CN211913378U - Secondary dynamic gas distribution device and system based on gas mass flow control - Google Patents
Secondary dynamic gas distribution device and system based on gas mass flow control Download PDFInfo
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- CN211913378U CN211913378U CN202020355886.2U CN202020355886U CN211913378U CN 211913378 U CN211913378 U CN 211913378U CN 202020355886 U CN202020355886 U CN 202020355886U CN 211913378 U CN211913378 U CN 211913378U
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Abstract
The utility model relates to a secondary developments distributing device and system based on gas mass flow control is applied to distribution technical field, and wherein, secondary developments distributing device based on gas mass flow control includes: the device comprises a dilution gas storage tank, a diluted gas storage tank, a primary distribution gas tank and a secondary distribution gas tank, wherein a gas outlet of the dilution gas storage tank is connected with a first gas inlet of the primary distribution gas tank through a first gas transmission pipeline, and is connected with a first gas inlet of the secondary distribution gas tank through a second gas transmission pipeline; the gas outlet of the diluted gas storage tank is connected with the second gas inlet of the primary gas distribution tank through a third gas transmission pipeline; a first air outlet of the primary distribution air tank is connected with a second air inlet of the secondary distribution air tank through a fourth air transmission pipeline; a pressure monitoring unit is also arranged in the primary air distribution tank; and the first gas transmission pipeline, the second gas transmission pipeline, the third gas transmission pipeline and the fourth gas transmission pipeline are all provided with a gas control unit.
Description
Technical Field
The utility model relates to a distribution technical field, concretely relates to secondary developments distributing device and system based on gas mass flow control.
Background
The dynamic gas distribution method is to continuously mix the gas with known components and the diluent gas according to a certain flow ratio to meet the requirement of configuring the gas with different concentrations, and can realize quick response and recovery during the test of the gas sensor to obtain an accurate measurement result. Gas distribution units are also being developed to obtain gases of desired concentrations.
In the existing gas distribution unit, a gas flow controller is often adopted to precisely control the gas flow, and then the process gas and the background gas are mixed and directly output at the position of a rear-end gas outlet. However, since the gas flow controller has a certain range, the lowest controllable flow rate changes according to the difference of the full range, if a lower gas concentration is required, the gas flow controller with a smaller range is selected, and the output of the process gas is also reduced, so that the output of the mixed gas is less, and if the flow rate of the output gas is increased, the gas analyzer may be damaged; if a gas flow controller with a large range is selected, the flow of gas distribution output cannot be reduced, and low-concentration gas cannot be distributed, so that the use of a gas distribution device is limited.
SUMMERY OF THE UTILITY MODEL
In view of this, the present invention provides a secondary dynamic gas distribution device and system based on gas mass flow control, which overcome the problems in the related art at least to some extent.
In order to solve the technical problem, the utility model adopts the following technical scheme:
in a first aspect, a secondary dynamic gas distribution device based on gas mass flow control comprises:
a diluted gas storage tank, a primary distribution gas tank and a secondary distribution gas tank, wherein,
the gas outlet of the dilution gas storage tank is connected with the first gas inlet of the primary gas distribution tank through a first gas transmission pipeline, and is connected with the first gas inlet of the secondary gas distribution tank through a second gas transmission pipeline;
the gas outlet of the diluted gas storage tank is connected with the second gas inlet of the primary gas distribution tank through a third gas transmission pipeline;
a first air outlet of the primary distribution air tank is connected with a second air inlet of the secondary distribution air tank through a fourth air transmission pipeline;
a pressure monitoring unit is also arranged in the primary air distribution tank;
and the first gas transmission pipeline, the second gas transmission pipeline, the third gas transmission pipeline and the fourth gas transmission pipeline are all provided with a gas control unit.
Optionally, the second air outlet of the primary distribution air tank is connected with the third air inlet of the secondary distribution air tank through a fifth air transmission pipeline, and a stop valve is arranged on the fifth air transmission pipeline.
Optionally, the third gas outlet of the primary distribution gas tank further discharges gas through a sixth gas transmission pipeline, and the sixth gas transmission pipeline is provided with a stop valve.
Optionally, the gas outlet of the secondary distribution gas tank further discharges gas through a seventh gas transmission pipeline, and the seventh gas transmission pipeline is provided with a stop valve.
Optionally, the gas control unit comprises a shut-off valve and a gas mass flow controller.
Optionally, the pressure monitoring unit includes a pressure sensor and an electronic control unit.
In a second aspect, a secondary dynamic gas distribution system based on gas mass flow control comprises: the upper computer is connected with the secondary dynamic gas distribution device based on gas mass flow control through a communication line so as to carry out logic control on the secondary dynamic gas distribution device based on gas mass flow control.
Optionally, the gas distribution device further comprises a housing, and the secondary dynamic gas distribution device based on gas mass flow control is arranged inside the housing.
Optionally, the method further includes: and the human-computer interaction unit is connected with the upper computer.
Optionally, the upper computer may be a PC or a touch screen.
The utility model adopts the above technical scheme, can realize following technological effect: in the application, the dilution gas storage tank, the diluted gas storage tank, the primary distribution gas tank and the secondary distribution gas tank are arranged, wherein a gas outlet of the dilution gas storage tank is connected with a first gas inlet of the primary distribution gas tank through a first gas transmission pipeline, and is connected with a first gas inlet of the secondary distribution gas tank through a second gas transmission pipeline; the gas outlet of the diluted gas storage tank is connected with the second gas inlet of the primary gas distribution tank through a third gas transmission pipeline; a first air outlet of the primary distribution air tank is connected with a second air inlet of the secondary distribution air tank through a fourth air transmission pipeline; a pressure monitoring unit is also arranged in the primary air distribution tank; and the first gas transmission pipeline, the second gas transmission pipeline, the third gas transmission pipeline and the fourth gas transmission pipeline are all provided with a gas control unit. Through setting up primary distribution gas jar and second grade distribution gas jar, make the gas in dilution gas holder and the diluted gas holder, mix in the primary distribution gas jar at first, if the concentration of the mist that obtains is still very high, then with dilution gas and mist common input to the second grade distribution gas jar in, mix again, thereby further reduce the concentration by dilution gas, so, will be followed by dilution gas and pass through the gas control unit in the diluted gas holder, the flow of control gas, then further dilute through the secondary distribution gas jar again, so, when wanting to join in marriage the gas concentration who gets lower concentration, can select the great gas control unit of range, carry out the secondary dilution to gas, increase the output of distribution, and can not damage the device.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
FIG. 1 is a schematic diagram of a prior art gas distribution apparatus;
fig. 2 is a schematic structural diagram of a secondary dynamic gas distribution device based on gas mass flow control according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of a secondary dynamic gas distribution device based on gas mass flow control according to another embodiment of the present invention;
fig. 4 is a schematic structural diagram of a secondary dynamic gas distribution system based on gas mass flow control according to an embodiment of the present invention;
reference numerals:
the device comprises a diluent gas storage tank-1, a diluted gas storage tank-2, a primary gas distribution tank-3, a secondary gas distribution tank-4, a pressure monitoring unit-5, a gas control unit-6, a stop valve-7, a gas mass flow controller-8, a secondary dynamic gas distribution device-9 based on gas mass flow control, an upper computer-10 and a human-computer interaction device-11.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below. It is to be understood that the embodiments described are only some embodiments of the invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
For a better understanding of the solution provided by the present application, the following needs to be understood:
the measurement ranges of the common experimental-grade high-precision gas mass flow controllers on the market at present are generally 5SCCM at the lowest and 30SLM at the highest, the measurement range is small and used for controlling process gas, and the measurement range is large and used for controlling background gas. The total flow output by gas distribution is generally determined by customer processes, with the development of national scientific research in recent years, the required concentration is lower and lower, but at the same time, the required total flow of gas output is lower and lower, so that the required concentration of gas distribution cannot be achieved by direct gas distribution for one time under many working conditions (the MFC with the smallest measuring range is 5sccm, the price is doubled, the measuring range is 2000SLM (maximum measuring range), the price is doubled, and the precision is low and the response is slow in the market), if a gas flow controller with the large measuring range is adopted, the flow output by gas distribution cannot be reduced, and the embarrassing situation of gas distribution for one time is caused.
The method is characterized in that the method is calculated by two full-range gas controllers (a large range is used for background gas and a small range is used for process gas control on the premise of equal volume precision response time and other parameters) commonly used in the market at present, the full-range of 5SCCM can be controlled to be 0.1SCCM at the lowest, so that the concentration of 5 x 0.02/30000 which is about 3PPM (PPM, 1/1000000) can be obtained by calculating the difference of the two maximum flows, but the output gas flow is 30SLM +5SCCM which is far beyond the flow range which can be accepted by a common gas analysis instrument and is only about 1SLM (1000SCCM), and the analysis instrument can be damaged due to the excessive flow.
Fig. 1 is a schematic structural diagram of a gas distribution apparatus in the prior art, and referring to fig. 1, a gas distribution unit in the prior art performs gas distribution only once, that is, gas in a dilution gas storage tank and gas in a diluted gas storage tank are both input into a gas distribution tank, and the gas in the dilution gas storage tank and the gas in the diluted gas storage tank are mixed and then output, but this method has disadvantages that, for example, a user needs to dynamically output a 1PPM concentration gas flow rate of 1SLM, and if the maximum flow rate output is taken as a limit, the minimum concentration that the existing gas distribution unit can output is 0.1SCCM/1000SCCM which is 100 PPM; if 1PPM is taken as the limit, then the maximum output traffic needs to reach 100 SLM. Therefore, this direct gas distribution method cannot meet the customer requirements.
Examples
Fig. 2 is a schematic structural diagram of a secondary dynamic gas distribution device based on gas mass flow control according to an embodiment of the present invention. As shown in fig. 2, the present embodiment provides a secondary dynamic gas distribution apparatus based on gas mass flow control, including:
a diluent gas storage tank 1, a diluted gas storage tank 2, a primary distribution tank 3 and a secondary distribution tank 4, wherein,
the gas outlet of the dilution gas storage tank is connected with the first gas inlet of the primary gas distribution tank through a first gas transmission pipeline, and is connected with the first gas inlet of the secondary gas distribution tank through a second gas transmission pipeline;
the gas outlet of the diluted gas storage tank is connected with the second gas inlet of the primary gas distribution tank through a third gas transmission pipeline;
a first air outlet of the primary distribution air tank is connected with a second air inlet of the secondary distribution air tank through a fourth air transmission pipeline;
a pressure monitoring unit 5 is also arranged in the primary air distribution tank;
and the first gas transmission pipeline, the second gas transmission pipeline, the third gas transmission pipeline and the fourth gas transmission pipeline are all provided with a gas control unit 6.
In this implementation, through setting up primary distribution gas jar and second grade distribution gas jar, make the gas in dilution gas holder and the diluted gas holder, mix in primary distribution gas jar at first, if the concentration of the mist that obtains is still very high, then with dilution gas and mist common input to second grade distribution gas jar again, mix once more, thereby further reduce the concentration by dilution gas, so, to be followed by dilution gas and pass through the gas control unit in the diluted gas holder, the flow of control gas, then further dilute through secondary distribution gas jar again, so, when wanting to join in marriage the gas concentration of low concentration, can select the great gas control unit of range, carry out the secondary dilution to gas, increase the output of distribution.
In some embodiments, the gas control unit comprises a shut-off valve 7 and a gas mass flow controller 8, wherein the range of the gas mass flow controller can be selectively set according to the actual process requirements.
Optionally, the second air outlet of the primary distribution air tank is connected with the third air inlet of the secondary distribution air tank through a fifth air transmission pipeline, and a stop valve is arranged on the fifth air transmission pipeline.
Optionally, the third gas outlet of the primary distribution gas tank further discharges gas through a sixth gas transmission pipeline, and the sixth gas transmission pipeline is provided with a stop valve.
Optionally, the gas outlet of the secondary distribution gas tank further discharges gas through a seventh gas transmission pipeline, and the seventh gas transmission pipeline is provided with a stop valve.
Specifically, fig. 3 is a structural schematic diagram of a secondary dynamic gas distribution device based on gas mass flow control that another embodiment of the utility model provides, refer to fig. 3, stop valve and gas mass flow controller on the first gas pipeline are marked as V1, MFC1, stop valve and gas mass flow controller on the second gas pipeline are marked as V3, MFC3, stop valve and gas mass flow controller on the third gas pipeline are marked as V2, MFC2, stop valve and gas mass flow controller on the fourth gas pipeline are marked as V4, MFC4, stop valve on the fifth gas pipeline is marked as V5, stop valve on the sixth gas pipeline is marked as V6, stop valve on the seventh gas pipeline is marked as V7.
The secondary dynamic gas distribution device based on gas mass flow control in fig. 3 has MFC1 and MFC3 full range of 10SLM, MFC2 and MFC4 full range of 5 SCCM.
MFC1 controls 1000SCCM, MFC2 controls 1SCCM, so concentration gas in the primary gas tank is 1000PPM, use MFC3 to let in background gas 1000SCCM and dilute, MFC4 controls low concentration initial mixed gas of 1SCCM in the secondary gas tank, has diluted 1000 times again, and the concentration that outputs becomes 1PPM concentration in the final V7 department, and the total flow is 1 SLM.
If MFC1 controls 10000SCCM, MFC2 controls 0.1SCCM, the primary gas concentration is 10PPM, then use MFC3 to inject the background gas 1000SCCM to dilute, and MFC4 controls the low-concentration initial mixed gas of 0.1SCCM output in the primary gas distribution tank, and has diluted 10000 times, the concentration of the output at V7 becomes 1PPB concentration finally, the total flow is 1 SLM.
If the output with higher concentration is required to be realized, the concentration output of 1/40(5SCCM/10000SCCM 0.02) can be output at the highest energy, then V4 is closed, V5 is opened, and the primary gas tank is used alone to realize the high-concentration output.
It can be understood that the flow regulation is dynamically realized according to the requirements of customers, can be changed in real time, and does not need to change an air source.
In some embodiments, the pressure monitoring unit includes a pressure sensor and an electronic control unit.
In this application, in order to realize secondary distribution, need the pressure balance function of adding in the part of primary distribution jar when primary distribution.
Because the use requirement of the gas mass flow controller is that a certain working pressure difference is generally between 0.1MPa and 0.5MPa (gauge pressure), if the equipment is directly connected with the gas circuit and cannot work normally, the MFC4 can not work stably due to the constant fluctuation of the pressure difference.
Therefore, a set of pressure balance system is needed, and hardware is mainly realized by a high-precision pressure sensor in the primary gas distribution tank and an electric control system (a PLC or a special acquisition module). The method is that the pressure in the primary gas distribution tank is maintained at about 0.25MPa, and the pressure at the inlet of the device is set to be 0.5MPa, so that the working pressure difference range of the primary MFC1MFC2 is met, and the control pressure difference range of the secondary gas mixing MFC4 is met. The method for maintaining the primary gas distribution tank utilizes the PID function of a PLC or a special acquisition module, takes 0.25MPa as the input value of a PID system, takes the output value as the set values of the MFC1 and the MFC2, increases or decreases the set values of the two MFCs simultaneously according to the proportion required by the primary gas distribution, achieves the aim of unchanging real-time proportion, and finally stabilizes the pressure of the primary gas distribution tank to about 0.25 MPa. The formula used by the PID part in the PLC or the special acquisition module is as follows:
the basic implementation formula of the PID is as follows:
u(t)＝Kp*e(t)+Ki∑e(t)+Kd[e(t)–e(t-1)]+u0
where e (t) represents a deviation between the target pressure value and the actually detected pressure value, u (t) represents an output adjustment amount, u0 represents a target value, and Kp Ki Kd is a PID parameter.
Fig. 4 is a schematic structural diagram of a secondary dynamic gas distribution system based on gas mass flow control according to an embodiment of the present invention. As shown in fig. 4, the present embodiment provides a secondary dynamic gas distribution system based on gas mass flow control, including: the upper computer 10 is connected with the secondary dynamic gas distribution device based on the gas mass flow control through a communication line so as to perform logic control on the secondary dynamic gas distribution device based on the gas mass flow control, and the secondary dynamic gas distribution device based on the gas mass flow control 9 is provided according to the embodiment.
Optionally, the method further includes: and the man-machine interaction device 11 is connected with the upper computer.
Optionally, the upper computer may be a PC or a touch screen.
The upper computer of the software of the system can be connected with equipment for logic control by using a PC through 232/485 or USB-to-232/485 communication, and can also be controlled by using a human-computer interaction device on the equipment, and the human-computer interaction device is also communicated with an acquisition unit of the whole system through 485 communication, so that the upper computer can select the PC or a touch screen.
It can be understood that the stop valve, the gas mass flow controller, the pressure sensor and the electronic control unit in the secondary dynamic gas distribution device based on gas mass flow control are all connected with an upper computer so as to control the devices through the upper computer.
In some embodiments, the secondary dynamic gas distribution system based on gas mass flow control further comprises a housing, and the secondary dynamic gas distribution device based on gas mass flow control is arranged inside the housing.
Through setting up the casing, can protect devices such as inside gas holder of system, distribution jar to can conveniently remove.
It is understood that the same or similar parts in the above embodiments may be mutually referred to, and the same or similar parts in other embodiments may be referred to for the content which is not described in detail in some embodiments.
It should be noted that, in the description of the present invention, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In addition, in the description of the present invention, "a plurality" means at least two unless otherwise specified.
Any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps of the process, and the scope of the preferred embodiments of the present invention includes other implementations in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the embodiments of the present invention.
It should be understood that portions of the present invention may be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the various steps or methods may be implemented in software or firmware stored in memory and executed by suitable instruction execution devices. For example, if implemented in hardware, as in another embodiment, any one or combination of the following techniques, which are known in the art, may be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application specific integrated circuit having an appropriate combinational logic gate circuit, a Programmable Gate Array (PGA), a Field Programmable Gate Array (FPGA), or the like.
It will be understood by those skilled in the art that all or part of the steps carried by the method for implementing the above embodiments may be implemented by hardware related to instructions of a program, which may be stored in a computer readable storage medium, and when the program is executed, the program includes one or a combination of the steps of the method embodiments.
In addition, each functional unit in the embodiments of the present invention may be integrated into one processing module, or each unit may exist alone physically, or two or more units are integrated into one module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. The integrated module, if implemented in the form of a software functional module and sold or used as a stand-alone product, may also be stored in a computer readable storage medium.
The storage medium mentioned above may be a read-only memory, a magnetic or optical disk, etc.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
Although embodiments of the present invention have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art without departing from the scope of the present invention.
Claims (10)
1. A secondary dynamic gas distribution device based on gas mass flow control is characterized by comprising:
a diluted gas storage tank, a primary distribution gas tank and a secondary distribution gas tank, wherein,
the gas outlet of the dilution gas storage tank is connected with the first gas inlet of the primary gas distribution tank through a first gas transmission pipeline, and is connected with the first gas inlet of the secondary gas distribution tank through a second gas transmission pipeline;
the gas outlet of the diluted gas storage tank is connected with the second gas inlet of the primary gas distribution tank through a third gas transmission pipeline;
a first air outlet of the primary distribution air tank is connected with a second air inlet of the secondary distribution air tank through a fourth air transmission pipeline;
a pressure monitoring unit is also arranged in the primary air distribution tank;
and the first gas transmission pipeline, the second gas transmission pipeline, the third gas transmission pipeline and the fourth gas transmission pipeline are all provided with a gas control unit.
2. The device as claimed in claim 1, wherein the second air outlet of the primary air distribution tank is connected with the third air inlet of the secondary air distribution tank through a fifth air transmission pipeline, and a stop valve is arranged on the fifth air transmission pipeline.
3. The device of claim 1, wherein the third gas outlet of the primary gas distribution tank also discharges gas through a sixth gas transmission pipeline, and a stop valve is arranged on the sixth gas transmission pipeline.
4. The device as claimed in claim 1, wherein the gas outlet of the secondary gas distribution tank also discharges gas through a seventh gas transmission pipeline, and a stop valve is arranged on the seventh gas transmission pipeline.
5. The apparatus of claim 1, wherein the gas control unit comprises a shut-off valve and a gas mass flow controller.
6. The device of claim 1, wherein the pressure monitoring unit comprises a pressure sensor and an electronic control unit.
7. A secondary dynamic gas distribution system based on gas mass flow control is characterized by comprising: the secondary dynamic gas distribution device based on the gas mass flow control as claimed in any one of claims 1 to 6, and the upper computer is connected with the secondary dynamic gas distribution device based on the gas mass flow control through a communication line so as to carry out logic control on the secondary dynamic gas distribution device based on the gas mass flow control.
8. The system of claim 7, further comprising a housing, the gas mass flow control based secondary dynamic gas distribution device being disposed inside the housing.
9. The system of claim 7, further comprising: and the human-computer interaction unit is connected with the upper computer.
10. The system of claim 7, wherein the upper computer is a PC or a touch screen.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115212738A (en) * | 2022-06-29 | 2022-10-21 | 广西电网有限责任公司电力科学研究院 | Multistage gas distribution device based on Dalton voltage division method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115212738A (en) * | 2022-06-29 | 2022-10-21 | 广西电网有限责任公司电力科学研究院 | Multistage gas distribution device based on Dalton voltage division method |
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