CN113739877A - Ultrasonic method online calibration device and method for liquid flowmeter - Google Patents

Ultrasonic method online calibration device and method for liquid flowmeter Download PDF

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Publication number
CN113739877A
CN113739877A CN202111041926.1A CN202111041926A CN113739877A CN 113739877 A CN113739877 A CN 113739877A CN 202111041926 A CN202111041926 A CN 202111041926A CN 113739877 A CN113739877 A CN 113739877A
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CN
China
Prior art keywords
ultrasonic
frame
locking
liquid flowmeter
flowmeter
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Pending
Application number
CN202111041926.1A
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Chinese (zh)
Inventor
肖红军
于航
白雪峰
刘猛
张晓晗
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AECC Shenyang Liming Aero Engine Co Ltd
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AECC Shenyang Liming Aero Engine Co Ltd
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Priority to CN202111041926.1A priority Critical patent/CN113739877A/en
Publication of CN113739877A publication Critical patent/CN113739877A/en
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01FMEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/66Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by measuring frequency, phase shift or propagation time of electromagnetic or other waves, e.g. using ultrasonic flowmeters

Abstract

The invention relates to an ultrasonic online calibration device of a liquid flowmeter and a calibration method thereof, and the device comprises a clamp frame, a metal ball chain, a locking device and a pressing device, wherein the clamp frame is provided with scale marks and is erected on a flow pipeline, two ends of the metal ball chain are fixed on the clamp frame by bypassing the flow pipeline, one end of the metal ball chain is locked by the locking device, and the flow pipeline is fixed with the clamp frame; the liquid flowmeter is arranged on the frame clamp, and the upper part of the liquid flowmeter is pressed by the pressing device. The invention utilizes the liquid flowmeter online calibrating device to calibrate the liquid flowmeter, can save and avoid the problems of unmatched joints, liquid leakage, unchanged turnover and unstable reinstallation of a calibration pipeline in a flowmeter laboratory, ensures the good working state of the liquid flowmeter and simultaneously meets the traceability requirement.

Description

Ultrasonic method online calibration device and method for liquid flowmeter
Technical Field
The invention belongs to the technical field of liquid flowmeter calibration, and particularly relates to an ultrasonic method online calibration device and a calibration method for a liquid flowmeter.
Background
There are four problems with calibrating flow meters under laboratory conditions: firstly, the most common connection mode of the flowmeter and the pipeline mainly comprises two modes of threaded connection and flange connection, and the phenomenon that the structure of a flow standard device is not matched with the connection mode of a calibrated flowmeter can occur in the measurement of the actual flowmeter, so that the measurement is difficult; secondly, liquid media in the pipeline are inevitably discharged in the process of disassembling the liquid flowmeter, so that waste is caused; thirdly, some large-caliber flow meters have large volume and heavy mass, and are inconvenient to transport and inspect; fourthly, air enters the air pipeline when the air pipeline is installed again after calibration, so that the measurement result is unstable, and air needs to be removed after a period of time of operation. Therefore, there is a need for an online calibration device and method for a liquid flow meter.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides the ultrasonic method online calibration device and the ultrasonic method online calibration method for the liquid flowmeter, which can be used for direct online calibration without damaging a pipeline.
An ultrasonic online calibration device of a liquid flowmeter comprises a clamp frame, a metal ball chain, a locking device and a pressing device, wherein scale marks are arranged on the clamp frame and erected on a flow pipeline; the liquid flowmeter is arranged on the frame clamp, and the upper part of the liquid flowmeter is pressed by the pressing device.
The bottom of the fixing frame is provided with an upward notch, so that a space is provided for placing a flow pipeline during online calibration.
The fixture frame comprises two fixing frames and a scale, two ends of the scale are respectively fixed on the two fixing frames, and the flow pipeline and the scale are arranged in parallel; the scale mark is arranged on the scale; the scale comprises two parts which are arranged in parallel, wherein one part is provided with scale marks; the fixing frame is provided with a waist-shaped hole, and two parts of the scale are respectively fixed in the waist-shaped hole and locked by a locking nut; the distance between the two parts of the scale can be adjusted through the waist-shaped hole, so that the liquid flowmeter can be better placed.
The locking device comprises a spring, a base and a locking sleeve, the base comprises a cylindrical sliding block and a locking seat, external threads are arranged at the upper part of the cylindrical sliding block, internal threads are arranged in the locking sleeve, and the cylindrical sliding block penetrates through the locking seat to be in threaded connection with the locking sleeve; the spring is arranged between the bottom of the locking sleeve and the upper surface of the base; a rectangular hole is formed in the upper part of the fixing frame, and the cylindrical sliding block is placed in the rectangular hole; the bottom of the cylindrical sliding block is provided with a locking hole, and one end of the metal ball chain is placed in the locking hole and locked by a locking sleeve; the fixing frame is provided with a fixing hole for clamping the other end of the metal ball chain, and one end of the metal ball chain is clamped in the fixing hole.
The bottom surface of the locking seat is a sector surface, the upper surface of the cylindrical sliding block is provided with a sector groove, and the sector surface is matched with the sector groove.
The pressing device comprises a support frame and a pressing nut, the support frame is erected on the upper portion of the fixture frame, and the pressing nut penetrates through the upper portion of the support frame and is pressed on the upper portion of the liquid flowmeter.
The online calibration method of the online calibration device for the liquid flowmeter by the ultrasonic method is characterized by comprising the following steps of:
the method comprises the following steps: clamp mounting
Erecting a fixture frame on a clean flow pipeline, and adjusting a locking nut on the side surface of a fixing frame of the fixture frame to enable a probe of the ultrasonic flowmeter to be just placed between two parts of a scale; one end of a metal ball chain penetrates into a locking hole of a locking device, the other end of the metal ball chain bypasses a flow pipeline and is clamped into a fixing hole after being tensioned, a locking sleeve is screwed, the locking sleeve drives a cylindrical sliding block to move upwards through threads, namely, the cylindrical sliding block is close to the locking sleeve, and the metal ball chain is tightened, so that a clamp frame is firmly fixed on the flow pipeline;
step two: ultrasonic probe mounting
Uniformly coating an ultrasonic coupling agent on the flow pipeline, then placing the two ultrasonic probes between the two parts of the scale, and adjusting the positions of the two ultrasonic probes until ultrasonic signals are fed back; then, erecting a support frame of the pressing device on a fixture frame, moving the support frame to the position above the ultrasonic probes, screwing down a pressing nut, pressing the pressing nut to the position above the ultrasonic probes, and fixing the two ultrasonic probes;
step three: flow measurement
Selecting a V-shaped time difference method for flow measurement, setting and confirming the outer diameter, the wall thickness, the material quality, the roughness, the medium type, the temperature, the ultrasonic probe distance and the sound path of a flow pipeline on a setting interface of the ultrasonic flowmeter, namely measuring the flow of the fluid in the flow pipeline through the ultrasonic flowmeter; and comparing the measured actual flow of the liquid in the flow pipeline with the display flow of the liquid flowmeter in the flow pipeline, thereby realizing the calibration of the calibrated liquid flowmeter.
The invention has the beneficial effects that: the invention utilizes the liquid flowmeter online calibrating device to calibrate the liquid flowmeter, can save and avoid the problems of unmatched joints, liquid leakage, unchanged turnover and unstable reinstallation of a calibration pipeline in a flowmeter laboratory, ensures the good working state of the liquid flowmeter and simultaneously meets the traceability requirement.
Drawings
FIG. 1 is a top view of an in-line calibration apparatus of the present invention;
FIG. 2 is a side view of an in-line calibration apparatus of the present invention;
FIG. 3 is a schematic view of a pressing device of the on-line calibration device of the present invention;
wherein the content of the first and second substances,
1-clamp frame, 1-1-fixing frame, 1-2-scale, 2-metal ball chain, 3-locking device, 4-pressing device, 5-graduation line, 6-notch, 7-locking nut, 8-spring, 9-base, 10-column slide block, 11-locking base, 12-rectangular hole, 13-fixing hole, 14-locking sleeve, 15-supporting frame and 16-pressing nut.
Detailed Description
For better understanding of the present invention, the technical solutions and effects of the present invention will be described in detail by the following embodiments with reference to the accompanying drawings.
Starting from the principle of online calibration of the liquid flowmeter, the online calibration method comprises a direct measurement method and an indirect measurement method. The direct measurement method is to connect a higher-precision flowmeter into a calibrated flowmeter pipeline, and take the flowmeter as a standard flowmeter to simultaneously measure the liquid flow with the calibrated flowmeter. The direct measurement method needs to modify a measurement pipeline for measurement and reserves a standard flowmeter measurement interface. The indirect measurement method is to utilize the propagation of sound waves in a liquid medium, a time difference occurs in transmission due to the influence of forward flow and reverse flow of the liquid medium, and the flow of the liquid medium is obtained by calculating the conversion relation between the time difference and the flow speed of the liquid medium. The indirect measurement method does not need to measure a reserved joint of the pipeline, only needs to measure the length of the pipeline with proper straight pipe section, and adopts a direct method.
As shown in fig. 1, the ultrasonic online calibration device for the liquid flowmeter comprises a clamp frame 1, a metal ball chain 2, a locking device 3 and a pressing device 4, wherein scale marks 5 are arranged on the clamp frame 1 and erected on a flow pipeline, two ends of the metal ball chain 2 bypass the flow pipeline and are fixed on the clamp frame 1, one end of the metal ball chain is locked by the locking device 3, and the flow pipeline and the clamp frame 1 are fixed. The liquid flowmeter is arranged on the frame fixture, and the upper part of the liquid flowmeter is pressed by the pressing device 4.
An upward notch 6 is formed at the bottom of the fixing frame 1-1, so that space is provided for placing a flow pipeline during online calibration.
The fixture frame 1 comprises two fixing frames 1-1 and a scale 1-2, two ends of the scale 1-2 are respectively fixed on the two fixing frames 1-1, and the flow pipeline and the scale 1-2 are arranged in parallel. The scale mark 5 is arranged on the scale 1-2. The scale 1-2 comprises two parts which are arranged in parallel, wherein one part is provided with scale marks 5; the fixing frame 1-1 is provided with a waist-shaped hole, and the two parts of the scale 1-2 are respectively fixed in the waist-shaped hole and locked by a locking nut 7. The distance between the two parts of the scale 1-2 can be adjusted through the waist-shaped hole, so that the liquid flowmeter can be better placed.
As shown in fig. 2, the locking device 3 includes a spring 8, a base 9 and a locking sleeve 14, the base 9 includes a cylindrical sliding block 10 and a locking seat 11, an external thread is provided on the upper portion of the cylindrical sliding block 10, an internal thread is provided inside the locking sleeve, the cylindrical sliding block 10 passes through the locking seat 11 and is in threaded connection with the locking sleeve 14, the spring is disposed between the bottom of the locking sleeve 14 and the upper surface of the base 9, namely, the spring is sleeved outside the external thread of the cylindrical sliding block 10; a rectangular hole 12 is formed in the upper portion of the fixing frame 1-1, the cylindrical sliding block 10 is placed in the rectangular hole 12, and the cylindrical sliding block 10 and the locking seat 11 can slide in the rectangular hole 12; the bottom of the cylindrical sliding block 10 is provided with a locking hole, and one end of the metal ball chain 2 is placed in the locking hole and locked by a locking sleeve 14. The fixing frame 1-1 is provided with a fixing hole 13 for clamping the other end of the metal ball chain 2, the fixing hole 13 is communicated with the side face of the fixing frame 1-1 through a strip-shaped hole, and one end of the metal ball chain 2 is inserted into the strip-shaped hole and clamped in the fixing hole 13. The bottom surface of the locking seat 11 is a sector surface, the upper surface of the cylindrical sliding block 10 is provided with a sector groove, and the sector surface is matched with the sector groove.
As shown in fig. 3, the pressing device 4 includes a support frame 15 and a pressing nut 16, the support frame 15 is mounted on the upper portion of the fixture frame 1, and the pressing nut 16 penetrates through the upper portion of the support frame 15 and presses on the upper portion of the liquid flow meter.
The method for carrying out online calibration on the ultrasonic online calibration device of the liquid flowmeter specifically comprises the following steps:
the method comprises the following steps: clamp mounting
The clamp frame 1 is erected on a clean flow pipeline, the flow pipeline is placed in a gap 6 at the bottom of two fixing frames 1-1, and a locking nut 7 on the side face of the fixing frame 1-1 of the clamp frame 1 is adjusted to enable a probe of the ultrasonic flowmeter to be just placed between the two parts of the scale 1-2. One end of the metal ball chain 2 penetrates into a locking hole of the locking device 3, the other end of the metal ball chain 2 bypasses the flow pipeline and is clamped into the fixing hole 13 after being tensioned, the locking sleeve 14 is screwed, the locking sleeve 14 drives the cylindrical sliding block 10 to move upwards through threads to be close to the locking sleeve 14, and the metal ball chain 2 is tightened, so that the clamp frame 1 is firmly fixed on the flow pipeline.
Step two: ultrasonic probe mounting
Uniformly coating an ultrasonic coupling agent on the flow pipeline, then placing the two ultrasonic probes between the two parts of the scale 1-2, and adjusting the positions of the two ultrasonic probes until ultrasonic signals are fed back; then, the support frame 15 of the hold-down device 4 is erected on the jig frame 1 and moved above the ultrasonic probes, the hold-down nut 16 is tightened, the hold-down nut 16 is held down above the ultrasonic probes, and the two ultrasonic probes are fixed.
Step three: flow measurement and calculation
The method comprises the steps of selecting a V-shaped time difference method to carry out flow measurement, setting and confirming the outer diameter, the wall thickness, the material and the roughness of a flow pipeline, the medium type, the temperature, the distance between ultrasonic probes and the sound path (scale reading) of a measured fluid on a setting interface of an ultrasonic flowmeter, and measuring the flow of the fluid in the flow pipeline through the ultrasonic flowmeter.
The online calibration device for the liquid flowmeter realizes online calibration of the liquid flowmeter and coupling and positioning of the ultrasonic flowmeter and the flow pipeline; measuring the accurate distance between the ultrasonic probes through a scale; measuring the liquid flow velocity of the flow pipeline by a V-shaped time difference method, thereby calculating the actual flow of the liquid in the pipeline; and comparing the measured actual flow of the liquid in the flow pipeline with the display flow of the liquid flowmeter in the flow pipeline, thereby realizing the calibration of the calibrated liquid flowmeter.

Claims (7)

1. The utility model provides a liquid flowmeter supersound method online calibrating device which characterized in that: the clamp comprises a clamp frame, a metal ball chain, a locking device and a pressing device, wherein scale marks are arranged on the clamp frame and erected on a flow pipeline, two ends of the metal ball chain bypass the flow pipeline and are fixed on the clamp frame, and one end of the metal ball chain is locked by the locking device and fixes the flow pipeline and the clamp frame; the liquid flowmeter is arranged on the frame clamp, and the upper part of the liquid flowmeter is pressed by the pressing device.
2. The ultrasonic online calibration device for the liquid flowmeter as claimed in claim 1, wherein: the bottom of the fixing frame is provided with an upward notch, so that a space is provided for placing a flow pipeline during online calibration.
3. The ultrasonic online calibration device for the liquid flowmeter as claimed in claim 1, wherein: the fixture frame comprises two fixing frames and a scale, two ends of the scale are respectively fixed on the two fixing frames, and the flow pipeline and the scale are arranged in parallel; the scale mark is arranged on the scale; the scale comprises two parts which are arranged in parallel, wherein one part is provided with scale marks; the fixing frame is provided with a waist-shaped hole, and two parts of the scale are respectively fixed in the waist-shaped hole and locked by a locking nut; the distance between the two parts of the scale can be adjusted through the waist-shaped hole, so that the liquid flowmeter can be better placed.
4. The ultrasonic online calibration device for the liquid flowmeter as claimed in claim 1, wherein: the locking device comprises a spring, a base and a locking sleeve, the base comprises a cylindrical sliding block and a locking seat, external threads are arranged at the upper part of the cylindrical sliding block, internal threads are arranged in the locking sleeve, and the cylindrical sliding block penetrates through the locking seat to be in threaded connection with the locking sleeve; the spring is arranged between the bottom of the locking sleeve and the upper surface of the base; a rectangular hole is formed in the upper part of the fixing frame, and the cylindrical sliding block is placed in the rectangular hole; the bottom of the cylindrical sliding block is provided with a locking hole, and one end of the metal ball chain is placed in the locking hole and locked by a locking sleeve; the fixing frame is provided with a fixing hole for clamping the other end of the metal ball chain, and one end of the metal ball chain is clamped in the fixing hole.
5. The ultrasonic online calibration device for the liquid flowmeter as claimed in claim 4, wherein: the bottom surface of the locking seat is a sector surface, the upper surface of the cylindrical sliding block is provided with a sector groove, and the sector surface is matched with the sector groove.
6. The ultrasonic online calibration device for the liquid flowmeter as claimed in claim 1, wherein: the pressing device comprises a support frame and a pressing nut, the support frame is erected on the upper portion of the fixture frame, and the pressing nut penetrates through the upper portion of the support frame and is pressed on the upper portion of the liquid flowmeter.
7. The method for calibrating the ultrasonic online calibration device of the liquid flowmeter according to any one of claims 1-6, comprising the steps of:
the method comprises the following steps: clamp mounting
Erecting a fixture frame on a clean flow pipeline, and adjusting a locking nut on the side surface of a fixing frame of the fixture frame to enable a probe of the ultrasonic flowmeter to be just placed between two parts of a scale; one end of a metal ball chain penetrates into a locking hole of a locking device, the other end of the metal ball chain bypasses a flow pipeline and is clamped into a fixing hole after being tensioned, a locking sleeve is screwed, the locking sleeve drives a cylindrical sliding block to move upwards through threads, namely, the cylindrical sliding block is close to the locking sleeve, and the metal ball chain is tightened, so that a clamp frame is firmly fixed on the flow pipeline;
step two: ultrasonic probe mounting
Uniformly coating an ultrasonic coupling agent on the flow pipeline, then placing the two ultrasonic probes between the two parts of the scale, and adjusting the positions of the two ultrasonic probes until ultrasonic signals are fed back; then, erecting a support frame of the pressing device on a fixture frame, moving the support frame to the position above the ultrasonic probes, screwing down a pressing nut, pressing the pressing nut to the position above the ultrasonic probes, and fixing the two ultrasonic probes;
step three: flow measurement
Selecting a V-shaped time difference method for flow measurement, setting and confirming the outer diameter, the wall thickness, the material quality, the roughness, the medium type, the temperature, the ultrasonic probe distance and the sound path of a flow pipeline on a setting interface of the ultrasonic flowmeter, namely measuring the flow of the fluid in the flow pipeline through the ultrasonic flowmeter; and comparing the measured actual flow of the liquid in the flow pipeline with the display flow of the liquid flowmeter in the flow pipeline, thereby realizing the calibration of the calibrated liquid flowmeter.
CN202111041926.1A 2021-09-07 2021-09-07 Ultrasonic method online calibration device and method for liquid flowmeter Pending CN113739877A (en)

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Application Number Priority Date Filing Date Title
CN202111041926.1A CN113739877A (en) 2021-09-07 2021-09-07 Ultrasonic method online calibration device and method for liquid flowmeter

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Application Number Priority Date Filing Date Title
CN202111041926.1A CN113739877A (en) 2021-09-07 2021-09-07 Ultrasonic method online calibration device and method for liquid flowmeter

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CN113739877A true CN113739877A (en) 2021-12-03

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103471665A (en) * 2012-06-07 2013-12-25 中国石油化工股份有限公司 Ultrasonic online detection device and method for liquid flow
US20140216166A1 (en) * 2011-06-24 2014-08-07 Avl List Gmbh Method for determining the flow rate of fluids using the ultrasonic transit time method
CN204594513U (en) * 2015-04-03 2015-08-26 福建宁德核电有限公司 A kind of probe positioning installation apparatus of ultrasonic flow meter
CN207798172U (en) * 2018-01-31 2018-08-31 深圳市深科工程检测有限公司 A kind of probe gripper of hand-held ultrasonic flowmeter
US20190137310A1 (en) * 2017-06-05 2019-05-09 Cong Xiao Compact ultrasonic flowmeter with adjustment for various flow diameters
CN212747953U (en) * 2020-09-16 2021-03-19 上海市供水水表强制检定站有限公司 Ultrasonic flowmeter for on-line calibration of large-caliber electronic water meter

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140216166A1 (en) * 2011-06-24 2014-08-07 Avl List Gmbh Method for determining the flow rate of fluids using the ultrasonic transit time method
CN103471665A (en) * 2012-06-07 2013-12-25 中国石油化工股份有限公司 Ultrasonic online detection device and method for liquid flow
CN204594513U (en) * 2015-04-03 2015-08-26 福建宁德核电有限公司 A kind of probe positioning installation apparatus of ultrasonic flow meter
US20190137310A1 (en) * 2017-06-05 2019-05-09 Cong Xiao Compact ultrasonic flowmeter with adjustment for various flow diameters
CN207798172U (en) * 2018-01-31 2018-08-31 深圳市深科工程检测有限公司 A kind of probe gripper of hand-held ultrasonic flowmeter
CN212747953U (en) * 2020-09-16 2021-03-19 上海市供水水表强制检定站有限公司 Ultrasonic flowmeter for on-line calibration of large-caliber electronic water meter

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