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CN109387265A - Low temperature mass flowmenter performance testing device and method - Google Patents

Low temperature mass flowmenter performance testing device and method Download PDF

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Publication number
CN109387265A
CN109387265A CN201710674551.XA CN201710674551A CN109387265A CN 109387265 A CN109387265 A CN 109387265A CN 201710674551 A CN201710674551 A CN 201710674551A CN 109387265 A CN109387265 A CN 109387265A
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CN
China
Prior art keywords
liquid
low
valve
commutator
mass flowmenter
Prior art date
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Pending
Application number
CN201710674551.XA
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Chinese (zh)
Inventor
许光
张健中
王振中
周日峰
蒲鹤
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
China Petroleum and Chemical Corp
Sinopec Qingdao Safety Engineering Institute
Original Assignee
China Petroleum and Chemical Corp
Sinopec Qingdao Safety Engineering Institute
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by China Petroleum and Chemical Corp, Sinopec Qingdao Safety Engineering Institute filed Critical China Petroleum and Chemical Corp
Priority to CN201710674551.XA priority Critical patent/CN109387265A/en
Publication of CN109387265A publication Critical patent/CN109387265A/en
Pending legal-status Critical Current

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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01FMEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F25/00Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume

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  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)

Abstract

本发明涉及一种低温质量流量计性能测试装置及方法,主要解决现有技术中安全性较低、准确度较低的问题。本发明通过采用一种低温质量流量计性能测试装置,包括低温储罐、潜液泵、气液分离器、被测流量计、电子天平、标准表系统、控制系统,低温储罐与潜液泵入口相连,潜液泵出口与气液分离器相连,气液分离器底部与低温储罐相连,气液分离器顶部与被测流量计入口相连,被测流量计出口与标准表系统相连,标准表系统与换向器相连,换向器与电子天平上的储液瓶相连;控制系统与被测流量计、标准表系统、天子天平、潜液泵、换向器相连及方法的技术方案较好地解决了上述问题,可用于低温质量流量计性能测试中。

The invention relates to a low temperature mass flowmeter performance testing device and method, which mainly solve the problems of low safety and low accuracy in the prior art. The present invention adopts a low-temperature mass flowmeter performance testing device, including a low-temperature storage tank, a submersible pump, a gas-liquid separator, a measured flowmeter, an electronic balance, a standard meter system, a control system, a low-temperature storage tank and a submersible pump The inlet is connected, the outlet of the submersible pump is connected to the gas-liquid separator, the bottom of the gas-liquid separator is connected to the low temperature storage tank, the top of the gas-liquid separator is connected to the inlet of the measured flowmeter, and the outlet of the measured flowmeter is connected to the standard meter system. The meter system is connected with the commutator, the commutator is connected with the liquid storage bottle on the electronic balance; the control system is connected with the measured flowmeter, the standard meter system, the Tianzi balance, the submersible pump, and the commutator. It solves the above problems well and can be used in the performance test of low temperature mass flow meters.

Description

Low temperature mass flowmenter performance testing device and method
Technical field
The present invention relates to a kind of low temperature mass flowmenter performance testing device and methods.
Background technique
Coriolis low temperature mass flowmenter is unique measuring equipment in LNG gas station, the measuring accuracy of the flowmeter Etc. performances directly affect the fairness of trading, it is therefore necessary to periodically carry out accuracy correction.Detection approach common at present There are mainly two types of: first, directly carry out the accuracy detection of method of standard table, but this method to flowmeter by equipment in gas station Waste caused by the normal operation and LNG that will affect gas station first excessively vaporize, additionally there are some potential safety problemss;The Two, flowmeter is individually detected by test device, i.e., precision calibration is carried out to flowmeter by method of standard table.Due to Current and exclusive calibrating specification clearly detects medium, therefore many enterprises are replaced using water gauge, determine cryogenic flow by water gauge Meter, can only simulate the mobility of LNG, can not material property and mechanical performance of the detection stream meter under low temperature, environment with pressure. There is no for the cryogenic flow meter pertinent literature that standard scale detects under cryogenic media at present.
Summary of the invention
The first technical problem to be solved by the present invention is the problem that safety in the prior art is lower, accuracy is lower, A kind of new low temperature mass flowmenter performance testing device is provided.The device has the advantages that safety is higher, accuracy is higher. The second technical problem to be solved by the present invention is to provide one kind and corresponding low temperature quality stream one of the technical issues of solution Meter performance test methods.
One of in order to solve the above problem, The technical solution adopted by the invention is as follows: a kind of low temperature mass flowmenter performance is surveyed Trial assembly is set, including low-temperature storage tank, immersed pump, gas-liquid separator, measured stream meter, electronic balance, standard scale system, control system System, low-temperature storage tank are connected with immersed pump entrance, and immersed pump outlet is connected with gas-liquid separator, and gas-liquid separator bottom and low temperature store up Tank is connected, and is included in mouth with measured flux at the top of gas-liquid separator and is connected, and the outlet of measured stream meter is connected with standard scale system, standard Table system is connected with commutator, and commutator is connected with the liquid storage bottle on electronic balance;Control system and measured stream meter, standard scale System, emperor's balance, immersed pump, commutator are connected
In above-mentioned technical proposal, it is preferable that be equipped at least one liquid feed valve before each measured stream meter pipeline.
In above-mentioned technical proposal, it is preferable that be equipped with liquid feed valve before the immersed pump entrance.
In above-mentioned technical proposal, it is preferable that the pipeline that the gas-liquid separator bottom returns to low-temperature storage tank is equipped with exhaust Pipeline, exhaust line are equipped with diffusion valve and needle valve.
In order to solve the above problem two, The technical solution adopted by the invention is as follows: a kind of low temperature mass flowmenter performance is surveyed Method for testing carries out the performance test of low temperature mass flowmenter using low temperature mass flowmenter performance testing device, includes the following steps:
(1) stage is pre-chilled in equipment;
Immersed pump is pre-chilled first, liquid feed valve A and time liquid valve A are opened, and liquid feed valve B is closed, and liquid nitrogen enters immersed pump Pump pond after, immersed pump low-frequency start, liquid nitrogen flows in immersed pump, gas-liquid separator, low-temperature storage tank and related pipeline at this time Dynamic pre-cooling;It is then shut off back liquid valve A, liquid feed valve B, time liquid valve B and corresponding liquid feed valve C, commutator is opened and switches to back liquid Pipeline, liquid nitrogen flows separately through measured stream meter, commutator after gas-liquid separator at this time, finally returns in low-temperature storage tank, thus Complete the pre-cooling work of method of standard table test line;Pass through the switching of commutator, moreover it is possible to complete to the pre- of the liquid storage bottle of mass method It is cold;
(2) the performance test stage;
1) method of standard table is tested: being opened liquid feed valve A, liquid feed valve B, liquid feed valve C and is returned liquid valve B, closes back liquid valve A, liquid It after nitrogen flows through measured stream meter and standard scale system from low-temperature storage tank, then through commutator and returns liquid valve B and returns to low-temperature storage tank, during which Flowmeter and the signal of standard scale system have carried out related operation and processing by control system acquisition, to realize standard To the performance test of mass flowmenter under table method, wherein measured stream meter pipeline is able to achieve using simultaneously column distribution to different bores The test of flowmeter;
2) mass method is tested: being opened liquid feed valve A, liquid feed valve B, liquid feed valve C and is returned liquid valve B, closes back liquid valve A, commutate Device switches over, and liquid nitrogen flows through measured stream meter from low-temperature storage tank, and subsequently into liquid storage bottle, electronic balance can be to servicing fluids Nitrogen is timed, quantitative weighing, compares with measured stream meter, to complete the test of mass method;After the completion of weighing, liquid nitrogen exists Home discharge.
In above-mentioned technical proposal, it is preferable that the capital equipment in the standard scale system is measuring accuracy higher quality Flowmeter, for demarcating tested mass flowmenter precision.
In above-mentioned technical proposal, it is preferable that commutator allows hand over the flow direction of liquid nitrogen, commutator one end and gas-liquid separator Bottom liquid phases pipeline is connected.
In above-mentioned technical proposal, it is preferable that electronic balance and liquid storage bottle are the capital equipments of mass method, for filling Liquid nitrogen is weighed.
In above-mentioned technical proposal, it is preferable that mass method test is also able to achieve the test of tracing to the source to standard scale.
The present invention has method of standard table and two kinds of mass method detections to realize the performance detection under liquid nitrogen environment to flowmeter Method may be implemented to install the performance test of different size flowmeter using skid, simple and efficient, easy to operate, achieve Preferable technical effect.
Detailed description of the invention
Fig. 1 is the flow diagram of device of the present invention.
In Fig. 1,1-low-temperature storage tank;2-return liquid valve A;3-liquid feed valve A;4-immersed pumps;5-diffusion valves;6-needle-like Valve;7-return liquid valve B;8-gas-liquid separators;9-liquid feed valve B;10- measured stream meter extension bits;11-standard scale systems; 12-commutators;13-electronic balances and liquid storage bottle;14-control systems;15-measured stream meters;16-liquid feed valve C.
The present invention will be further described below by way of examples, but is not limited only to the present embodiment.
Specific embodiment
[embodiment 1]
A kind of low temperature mass flowmenter performance test methods carry out low temperature using low temperature mass flowmenter performance testing device Mass flowmenter performance test, the low temperature mass flowmenter performance testing device include low-temperature storage tank, immersed pump, gas-liquid separation Device, measured stream meter, electronic balance, standard scale system, control system, low-temperature storage tank are connected with immersed pump entrance, and immersed pump goes out Mouth is connected with gas-liquid separator, and gas-liquid separator bottom is connected with low-temperature storage tank, is included at the top of gas-liquid separator with measured flux Mouth is connected, and the outlet of measured stream meter is connected with standard scale system, and standard scale system is connected with commutator, commutator and electronic balance On liquid storage bottle be connected;Control system is connected with measured stream meter, standard scale system, emperor's balance, immersed pump, commutator.
Capital equipment in standard scale system is measuring accuracy higher quality flowmeter, for demarcating tested mass flow Count precision.
Commutator allows hand over the flow direction of liquid nitrogen, and commutator one end is connected with gas-liquid separator bottom liquid phases pipeline.
Electronic balance and liquid storage bottle are the capital equipments of mass method, for weighing to the liquid nitrogen of filling.
At least one liquid feed valve is equipped with before each measured stream meter pipeline.
Liquid feed valve is equipped with before the immersed pump entrance.
The pipeline that the gas-liquid separator bottom returns to low-temperature storage tank is equipped with exhaust line, and exhaust line is equipped with release Valve and needle valve.
When carrying out the performance test of low temperature mass flowmenter, include the following steps:
(1) stage is pre-chilled in equipment;
Immersed pump is pre-chilled first, liquid feed valve A and time liquid valve A are opened, and liquid feed valve B is closed, and liquid nitrogen enters immersed pump Pump pond after, immersed pump low-frequency start, liquid nitrogen flows in immersed pump, gas-liquid separator, low-temperature storage tank and related pipeline at this time Dynamic pre-cooling;It is then shut off back liquid valve A, liquid feed valve B, time liquid valve B and corresponding liquid feed valve C, commutator is opened and switches to back liquid Pipeline, liquid nitrogen flows separately through measured stream meter, commutator after gas-liquid separator at this time, finally returns in low-temperature storage tank, thus Complete the pre-cooling work of method of standard table test line;Pass through the switching of commutator, moreover it is possible to complete to the pre- of the liquid storage bottle of mass method It is cold;
(2) the performance test stage;
1) method of standard table is tested: being opened liquid feed valve A, liquid feed valve B, liquid feed valve C and is returned liquid valve B, closes back liquid valve A, liquid It after nitrogen flows through measured stream meter and standard scale system from low-temperature storage tank, then through commutator and returns liquid valve B and returns to low-temperature storage tank, during which Flowmeter and the signal of standard scale system have carried out related operation and processing by control system acquisition, to realize standard To the performance test of mass flowmenter under table method, wherein measured stream meter pipeline is able to achieve using simultaneously column distribution to different bores The test of flowmeter;
2) mass method is tested: being opened liquid feed valve A, liquid feed valve B, liquid feed valve C and is returned liquid valve B, closes back liquid valve A, commutate Device switches over, and liquid nitrogen flows through measured stream meter from low-temperature storage tank, and subsequently into liquid storage bottle, electronic balance can be to servicing fluids Nitrogen is timed, quantitative weighing, compares with measured stream meter, to complete the test of mass method;After the completion of weighing, liquid nitrogen exists Home discharge;Mass method test is also able to achieve the test of tracing to the source to standard scale.
The present invention has method of standard table and two kinds of mass method detections to realize the performance detection under liquid nitrogen environment to flowmeter Method may be implemented to install the performance test of different size flowmeter using skid, simple and efficient, easy to operate, achieve Preferable technical effect.

Claims (9)

1. a kind of low temperature mass flowmenter performance testing device, including low-temperature storage tank, immersed pump, gas-liquid separator, measured flux Meter, electronic balance, standard scale system, control system, low-temperature storage tank are connected with immersed pump entrance, immersed pump outlet and gas-liquid separation Device is connected, and gas-liquid separator bottom is connected with low-temperature storage tank, is included in mouth with measured flux at the top of gas-liquid separator and is connected, measured stream Meter outlet is connected with standard scale system, and standard scale system is connected with commutator, commutator and the liquid storage bottle phase on electronic balance Even;Control system is connected with measured stream meter, standard scale system, emperor's balance, immersed pump, commutator.
2. low temperature mass flowmenter performance testing device according to claim 1, it is characterised in that each measured stream meter pipe At least one liquid feed valve is equipped with before line.
3. low temperature mass flowmenter performance testing device according to claim 1, it is characterised in that before the immersed pump entrance Equipped with liquid feed valve.
4. low temperature mass flowmenter performance testing device according to claim 1, it is characterised in that the gas-liquid separator bottom The pipeline that portion returns to low-temperature storage tank is equipped with exhaust line, and exhaust line is equipped with diffusion valve and needle valve.
5. a kind of low temperature mass flowmenter performance test methods are surveyed using low temperature mass flowmenter performance described in claim 1 Trial assembly, which is set, carries out the performance test of low temperature mass flowmenter, includes the following steps:
(1) stage is pre-chilled in equipment;
Immersed pump is pre-chilled first, liquid feed valve A and time liquid valve A are opened, and liquid feed valve B is closed, and liquid nitrogen enters the pump of immersed pump Chi Hou, immersed pump low-frequency start, at this time liquid nitrogen flowing in immersed pump, gas-liquid separator, low-temperature storage tank and related pipeline are pre- It is cold;It is then shut off back liquid valve A, liquid feed valve B, time liquid valve B and corresponding liquid feed valve C, commutator is opened and switches to liquid back pipe line, Liquid nitrogen flows separately through measured stream meter, commutator after gas-liquid separator at this time, finally returns in low-temperature storage tank, to complete to mark The pre-cooling work of quasi- table method test line;Pass through the switching of commutator, moreover it is possible to complete the pre-cooling to the liquid storage bottle of mass method;
(2) the performance test stage;
1) method of standard table is tested: being opened liquid feed valve A, liquid feed valve B, liquid feed valve C and is returned liquid valve B, closes back liquid valve A, liquid nitrogen is certainly After low-temperature storage tank flows through measured stream meter and standard scale system, then through commutator and returns liquid valve B and return to low-temperature storage tank, during which flow Meter and the signal of standard scale system have carried out related operation and processing by control system acquisition, to realize method of standard table Under performance test to mass flowmenter, wherein measured stream meter pipeline using and column distribution, be able to achieve to different bore flows The test of meter;
2) mass method is tested: open liquid feed valve A, liquid feed valve B, liquid feed valve C and return liquid valve B, close back liquid valve A, commutator into Row switching, liquid nitrogen flows through measured stream meter from low-temperature storage tank, subsequently into liquid storage bottle, electronic balance can to filling liquid nitrogen into Row timing, quantitative weighing, compare with measured stream meter, to complete the test of mass method;After the completion of weighing, liquid nitrogen is in safety Position discharge.
6. low temperature mass flowmenter performance test methods according to claim 5, it is characterised in that in the standard scale system Capital equipment be measuring accuracy higher quality flowmeter, for demarcating tested mass flowmenter precision.
7. low temperature mass flowmenter performance test methods according to claim 5, it is characterised in that commutator allows hand over liquid The flow direction of nitrogen, commutator one end are connected with gas-liquid separator bottom liquid phases pipeline.
8. low temperature mass flowmenter performance test methods according to claim 5, it is characterised in that electronic balance and liquid storage bottle It is the capital equipment of mass method, for weighing to the liquid nitrogen of filling.
9. low temperature mass flowmenter performance test methods according to claim 5, it is characterised in that mass method test can also be real Now to the test of tracing to the source of standard scale.
CN201710674551.XA 2017-08-09 2017-08-09 Low temperature mass flowmenter performance testing device and method Pending CN109387265A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113252144A (en) * 2021-02-11 2021-08-13 烟台中隆仪表有限公司 Ultralow-temperature liquid static mass method calibration device and method thereof
CN113758546A (en) * 2021-09-23 2021-12-07 深圳市质量安全检验检测研究院 Flowmeter calibrating device and method and flowmeter assembly to be measured
CN114088169A (en) * 2021-11-09 2022-02-25 浙江浙能富兴燃料有限公司 Air pressure driven liquid hydrogen flow standard device adopting bidirectional mass method
CN114910143A (en) * 2022-05-27 2022-08-16 成都安迪生测量有限公司 Low-temperature liquid flow performance test system and test method thereof

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101556181A (en) * 2009-05-20 2009-10-14 西安东风机电有限公司 Composite static start-stop method mass flowmeter calibration system
CN103411653A (en) * 2013-08-30 2013-11-27 福建恒劲科博测控技术有限公司 Calibration and detection device of liquid flow meter
CN104501916A (en) * 2014-12-08 2015-04-08 西尼尔(南京)过程控制有限公司 Liquid calibration system and calibration method thereof
CN205173982U (en) * 2015-12-11 2016-04-20 重庆市计量质量检测研究院 Switching -over valve formula quality method cryogenic liquids flow rate standard facility
CN105823532A (en) * 2016-05-16 2016-08-03 上海裕凡实业有限公司 Mobile flow online calibrating system
CN106124006A (en) * 2016-06-16 2016-11-16 日照海达尔加气设备有限公司 A kind of High Precision Low Temperature effusion meter detecting system and method thereof
CN106679770A (en) * 2016-11-22 2017-05-17 重庆川仪自动化股份有限公司 Mass calibration system and method for mass flow meter
CN206387478U (en) * 2016-12-08 2017-08-08 中国石油化工股份有限公司 A kind of oiling machine flow meter performance testing device
CN207066556U (en) * 2017-08-09 2018-03-02 中国石油化工股份有限公司 Low temperature mass flowmenter performance testing device

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101556181A (en) * 2009-05-20 2009-10-14 西安东风机电有限公司 Composite static start-stop method mass flowmeter calibration system
CN103411653A (en) * 2013-08-30 2013-11-27 福建恒劲科博测控技术有限公司 Calibration and detection device of liquid flow meter
CN104501916A (en) * 2014-12-08 2015-04-08 西尼尔(南京)过程控制有限公司 Liquid calibration system and calibration method thereof
CN205173982U (en) * 2015-12-11 2016-04-20 重庆市计量质量检测研究院 Switching -over valve formula quality method cryogenic liquids flow rate standard facility
CN105823532A (en) * 2016-05-16 2016-08-03 上海裕凡实业有限公司 Mobile flow online calibrating system
CN106124006A (en) * 2016-06-16 2016-11-16 日照海达尔加气设备有限公司 A kind of High Precision Low Temperature effusion meter detecting system and method thereof
CN106679770A (en) * 2016-11-22 2017-05-17 重庆川仪自动化股份有限公司 Mass calibration system and method for mass flow meter
CN206387478U (en) * 2016-12-08 2017-08-08 中国石油化工股份有限公司 A kind of oiling machine flow meter performance testing device
CN207066556U (en) * 2017-08-09 2018-03-02 中国石油化工股份有限公司 Low temperature mass flowmenter performance testing device

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113252144A (en) * 2021-02-11 2021-08-13 烟台中隆仪表有限公司 Ultralow-temperature liquid static mass method calibration device and method thereof
CN113758546A (en) * 2021-09-23 2021-12-07 深圳市质量安全检验检测研究院 Flowmeter calibrating device and method and flowmeter assembly to be measured
CN114088169A (en) * 2021-11-09 2022-02-25 浙江浙能富兴燃料有限公司 Air pressure driven liquid hydrogen flow standard device adopting bidirectional mass method
CN114088169B (en) * 2021-11-09 2023-08-04 浙江浙能富兴燃料有限公司 A two-way mass method liquid hydrogen flow standard device driven by air pressure
CN114910143A (en) * 2022-05-27 2022-08-16 成都安迪生测量有限公司 Low-temperature liquid flow performance test system and test method thereof

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Application publication date: 20190226