

5. Appendix 2, explaining the principle of operation of the "compact prover" according to US patent No. 4549426.

6. Appendix 3, explaining the principle of the detector according to US patent No. 5263220.

5. Information confirming the possibility of carrying out the invention

Appendix 1 explains the principle of operation of the prover in accordance with US patent No. 3021703 [1], where pos. 11 - flow meter, pos. 13, 15, 17 - electronic devices necessary for counting pulses from the flow meter, pos. 19, 21 - flow switches of the measured medium, pos. 22 - calibrated pipe prover, pos. 23 - piston-displacer, pos. 30. 31 - limit switches (single-signal detectors).

Appendix 2 explains the principle of operation of the "compact prover" in accordance with US patent No. 4549426 [2], where pos. 24, 25 - single-signal detectors made on the basis of sealed magnetically controlled contacts - reed switches, which are triggered by the action of a magnetic initiator pos. 21, mounted on the rod pos. 19 connected to a displacing piston performing measuring cycles in a calibrated compact prover pipe; pos. 56, a controller is designated as a secondary device for counting pulses from a flow meter and calculating a conversion coefficient.

Appendix 3 explains the operating principle of the limit switch used in the prover (see Appendix 1) in accordance with US patent No. 5263220 [3] (single-signal detector), which has a normally open reed switch contact (key 61), closed at the time of extrusion by the displacer piston (as it moves) the detector rod (key 25) to the appropriate position to control, using the magnetic part (key 60), the contact state of the reed switch.

In FIG. Fig. 2 is a drawing explaining the possibility of obtaining several signals about the operation of the detector by switching on several reed switches controlled by one magnetic part.

As the detectors of the initial (final) position of the piston-displacer in the claimed TPU, a detector is used with the replacement of one normally open contact with a contact group, which, when the detector is triggered, independently closes a series of (more than one) normally open contacts, which, accordingly, allows you to replace several detectors with said contact group detector.

When equipping the devices shown in the figures of Appendix 1 and Appendix 2 with detectors of the initial and final positions of the displacer piston with contact groups, it is possible to implement the claimed TPU, schematically shown in FIG. 3, where:

1 - calibrated section of the pipeline;

2 - piston-displacer;

3 - secondary device;

4 - flowmeter, volumetric meter or mass meter;

5 - switch the direction of flow of the measured medium in TPU;

6, 7, 8, 9 — position detectors of the displacer piston with contact groups.

As shown in FIG. 3, the secondary device (pos. 3) is connected to a calibrated (calibrated) flowmeter (pos. 4) and detectors of the piston-propellant, from which the detectors of the initial position of the piston-propellant - pos. 6, 7 and end position detectors - pos. 9, 10.

The pulses from the flow meter continuously arriving at the secondary device are taken into account by the secondary device as a sequence of pulses limited by the moments of operation of the detectors. For example, with one pass of the displacer piston in the calibrated section of the pipeline from the initial to the final position and the operation of the secondary device with detectors No. 6, 7, 8, 9, equipped with contact groups with the symbol “a” and “b”, the measurement information consists from the pulse sequences below:

N _6a-8a , N _6a-9a , N _6b-8c , N _6b-9b , N _7a-8a , N _7a . _9a , N _7v-8v , N _7v-9v , N _6a-8v , N _6a-9v , N _6v-8a , N _6v-9a , N _7a-8v , N _{7a- 9v} , N _{7v -8a} , N _{7v- 9a}

Indexes 6a, 6b, 6c, 7a, 7c, 8a, 8c, 9a, 9c are conventionally marked pulse sequences initiated by the corresponding contact groups.

Each pulse sequence corresponds to a certain volume of the displaced measured medium when the piston-displacer moves along the calibrated section of the pipeline, limited by the response times of the respective detectors equipped with contact groups.

The total number of contact groups should be such that pulse sequences proportional to certain volumes, in total, provide a reliable result of determining the conversion coefficient of the calibrated (calibrated) flow meter in accordance with the claimed method of accelerated calibration (calibration) of the flow meter, in which using additional measuring channels of the secondary device TPU under the control of the corresponding software calculate the conversion coefficient of the flow as the ratio of the sum of a sufficient number of pulses of the pulse sequences of the secondary device for the formation of pulse sequences) to the sum of the corresponding volumes of the displaced measured medium, limited by the moments of operation of the respective detectors for the period of time the piston-displacer passes through the calibrated section of the pipeline from the initial to the final position or in one cycle ( movement of the displacer piston in the forward and reverse directions).

Information sources

1. US patent No. 3021703.

2. US patent No. 4549426.

3. US Patent No. 5263220.

Claims (5)

1. A device for checking (calibrating) a flowmeter, volumetric meter, mass meter, containing a calibrated section of the pipeline, a displacer piston moving in a calibrated section under the influence of the medium flow, detectors of the initial and final positions of the displacer piston in a calibrated pipeline section, containing contacts for the issuance of one signal about the operation of the detector, a secondary device that performs the accumulation and mathematical processing of measurement information from the calibrator (calib a flow meter, a volume meter, a mass meter in the form of pulse sequences limited in time by the response times of the detectors of the initial and final positions of the displacer piston in the calibrated section of the pipeline, characterized in that the detectors of the initial and final positions of the displacer piston during its movement in the calibrated section pipelines are equipped with contact groups, which, when the detector is triggered, allows to close the group of normally open contacts, and the secondary device is equipped with additionally measuring channels for accumulation and mathematical treatment of the transducer pulse sequences consumption, time-limited activation instants of contact groups detectors start and end positions of the piston-displacer, the total number of detectors of the initial and final positions of the displacer-piston is not more than four. 2. A device for checking (calibrating) a flowmeter, volumetric meter, mass meter according to claim 1, characterized in that the detectors of the initial and final positions of the piston-displacer are equipped with contact groups, which, when the detector is triggered, open a group of normally closed contacts. 3. A device for checking (calibrating) a flowmeter, volumetric meter, mass meter according to claim 1, characterized in that the detectors of the initial and final positions of the displacer piston are equipped with contact groups, which, when the detector is triggered, open a group of normally closed contacts and close a group of normally open contacts. 4. The device according to paragraphs. 1-3, characterized in that the detectors of the initial and final positions of the piston-displacer are equipped with a radio transmitting device, which transmits to the receiver of the secondary device that performs the necessary processing of the measurement information, the corresponding information about the moments of operation of the detectors. 5. A method for accelerated verification (calibration) of a flowmeter, volumetric meter, mass meter, including calculating the conversion coefficient of a calibrated (calibrated) flowmeter, volumetric meter, mass meter, characterized in that as a total result of measuring the number of pulses limited in time by the contact response times groups of detectors of the initial and final positions of the displacer piston during its passage in the calibrated section from the initial to the final position and from the final the initial position, apply the sum of a number of values of the pulse sequences from the calibrated (calibrated) flow meter, volumetric meter, mass meter with the corresponding total volume of the calibrated section being limited in time to the response times of the detectors of the initial and final positions of the displacer piston, and the device according to . 1-4.

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