CN204789519U - Formaldehyde gas detector calibrating installation and system - Google Patents

Formaldehyde gas detector calibrating installation and system Download PDF

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Publication number
CN204789519U
CN204789519U CN201520393879.0U CN201520393879U CN204789519U CN 204789519 U CN204789519 U CN 204789519U CN 201520393879 U CN201520393879 U CN 201520393879U CN 204789519 U CN204789519 U CN 204789519U
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China
Prior art keywords
formaldehyde
gas
standard
pressure
standard gas
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CN201520393879.0U
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Chinese (zh)
Inventor
孙喜荣
秦宇
关卫军
于得水
张文娟
李域
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SHANXI INSTITUTE OF METROLOGY
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SHANXI INSTITUTE OF METROLOGY
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Abstract

The utility model provides a formaldehyde gas detector calibrating installation and system, the device includes: advance a kind unit for receive formaldehyde normal solution, and utilize formaldehyde normal solution preparation formaldehyde gas, the standard gas pitcher and advances a kind unit connection for store formaldehyde gas, the pressure unit is connected with standard gas pitcher for adjust the concentration in standard gas pitcher with control formaldehyde gas, the formaldehyde standard gas of required concentration is examined and determine in the preparation. The utility model provides a formaldehyde gas detector calibrating installation and system adopts static distribution method, and the formaldehyde standard gas of required concentration is decided to existing collating during the use, and formaldehyde standard gas receives the influence of environment less for measuring result is stable, therefore can regard its concentration as the standard value of examination. Additionally, the utility model provides a calibrating installation and the simple structure of system, the subassembly is few, and the operation is quicker simple and convenient, can repeatedly operate, has stronger practical application nature.

Description

Formaldehyde gas detector calibrating installation and system
Technical field
The utility model relates to formaldehyde gas detector calibrating field, is specifically related to a kind of formaldehyde gas detector calibrating installation and system.
Background technology
Formaldehyde is defined as suspect carcinogen matter by the World Health Organization (WHO) and FDA, is one of indoor-outdoor air major pollutants.Formaldehyde gas detector is quick, the portable direct-reading instrument detected for formaldehyde gas, and the order of accuarcy of its measurement result is related to the healthy of the people and life security, needs compare with formaldehyde standard gas and obtain and determine.Therefore, the formaldehyde gas detector just produced through demarcating, must meet index of dispatching from the factory and just to dispatch from the factory sale; And the formaldehyde gas detector in using also will through periodic calibration or calibration, to guarantee the accurate of instrument.Calibrating installation produces certain density formaldehyde standard gas, can be used as standard value, and the measurement result for formaldehyde gas detector compares with it, determines error size, thus judges whether met nominal technical indicator by test examination instrument.
Existing formaldehyde gas detector calibrating installation is primarily of compositions such as trioxymethylene anemostat standard substance, formaldehyde dynamic air-distributing device, zero gas, flowmeter, reduction valve, gas circuit pipe fittings, the assembly of this device is more, easily affected by environment, measurement result is unstable.In addition, this device need ensure long-time uninterrupted start, and use cost is higher, and source of error is more, affects measurement result.Core component trioxymethylene anemostat standard substance in this device is difficult to obtain, and causes existing apparatus in practice cannot widespread use.
Utility model content
The utility model provides a kind of formaldehyde gas detector calibrating installation and system, to solve that the measurement result that exists in existing Calibration Technology is unstable, use cost is high and in practice cannot the problem of widespread use.
First aspect, the utility model embodiment provides a kind of formaldehyde gas detector calibrating installation, and described device comprises:
Sample injection unit, for receiving formaldehyde standard solution, and utilizes described formaldehyde standard solution to prepare formaldehyde gas;
Standard gas cylinders, is connected with described sample injection unit, for storing described formaldehyde gas;
Pressure unit, is connected with described standard gas cylinders, for regulating the concentration of described formaldehyde gas in described standard gas cylinders, and the formaldehyde standard gas of preparation calibrating desired concn.
As the optimal way of such scheme, described device also comprises:
Vacuum unit, is connected with described standard gas cylinders, for utilizing before described formaldehyde standard solution prepares formaldehyde gas, keeps described standard gas cylinders to be vacuum state; Described vacuum unit comprises vacuum pump and vacuum meter.
As the optimal way of such scheme, described device also comprises:
Inflation unit, is connected with described sample injection unit, for utilizing after described formaldehyde standard solution prepares formaldehyde gas, provides described formaldehyde gas to enter the pressure of described standard gas cylinders; Described inflation unit comprises inflation inlet and gas filling valve.
As the optimal way of such scheme, described sample injection unit comprises injection port, sampling valve and sample chamber, and described sample chamber is used for formaldehyde standard solution described in splendid attire.
As the optimal way of such scheme, described standard gas cylinders inside is provided with temperature sensor and pressure transducer, and described temperature sensor and described pressure transducer are respectively used to the state of temperature information and the atmosphere pressure state information that gather described formaldehyde standard gas.
As the optimal way of such scheme, described pressure unit comprises high pressure gas holder, pressure controller and pressure control valve, and the pressure gas in described high pressure gas holder is nitrogen.
Second aspect, the utility model embodiment provides a kind of formaldehyde gas detector verification system, and described system comprises:
Calibrating installation, described calibrating installation is the formaldehyde gas detector calibrating installation described in first aspect;
Tested formaldehyde gas detector, is connected with the standard gas cylinders in described calibrating installation, for receiving described formaldehyde standard gas, and examines and determine based on described formaldehyde standard gas, generates verification result.
The formaldehyde gas detector calibrating installation that the utility model provides and system, adopt static volumetric method, during use, existing collating determines the formaldehyde standard gas of desired concn, and formaldehyde standard gas is less by the impact of environment, measurement result is stablized, thus can using the standard value of its concentration as calibrating.In addition, the calibrating installation that the utility model provides and system architecture are simple, and assembly is few, operates more fast and convenient, can repetitive operation, have stronger practical application.
Accompanying drawing explanation
In order to be illustrated more clearly in the technical scheme in the utility model embodiment, below the accompanying drawing used required in describing embodiment is briefly described, apparently, accompanying drawing in the following describes is only embodiments more of the present utility model, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.
The structured flowchart of the formaldehyde gas detector calibrating installation that Fig. 1 provides for the utility model embodiment;
The structured flowchart of the formaldehyde gas detector verification system that Fig. 2 provides for the utility model embodiment;
The process flow diagram of the formaldehyde gas detector calibration method that Fig. 3 provides for the utility model embodiment;
The structural representation of the formaldehyde gas detector verification system that Fig. 4 provides for the utility model embodiment.
Wherein, 1, standard gas cylinders, the 2, first gas circuit cross-over valve, 3, tensimeter, 4, exit flow operation valve, 5, tested formaldehyde gas detector, 6, vacuum pump, 7, vacuum meter, the 8, second gas circuit cross-over valve, 9, sample chamber, 10, sampling valve, 11, injection port, 12, inflation inlet, 13, gas filling valve, the 14, the 3rd gas circuit cross-over valve, 15, pressure control valve, 16, pressure controller, 17, high pressure gas holder.
Embodiment
For making the purpose of this utility model, technical scheme and advantage clearly, below in conjunction with accompanying drawing, the utility model embodiment is described in further detail.
The structured flowchart of the formaldehyde gas detector calibrating installation that Fig. 1 provides for the utility model embodiment, with reference to shown in Fig. 1, the utility model embodiment provides a kind of formaldehyde gas detector calibrating installation, and this device comprises:
Sample injection unit, for receiving formaldehyde standard solution, and utilizes this formaldehyde standard solution to prepare formaldehyde gas;
Standard gas cylinders, is connected with sample injection unit, for storing formaldehyde gas;
Pressure unit, is connected with standard gas cylinders, for the concentration of regulation and control formaldehyde gas in standard gas cylinders, and the formaldehyde standard gas of preparation calibrating desired concn.
Preferably, this device also comprises:
Vacuum unit, is connected with standard gas cylinders, for utilizing before formaldehyde standard solution prepares formaldehyde gas, keeps sample injection unit and standard gas cylinders to be vacuum state.
Preferably, this device also comprises:
Inflation unit, is connected with sample injection unit, for utilizing after formaldehyde standard solution prepares formaldehyde gas, provides formaldehyde gas to enter the pressure of described standard gas cylinders.
Adopt the formaldehyde gas detector calibrating installation of this embodiment, adopt static volumetric method, during use, existing collating determines the formaldehyde standard gas of desired concn, and formaldehyde standard gas is less by the impact of environment, measurement result is stablized, thus can using the standard value of its concentration as calibrating.In addition, this calibrating installation structure is simple, and assembly is few, operates more fast and convenient, can repetitive operation, has stronger practical application.
The structured flowchart of the formaldehyde gas detector verification system that Fig. 2 provides for the utility model embodiment, with reference to shown in Fig. 2, the utility model embodiment provides a kind of formaldehyde gas detector verification system, and this system comprises:
Calibrating installation, described calibrating installation is the formaldehyde gas detector calibrating installation described in above-described embodiment;
Tested formaldehyde gas detector, is connected with the standard gas cylinders in calibrating installation, for receiving formaldehyde standard gas, and examines and determine based on this formaldehyde standard gas, generates verification result.
Adopt the formaldehyde gas detector verification system of this embodiment, adopt static volumetric method, during use, existing collating determines the formaldehyde standard gas of desired concn, and formaldehyde standard gas is less by the impact of environment, measurement result is stablized, thus can using the standard value of its concentration as calibrating.In addition, this verification system structure is simple, and assembly is few, operates more fast and convenient, can repetitive operation, has stronger practical application.
The process flow diagram of the formaldehyde gas detector calibration method that Fig. 3 provides for the utility model embodiment, with reference to shown in Fig. 3, the utility model embodiment provides a kind of formaldehyde gas detector calibration method based on above-mentioned formaldehyde gas detector verification system, and the method comprises:
In sample injection unit, add formaldehyde standard solution, utilize formaldehyde standard solution to prepare formaldehyde gas in sample injection unit, formaldehyde gas Engage of standard gas tank stores;
By the concentration of pressure unit regulation and control formaldehyde gas in standard gas cylinders, the formaldehyde standard gas of preparation calibrating desired concn;
Formaldehyde standard gas enters tested formaldehyde gas detector, and tested formaldehyde gas detector is examined and determine based on formaldehyde standard gas, generates verification result.
Preferably, add formaldehyde standard solution in sample injection unit before, the method also comprises:
By vacuum unit, standard gas cylinders is remained vacuum state.
Preferably, utilize after formaldehyde standard solution prepares formaldehyde gas in sample injection unit, the method also comprises:
Inflation unit is utilized to provide the pressure of formaldehyde gas Engage of standard gas tank.
Adopt the formaldehyde gas detector calibration method of this embodiment, adopt static volumetric method, during use, existing collating determines the formaldehyde standard gas of desired concn, formaldehyde standard gas is less by the impact of environment, measurement result is stablized, thus can, using the standard value of its concentration as calibrating, operate more fast and convenient, can repetitive operation, there is stronger practical application.
The structural representation of the formaldehyde gas detector verification system that Fig. 4 provides for the utility model embodiment, with reference to shown in Fig. 4, in figure, arrow represents gas flow direction, this system comprises calibrating installation and tested formaldehyde gas detector, and wherein calibrating installation comprises vacuum unit, sample injection unit, inflation unit, standard gas cylinders 1 and pressure unit.
Wherein, vacuum unit comprises vacuum pump 6 and vacuum meter 7, sample injection unit comprises injection port 11, sampling valve 10 and sample chamber 9, this sample chamber 9 is for splendid attire formaldehyde standard solution, inflation unit comprises inflation inlet 12 and gas filling valve 13, pressure unit comprises high pressure gas holder 17, pressure controller 16 and pressure control valve 15, and this pressure controller 16 adopts PC50000,0.1 stage pressure controller, and the pressure gas in this high pressure gas holder 17 is nitrogen.
In addition, standard gas cylinders 1 adopts the metal high voltage gas tank through completely anti-adsorption treatment, effectively can prevent formaldehyde gas from adsorbing and affect the concentration of formaldehyde standard gas, atmospheric pressure General Requirements≤the 1MPa of its inside, the inside of standard gas cylinders 1 is provided with temperature sensor and pressure transducer, this temperature sensor and this pressure transducer are respectively used to state of temperature information and the atmosphere pressure state information of the formaldehyde standard gas gathering preparation, can the correlation behavior of gas in real-time monitored standard gas cylinders 1 by these two sensors.
Particularly, vacuum pump 6 is connected by the left side port of pipeline with the first gas circuit cross-over valve 2, and this section of pipeline is provided with vacuum meter 7, and this vacuum meter 7 can vacuum tightness in Real Time Observation standard gas cylinders 1 and associated pipe.
The downside port of the first gas circuit cross-over valve 2 is connected by the upside port of pipeline with the second gas circuit cross-over valve 8, the downside port of the second gas circuit cross-over valve 8 is connected with standard gas cylinders 1 by pipeline, the left side port of the second gas circuit cross-over valve 8 is connected with the left side port of exit flow operation valve 4 by pipeline, this section of pipeline is provided with tensimeter 3, this tensimeter 3 can the change of gaseous tension in Real Time Observation standard gas cylinders 1, and the right side port of exit flow operation valve 4 is connected with tested formaldehyde gas detector 5.
Injection port 11 is connected with the upside port of sampling valve 10, and the downside port of sampling valve 10 is connected by the entrance of pipeline with sample chamber 9, and the outlet of sample chamber 9 is connected by the right side port of pipeline with the first gas circuit cross-over valve 2.
Inflation inlet 12 is connected with the upside port of gas filling valve 13, and the downside port of gas filling valve 13 is connected by the upside port of pipeline with the 3rd gas circuit cross-over valve 14, and the left side port of the 3rd gas circuit cross-over valve 14 is connected by the entrance of pipeline with sample chamber 9.
High pressure gas holder 17 is connected with the downside port of pressure controller 16 by pipeline, the left side port of pressure controller 16 is connected with the right side port of pressure control valve 15 by pipeline, and the right side port of pressure control valve 15 is connected by the downside port of pipeline with the 3rd gas circuit cross-over valve 14.
In addition, the volume of standard gas cylinders 1 is generally 8L, and the formaldehyde standard gas of internal reservoir can meet repetitive measurement needs, and standard gas cylinders 1 is detachable and independently use.Utilize the atmospheric pressure of pressure controller 16 accurately in control criterion gas tank 1, thus the repeatability of the concentration of formaldehyde standard gas prepared by ensureing and stability.
When the formaldehyde gas detector verification system utilizing the utility model embodiment to provide is examined and determine, in advance according to the concentration of the required formaldehyde standard gas of calibrating, environment temperature and atmospheric pressure, calculate the consumption of formaldehyde standard solution and the final controlled pressure of standard gas cylinders 1, in the utility model embodiment, calculate the concentration of the required formaldehyde standard gas of calibrating according to the final controlled pressure of standard gas cylinders 1.
Closing presure operation valve 15 (to the right), the 3rd gas circuit cross-over valve 14 (left), exit flow operation valve 4 (left), the first gas circuit cross-over valve 2 (upwards) and sampling valve 10 (upwards), open gas filling valve 13 (downwards), gas filling valve 13 is in open mode in whole process always; Open the second gas circuit cross-over valve 8 (upwards), then open vacuum pump 6, standard gas cylinders 1 is evacuated to vacuum state, after the Exponential Stability of vacuum meter 7, close the second gas circuit cross-over valve 8 (left); Open sampling valve 10 (downwards), the formaldehyde standard solution calculating consumption is joined sample chamber 9 by injection port 11; Close sampling valve 10 (upwards), open the second gas circuit cross-over valve 8 (downwards), sample chamber 9 is communicated with standard gas cylinders 1, and formaldehyde standard solution is vaporizated into formaldehyde gas in airtight environment under low pressure, and formaldehyde standard solution can be vaporized completely in airtight environment under low pressure; After waiting for one minute, open the 3rd gas circuit cross-over valve 14 (upwards), formaldehyde gas utilizes the quick Engage of standard gas tank 1 of pressure of the gas entered from inflation inlet 12; Close the 3rd gas circuit cross-over valve 14 (downwards), thus close gas fill port; Open pressure control valve 15 (left), by pressure controller 16, high pressure gas holder 17 is communicated with standard gas cylinders 1, in nitrogen Engage of standard gas tank 1 in high pressure gas holder 17, preparation has the formaldehyde standard gas of calibrating desired concn, the final controlled pressure of pressure controller 16 control criterion gas tank 1 reaches specified pressure, under this specified pressure, the concentration of concentration needed for calibrating of formaldehyde standard gas; Open the first gas circuit cross-over valve 2 (downwards), the formaldehyde standard gas opened again in exit flow operation valve 4 (to the right) control criterion gas tank 1 enters in tested formaldehyde gas detector 5, tested formaldehyde gas detector 5 is examined and determine based on formaldehyde standard gas, by the actual value of more tested formaldehyde gas detector 5 to the detected value of this formaldehyde standard gas concentration and this formaldehyde standard gas concentration, generate verification result, determine the measuring error of tested formaldehyde gas detector 5.
The formaldehyde gas detector calibrating installation that the utility model embodiment provides, system and method, operation fast, easy, the concentration of the required formaldehyde standard gas of calibrating is very accurate, the repeatability of calibrating and good stability, the uncertainty < 3% of calibrating, not only can realize the accurate calibrating of PARA FORMALDEHYDE PRILLS(91,95) gas detecting instrument, can also realize methyl alcohol, ethanol, ether, benzene, cyclopentane, oxirane, acetone, a series of low boiling organic gas such as VOC detector, the calibrating of leak locator or analyser etc., solve the transmission of quantity value of a large class gas detecting instrument and problem of tracing to the source.
It should be noted that, mentioned in embodiment of the present utility model " on ", D score, "left", "right" all with each direction shown in the drawings for benchmark, these words being used for limiting direction are only used to be convenient to illustrate, do not represent the restriction to the concrete technical scheme of the utility model.
The foregoing is only preferred embodiment of the present utility model, not in order to limit the utility model, all within spirit of the present utility model and principle, any amendment done, equivalent replacement, improvement etc., all should be included within protection domain of the present utility model.

Claims (7)

1. a formaldehyde gas detector calibrating installation, is characterized in that, described device comprises:
Sample injection unit, for receiving formaldehyde standard solution, and utilizes described formaldehyde standard solution to prepare formaldehyde gas;
Standard gas cylinders, is connected with described sample injection unit, for storing described formaldehyde gas;
Pressure unit, is connected with described standard gas cylinders, for the concentration of formaldehyde gas described in regulation and control in described standard gas cylinders, and the formaldehyde standard gas of preparation calibrating desired concn.
2. device according to claim 1, is characterized in that, described device also comprises:
Vacuum unit, is connected with described standard gas cylinders, for utilizing before described formaldehyde standard solution prepares formaldehyde gas, keeps described standard gas cylinders to be vacuum state; Described vacuum unit comprises vacuum pump and vacuum meter.
3. device according to claim 2, is characterized in that, described device also comprises:
Inflation unit, is connected with described sample injection unit, for utilizing after described formaldehyde standard solution prepares formaldehyde gas, provides described formaldehyde gas to enter the pressure of described standard gas cylinders; Described inflation unit comprises inflation inlet and gas filling valve.
4., according to the arbitrary described device of claims 1 to 3, it is characterized in that, described sample injection unit comprises injection port, sampling valve and sample chamber, and described sample chamber is used for formaldehyde standard solution described in splendid attire.
5. according to the arbitrary described device of claims 1 to 3, it is characterized in that, described standard gas cylinders inside is provided with temperature sensor and pressure transducer, and described temperature sensor and described pressure transducer are respectively used to the state of temperature information and the atmosphere pressure state information that gather described formaldehyde standard gas.
6., according to the arbitrary described device of claims 1 to 3, it is characterized in that, described pressure unit comprises high pressure gas holder, pressure controller and pressure control valve, and the pressure gas in described high pressure gas holder is nitrogen.
7. a formaldehyde gas detector verification system, is characterized in that, described system comprises:
Calibrating installation, the formaldehyde gas detector calibrating installation of described calibrating installation according to any one of claim 1 to 6;
Tested formaldehyde gas detector, is connected with the standard gas cylinders in described calibrating installation, for receiving described formaldehyde standard gas, and examines and determine based on described formaldehyde standard gas, generates verification result.
CN201520393879.0U 2015-06-09 2015-06-09 Formaldehyde gas detector calibrating installation and system Expired - Fee Related CN204789519U (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104865354A (en) * 2015-06-09 2015-08-26 陕西省计量科学研究院 Formaldehyde gas detector verification device, system and method
CN109655545A (en) * 2018-12-28 2019-04-19 山东玉皇化工有限公司 A kind of chromatographic analysis device and method preparing tert-butylamine for isobutene

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104865354A (en) * 2015-06-09 2015-08-26 陕西省计量科学研究院 Formaldehyde gas detector verification device, system and method
CN109655545A (en) * 2018-12-28 2019-04-19 山东玉皇化工有限公司 A kind of chromatographic analysis device and method preparing tert-butylamine for isobutene

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CF01 Termination of patent right due to non-payment of annual fee
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Granted publication date: 20151118

Termination date: 20170609