CN215909939U - Small-size intelligent on-site gas flow standard device - Google Patents
Small-size intelligent on-site gas flow standard device Download PDFInfo
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- CN215909939U CN215909939U CN202122136165.XU CN202122136165U CN215909939U CN 215909939 U CN215909939 U CN 215909939U CN 202122136165 U CN202122136165 U CN 202122136165U CN 215909939 U CN215909939 U CN 215909939U
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Abstract
The utility model relates to a small intelligent field gas flow standard device.A stagnation container is designed into a cubic base from a traditional cylinder, so that the dual functions of flow stabilization and stability are achieved, and a foundation is provided for the overall vertical design of the device; a waist wheel flowmeter without a straight pipe section requirement is selected for vertical superposition, and an electric butterfly valve with smaller thickness is arranged to realize volume compression; the CFD technology is utilized to carry out simulation analysis on different pipeline arrangements, and the opening position and the reducing design of the pipeline are determined according to the flow velocity distribution of fluid in the pipeline, so that the integral precision of the device is ensured; the convergence rectifying system is integrally welded, so that field modularized disassembly and assembly are avoided, and detection procedures are reduced. The utility model can be suitable for the field verification and calibration of gas meters with all specifications and models and gas meters with DN100 calibers and below, has high integration, can be loaded without field assembly or commercial vehicles, has a truckle assistance type, and is used for the one-key intelligent verification of the gas flow instrument.
Description
Technical Field
The utility model relates to detection equipment, in particular to a small intelligent field gas flow standard device.
Background
The existing gas flow standard devices on the market are divided into two categories. One type is a fixed gas flow standard device, which generally occupies a large area and is immobile. One is a movable gas flow standard device, and most of the standard devices are skid-mounted or modularized. The skid-mounted device is large in size and heavy in weight, and needs a special vehicle or a crane to be matched with the skid-mounted device for moving, so that the matching cost is high; most of the modularized devices are of a flat type, modularized assembly and debugging are required to be carried out after the modularized devices are located on the site, and time and labor are wasted in field installation. The above devices all require manual setting of the detection scheme according to the characteristics of the gas flowmeter to be detected.
SUMMERY OF THE UTILITY MODEL
The utility model aims to solve the technical problem of reducing the volume and the mass of the device and provide a small intelligent field gas flow standard device which is highly integrated, can be loaded without field assembly or commercial vehicles and is used for one-key intelligent verification of a gas flow instrument.
The utility model has the conception that the stagnation container is designed into a cubic base from a traditional cylinder, so that the double functions of flow stabilization and stability are achieved, and a foundation is provided for the overall vertical design of the device; a waist wheel flowmeter without a straight pipe section requirement is selected for vertical superposition, and an electric butterfly valve with smaller thickness is arranged to realize volume compression; the CFD technology is utilized to carry out simulation analysis on different pipeline arrangements, and the opening position and the reducing design of the pipeline are determined according to the flow velocity distribution of fluid in the pipeline, so that the integral precision of the device is ensured; the convergence rectifying system is integrally welded, so that field modularized disassembly and assembly are avoided, and detection procedures are reduced; the truckle assistance type design is adopted, so that hoisting or manual carrying is avoided, and convenience and flexibility in assembly and disassembly are ensured; various data acquisition modules are designed, the verification process is optimized, one-key intelligent detection is realized, and the operation is simple, convenient and quick; in the gas flow standard device with the same volume, the flow measurement range is wide, the device is suitable for the field verification and calibration of gas meters with all specifications and models and gas meters with DN100 calibers and below, and the purpose of researching and developing a small intelligent field detection device is finally realized through the conception.
The technical scheme of the utility model is as follows:
a small intelligent field gas flow standard device comprises a gas source power system, a convergence rectification system, a standard meter and a compensation system;
the air source power system comprises a fan and a frequency converter, the air outlet end of the fan is connected with the first stagnation container through a pipeline, and the frequency converter is connected with the fan to control the flow;
the convergence rectifying system comprises a first stagnation container, a manifold, a second stagnation container, a first switch butterfly valve, a second switch butterfly valve and a pipeline; one side of the first stagnation container is connected with the fan through a pipeline, and the other side of the first stagnation container is provided with two outlets which are respectively connected with the standard meter; the first switch butterfly valve and the second switch butterfly valve are connected in series on a pipeline between the first stagnation container and the standard meter, the second stagnation container is arranged between the standard meter and a pipeline of the to-be-detected meter, the upstream of the second stagnation container is connected with the pipeline of the standard meter through a collecting pipe, and the downstream of the second stagnation container is connected with the pipeline of the to-be-detected meter;
the standard meter comprises two standard flowmeters, namely a first standard flowmeter and a second standard flowmeter, wherein the first standard flowmeter and the second standard flowmeter are designed in parallel; the detected meter comprises a detected flowmeter;
the compensation system comprises a temperature and humidity sensor, an atmospheric pressure sensor, a first pressure sensor, a second pressure sensor, a third pressure sensor, a first temperature sensor, a second temperature sensor and a third temperature sensor, the temperature and humidity sensor is installed on the inner side of the control box, the atmospheric pressure sensor is installed above the control box, the first pressure sensor, the second pressure sensor and the third pressure sensor are respectively installed on the standard flowmeter and the upstream of the detected flowmeter, and the first temperature sensor, the second temperature sensor and the third temperature sensor are respectively installed on the standard flowmeter and the downstream of the detected flowmeter.
Preferably, the first stagnation container is a cylinder, the inlet is arranged at the forward position of the device, the second stagnation container is a cuboid, the second stagnation container is arranged below the standard meter and the first stagnation container, two ports are arranged at the centers of two opposite side surfaces of the second stagnation container, the inlet is connected with a junction pipe at the downstream of the standard meter, the junction pipeline is a smooth elbow pipe, and the outlet is connected with the meter to be detected.
Preferably, a flow guide plate is added at the joint of the header and the second stagnation container.
Preferably, casters are installed below the second stagnation container.
Preferably, the first switch butterfly valve and the second switch butterfly valve are electric wafer type soft seal butterfly valves.
Preferably, the CFD technology is used for simulating the inlet direction of the device, two schemes of a front inlet and a side inlet are preliminarily designed, the simulation result shows that vortexes are generated in the lateral inlet scheme device, the speed distribution at the standard table is uneven, the vortexes in the forward inlet scheme device are less, and the flow field is stable.
As a further improvement of the utility model: the CFD technology is used for simulating the forward inlet position of the device, two schemes of secondarily designing the inlet height to be 500mm away from the bottom surface and the inlet height to be 445mm away from the bottom surface are adopted, and the simulation result shows that the position flow of the inlet height to be 445mm away from the bottom surface is close to full development compared with the position flow of the inlet height to be 500mm away from the bottom surface.
As a further improvement of the utility model: two standard meter pipelines of the device are simulated by utilizing the CFD technology, and the maximum inlet flow is taken to be 650m3Performing numerical simulation on DN100 standard table pipeline at a speed of 100m3Performing numerical simulation on DN50 standard table pipeline by virtue of CFD simulationAfter the pipeline of the device is optimized and adjusted, the flow field and the outlet flow field at the standard meter are close to fully developed flow, the CFD simulation technology is utilized to determine that when a DN50 is used for verifying the pipeline, the tested meter is arranged at a position which is 3 times of the diameter of the outlet of the stagnation container 11 and is fully developed, and when a DN100 is used for verifying the pipeline, the tested meter is arranged at a position which is 4 times of the diameter of the outlet of the stagnation container 11 and is fully developed.
As a further improvement of the utility model: the range of the standard meter system can be selected from 0.65-650 m3And h, the standard gauge combination mode adopts two different gas Roots flowmeters with different calibers and flow measurement ranges to carry out combined measurement, the calibers of the standard gauge pipelines on the upper detection pipeline are DN50, the calibers of the standard gauge pipelines on the lower detection pipeline are DN100, and the ranges of the two standard gauges are 0.65-100 m for carrying out the full-blown thin ingot and 4-650 m for carrying out the full-blown thin ingot respectively.
As a further improvement of the utility model: the fan is a high-pressure centrifugal machine, and the flow range is 0.5-1300 m3The pressure can reach 20 kPa.
As a further improvement of the utility model: the standard device constructs a flow-instrument coefficient function relation on the basis of carrying out high-density fixed-point measurement on a standard meter, and realizes non-fixed-point use.
As a further improvement of the utility model: the standard device optimizes the automatic verification process and realizes one-key intelligent verification.
The utility model has the beneficial effects that:
(1) through manifold transformation and CFD flow field simulation, adopt vertical stack design mode, greatly reduced the volume and the area of device, size control is 1150mm 1050mm 1150mm, and the whole device can be loaded with ordinary commercial car, has got rid of the dependence to special supporting vehicle, is favorable to the witnessed inspections to be popularized.
(2) The device realizes high integration, avoids on-site modularized disassembly and assembly, saves working procedures and reduces time cost.
(3) The device is integrally designed in a trundle assistance mode, hoisting or manual carrying is avoided, and field flexible movement can be achieved only by single pushing.
(4) Various data acquisition modules are designed, and a detection scheme can be automatically generated only after basic information of the detected flowmeter is input, so that one-key intelligent detection is realized, and the operation is simple, convenient and quick.
(5) In the gas flow standard device with the same volume, the flow measurement range is wide, and the device is suitable for the field verification and calibration of gas meters with all specifications and models and gas meters with DN100 calibers and below.
Drawings
FIG. 1 is a front view of the apparatus of the present invention;
figure 2 top view of the utility model device;
FIG. 3 is a schematic diagram of the device of the present invention;
FIG. 4 is a vertical velocity profile of the inlet, center, and outlet cross-sections of the first standard flowmeter 4;
FIG. 5 is a vertical velocity profile of the inlet, center, and outlet cross-sections of a second standard flowmeter 8;
fig. 6 flow Q =100m3Velocity distribution maps at different positions of an outlet pipeline of the lower device;
fig. 7 flow Q =650m3Velocity profiles at different positions of the outlet pipeline of the lower device.
In the attached drawing, 1-a first stagnation container, 2-a first switch butterfly valve, 3-a first pressure sensor, 4-a first standard flow meter, 5-a first temperature sensor, 6-a header, 7-a second temperature sensor, 8-a second standard flow meter, 9-a second pressure sensor, 10-a second switch butterfly valve, 11-a second stagnation container, 12-a third pressure sensor, 13-a detected meter, 14-a third temperature sensor, 15-a fan, 16-a frequency converter, 17-a temperature and humidity transmitter, 18-an atmospheric pressure transmitter and 19-a control box.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
In the description of this patent, it is noted that the orientations are as follows: up, down, left, right, etc., in the following positions: inside, outside, etc., the pipe diameters are as follows: DN100 and DN50, and the flow ranges are as follows: the specific quantities 0.65-100 m/h, 4-650 m/h and other heights, lengths, etc. are for convenience of describing the present patent, and are not limited to specific orientations, locations, apertures, flow ranges and sizes, and thus should not be construed as limiting the present patent.
Referring to fig. 1 and fig. 2, the present embodiment provides a small intelligent field gas flow standard device, which includes a gas source power system, a convergence rectification system, a standard meter system and a compensation system.
The air source power system comprises a fan 15 and a frequency converter 16, the air outlet end of the fan 15 is connected with the first stagnation container 1 through a pipeline, the frequency converter 16 is connected with the fan 15 to control the flow, the fan 15 adopts a high-pressure centrifugal machine, and the flow range is 0.5-1300 m3The pressure can reach 20 kPa.
The convergence rectifying system comprises a first stagnation container 1, a header 6, a second stagnation container 11, a first switch butterfly valve 2, a second switch butterfly valve 10 and a pipeline part, wherein one side of the first stagnation container 1 is connected with a fan 15 through a pipeline, the other side of the first stagnation container is provided with two outlets which are respectively connected with pipelines of two standard meters, the first switch butterfly valve 2 and the second switch butterfly valve 10 are respectively connected in series on two pipelines between the first stagnation container 1 and the standard meters, the second stagnation container 11 is designed between the standard meters and pipelines of a tested meter 13, the upstream of the stagnation container 11 is connected with the pipelines of the two standard meters through the header 6, and the downstream of the stagnation container is connected with the pipelines of the tested meter 13.
The standard meter system comprises two standard flowmeters, the first standard flowmeter 4 and the second standard flowmeter 8 are designed in parallel, and the range of the standard meter system can be selected to be 0.65-650 m3And h, the standard gauge combination mode adopts two different gas Roots flowmeters with different calibers and flow measurement ranges to carry out combined measurement, the calibers of the standard gauge pipelines on the upper detection pipeline are DN50, the calibers of the standard gauge pipelines on the lower detection pipeline are DN100, and the ranges of the two standard gauges are 0.65-100 m for carrying out the full-blown thin ingot and 4-650 m for carrying out the full-blown thin ingot respectively.
The compensation system comprises a temperature and humidity sensor 17, an atmospheric pressure sensor 18, a first pressure sensor 3, a second pressure sensor 9, a third pressure sensor 12, a first temperature sensor 5, a second temperature sensor 7 and a third temperature sensor 14, wherein the temperature and humidity sensor 17 is installed on the inner side of a control box 19, the atmospheric pressure sensor 18 is installed above the control box 19, the first pressure sensor 3, the second pressure sensor 9 and the third pressure sensor 12 are respectively installed on the upstream of a standard flowmeter and a detected flowmeter, and the first temperature sensor 5, the second temperature sensor 7 and the third temperature sensor 14 are respectively installed on the downstream of the standard flowmeter and the detected flowmeter.
In this embodiment, the CFD technology is used to simulate the inlet direction of the device, and two schemes, namely a front inlet and a side inlet, are preliminarily designed, so that the simulation result shows that a vortex is generated in the lateral inlet scheme device, the speed distribution at the position of the standard meter 13 is uneven, the vortex is less in the forward inlet scheme device, and the flow field is stable.
In this embodiment, the CFD technology is used to simulate the forward inlet position of the device, and two schemes, i.e., the inlet height is 500mm away from the bottom surface and the inlet height is 445mm away from the bottom surface, are designed secondarily, and the simulation result shows that the flow at the position where the inlet height is 445mm away from the bottom surface is more nearly fully developed than the flow at the position where the inlet height is 500mm away from the bottom surface.
In this embodiment, the CFD technique is used to simulate the pipelines of two standard tables of the device, and the maximum inlet flow is taken to be 650m3Performing numerical simulation on the pipeline of the DN100 standard table by adopting the/h method, and taking the maximum inlet flow of 100m3The method comprises the steps that numerical simulation is carried out on DN50 standard meter pipelines, after CFD simulation is carried out on pipelines of the device, flow fields at a first standard flowmeter 4 and a second standard flowmeter 8 and an outlet flow field are close to fully developed flow (figures 4 and 5), the CFD simulation technology is utilized to determine that when a DN50 is used for verifying the pipelines, a detected meter is installed at a position which is 3 times of the diameter of an outlet of a second stagnation container 11 and fully developed by flowing (figure 6), and when a DN100 is used for verifying the pipelines, a detected meter 13 is installed at a position which is 4 times of the diameter of the outlet of the second stagnation container 11 and fully developed by flowing (figure 7).
In this embodiment, the first stagnation container 1 is a cylinder, the inlet is installed at the forward position of the device, the distance between the inlet and the bottom is 445mm, the second stagnation container 11 is a cuboid, the inlet is installed below the first stagnation container 1 and the pipeline of the standard meter 8, the second stagnation container 11 is provided with two ports at the central positions of two opposite side surfaces, the inlet is connected with the junction 6 at the downstream of the pipeline of the standard meter 8, the pipeline at the junction is a smooth elbow, the outlet is connected with the pipeline of the tested meter 13, the length of the second stagnation container 11 is 800mm, the width is determined as 700mm by CFD simulation, and the height is 200 mm.
In the embodiment, a reducing pipeline is additionally arranged at the joint of the DN50 verification pipeline and the manifold 6, and a guide plate is additionally arranged at the joint of the manifold 6 and the second stagnation container 11.
In this embodiment, a silent caster is mounted below the second stagnation container 11.
In the embodiment, the first switch butterfly valve 2 and the second switch butterfly valve 10 adopt electric wafer type soft seal butterfly valves with small thickness.
In the embodiment, the standard device constructs a flow-instrument coefficient function relation on the basis of performing high-density fixed-point measurement on the standard meter, so that non-fixed-point use is realized.
The standard device in the embodiment optimizes the automatic verification process, and realizes one-key intelligent verification.
The working principle and the operation process of the utility model are as follows:
in the same time interval, gas continuously flows through the standard flowmeter and the detected flowmeter, the mass flow rates of the gas flowing through the standard flowmeter and the detected flowmeter are the same according to a mass conservation law, the working condition volume flow rate of the standard flowmeter is converted into the state of the detected flowmeter through temperature and pressure conversion, and the indication error of the detected flowmeter is calculated by combining the data recorded by the detected flowmeter.
a. And installing the detected flowmeter, automatically generating a detection scheme by the system according to the type and the flow range of the flowmeter, pressing a confirmation key, automatically selecting to open a proper switch butterfly valve by the device, and setting a frequency converter to adjust to a required flow point.
b. The gas of the gas source flows through the first stagnation container 1, the standard meter, the manifold 6, the second stagnation container 11 and the detected pipeline, and the detection is automatically started after the pressure and the temperature of the gas flow are stable.
c. And measuring temperature, pressure, flow, atmospheric pressure and environment temperature and humidity signals at the standard flowmeter and the detected flowmeter by using a signal acquisition system, performing related data processing, and comparing instantaneous flow or accumulated flow values continuously passing through the standard flowmeter and the detected flowmeter within the same time interval to obtain an indication error of the detected flowmeter.
d. And after the detection scheme is executed, determining the metering performance of the detected flowmeter, automatically generating and storing a report, and finishing the detection.
Although the preferred embodiments of the present patent have been described in detail, the present patent is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present patent within the knowledge of those skilled in the art.
Claims (5)
1. A small intelligent field gas flow standard device is characterized by comprising a gas source power system, a convergence rectification system, a standard meter and a compensation system;
the air source power system comprises a fan (15) and a frequency converter (16), the air outlet end of the fan (15) is connected with the first stagnation container (1) through a pipeline, and the frequency converter (16) is connected with the fan (15) to control the flow;
the convergence rectifying system comprises a first stagnation container (1), a header (6), a second stagnation container (11), a first switch butterfly valve (2), a second switch butterfly valve (10) and a pipeline; one side of the first stagnation container (1) is connected with a fan (15) through a pipeline, and the other side of the first stagnation container is provided with two outlets which are respectively connected with a standard meter; the first switch butterfly valve (2) and the second switch butterfly valve (10) are connected in series on a pipeline between the first stagnation container (1) and the standard meter, the second stagnation container (11) is arranged between the standard meter and a pipeline of the meter to be detected (13), the upstream of the second stagnation container (11) is connected with the pipeline of the standard meter through a collecting pipe (6), and the downstream of the second stagnation container is connected with the pipeline of the meter to be detected (13);
the standard meter comprises two standard flowmeters, namely a first standard flowmeter (4) and a second standard flowmeter (8), wherein the first standard flowmeter (4) and the second standard flowmeter (8) are designed in parallel; the detected meter (13) comprises a detected flowmeter;
the compensation system comprises a temperature and humidity sensor (17), an atmospheric pressure sensor (18), a first pressure sensor (3), a second pressure sensor (9), a third pressure sensor (12), a first temperature sensor (5), a second temperature sensor (7) and a third temperature sensor (14), wherein the temperature and humidity sensor (17) is installed on the inner side of a control box (19), the atmospheric pressure sensor (18) is installed above the control box (19), the first pressure sensor (3), the second pressure sensor (9) and the third pressure sensor (12) are respectively installed on a standard flowmeter and the upstream of a detected flowmeter, and the first temperature sensor (5), the second temperature sensor (7) and the third temperature sensor (14) are respectively installed on the downstream of the standard flowmeter and the detected flowmeter.
2. A small intelligent on-site gas flow standard device according to claim 1, wherein the first stagnation container (1) is a cylinder, the second stagnation container (11) is a cuboid, the second stagnation container (11) is installed below the standard meter and the first stagnation container (1), the second stagnation container (11) is provided with two ports at the center of two opposite side surfaces, the inlet is connected with a manifold (6) at the downstream of the standard meter, a pipeline at the connection is a smooth elbow, and the outlet is connected with a meter to be detected (13).
3. A small intelligent onsite gas flow calibration device according to claim 1, wherein a baffle is added to the junction of said header (6) and said second stagnation vessel (11).
4. A small intelligent onsite gas flow standard device according to claim 1, wherein casters are mounted below the second stagnation vessel (11).
5. A small smart field gas flow calibration device according to claim 1, wherein said first (2) and second (10) switch butterfly valves are electrically operated wafer-type soft seal butterfly valves.
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| CN202122136165.XU CN215909939U (en) | 2021-09-06 | 2021-09-06 | Small-size intelligent on-site gas flow standard device |
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| CN202122136165.XU CN215909939U (en) | 2021-09-06 | 2021-09-06 | Small-size intelligent on-site gas flow standard device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115165043A (en) * | 2022-05-13 | 2022-10-11 | 北京市燃气集团有限责任公司 | System, method and device for monitoring gas volume metering error |
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2021
- 2021-09-06 CN CN202122136165.XU patent/CN215909939U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115165043A (en) * | 2022-05-13 | 2022-10-11 | 北京市燃气集团有限责任公司 | System, method and device for monitoring gas volume metering error |
| CN115165043B (en) * | 2022-05-13 | 2023-09-26 | 北京市燃气集团有限责任公司 | Monitoring system, method and device for gas volume metering error |
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