CN209570256U - Flowmeter check device - Google Patents
Flowmeter check device Download PDFInfo
- Publication number
- CN209570256U CN209570256U CN201920611793.9U CN201920611793U CN209570256U CN 209570256 U CN209570256 U CN 209570256U CN 201920611793 U CN201920611793 U CN 201920611793U CN 209570256 U CN209570256 U CN 209570256U
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- China
- Prior art keywords
- flowmeter
- temperature change
- damper
- piping
- check device
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- 238000007689 inspection Methods 0.000 claims abstract description 44
- 229910052751 metal Inorganic materials 0.000 claims description 22
- 239000002184 metal Substances 0.000 claims description 22
- 238000011144 upstream manufacturing Methods 0.000 claims description 12
- 238000005259 measurement Methods 0.000 claims description 7
- 239000012634 fragment Substances 0.000 claims description 6
- 238000005187 foaming Methods 0.000 claims description 4
- 239000006262 metallic foam Substances 0.000 claims description 4
- 238000000465 moulding Methods 0.000 claims description 2
- 239000007921 spray Substances 0.000 claims 1
- 238000004378 air conditioning Methods 0.000 abstract description 5
- 239000007789 gas Substances 0.000 description 24
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 8
- 229920000742 Cotton Polymers 0.000 description 4
- 238000002474 experimental method Methods 0.000 description 4
- 229910052742 iron Inorganic materials 0.000 description 4
- 210000002268 wool Anatomy 0.000 description 4
- 238000012790 confirmation Methods 0.000 description 3
- 239000004745 nonwoven fabric Substances 0.000 description 3
- 239000011347 resin Substances 0.000 description 3
- 229920005989 resin Polymers 0.000 description 3
- 239000002759 woven fabric Substances 0.000 description 3
- 239000011521 glass Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000011490 mineral wool Substances 0.000 description 2
- 230000000116 mitigating effect Effects 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 239000004411 aluminium Substances 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 230000004323 axial length Effects 0.000 description 1
- 239000003034 coal gas Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000002918 waste heat Substances 0.000 description 1
Landscapes
- Measuring Volume Flow (AREA)
Abstract
The utility model provides a kind of flowmeter check device of influence for being not easily susceptible to bring by the temperature change of gas.In the flowmeter check device (10) of the utility model, it is imported the atmosphere in the inspection chamber (90) for carrying out airconditioning control as inspection gas, and checks the atmosphere with piping (30) by flowing to later in temperature change damper (44).The atmosphere of importing makes temperature change because of external disturbance sometimes, but the thermal capacity of the atmosphere in the ratio of heat capacities inspection chamber (90) of temperature change damper (44) is big, therefore the temperature atmosphere changed and temperature change mitigate the variation with heat exchange is carried out between damper (44).The atmosphere for the state that temperature variation is mitigated as a result, flows through inspection piping (30), therefore in the flowmeter check device (10) of the utility model, is not easily susceptible to influence because of the temperature variation bring of atmosphere.
Description
Technical field
The utility model relates to a kind of flowmeter check devices, and the flowmeter check device is in a part by sonic nozzle structure
At inspection piping midway be connected with flowmeter, from check with piping upstream side end attract gas, progress flowmeter
Measurement precision inspection.
Background technique
The inspection method of this flowmeter is usually controlling temperature to carry out in constant inspection chamber, makes in the inspection chamber
Atmosphere flow to inspection with piping (for example, referring to patent document 1).
Citation
Patent document
Patent document 1: Japanese Unexamined Patent Publication 7-110257 bulletin ([0002], [0007] section)
However, checking that indoor temperature can change because of external disturbance sometimes, exists and check due to flowing through with piping
Atmosphere temperature change and make to check that precision is deteriorated such problems.It is therefore desirable to develop the temperature being not easily susceptible to because of gas
Change the flowmeter check device that bring influences.
Utility model content
Solution for solving the problem
The utility model of the technical solution 1 proposed for solving the above subject is a kind of flowmeter check device, the stream
Meter check device a part be made of sonic nozzle inspection with piping in ratio described in sonic nozzle on the upstream side in
Way has the flowmeter interconnecting piece connecting with the flowmeter of check object, attracts gas with the upstream side end of piping from described check
Body carries out the inspection of the measurement precision of the flowmeter, which is characterized in that the flowmeter check device has temperature change
With damper, which fills or is entrenched in flowmeter interconnecting piece described in the ratio checked in piping and lean on
The position of upstream side, the gas is by the inside of the temperature change damper, and the temperature change damper is to being passed through
The temperature change of the gas mitigated.
The utility model of technical solution 2 is flowmeter check device described in technical solution 1, which is characterized in that the temperature
Sintered body made of degree variation is metal wire rod, metal plastochondria, is sintered metal plastochondria with damper shapes metal foaming
Made of metal foam.
The utility model of technical solution 3 is flowmeter check device described in technical solution 1, which is characterized in that the inspection
It looks into bigger than the internal diameter of part in addition to this with the internal diameter of the part with the temperature change damper in piping.
The utility model of technical solution 4 is flowmeter check device described in technical solution 2, which is characterized in that the inspection
It looks into bigger than the internal diameter of part in addition to this with the internal diameter of the part with the temperature change damper in piping.
The utility model of technical solution 5 is flowmeter check device described in technical solution 2 or 4, which is characterized in that in institute
It states and has the fragment for removing the temperature change damper between temperature change damper and the flowmeter interconnecting piece
Filter.
Utility model effect
According to the flowmeter check device of technical solution 1, occurred even if being attracted to and checking with the temperature of the gas of piping
Variation, also when by checking temperature change damper had with piping, between the temperature change damper into
Row heat exchange and mitigate the temperature change of gas.In addition, the amplitude of fluctuation of the temperature variation because of gas caused by air-conditioning equipment
It is mitigated also by temperature change with damper.Further, it is possible to temperature change will be made to delay by temperature change damper
The gas of sum flows and carries out the inspection of flowmeter to flowmeter, sonic nozzle.In this way, being examined according to the flowmeter of technical solution 1
Device is looked into, the influence that the temperature change of gas when being not easily susceptible to the inspection by carry out flowmeter is brought.
As the flowmeter check device of technical solution 2, as long as temperature change damper metal wire rod, clipped wire
Body, by sintered body made of the sintering of metal plastochondria or metal foam made of shaping metal foaming, it will be able to significantly really
The contact area with gas protected in temperature change damper correspondingly can make temperature change damper compact.
In the flowmeter check device of technical solution 3,4, check in piping with temperature change damper
Partial internal diameter is bigger than the internal diameter of part in addition to this, thus can significantly ensure in temperature change damper with gas
The contact area of body can be improved the alleviating function of the temperature change of gas, improve damper function.
According to the flowmeter check device of technical solution 5, though a part of temperature change damper become fragment and
It separates, can also be captured using filter, prevent the fragment from flowing to flowmeter, sonic nozzle.
Detailed description of the invention
Fig. 1 is the top view of flowmeter check device.
Fig. 2 is the enlarged plan view in air introduction portion.
Fig. 3 is the structure chart for being provided with the inspection chamber of flowmeter check device.
Fig. 4 is the chart for indicating the result of confirmation experiment.
Description of symbols:
10 flowmeter check devices
20 flowmeters
21 flowmeter interconnecting pieces
30 check with piping
44 temperature change dampers
50 sonic nozzles
Specific embodiment
Hereinafter, referring to Fig.1~Fig. 3 is illustrated the embodiment of flowmeter check device 10.As shown in Figure 1, this reality
The flowmeter check device 10 for applying mode includes inspection piping 30, and part of it is made of sonic nozzle 50；And suction pump
51, it is connect with the inspection with the one end of piping 30.Also, with the common flowmeter check device for having used sonic nozzle
Similarly, the flowmeter check device 10 of present embodiment is also when suction pump 51 works, by the upstream side of sonic nozzle 50
The pressure ratio of pressure and downstream lateral pressure is maintained at critical pressure ratio hereinafter, by by the stream of the gas of the throat of sonic nozzle 50
Speed is fixed as velocity of sound.As long as be attracted to as a result, check with piping 30 in gas temperature be it is constant, constant flow rate (with
Under, be referred to as " standard flow ") gas can check be piped 30 in flow.It, can be in addition, in order to change standard flow
The different multiple sonic nozzles 50 of flow path cross sectional area for preparing throat, from select arbitrary sonic nozzle 50 in them and by its group
Dress uses a part of piping 30 to check.
Located on the upstream side checking with the ratio sonic nozzle 50 being piped in 30, in order to by one or more flowmeters 20 and sound
Fast nozzle 50 is connected in series and has flowmeter interconnecting piece 21.In the example of Fig. 1, a flowmeter 20 and flowmeter interconnecting piece 21
Connection.
It should be noted that the flowmeter 20 being mounted on flowmeter interconnecting piece 21 is to measure all streams of the flow of gas
Amount is calculated as object, as its typical example, such as can enumerate: the basic routing line of general home-use gas meter, flow meter or coal gas pipe network
Gas meter, flow meter and flowmeter etc. with the piping connection of chemical plant etc..In addition, the measurement principle to flowmeter 20 does not have
Limitation.That is, flowmeter 20 is such as can be for ultrasonic flowmeter, any one of Diaphram flowmeter, or they with
Outer flowmeter.
Checking that upstream end thereof is provided with internal diameter with the specific discharge meter interconnecting piece 21 being piped in 30 is bigger than other parts
Major diameter pipe portion 31A.As shown in Fig. 2, the close upstream side end in major diameter pipe portion 31A and the position close to end of downstream side are set
There is mesh component 46.It should be noted that the 46 downstream part of mesh component in the ratio downstream side in major diameter pipe portion 31A is in cone
Shape undergauge.
Temperature change damper 44 is contained between a pair of of mesh component 46.Temperature change damper 44 is usual
The wire rod of the referred to as metal wire rod of " metal wool ", for example, aluminium, copper, iron, stainless steel etc., and wire rod random coil.It needs
Bright, the line footpath of wire rod is 0.02~0.1 [mm], and density is 150~300 [kg/m3]。
It should be noted that using damper 44 instead of temperature change and as can be with the shape of " temperature change damper "
Formula is contained in the component of major diameter pipe portion 31A, can enumerate: metal plastochondria, by sintered body or will be golden made of the sintering of metal plastochondria
Belong to metal foam, honeycomb structure, punch metal made of foaming and molding etc..
It uses between damper 44 and the mesh component 46 in downstream side and has for preventing as temperature change in temperature change
With the filter 45 of the metal wire rod of damper 44 to disperse.It as filter 45, can enumerate: woven fabric, non-woven fabrics, mineral wool
Or foamed resin with continuous air bubbles structure etc..
The above content is explanation related with the structure of flowmeter check device 10 of present embodiment.Use the flowmeter
Check device 10 as follows checks flowmeter 20.As shown in figure 3, flowmeter check device 10 and common flow
It counts check device similarly, is arranged in make temperature become constant mode using the inspection chamber of the progress air conditioning of air conditioner 91
In 90, the atmosphere in the inspection chamber 90 is attracted as gas.
The atmosphere being attracted via inspection after temperature change damper 44 by using piping 30 to flowmeter 20, velocity of sound
Nozzle 50 flows.Also, in the state that the atmosphere of standard flow flows to inspection piping 30 by sonic nozzle 50, utilize stream
Meter 20 surveys its flow.At this point, checking that the reference flow magnitude for using piping 30 and 20 institute of flowmeter are real by that will flow through
The value of survey is compared, thus the measurement precision of the flow to check flowmeter 20.For example, determine flowmeter 20 measured value with
Whether the deviation of reference flow magnitude is in allowed band.
In addition, sometimes the temperature of inspection chamber 90 can set temperature due to external disturbance relative to air conditioner 91 become
It is dynamic.At the same time, inspection is entered also to be changed with the temperature of piping 30.However, in the flowmeter inspection of present embodiment
In device 10, have temperature change damper 44, becomes the atmosphere being attracted and pass through temperature change damper 44 first
Structure.The thermal capacity of atmosphere in the ratio of heat capacities inspection chamber 90 of temperature change damper 44 is big, thus in inspection chamber 90
Atmosphere will not be significantly changed with the temperature of damper 44 compared to temperature change.
Therefore, even if the temperature of the atmosphere in inspection chamber 90 becomes the setting relative to air conditioner 91 because of external disturbance
In the case where the temperature that temperature is changed, the temperature in temperature change damper 44 will not be as big in inspection chamber 90
Gas changes like that.Even if be in inspection chamber 90 as a result, relative to air conditioner 91 set temperature changed it is big
Gas, also can be by the atmosphere by mitigating the amplitude that it is changed in temperature change damper 44.That is, in present embodiment
In flowmeter check device 10, even if when the atmosphere changed in inspection chamber 90 relative to the set temperature of air conditioner 91
It, also can be by the atmosphere by mitigating temperature in temperature change damper 44 in the case where inspection is entered with piping 30
The amplitude of variation then flows to inspection piping 30.
The state mitigated with the amplitude for the variation that the atmosphere in piping 30 is its temperature is checked as a result, in this reality
It applies in the flowmeter check device 10 of mode, flows to while the atmospheric stability of standard flow can be made inspection piping 30.On in addition,
The atmosphere for stating the state that the amplitude of the variation of temperature is mitigated can also be flowed into flowmeter 20, therefore even if when use
In the case where the ultrasonic flowmeter for being particularly susceptible to the influence for the velocity flow profile brought by temperature change in low flow volume region,
Also the variation of the measured value of flow can be mitigated.That is, flowmeter check device 10 according to the present embodiment, can be not easily susceptible to
The influence brought by the temperature change of atmosphere.
In addition, because temperature change caused by external disturbance can enumerate: people passes in and out in inspection chamber 90 or other experimental rigs
Sudden caused temperature change or the periodic temperature as caused by the feedback control of air conditioner 91 as waste heat of generation etc.
Degree variation etc..It should be noted that the average value of the temperature of atmosphere becomes permanent in the temperature change as caused by feedback control
It is fixed, it is changed centered on the average value.
Here, if to be inhibited in inspection chamber 90 in inspection with not having temperature change damper 44 in piping 30
The temperature variation of atmosphere, then the installation cost based on air-conditioning equipment will become great number.In contrast, according to the present embodiment, may be used
Inhibited checking with the temperature variation of the atmosphere flowed in piping 30 with damper 44 to use more cheap temperature change.
In addition, by using the metal wire rod of " metal wool " is known as above-mentioned temperature change damper 44, so as to
It is enough significantly to ensure that the contact area with atmosphere correspondingly make temperature change damper 44 compact.
Also, the internal diameter of major diameter pipe portion 31A is bigger with the internal diameter of piping 30 than checking, therefore can significantly ensure that temperature becomes
Change the contact area for using damper 44 and gas, can be improved the alleviating function of the temperature change of atmosphere, improves damper function
Energy.
On this basis, since the downstream side of the temperature change damper 44 in major diameter pipe portion 31A has filter
45, therefore even if a part of temperature change damper 44 becomes fragment and separates, can also it utilize filter 45 will
It is captured, to prevent the fragment from flowing to flowmeter 20, sonic nozzle 50.
[confirmation experiment]
For the flowmeter check device 10 of above embodiment, go out through experimental confirmation: because gas is by checking use
The temperature change damper 44 that has of upstream end thereof of piping 30 and reduce the temperature variation.In this experiment, will
Flowmeter check device 10 is arranged in the inspection chamber 90 for having air-conditioning equipment 91, and the atmosphere in inspection chamber 90 is attracted to be examined
It looks into.At this point, temperature is arranged in the inspection in the downstream side of flowmeter 20 piping 30 near the upstream end thereof with piping 30 checking
Degree meter with temperature (room temperature) T0 before damper 44 and passes through temperature change damper 44 respectively as by temperature change
The temperature T1 of atmosphere later and be measured.
In addition, making to check that with the internal diameter (d) of piping 30 be 80mm, making the internal diameter (D) of expansion tube department 42 is 200mm.Here, make
Use filling iron cotton as temperature change damper 44, its line footpath is 0.035mm, density 200kg/m3Damper.Filling
It is equal with internal diameter (D) of expansion tube department 42 (referring to Fig. 2) in the axial length (W) of the iron cotton of major diameter pipe portion 31A.
In fig. 4 it is shown that the measurement result of T0 and T1.By the measurement result it is found that room temperature T0 generating period changes,
Its variable quantity (Δ T0) is about 0.2 DEG C.In contrast, it is known that: pass through the temperature change temperature of the atmosphere after damper 44
T1 is also changed with same period, but its variable quantity (Δ T1) is about 0.15 DEG C, and temperature variation is reduced to 75%.In this experiment
It in flowmeter check device 10, can be confirmed: by having iron cotton as temperature change damper 44, being flowed into inspection and use
The temperature variation of the atmosphere of piping 30 is reduced relative to the temperature variation of room temperature.
[other embodiments]
It (1) in the above-described embodiment, can also be with although having used metal wool as temperature change damper 44
Use metal honeycomb structure or punched-plate.As embodiment described above, as long as using metal wool, it will be able to compact
Structure expand with the contact area of atmosphere, the efficiency of the heat exchange of atmosphere that can be improved and pass through.
(2) in the above-described embodiment, although temperature change damper 44 Yu downstream side mesh component 46 it
Between configure the filter 45 that is made of woven fabric, non-woven fabrics, mineral wool or foamed resin with continuous air bubbles structure etc., prevent
Only as the structure of the metal wire rod of temperature change damper 44 dispersed but it is also possible to be woven fabric, non-woven fabrics, glass will be passed through
Glass cotton or the foamed resin with continuous air bubbles structure etc. cover temperature change and are housed in large-diameter pipe with the structure of damper 44
The structure between a pair of of mesh component 46 in portion 31A.
Claims (5)
1. a kind of flowmeter check device, in the inspection spray of the velocity of sound described in the ratio in piping that a part is made of sonic nozzle
The midway of mouth on the upstream side has the flowmeter interconnecting piece connecting with the flowmeter of check object, uses the upper of piping from described check
Trip side end attracts gas to carry out the inspection of the measurement precision of the flowmeter, which is characterized in that
The flowmeter check device has temperature change damper, which fills or be entrenched in described
Check the position of flowmeter interconnecting piece on the upstream side described in the ratio in piping, the gas passes through the temperature change damper
Inside, which is mitigated with temperature change of the damper to the gas passed through.
2. flowmeter check device according to claim 1, which is characterized in that
Sintered body made of the temperature change is metal wire rod, metal plastochondria, is sintered metal plastochondria with damper will be golden
Belong to metal foam made of foaming and molding.
3. flowmeter check device according to claim 1, which is characterized in that
It is described to check with the internal diameter of the part with the temperature change damper in piping than part in addition to this
Internal diameter is big.
4. flowmeter check device according to claim 2, which is characterized in that
It is described to check with the internal diameter of the part with the temperature change damper in piping than part in addition to this
Internal diameter is big.
5. flowmeter check device according to claim 2 or 4, which is characterized in that
Has the removal temperature change damper between temperature change damper and the flowmeter interconnecting piece
Fragment filter.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2019-023472 | 2019-02-13 | ||
| JP2019023472A JP2020134160A (en) | 2019-02-13 | 2019-02-13 | Flow meter inspection device and inspection method of flow meter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN209570256U true CN209570256U (en) | 2019-11-01 |
Family
ID=68335644
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201920611793.9U Active CN209570256U (en) | 2019-02-13 | 2019-04-29 | Flowmeter check device |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP2020134160A (en) |
| CN (1) | CN209570256U (en) |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3366075B2 (en) * | 1993-10-12 | 2003-01-14 | 独立行政法人産業技術総合研究所 | Gas meter test equipment |
| JP3738830B2 (en) * | 2001-08-28 | 2006-01-25 | 財団法人理工学振興会 | Device for measuring flow rate characteristics of gas equipment and method for measuring flow rate characteristics |
| JP4020399B2 (en) * | 2004-08-25 | 2007-12-12 | 財団法人理工学振興会 | Compressive fluid continuous unsteady flow generation device, continuous unsteady flow generation method, and compressible fluid flow meter verification device |
| JP4747302B2 (en) * | 2006-09-20 | 2011-08-17 | 国立大学法人東京工業大学 | Compressive fluid continuous unsteady flow generation device, continuous unsteady flow generation method, and compressible fluid flow meter verification device |
| JP5822302B2 (en) * | 2012-01-12 | 2015-11-24 | 東京瓦斯株式会社 | Gas meter characteristic evaluation test apparatus and characteristic evaluation test method |
-
2019
- 2019-02-13 JP JP2019023472A patent/JP2020134160A/en active Pending
- 2019-04-29 CN CN201920611793.9U patent/CN209570256U/en active Active
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| Publication number | Publication date |
|---|---|
| JP2020134160A (en) | 2020-08-31 |
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