CN208595954U - A kind of natural gas big flow reality stream calibrating installation - Google Patents

A kind of natural gas big flow reality stream calibrating installation Download PDF

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Publication number
CN208595954U
CN208595954U CN201821080201.7U CN201821080201U CN208595954U CN 208595954 U CN208595954 U CN 208595954U CN 201821080201 U CN201821080201 U CN 201821080201U CN 208595954 U CN208595954 U CN 208595954U
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header
flowmeter
natural gas
pipeline
detection pipeline
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姚欣伟
任晓峰
王登海
孙志鹏
吴宝祥
刘晓丽
王东
白岩
张昆
白东丰
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Xian Changqing Technology Engineering Co Ltd
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Xian Changqing Technology Engineering Co Ltd
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Abstract

The utility model discloses a kind of natural gas big flows to flow calibrating installation in fact, it is characterized by comprising the first headers (3) and the second header (11), first header (3) is connected with air inlet (1), first header (3) is connected with the detection pipeline that 4 tunnels are set side by side, and the detection pipeline other end is connected to the second header (11);Second header (11) is also connected with verification table position (13), the verification table position (13) is connected on third header (12), third header (12) is connected to exhaust outlet (10), small flow section detection pipeline is wherein also connected between air inlet (1) and the second header (11), it is successively arranged rectifier (4), turbine flowmeter (6) and rotz flowmeter (7) on small flow section detection pipeline, rectifier (4), ultrasonic flowmeter (5) and turbine flowmeter (6) are successively arranged on the detection pipeline.The utility model long-time stability are high, improve systematic jitters and price is lower.

Description

A kind of natural gas big flow reality stream calibrating installation
Technical field
The utility model belongs to gas metering field, and in particular to a kind of natural gas big flow reality stream calibrating installation.
Background technique
Currently, domestic natural gas trade transaction flowmeter such as ultrasonic flowmeter, turbine flowmeter etc. (tested flowmeter) It is all made of method of standard table (working stamndard) and carries out real stream compulsory verification, calibration, the systematic uncertainty of working stamndard is reachable 0.33%, standard scale is all made of 0.25 grade of high-precision gas turbine flowmeter.To real the stream compulsory verification, school of work grade standard table Standard, the main second unit using critical flow nozzle composition in parallel carry out real stream calibrating, the systematic uncertainty of second unit It can achieve 0.25%.The critical flow nozzle of second unit then by the simple standard of mt method (systematic uncertainty up to 0.1% ~ 0.05%) real stream compulsory verification is carried out, perfect transmission of quantity value system is formed:
The work grade standard of domestic natural gas measurement verification website by one or more groups of parallel connections high-precision turbine flow Meter composition, per the electronic forced seal ball for all the way further including verification flowmeter, straight pipe, rectifier, expansion bend and respective line Valve.Different work grade standard flowmeters is selected to be combined according to the point of flow required for tested flowmeter, such as Fig. 2.
According to the range ability of accredited flowmeter, (range of flow of 50mm ~ 300mm is about 10 ~ 8000 m3/ h), work Stage arrangement needs to select different bore turbine flowmeters and determines the number of turbines of each bore.The whirlpool of domestic work grade standard at present Flowmeters mainly select 3 m of 250mm(130 ~ 25003/ h), 1 m of 150mm(50 ~ 5003/ h) and 1 80mm(20 ~ 2500 m3/ h) bore be combined, gamut can examine and determine 50mm ~ 300mm(10 ~ 8000m3/ h) tested flowmeter.
But following problems exist in the prior art:
1) when small flow verification, increasing that the big tube capacity between grade standard flowmeter and tested flowmeter that works can be obvious Adding the uncertainty of entire verification system influences.Therefore, when work grade standard examines and determine tested flowmeter, it is responsible for small flow section calibrating Small-bore turbine flowmeter and tested flowmeter between exist work grade standard downstream header big tube capacity influence.
2) according to the facilities of domestic work grade standard at present, usually selecting diameter is the turbine flowmeter conduct of 80mm Small-bore proving flowmeter, due to the design feature of turbine flowmeter itself, the long-time stability of small flow section are poor, i.e., long The error change amount deviation of phase is larger, and stability is lower.
3) especially more per working the purging of grade standard all the way and blowdown piping is required to that hand-operated forced seal ball-valve is arranged When group turbine flowmeter parallel connection, high investment.
Utility model content
It is high that the purpose of the utility model is to provide a kind of calibrating accuracy, and long-time stability are strong and investment is low with maintenance cost Natural gas big flow stream calibrating installation in fact.
Above-mentioned purpose is implemented with the following technical solutions in the utility model:
The utility model provides a kind of natural gas big flow stream calibrating installation, including the first header and the second header in fact, institute It states the first header to be connected with air inlet, the first header is connected with the detection pipeline that multichannel is set side by side, and the another of pipeline is detected on every road One end is connected to the second header, and every road detection pipeline is successively arranged rectifier, supersonic flow on from the first header to the second header Meter and turbine flowmeter;Second header is also connected with verification table position, and the verification table position is connected on third header, and third is converged Pipe is connected to exhaust outlet, and small flow section detection pipeline, small flow section detection pipe are wherein also connected between air inlet and the second header Include two forced seal ball valves positioned at both ends on line, and positioned at two force rectifier between seal ball-valves on pipeline, Turbine flowmeter and rotz flowmeter.
Further, the first header is equipped with nitrogen purge line, and the second header is equipped with blow-down pipe.
Further, forced seal ball is equipped between the rectifier and the first header on the detection pipeline of the first header connection Valve also is provided with forced seal ball valve between turbine flowmeter and the second header.
Further, the detection pipeline of the first header connection is divided into 4 tunnels, and verification table position is divided into 5 tunnels, and Road downstream is set There are two third header two-way to share a third header, and the another way of verification table position is directly connect with exhaust outlet, the calibrating Platform position both ends are equipped with forced seal ball valve.
Further, the turbine flowmeter and ultrasonic flowmeter in pipeline, turbine flowmeter and ultrasound in 3 tunnels are detected in road Wave flowmeter diameter is 250mm, and the turbine flowmeter and ultrasonic flowmeter diameter in road are 50mm.The small flow section Turbine flowmeter and rotz flowmeter diameter on detection pipeline are 100mm.
Further, the second header is also connected with secondary standard device, and secondary standard device is connected to exhaust outlet.
Further, 5 Lu Taiwei pipe diameters of verification table position are respectively 250mm, 300mm, 200mm, 50mm, 100mm.
The utility model has the following beneficial effects:
(1) small flow section detection pipeline detects pipeline independently of other 4 tunnels, and upstream directly takes gas from air inlet, downstream with Second header outlet be connected, can either participate in heavy caliber be detected flowmeter calibration operation, can also be individually for diameter 100mm with Lower small mouth diameter is detected flowmeter and is examined and determine, and reduces intermediate tube capacity when small-caliber flow meter calibrating, individually examines and determine diameter Tube capacity about 2.54m can be reduced when 100mm or less small-caliber flow meter3, improve systematic uncertainty.
(2) 1 rotz flowmeter (100mm) is selected to replace original turbine flowmeter in small flow section detection pipeline (80mm), 5 ~ 400 m of range of flow3/ h, range is wider, and long-time stability are more preferable, and corresponding verification flowmeter selects turbine flow Meter (100mm);Remaining 4 tunnel is detected in pipeline and selects turbine flowmeter (3 250mm, 1 150mm), and range of flow is respectively 130~2500 m3/ h and 50 ~ 500 m3/ h, corresponding verification flowmeter select ultrasonic flowmeter (3 250mm, 1 150mm);Total flow range is 10 ~ 8000 m3/ h, the gamut that can satisfy 50mm ~ 300mm flowmeter are cautious.
(3) simplify each pipeline and be vented flow setting, reduce 50mm forced seal valve, shut-off valve each 5, simplify each pipeline note Nitrogen flow setting reduces 50mm forced seal valve, shut-off valve each 4, simplifies each pipeline telescopic device setting, cancels expansion bend 5, Reduce about 1,260,000 yuan of investment.It is changed to that nitrogen purge line all the way is only arranged at the first header, is arranged all the way at the second header Blow-down pipe.
Detailed description of the invention
Fig. 1 is utility model diagram;
Fig. 2 is traditional natural gas big flow stream calibrating installation flow diagram in fact.
1, air inlet in figure;2, nitrogen purge line;3, the first header;4, rectifier;5, ultrasonic flowmeter;6, turbine Flowmeter;7, rotz flowmeter;8, blow-down pipe;9, secondary standard device;10, exhaust outlet;11, the second header;13, verification table Position;14, forced seal ball valve;15, expansion bend.
Specific embodiment
[embodiment 1]
As shown in Figure 1, including the first header 3 and the second header 11, first header 3 is connected with air inlet 1, and first converges Pipe 3 is connected with the detection pipeline that multichannel is set side by side, and the other end of every road detection pipeline is connected to the second header 11, every road detection Pipeline is successively arranged rectifier 4, ultrasonic flowmeter 5 and turbine flowmeter 6 from first the 3 to the second header of header 11;Second Header 11 is also connected with verification table position 13, and the verification table position 13 is connected on third header 12, and third header 12 is connected to exhaust Mouth 10, it is characterised in that: small flow section detection pipeline, small flow section are wherein also connected between air inlet 1 and the second header 11 Include two forced seal ball valves 14 positioned at both ends on detection pipeline, and is located at two and forces between seal ball-valve 14 on pipeline Rectifier 4, turbine flowmeter 6 and rotz flowmeter 7.
Forced seal ball valve 14, inspection are equipped on the detection pipeline of first header 3 connection between rectifier 4 and the first header 3 Forced seal ball valve 14 is equipped between turbine flowmeter 6 and the second header 11 on test tube line.
Detect turbine flowmeter 6 and supersonic flow in 5,3 tunnel of turbine flowmeter 6 and ultrasonic flowmeter in pipeline in 4 tunnels 5 diameter of meter is 250mm, and the turbine flowmeter 6 and 5 diameter of ultrasonic flowmeter in 1 tunnel are 150mm.
Turbine flowmeter 6 and 7 diameter of rotz flowmeter on small flow section detection pipeline are 100mm.
The detection pipeline of first header 3 connection is divided into 4 tunnels.
Wherein the first header 3, the second header 11,4 tunnels detection pipeline arranged side by side and small flow section detection pipeline nominal are work Make grade standard device, gas enters work grade standard device from connecing in port 1, subsequently into verification table position 13, verification table position 13 for installing tested flowmeter, and final gas drains into exhaust outlet 10 from verification table position 13, final to be discharged.
And small flow section detection pipeline is independent outside 4 tunnels detection pipeline, directly connects with air inlet 1 and the second header 11 It connects, the calibration operation that heavy caliber is detected flowmeter can either be participated in this way, can also be individually for the small-bore tested stream of 100mm or less Meter is examined and determine, and is being individually for that tube capacity can be reduced about when the small-bore tested flowmeter of 100mm or less is examined and determine 2.54m3, improve systematic uncertainty.
In multichannel detection pipeline arranged side by side, the turbine flowmeter 6 on pipeline is used as work grade standard table, wherein 3 diameters 250mm, 1 150mm, the range of flow of the two are 130 ~ 2500 m respectively3/ h and 50 ~ 500 m3/h.Ultrasonic flow on pipeline Meter 5, which is used as, verifies flowmeter, wherein 3 diameter 250mm, 1 150mm, total flow range is 10 ~ 8000 m3/ h, can satisfy The gamut of 50mm ~ 300mm flowmeter is cautious.Wherein the identical turbine flowmeter 6 of diameter and ultrasonic flowmeter 5 are located at same Road.
In addition as shown in Fig. 2, domestic device all uses turbine flowmeter 6 to be used as work grade standard table, but osculum at present 6 long-time stability of turbine flowmeter of diameter are poor.
By comparison, turbine belongs to velocity flowmeter.First, blade and axis there are frictional force, small flow section some When below critical point, gas is influenced very big by frictional force, and there are certain journeys for the flow velocity of the blade rotational speed and real fluid that measure The difference of degree, measurement accuracy are poor;Second, velocity flowmeter is larger (Re=ρ vd/ μ) by Reynolds number effect, when bore d is smaller When, gas Reynolds number is smaller, and fluidised form tends to laminar flow, and balance and repdocutbility are poor, and the long-time stability of flowmeter are poor.
Waist wheel belongs to volumetric flowmeter.It is influenced by frictional force and Reynolds number smaller when small flow section, is had better Long-time stability, annual flow error variable quantity are no more than 0.05%, 100mm rotz flowmeter in 10 ~ 400m3/ h range model Error in enclosing is small (- 0.15 ~+0.25%), and the linearity is high;Stability is good, conducive to the amendment of flowmeter error.
Therefore, the grade standard table that works in independent small flow section detection pipeline uses rotz flowmeter 7, a diameter of 100mm, 5 ~ 400 m of range of flow3/ h, range is wider, and long-time stability are more preferable, and annual flow error variable quantity is no more than 0.05%.The turbine flowmeter 6 verified flowmeter and use 100mm on route.
[embodiment 2]
As shown in Figure 1, the first header 3 is equipped with nitrogen purge line 2, the second header 11 is equipped with blow-down pipe 8.
As shown in Fig. 2, forced seal should be arranged in the nitrogen purge line 2 and blow-down pipe 8 that are connected with detection pipeline Ball valve 14 guarantees zero leakage, and the general ball valve of output investment ratio of forced seal ball valve 14 is expensive, therefore this is practical by nitrogen sparge tube Line 2 and blow-down pipe 8 are separately positioned on the first header 3 and the second header 11, avoid nitrogen purge line 2 and blow-down pipe 8 with the forced seal ball valve 14 per detection pipe line all the way.It is reduced costs while purging and emptying function may be implemented.
At the same time, because infrequently dismantling after proving flowmeter installation, the utility model is eliminated per detection pipe all the way Expansion bend 15 on line.
On the whole, flow setting is vented by each pipeline of simplification, reduces 50mm forced seal valve, shut-off valve each 5, letter Change each pipeline note nitrogen flow setting, reduce 50mm forced seal valve, shut-off valve each 4, simplifies each pipeline telescopic device setting, cancel Expansion bend 5, reduce about 1,260,000 yuan of investment.
[embodiment 3]
As shown in Figure 1, verification table position 13 is divided into 5 tunnels, wherein 4 tunnel downstreams are set, there are two 12 two-way of third header to share one A third header 12, the another way of verification table position are directly connect with exhaust outlet 10, and 13 both ends of verification table position are equipped with pressure Seal ball-valve 14.
5 Lu Taiwei pipe diameters of verification table position 13 are respectively 250mm, 300mm, 200mm, 150mm, 100mm.
Wherein verification table position 13 shares 5 tunnels, for installing the tested flowmeter of different bores.According to the model of tested flowmeter It encloses, according to several flow points that the requirement selection of vertification regulation needs to examine and determine, corresponding work grade standard of opening needs combined pipe Road.The selection specifically combined is as shown in table 1.
The work grade standard flow meter of table 1 selects table
Such as shown in serial number 1, when tested flowmeter bore is 50mm ~ 100mm, the measurement range of test point be (10~ 250) m3When/h, only enables the small flow section that standard scale bore is 100mm and detect pipeline.
As shown in serial number 2, when tested flowmeter bore is 80mm ~ 100mm, the measurement range of test point is (250~400) m3When/h, enable in 4 tunnels detection pipeline, 6 bore of standard scale, that is, turbine flowmeter is that road of 150mm.
As shown in serial number 7, when tested flowmeter bore is 150mm ~ 200mm, the measurement range of test point be (1600~ 3200) m3It when/h, enables in detection pipeline, 3 road standard scales, that is, 6 bore of turbine flowmeter is 2 tunnels in 250mm.
[embodiment 4]
As shown in Figure 1, the second header 11 is also connected with secondary standard device 9, secondary standard device 9 is connected to exhaust outlet 10。
Second header 11 is also connected to existing secondary standard device 9, convenient to carry out secondary standard detection when needed, Secondary standard is discharged after having detected from exhaust outlet 10.
In conclusion attaching it to one in verification table position 13 according to the bore of tested flowmeter when needing to examine and determine The detection pipeline being connected with the first header 3 and the detection of small flow section are opened according to table 1 further according to the range of tested flowmeter in road One or more pipeline in pipeline is examined and determine, subsequently into tested flowmeter is installed in verification table position 13 all the way, later Gas outlet 10 is drained into through third header 12 or directly drains into gas outlet 10 through verification table position 13.
When calibrating, natural gas enters from air inlet 1, according to table 1, when needing the work grade table using 100mm, natural gas Directly enter in verification table position 13 through small flow section detection pipeline, is carried out by the rotz flowmeter 7 in small flow section detection pipeline Calibrating, turbine flowmeter 6 is verified, and at this time as shown in serial number 1 in table 1, is detected flowmeter bore 80-100mm, natural gas is not Through the second header 11, that pipeline that diameter in verification table position 13 is 100mm is directly entered by small flow section detection pipeline, then Natural gas is discharged from gas outlet 10.If when being detected flowmeter bore 150-200mm, natural gas is through small flow section as shown in serial number 4 It detects pipeline to enter in the second header 11, subsequently into tested that road of flowmeter is placed in verification table position 13, enters third later Then header 12 is discharged through exhaust outlet 10.
When needing the work grade table using 150mm or 250mm, natural gas enters the first header 3 through air inlet 1, according to Table 1 opens one or more in 4 tunnels calibrating pipeline, is examined and determine by turbine flowmeter 6 therein, ultrasonic flowmeter 5 is made To verify, natural gas enters the second header 11 after passing through corresponding road, enters back into verification table position 13 and installs that of tested flowmeter Road enters third header 12 later and is then discharged through exhaust outlet 10.

Claims (7)

1. a kind of natural gas big flow stream calibrating installation, including the first header (3) and the second header (11) in fact, first header (3) it is connected with air inlet (1), the first header (3) is connected with the detection pipeline that multichannel is set side by side, and the another of pipeline is detected on every road End is connected to the second header (11), and every road detection pipeline is successively arranged rectifier on from the first header (3) to the second header (11) (4), ultrasonic flowmeter (5) and turbine flowmeter (6);Second header (11) is also connected with verification table position (13), the calibrating Platform position (13) is connected on third header (12), and third header (12) is connected to exhaust outlet (10), it is characterised in that: wherein air inlet (1) it is also connected with small flow section detection pipeline between the second header (11), includes being located at both ends on small flow section detection pipeline Two forced seal ball valves (14), and be located at two and force rectifier (4) between seal ball-valve (14) on pipeline, turbine flow Meter (6) and rotz flowmeter (7).
2. a kind of natural gas big flow according to claim 1 flows calibrating installation in fact, it is characterised in that: first header (3) nitrogen purge line (2) are equipped with, the second header (11) is equipped with blow-down pipe (8).
3. a kind of natural gas big flow according to claim 1 flows calibrating installation in fact, it is characterised in that: first header (3) forced seal ball valve (14) are equipped between the rectifier (4) and the first header (3) on the detection pipeline of connection, turbine flow Forced seal ball valve (14) also are provided between meter (6) and the second header (11).
4. a kind of natural gas big flow according to claim 1 flows calibrating installation in fact, it is characterised in that: first header (3) the detection pipeline connected is divided into 4 tunnels, and verification table position (13) are divided into 5 tunnels, wherein 4 tunnel downstreams are set, there are two third headers (12) two-way shares a third header (12), and the another way of verification table position is directly connect with exhaust outlet (10), the verification table Position (13) both ends are equipped with forced seal ball valve (14).
5. a kind of natural gas big flow according to claim 4 flows calibrating installation in fact, it is characterised in that: the 4 tunnel detection Turbine flowmeter (6) and ultrasonic flowmeter (5) in pipeline, turbine flowmeter (6) and ultrasonic flowmeter (5) are straight in 3 tunnels Diameter is 250mm, and the turbine flowmeter (6) and ultrasonic flowmeter (5) diameter in 1 tunnel are 150mm;The small flow section inspection Turbine flowmeter (6) and rotz flowmeter (7) diameter on test tube line are 100mm.
6. a kind of natural gas big flow according to claim 1 flows calibrating installation in fact, it is characterised in that: second header (11) it is also connected with secondary standard device (9), secondary standard device (9) is connected to exhaust outlet (10).
7. a kind of natural gas big flow according to claim 4 flows calibrating installation in fact, it is characterised in that: the verification table position (13) 5 Lu Taiwei pipe diameters are respectively 250mm, 300mm, 200mm, 150mm, 100mm.
CN201821080201.7U 2018-07-09 2018-07-09 A kind of natural gas big flow reality stream calibrating installation Active CN208595954U (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108709609A (en) * 2018-07-09 2018-10-26 西安长庆科技工程有限责任公司 A kind of natural gas big flow is real to flow calibrating installation and method

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108709609A (en) * 2018-07-09 2018-10-26 西安长庆科技工程有限责任公司 A kind of natural gas big flow is real to flow calibrating installation and method

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