Gas meter real flow pressurized gas flow standard device and test method

Abstract

The present invention discloses a standard device for real-flow pressurized gas flow of a gas meter and a test method. The standard device for real-flow pressurized gas flow of a gas meter comprises a natural gas tank, a vacuum tank, a high-low temperature box, and a gas meter arranged in the high-low temperature box, a second heat exchanger arranged on the air inlet side and a first heat exchanger arranged on the exhaust side of the high-low temperature box, two standard container tank groups, one large and one small, and a servo power system arranged correspondingly thereto, and also comprises various connected pipelines and a plurality of gas valves, air inlet valves, air return valves, air valves and vacuum valves arranged in the pipelines for control. The device of the present invention can actively recover the natural gas used for testing into the original natural gas tank, and the air before the test can be emptied through the vacuum system and the gas distribution purge system, and the pure gas to be tested can be introduced. After the test, the residual gas will be sucked into the vacuum tank by the vacuum system to ensure the purity of the test gas and the thorough recovery of the test gas.

Description

[Technical field]

[0001] The present invention relates to the technical field of gas flow measurement, and in particular to a gas flow standard device and a test method for a real-flow pressurized gas flow in a gas meter. [Background technology]

[0002] Gas meters are important measuring tools for industrial and civil gas flow in my country. Their technical level and quality stability are the basic guarantee for the safety of people's lives and property, and are an indispensable part of the entire gas supply industry chain. From the perspective of market opportunities, with the continuous increase in the demand for industrial and civil gas in my country, the demand for gas meters is gradually increasing. The huge market space is a great boost to the development of the gas meter industry.

[0003] From a structural point of view, it mainly includes the first generation of gas meter membrane meter (mechanical type) and the second generation of ultrasonic gas meter (non-mechanical type). In addition, the replacement of gas meter products (generally, the replacement time of gas meters is 6-10 years) will inevitably promote the market demand for gas meters, as well as the gas market's demand for the installation and replacement of related gas meter products. This demand will inevitably drive the upgrading of the gas meter industry and promote the continuous upgrading and replacement of gas meter technology.

[0004] With the adjustment of energy structure, the development and application of global natural gas energy has entered a period of rapid development, the urban gasification rate will be higher and higher, and gas meters will have a bright future in the future domestic and foreign markets. In the research and development, production, calibration, testing and other links, higher requirements are put forward for standard devices. At present, the mainstream gas flow standard devices have certain advantages, but obviously there are more defects.

[0005] At present, most of the gas meter industry in my country is still dominated by diaphragm meters, which have mature production and testing technology and very complete national standard calibration specifications and other technical standard documents. At the same time, they have low prices that are acceptable to customers and users. However, with the change in the structure of urban gas consumption, problems such as wide range, low lower limit, and bulky and heavy volume are increasingly valued by manufacturers.

[0006] The emergence of ultrasonic gas meters has solved some of the problems of diaphragm gas meters to some extent, such as small size, narrow range, and no moving parts. At the same time, the fields of production process and technology, performance testing equipment and technology, and value transfer standard devices are still in the early stages. After early technical exchanges and a lot of research, it was found that meter manufacturers and testing institutions did not have a set of advanced gas flow standard devices in the process of ultrasonic R&D, production and calibration, which caused their products to be delayed in application and promotion. [Summary of the invention]

[0007] In view of this, in order to overcome the shortcomings of the prior art, the present invention provides a gas meter real flow pressurized gas flow standard device and test method, which is particularly suitable for ultrasonic gas meters. It adopts the volume method and has the functions of real gas circulation test, real gas collection, leakage alarm, etc. It can generate stable and standard different airflows, and can test the performance of ultrasonic gas meters at different temperatures and flow rates. It is an ideal equipment for ultrasonic gas meters to test the real gas and air high and low temperature performance, and can realize the recovery of gas, which is economical and environmentally friendly.

[0008] To achieve the above object, the technical solution of the present invention is as follows:

[0009] A gas meter real-flow pressurized gas flow standard device comprises a natural gas tank, a vacuum tank, a high-temperature and low-temperature box and a gas meter arranged in the high-temperature and low-temperature box, a second heat exchanger arranged on the air inlet side and a first heat exchanger arranged on the exhaust side of the high-temperature and low-temperature box, two standard container tank groups, one large and one small, and a servo power system arranged accordingly, and also comprises various connected pipelines and gas valves, air inlet valves, return valves, air valves and vacuum valves arranged in the pipelines for control.

[0010] The natural gas tank is connected to the two standard container tank groups, one large and one small, through a pipeline, and a gas valve is arranged in the pipeline; the same side of the two standard container tank groups, one large and one small, is connected to a second heat exchanger, the second heat exchanger is connected to one side of the high and low temperature box, the second heat exchanger is also connected to the external air through a pipeline, and an air valve is arranged in the pipeline; the vacuum tank is connected to the common end of the first heat exchanger and the high and low temperature box through a pipeline, and a vacuum valve is arranged in the pipeline.

[0011] The other side of the high and low temperature box is connected to the first heat exchanger, and the first heat exchanger is connected to the two standard container tank groups, one large and one small, through another pipeline to form a gas circulation loop.

[0012] Preferably, two gas valves are provided and located on the connecting pipeline of the natural gas tank; one air valve and one vacuum valve are provided each; and four groups of eight air inlet valves and air return valves are provided and installed in each connecting pipeline respectively.

[0013] Furthermore, the air inlet valve and the air return valve are respectively installed in the connecting pipelines of the two standard container tank groups, one large and one small, the two heat exchangers and the high and low temperature boxes. The air inlet valve and the air return valve are set in the connecting pipeline between the first heat exchanger and the high and low temperature box; the air inlet valve and the air return valve are respectively set in the connecting pipelines between the second heat exchanger and the two standard container tank groups, one large and one small.

[0014] Furthermore, the two standard container tanks, one large and one small, refer to a large standard container tank group and a small standard container tank group, which are divided into a large container tank of 100L and a small container tank of 10L. When the gas flow rate is within the range of 16 to 1000L / h, the small standard container tank group is activated, and when the gas flow rate range is 2 to 10m 3 / h enables large standard container tank groups.

[0015] Preferably, the large standard container tank group includes two 100L container tank cylinders symmetrically arranged on the left and right, a first servo power system is arranged in the middle, and an air intake valve and an air return valve are arranged in the external connecting pipeline of the 100L container tank cylinder for air intake or exhaust.

[0016] The small standard container tank group includes two 10L container tank cylinders that are symmetrically arranged on the left and right, a second servo power system is arranged in the middle, and an air intake valve and an air return valve are arranged in the external connecting pipeline of the 10L container tank cylinder for air intake or exhaust.

[0017] Preferably, two container tanks of the same standard are located on the same axis, a high-precision servo power system ensures movement accuracy, and active feeding facilitates the use of an innovative design method of synchronous suction and discharge.

[0018] The structure and operating principle of the second servo power system are the same as those of the first servo power system.

[0019] Furthermore, the servo power system includes a high-precision servo motor and two pistons. A piston is connected to each side of the high-precision servo motor. Each piston is arranged in the cylinder of the container tank on the corresponding side to form a double-cylinder active piston standard container tank.

[0020] Furthermore, the two sides of the high-precision servo motor are connected to the corresponding pistons through precision ball screws respectively, and an acquisition encoder is arranged at the bottom of the high-precision servo motor. A high-precision electronic grating ruler is arranged on the outside of the precision ball screw to ensure its movement accuracy. The high-precision pulse equivalent can achieve a linear length resolution of 10000P / L and 2000P / mm, which is far beyond the existing progress of 1000P / mm.

[0021] The above-mentioned various air intake valves, connecting pipelines and various functional devices constitute a fuel gas intake circuit, and the above-mentioned various air return valves, connecting pipelines and various functional devices constitute a fuel gas recovery circuit.

[0022] Preferably, a gas distribution and purge system is connected to the connecting pipeline of the natural gas tank, and the gas distribution and purge system includes a gas distribution and purge valve, a precision gas distributor and gas storage tanks respectively connected thereto, and the gas storage tanks include methane gas tanks, propane gas tanks and nitrogen gas tanks, or other required types of gas tanks.

[0023] The function of the gas distribution and purge system is: because it is difficult to exhaust the residual air in the device by only using the vacuum system extraction method, which affects the concentration of natural gas when it is injected. Therefore, after adding the gas distribution and purge system, an appropriate amount of methane, propane or nitrogen and other gases are introduced through a precision gas distributor to form a relatively close natural gas composition, so that the concentration of natural gas is higher and the test data is more accurate.

[0024] The device of the present invention can actively recover the natural gas used for testing into the original natural gas tank, and can exhaust the air before the test and introduce pure gas to be tested through the vacuum system and the gas distribution purge system; the residual gas after the test is sucked into the vacuum tank to ensure the purity of the test gas and the complete recovery of the test gas.

[0025] The present invention also relates to a method for testing a gas flow standard device for a real-flow pressurized gas flow of a gas meter, comprising the following steps:

[0026] (1) Setting the initial state, activating the large standard container tank group and the corresponding servo power system, the volume of the first container tank cylinder on one side is equal to 0, and the volume of the second container tank cylinder on the other side is 100L;

[0027] (2) Activate the gas distribution and purge system. The precision gas distribution instrument is configured according to the composition of the gas to be measured. Open the gas distribution and purge valve to exhaust the air. At the same time, open the vacuum system to suck out the purge gas.

[0028] (3) When all the residual purge gas enters the vacuum tank, open the gas valve and each air inlet valve, inject natural gas into each device, and when the pressure reaches the test pressure, close the gas valve on the natural gas tank connecting pipeline to prepare for entering the test state;

[0029] (4) When the air intake test begins, the corresponding servo power system is started, and the high-precision servo motor slowly drives the precision ball screw to make linear motion, while rotating and collecting the encoder output pulses to calculate the instantaneous flow rate;

[0030] (5) The host computer collects the output pulse signal of the standard device and the output signal of the gas meter under test in real time to perform real-time data analysis and high-speed calculation;

[0031] (6) After the above process is tested, close each air inlet valve and switch to the air return line, open each air return valve, and let the air return system start working;

[0032] (7) During the return air test, the high-precision servo motor is started to slowly drive the precision ball screw to make linear motion, while rotating and collecting the encoder output pulses to calculate the instantaneous flow rate;

[0033] (8) When the gas flow rate range is 16-1000L / h, the small standard container tank group and the corresponding servo power system are activated, and the test process is the same as above;

[0034] (9) After the gas meter under test completes the above-mentioned air intake and air return test process, the system automatically closes the above-mentioned air intake valve and air return valve;

[0035] (10) Start the vacuum tank device, open the air valve and the vacuum valve, quickly evacuate the residual gas in the gas meter, and automatically release the gas meter after the gas sensor installed in the pipeline detects safety.

[0036] The host computer in the above step (4) is an externally connected industrial computer or computer terminal, which performs calculations, analysis and comparison on the output signals of the gas meter under test and the standard device.

[0037] Furthermore, when all gas meters are tested and the intake gas needs to be recovered, the gas must be recovered into the second container tank of the large standard container tank group before the meter is removed;

[0038] Then close the return valve and the air inlet valve on the connecting pipeline of the cylinder of the second container tank, open the gas valve, and start the gas collection program. When the piston is pushed halfway, the cylinder of the first container tank forms a vacuum state, and then open the air valve to add air; continue to push the piston until all the gas in the cylinder of the first container tank is recovered, close the gas valve, open the vacuum valve to let all the gas enter the vacuum tank, and the entire gas collection process is completed.

[0039] The present invention is also applicable to real-flow pressure flow calibration tests on other gas meters, and is not limited to gas meters, but is also applicable to other gas tests. The test principle and structure are also protected within the scope of the description of the present invention.

[0040] The beneficial effects of the present invention are that the present invention adopts the volumetric method and has the functions of real gas circulation test, real gas collection, leakage alarm, etc., which can generate stable and standard different airflows, and can test the performance of ultrasonic gas meters at different temperatures and different flow rates. It is an ideal equipment for ultrasonic gas meter real gas and air high and low temperature performance testing, and can realize the recovery of gas, which is economical and environmentally friendly, and is worthy of promotion and application.

Brief Description of the Drawings

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0042] Figure 1 It is a schematic diagram of the structural principle of the present invention.

[0043] In the figure, 1, natural gas tank, 2, high and low temperature box, 3, gas meter, 4, vacuum tank, 5, large standard container tank group, 6, small standard container tank group, 7, high-precision servo motor, 71, acquisition encoder, 8, precision ball screw, 9, high-precision electronic grating ruler, 10, piston, 01, first heat exchanger, 02, second heat exchanger;

[0044] 001, gas valve, 002, gas valve, 11, air valve, 31, vacuum valve, 21, air intake valve, 22, air intake valve, 23, air intake valve, 24, air intake valve, 41, return air valve, 42, return air valve, 43, return air valve, return air valve 44; 51, gas distribution purge valve; 52, precision gas distribution instrument, 53, methane gas tank, 54, propane gas tank, 55, nitrogen gas tank, 56, spare gas tank. [Specific implementation method]

[0045] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] Example:

[0047] Reference Figure 1 , a gas meter real-flow pressurized gas flow standard device, comprising a natural gas tank 1, a vacuum tank 4, a high and low temperature box 2 and a gas meter 3 arranged in the high and low temperature box 2, a second heat exchanger 02 arranged on the air inlet side and a first heat exchanger 01 on the exhaust side of the high and low temperature box 2, respectively, a large standard container tank group 5, a small standard container tank group 6 and a servo power system arranged accordingly, various connecting pipelines and gas valves 001, gas valves 002, air valves 11, vacuum valves 31, intake valves 21, intake valves 22, intake valves 23, intake valves 24, return valves 41, return valves 42, return valves 43 and return valves 44 arranged in the pipelines for control.

[0048] The natural gas tank 1 is connected to the large standard container tank group 5 and the small standard container tank group 6 through pipelines, and a gas valve 001 and a gas valve 002 are set in the pipelines. The same side of the large standard container tank group 5 and the small standard container tank group 6 is connected to the second heat exchanger 02, and an air intake valve 22 is set in the connecting pipeline; the second heat exchanger 02 is connected to one side of the high and low temperature box 2, and the second heat exchanger 02 is also connected to the external air through a pipeline, and an air valve 11 is set in the pipeline. The vacuum tank 4 is connected to the common end of the first heat exchanger 01 and the high and low temperature box 2 through a pipeline, and a vacuum valve 31 is set in the pipeline.

[0049] The other side of the high and low temperature box 3 is connected to the first heat exchanger 01, and an air inlet valve 23 and an air return valve 43 are arranged in the connecting pipeline. The first heat exchanger 01 is connected to the large standard container tank group 5 and the small standard container tank group 6 through another pipeline to form a gas circulation loop.

[0050] The above-mentioned intake valve 21, intake valve 22, intake valve 23, intake valve 24 and connecting pipelines and various functional devices constitute a fuel gas intake circuit, and the return valve 41, return valve 42, return valve 43 and return valve 44 and connecting pipelines and various functional devices constitute a fuel gas recovery circuit.

[0051] Preferably, a gas distribution and purge system is also connected to the connecting pipeline of the natural gas tank 1, and the gas distribution and purge system includes a gas distribution and purge valve 51, a precision gas distributor 52 and gas storage tanks respectively connected thereto, and the gas storage tanks include a methane gas tank 53, a propane gas tank 54, a nitrogen gas tank 55 and a spare gas tank 56, and the spare gas tank is used to store other required types of gas.

[0052] The function of the gas distribution and purge system is: because it is difficult to exhaust the residual air in the device by only using the vacuum system extraction method, which affects the concentration of natural gas when it is injected. Therefore, after adding the gas distribution and purge system, an appropriate amount of methane, propane or nitrogen and other gases are introduced through the precision gas distribution instrument 52 to form a relatively close natural gas composition, so that the purity of the natural gas in the device is higher and the test data is more accurate.

[0053] The large standard container tank group 5 includes two 100L container tank cylinders A and B that are symmetrically arranged on the left and right, with a first servo power system arranged in the middle, and an intake valve 24 and a return valve 41 arranged in the external connecting pipeline of cylinder A, and an intake valve 21 and a return valve 44 arranged in the external connecting pipeline of cylinder B, which are respectively used to control the intake or exhaust.

[0054] The first servo power system includes a high-precision servo motor 7 and two pistons 10. A piston 10 is connected to each side of the high-precision servo motor 7. The two pistons 10 are arranged in cylinders A and B of the container tank on the corresponding sides to form a double-cylinder active piston standard container tank.

[0055] The two sides of the high-precision servo motor 7 are connected to the corresponding pistons 10 through precision ball screws 8 respectively. An acquisition encoder 71 is arranged at the bottom of the high-precision servo motor 7, and a high-precision electronic grating ruler 9 is arranged on the outside of the precision ball screw 8 to ensure its movement accuracy. The high-precision pulse equivalent can achieve a linear length resolution of 10000P / L and 2000P / mm, which far exceeds the existing progress of 1000P / mm.

[0056] The small standard container tank group includes two 10L container tank cylinders C and D that are symmetrically arranged on the left and right, with a second servo power system arranged in the middle, and an intake valve and a return valve are also arranged in the external connecting pipelines of the C and D cylinders, which are used to control the intake or exhaust respectively.

[0057] The structure and operating principle of the second servo power system are the same as those of the first servo power system.

[0058] The two standard container tank cylinders are located on the same axis. A high-precision servo power system ensures movement accuracy, and active feeding facilitates the innovative design method of synchronous suction and discharge.

[0059] The present invention also relates to a method for testing a gas flow standard device for a real-flow pressurized gas flow of a gas meter, comprising the following steps:

[0060] (1) Setting the initial state, activating the large standard container tank group 5 and the corresponding servo power system, so that the volume of the container tank cylinder body A on one side is equal to 0, and the volume of the container tank cylinder body B on the other side is 100L;

[0061] (2) Activate the gas distribution and purge system. The precision gas distribution instrument 52 is configured according to the composition of the gas to be measured. The gas distribution and purge valve 51 is opened to exhaust air. At the same time, the vacuum system is opened to suck out the purge gas.

[0062] (3) When setting the initial state, first open the gas valve 001 and the gas valve 002 and the return valve 41, return valve 42 and vacuum valve 31 on the connecting pipeline of cylinder A of the large standard container tank group 5, and put natural gas into the tank body of cylinder B. At this time, the corresponding servo control system starts to move to the tank body of cylinder A on the other side. The tank body space of cylinder B is getting bigger and bigger, and more and more natural gas is entering. At the same time, the tank body space of cylinder A on the other side is getting smaller and smaller, and the excess gas is discharged and recovered by the vacuum system. When the volume of cylinder B reaches 100L, the volume of cylinder A is 0.

[0063] When all the residual purge gas enters the vacuum tank 4, open the air inlet valve 21, the air inlet valve 22, the air inlet valve 23, and the air inlet valve 24 to inject natural gas into each device. When the pressure reaches the test pressure, close the gas valve 001 and the gas valve 002 on the connecting pipeline of the natural gas tank 1 to prepare for entering the test state;

[0064] (4) When the air intake test begins, the corresponding servo power system is started, and the high-precision servo motor 7 slowly drives the precision ball screw 8 to make linear motion, while rotating and collecting the encoder output pulses to calculate the instantaneous flow rate;

[0065] (5) The host computer collects the output pulse signal of the standard device and the output signal of the gas meter under test in real time to perform real-time data analysis and high-speed calculation;

[0066] (6) After the above process is tested, close the air inlet valve 21, the air inlet valve 22, the air inlet valve 23, and the air inlet valve 24, switch to the air return line, open the air return valve 41, the air return valve 42, the air return valve 43, and the air return valve 44, and let the air return system start working;

[0067] (7) During the return air test, the high-precision servo motor 7 is started to slowly drive the precision ball screw 8 to make linear motion, while rotating and collecting the encoder output pulses to calculate the instantaneous flow rate;

[0068] (8) When the gas flow rate ranges from 16 to 1000 L / h, the small standard container tank group 6 and the corresponding servo power system are activated, and the test process is the same as above;

[0069] (9) After the gas meter under inspection completes the above-mentioned air intake and air return test process, the system automatically closes the above-mentioned air intake valve 22, air intake valve 23 and air return valve 42, air return valve 43;

[0070] (10) Start the vacuum tank 4 device, open the air valve 11 and the vacuum valve 31, quickly evacuate the residual gas in the gas meter, and automatically release the gas meter after the gas sensor installed in the pipeline detects safety.

[0071] Furthermore, when all gas meters are tested and the intake gas needs to be recovered, the gas must be recovered into the container tank cylinder body B of the large standard container tank group 5 before the meter is removed.

[0072] Then close the return valve 44 and the air inlet valve 21, open the gas valve 001 and the gas valve 002, and start the gas collection program. When the piston is pushed halfway, the cylinder of container tank A forms a vacuum state, and then open the air valve 11 to add air; then continue to push the piston until all the gas in the cylinder of container tank A is recovered, close the gas valve 01, open the vacuum valve 31 to let all the gas enter the vacuum tank 4, and the entire gas collection process is completed.

[0073] The device of the present invention can actively recycle the natural gas used for testing into the original natural gas tank 1, and can exhaust the air before testing through the vacuum system and the gas distribution purge system, and introduce pure gas to be tested. The residual gas after the test will be sucked into the vacuum tank 4 by the vacuum system, ensuring the purity of the test gas and the complete recovery of the test gas.

[0074] The present invention adopts the standard volume method, and can provide operating flow and standard flow through the temperature and pressure acquisition compensation function. It also has functions such as real gas circulation test, real gas collection, and leakage alarm. It can achieve a system working pressure of 4Bar and output different real flow gas standard flow values ​​at the same time. The flow range is 10 to 10000L / h, and the high and low temperature test environment is -25℃ to 60℃.

[0075] The present invention is also applicable to real flow and pressure flow calibration tests on other gas meters, and is not limited to gas meters, but is also applicable to other gas tests. The test principle and structure are also protected within the scope of the description of the present invention.

[0076] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A gas meter real flow pressurized gas flow standard device, characterized in that: It includes a natural gas tank, a vacuum tank, a high and low temperature box and a gas meter arranged in the high and low temperature box, a second heat exchanger arranged on the air inlet side and a first heat exchanger arranged on the exhaust side of the high and low temperature box, two standard container tank groups, one large and one small, and a servo power system arranged accordingly, and also includes various connected pipelines and gas valves, air inlet valves, air return valves, air valves and vacuum valves arranged in the pipelines for control; The natural gas tank is connected to the two standard container tanks, one large and one small, through a pipeline, and the gas valve is arranged in the pipeline; the same side of the two standard container tanks is connected to the second heat exchanger, the second heat exchanger is connected to one side of the high and low temperature box, the second heat exchanger is also connected to the external air through a pipeline, and the air valve is arranged in the pipeline; the vacuum tank is connected to the common end of the first heat exchanger and the high and low temperature box through a pipeline, and the vacuum valve is arranged in the pipeline; The other side of the high and low temperature box is connected to a first heat exchanger, and the first heat exchanger is connected to the two standard container tanks, one large and one small, through another pipeline to form a gas circulation loop; The air inlet valve and the air return valve are respectively installed in the connecting pipelines of the two standard container tanks, one large and one small, the two heat exchangers and the high and low temperature boxes; The servo power system includes a high-precision servo motor and two pistons. A piston is connected to each side of the high-precision servo motor. Each piston is arranged in the cylinder of the container tank on the corresponding side to form a double-cylinder active piston standard container tank. The two sides of the high-precision servo motor are respectively connected to the corresponding pistons through precision ball screws, an acquisition encoder is arranged at the bottom of the high-precision servo motor, and a high-precision electronic grating ruler is arranged on the outer side of the precision ball screw; The connecting pipeline of the natural gas tank is connected to a gas distribution and purge system, which includes a gas distribution and purge valve, a precision gas distribution instrument and gas storage tanks respectively connected thereto, and the gas storage tanks include a methane gas tank, a propane gas tank and a nitrogen gas tank.

2. The gas meter real flow pressurized gas flow standard device according to claim 1, characterized in that: The two standard container tank groups, one large and one small, refer to a large standard container tank group and a small standard container tank group, which are divided into a large container tank of 100L and a small container tank of 10L. The small standard container tank group is activated when the gas flow rate is in the range of 16 to 1000L / h, and the large standard container tank group is activated when the gas flow rate is in the range of 2 to 10m³ / h.

3. The real-flow pressurized gas flow standard device for a gas meter according to claim 2, characterized in that: The large standard container tank group includes two 100L container tank cylinders that are symmetrically arranged on the left and right, and a first servo power system is arranged in the middle.

4. The real-flow pressurized gas flow standard device for a gas meter according to claim 2, characterized in that: The small standard container tank set comprises two 10L container tank cylinders which are symmetrically arranged on the left and right, and a second servo power system is arranged in the middle.

5. The test method of the gas meter real flow pressurized gas flow standard device according to any one of claims 1 to 4, characterized in that: The following steps are involved: (1) Set the initial state, enable the large standard container tank group and the corresponding servo power system, the volume of the first container tank cylinder on one side is equal to 0, and the volume of the second container tank cylinder on the other side is 100L; (2) Activate the gas distribution and purge system. The precision gas distribution instrument is configured according to the composition of the gas to be measured. Open the gas distribution and purge valve to exhaust the air. At the same time, open the vacuum system to suck out the purge gas. (3) When all the residual purge gas enters the vacuum tank, open the gas valve and each air inlet valve, inject natural gas into each device, and when the pressure reaches the test pressure, close the gas valve on the natural gas tank connecting pipeline to prepare for entering the test state; (4) When the air intake test begins, the corresponding servo power system is started, and the high-precision servo motor slowly drives the precision ball screw to make linear motion, while rotating and collecting the encoder output pulses to calculate the instantaneous flow rate; (5) The host computer collects the output pulse signal of the standard device and the output signal of the gas meter under test in real time to perform real-time data analysis and high-speed calculation; (6) After the above steps are tested, close each air inlet valve and switch to the air return line, open each air return valve, and let the air return system start working; (7) During the return air test, the high-precision servo motor is started to slowly drive the precision ball screw to make linear motion, while rotating and collecting the encoder output pulses to calculate the instantaneous flow rate; (8) When the gas flow rate range is 16-1000L / h, the small standard container tank group and the corresponding servo power system are activated, and the test process is the same as above; (9) After the gas meter under test completes the above-mentioned air intake and return air test process, the system automatically closes the above-mentioned air intake valve and return air valve; (10) Start the vacuum tank device, open the air valve and the vacuum valve, quickly evacuate the residual gas in the gas meter, and automatically release the gas meter after the gas sensor installed in the pipeline detects safety.

6. The test method of the gas meter real flow pressurized gas flow standard device according to claim 5 is characterized in that: When all gas meters are tested and the gas needs to be recovered, the gas must be recovered into the second container tank of the large standard container tank group before the meter is removed; Then close the return valve and the air inlet valve on the connecting pipeline of the cylinder of the second container tank, open the gas valve, and start the gas collection program. When the piston is pushed halfway, the cylinder of the first container tank forms a vacuum state, and then open the air valve to add air; continue to push the piston until all the gas in the cylinder of the first container tank is recovered, close the gas valve, open the vacuum valve to let all the gas enter the vacuum tank, and the entire gas collection process is completed.

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