CN113484365A

CN113484365A - High-stability dew point fixing device

Info

Publication number: CN113484365A
Application number: CN202110794536.5A
Authority: CN
Inventors: 沈淘淘; 姜盈盈; 宋进; 秦亭亭
Original assignee: Shanghai Institute of Measurement and Testing Technology
Current assignee: Shanghai Institute of Measurement and Testing Technology
Priority date: 2021-07-14
Filing date: 2021-07-14
Publication date: 2021-10-08
Anticipated expiration: 2041-07-14
Also published as: CN113484365B

Abstract

The invention discloses a high-stability dew point device, which comprises a stabilizing support, wherein a heat-insulating tank is arranged in the stabilizing support, a first flowmeter and a second flowmeter are respectively arranged on two sides in the stabilizing support, the input end of the first flowmeter is communicated with a gas tank through a gas inlet communicating copper pipe, the output end of the first flowmeter is communicated with a first gas inlet copper pipe, one side of the top of the heat-insulating tank is respectively provided with a temperature sensor and a gas difference meter, the detection ends of the temperature sensor and the gas difference meter extend to the inner cavity of the heat-insulating tank, the output end of the second flowmeter is communicated with a precision dew point meter through a gas outlet communicating copper pipe, the input end of the second flowmeter is communicated with a first gas outlet copper pipe, one end of the first gas outlet copper pipe is inserted into the inner cavity of the heat-insulating tank and is communicated with a water collector, and one side of the water collector is communicated with a snakelike copper pipe. The stability assessment requirement of the precision dew point instrument is met.

Description

High-stability dew point fixing device

Technical Field

The invention relates to the technical field of dew point instrument fixing devices, in particular to a high-stability dew point fixing device.

Background

The dew point instrument is used for detecting the moisture content in various gases, and the principle is that under the condition of constant pressure, the water vapor in the gases is cooled to a condensed phase, namely, the flat surface of the water vapor and water (or ice) in the gases presents a thermodynamic equilibrium state, and the temperature at the moment is accurately measured and is the dew point temperature of the gases. The dew point instrument is widely applied to various industries such as electric power, petrifaction, natural gas, steel, microelectronics and the like. The precision dew point instrument is a mirror dew point instrument with semiconductor refrigeration and photoelectric automatic balance. The precision dew point meter has better linearity in the full-range, has higher measurement accuracy in a low-temperature environment, and is the only instrument with very accurate humidity measurement results in the full-temperature range.

Because the precision dew point meter is relatively complex in structure and numerous in influencing factors, even if normal inspection is guaranteed (generally once every year), drift is easy to occur after months, the stability is not good enough, and deviation is easy to occur in quantity value transmission and daily verification and calibration work. Therefore, the stability assessment of the precision dew point instrument is an important link for guaranteeing the transmission of the humidity value, and the most commonly used method for the stability assessment of the precision dew point instrument is as follows: the stability of the precision dew point instrument is checked by using the same-grade precision dew point instrument or a low-grade hygrothermograph as an 'inspection standard'. However, this method is used because the humidity field currently lacks a high stability check standard, and there are various defects, such as: expensive, inconvenient operation, poor reliability and the like. With the development of industry and science and technology, the stability requirement of the precision dew point meter is higher and higher, so that the development of a high-stability fixed dew point device for the fixed value and stability check of the precision dew point meter is urgent and important.

Disclosure of Invention

The present invention is directed to a device for fixing a dew point with high stability, so as to solve the problems mentioned in the background art.

In order to achieve the purpose, the invention provides the following technical scheme: a high-stability dew point fixing device comprises a stabilizing support, wherein a heat preservation tank is fixedly arranged in the stabilizing support, a sealing cover covers the top end of the heat preservation tank, a first flowmeter and a second flowmeter are respectively and fixedly arranged on the two sides in the stabilizing support and positioned at the top of the heat preservation tank, the input end of the first flowmeter is fixedly communicated with a gas tank through a gas inlet communicating copper pipe, the output end of the first flowmeter is fixedly communicated with a first gas inlet copper pipe, the bottom end of the first gas inlet copper pipe is inserted into the inner cavity of the heat preservation tank, a temperature sensor and a gas difference meter are respectively and fixedly arranged on one side, positioned at the top of the heat preservation tank, between the first gas outlet copper pipe and the first gas inlet copper pipe, the detection end of the temperature sensor and the detection end of the gas difference meter both extend to the inner cavity of the heat preservation tank, and the output end of the second flowmeter is fixedly communicated with a precision dew point instrument through the gas outlet communicating copper pipe, the input end of the second flowmeter is fixedly communicated with a first gas outlet copper pipe, one end of the first gas outlet copper pipe is inserted into an inner cavity of the heat-preservation tank and is fixedly communicated with a water collector, one side of the water collector is fixedly communicated with a snake-shaped copper pipe, one side of the snake-shaped copper pipe is fixedly communicated with a second gas inlet copper pipe, and the top end of the second gas inlet copper pipe is sleeved with a second water absorption sponge.

As a preferable technical scheme of the invention, an O-shaped ring is sleeved at the joint of the sealing cover and the heat-preservation tank.

As a preferable technical scheme of the invention, the bottom end of the heat preservation tank is fixedly communicated with a liquid discharge pipe, and one end of the liquid discharge pipe is fixedly communicated with a ball valve.

As a preferable technical scheme of the invention, one end of the surface of the heat-preservation tank is fixedly communicated with a vacuum pump exhaust pipe, and one end of the vacuum pump exhaust pipe is fixedly communicated with a pneumatic valve.

As a preferable technical scheme of the invention, an inner cavity of the heat-preserving tank is filled with an ice-water mixture, the depth of the ice-water mixture is 25cm, the bottom of the second air inlet copper pipe, the bottom of the first air outlet copper pipe, the detection end of the temperature sensor and the bottom of the first air inlet copper pipe are all immersed in the ice-water mixture, and the serpentine copper pipe and the water collector are all immersed in the ice-water mixture.

As a preferable technical scheme of the invention, a first water-absorbing sponge is bonded on the top of the inner cavity of the water collector.

Compared with the prior art, the invention has the beneficial effects that:

the device makes up the defect of a stability assessment method of the precision dew point instrument, meets the stability assessment of the precision dew point instrument, can be popularized to other metering technical mechanisms and enterprises at all levels for stability assessment of the precision dew point instrument due to the advantages of low research and development cost, simplicity and convenience in operation, easiness in reproduction, high stability and the like, can be used as a high stability comparison transmission standard for comparison of the quantity value of the precision dew point instrument, and provides strong technical support for guaranteeing the accuracy and reliability of the humidity value in the national range.

Drawings

FIG. 1 is a front view of the present invention;

FIG. 2 is a side view of the present invention;

FIG. 3 is a top view of the present invention;

FIG. 4 is a cross-sectional view of the insulated tank of the present invention;

fig. 5 is a sectional view of the sump according to the present invention.

In the figure: 1. a stabilizing support; 2. a heat preservation tank; 3. a liquid discharge pipe; 4. a vacuum pump exhaust pipe; 5. a sealing cover; 6. an O-shaped ring; 7. a first copper vent pipe; 8. a first inlet copper tube; 9. a second flow meter; 10. a first flow meter; 11. a first absorbent sponge; 12. a temperature sensor; 13. a precision dew point meter; 14. a gas tank; 15. a gas difference meter; 16. a second air inlet copper pipe; 17. a serpentine copper tube; 18. a water collector; 19. a second absorbent sponge; 20. the air outlet is communicated with the copper pipe; 21. the air inlet is communicated with the copper pipe.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-5, the present invention provides a high-stability dew point fixing device, which includes a stabilizing bracket 1, a thermal insulation tank 2 is fixedly installed inside the stabilizing bracket 1, a sealing cover 5 is covered on the top end of the thermal insulation tank 2, a first flowmeter 10 and a second flowmeter 9 are respectively and fixedly installed on two sides inside the stabilizing bracket 1 and on the top of the thermal insulation tank 2, an air tank 14 is fixedly communicated with an input end of the first flowmeter 10 through an air inlet communicating copper pipe 21, a first air inlet copper pipe 8 is fixedly communicated with an output end of the first flowmeter 10, a bottom end of the first air inlet copper pipe 8 is inserted into an inner cavity of the thermal insulation tank 2, a temperature sensor 12 and an air difference meter 15 are respectively and fixedly installed on one side of the top of the thermal insulation tank 2 between the first air outlet copper pipe 7 and the first air inlet copper pipe 8, and a detection end of the temperature sensor 12 and a detection end of the air difference meter 15 both extend into the inner cavity of the thermal insulation tank 2, the output end of the second flowmeter 9 is fixedly communicated with a precision dew-point meter 13 through an air outlet communicating copper pipe 20, the input end of the second flowmeter 9 is fixedly communicated with a first air outlet copper pipe 7, one end of the first air outlet copper pipe 7 is inserted into an inner cavity of the heat preservation tank 2 and is fixedly communicated with a water collector 18, one side of the water collector 18 is fixedly communicated with a snake-shaped copper pipe 17, one side of the snake-shaped copper pipe 17 is fixedly communicated with a second air inlet copper pipe 16, and the top end of the second air inlet copper pipe 16 is sleeved with a second water absorption sponge 19.

Preferably, the joint of the sealing cover 5 and the heat-preserving tank 2 is sleeved with an O-shaped ring 6, so that the sealing performance of the inner cavity of the heat-preserving tank 2 is ensured.

Preferably, the bottom end of the heat preservation tank 2 is fixedly communicated with a liquid discharge pipe 3, and one end of the liquid discharge pipe 3 is fixedly communicated with a ball valve, so that liquid can be discharged conveniently.

Preferably, one end of the surface of the heat preservation tank 2 is fixedly communicated with a vacuum pump exhaust tube 4, and one end of the vacuum pump exhaust tube 4 is fixedly communicated with a pneumatic valve, so that exhaust is facilitated.

Preferably, the inner cavity of the heat preservation tank 2 is filled with an ice-water mixture, the depth of the ice-water mixture is 25cm, the bottom of the second air inlet copper pipe 16, the bottom of the first air outlet copper pipe 7, the detection end of the temperature sensor 12 and the bottom of the first air inlet copper pipe 8 are all immersed in the ice-water mixture, and the snake-shaped copper pipe 17 and the water collector 18 are all immersed in the ice-water mixture, although the heat preservation tank 2 is in a sealed state, heat conduction convection between the sealing cover 5 and the outside cannot be completely avoided, so that the temperature of the gas phase space cannot be accurately maintained at 0 ℃, but may be slightly higher than the temperature, therefore, part of the air outlet pipes are immersed in the ice-water mixture for cooling and saturation, and the dew point temperature of the outlet gas can be guaranteed to be 0 ℃.

Preferably, the first water absorption sponge 11 is bonded on the top of the inner cavity of the water collector 18, so that water drops are prevented from entering a pipeline and being brought out to a dew point instrument probe along with saturated gas, and the test result is influenced.

In particular use, the physical properties at 0 ℃ of an ice-water mixture at standard atmospheric pressure are used, and defined in combination with the dew point: the dew point temperature of a saturated gas with the temperature of 0 ℃ under the standard atmospheric pressure is 0 ℃, firstly, dry gas is used for blowing the inner cavities of a first air outlet copper pipe 7, a second air inlet copper pipe 16 and a snake-shaped copper pipe 17 for five minutes, vapor and impurity dust in the pipeline are discharged to ensure the dryness and cleanness of the pipeline, then an ice water mixture with the height of 25cm is added into the inner cavity of a heat preservation tank 2, water drops on the inner wall of the heat preservation tank 2 and the pipeline are wiped, a sealing cover 5 is tightly covered, the temperature of the inner cavity of the heat preservation tank 2 is monitored by a temperature sensor 12, the internal and external differential pressure of the heat preservation tank 2 is monitored by a gas difference meter 15, then, a first flow meter 10 and a second flow meter 9 are respectively used for controlling the air outlet flow and the air inlet flow to be adjusted to be 0.5L/min and are connected with a precise dew point meter 13 for measurement, high-purity liquid nitrogen in a gas tank 14 is blown into the bottom of the ice water mixture by an air inlet communicating copper pipe 21 and the first air inlet copper pipe 8, the gas forms saturated gas with the temperature of 0 ℃ after passing through the ice-water mixture and gathers in the space above the heat-preserving tank 2, the temperature in the heat-preserving tank 2 reaches a balanced state after a certain time, then the saturated gas enters the precise dew point instrument 13 for dew point value test through the second gas inlet copper pipe 16, the S-shaped copper pipe 17, the water collector 18, the first gas outlet copper pipe 7 and the gas outlet communication copper pipe 20, and the precision dew point instrument 13 is judged according to the result difference between the measured value of the precise dew point instrument 13 and the dew point temperature of 0 ℃; although the heat preservation tank 2 is in a sealed state, the heat conduction convection between the sealing cover 5 and the outside cannot be completely avoided, so that the temperature of a gas phase space cannot be accurately maintained at 0 ℃, but may be slightly higher than the temperature, therefore, the serpentine copper tube 17 and the water collector 18 are immersed in an ice-water mixture for cooling and saturation, and the dew point temperature of the outlet gas can be ensured to be 0 ℃; condensed water inevitably occurs in the process of cooling and saturating gas, if the condensed water on the inner wall of the gas outlet pipeline is gathered to a certain amount, the condensed water is easily taken out of the pipeline by the gas and is contacted with a probe of the precision dew point instrument 13, so that the measurement result is higher, a water collector 18 is additionally arranged between a snakelike copper pipe 17 and a first gas outlet copper pipe 7, and redundant water drops are all gathered at the bottom of the water collector 18, so that the dew point temperature of the gas led out from the upper end of the water collector 18 is ensured to be 0 ℃, meanwhile, in order to prevent the small water drops from entering the pipeline, the top end of a second gas inlet copper pipe 16 and the top of the inner wall of the water collector 18 are respectively provided with a second water absorption sponge 19 and a first water absorption sponge 11, so as to prevent the small water drops from entering the pipeline, the defect problem of a stability assessment method of the precision dew point instrument 13 is solved by utilizing the device, the stability assessment of the precision dew point instrument 13 is met, and the device is low in research and development cost, The method has the advantages of simple and convenient operation, easy reappearance, high stability and the like, can be popularized to other metering technical mechanisms and enterprises at all levels for stability assessment of the precision dew point instrument 13, can also be used as a high-stability comparison transmission standard for comparison of the quantity values of the precision dew point instrument 13, and provides strong technical support for ensuring the accuracy and reliability of the humidity value in the national range.

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes in the embodiments and/or modifications of the invention can be made, and equivalents and modifications of some features of the invention can be made without departing from the spirit and scope of the invention.

Claims

1. The utility model provides a fixed dew point's of high stability device, includes outrigger (1), its characterized in that: the inside fixed mounting who stabilizes support (1) has heat preservation jar (2), the top of heat preservation jar (2) is stamped sealed lid (5), the inside both sides of stabilizing support (1) just are located the top of heat preservation jar (2) is fixed mounting respectively has first flowmeter (10) and second flowmeter (9), the input of first flowmeter (10) has gas pitcher (14) through the fixed intercommunication of intercommunication copper pipe (21) that admits air, the fixed intercommunication of the output of first flowmeter (10) has first air inlet copper pipe (8), insert the bottom of first air inlet copper pipe (8) the inner chamber of heat preservation jar (2), just be located between first air outlet copper pipe (7) and the first air inlet copper pipe (8) one side at heat preservation jar (2) top respectively fixed mounting have temperature sensor (12) and air differential meter (15), just the sense terminal of temperature sensor (12) with the sense terminal of air differential meter (15) all extends to the heat preservation is held The inner chamber of jar (2), the output of second flowmeter (9) is through giving vent to anger the fixed intercommunication of intercommunication copper pipe (20) and have accurate dew point hygrometer (13), the input of second flowmeter (9) is fixed to be communicated and has first copper pipe (7) of giving vent to anger, the inner chamber and the fixed intercommunication that insert heat preservation jar (2) of first copper pipe (7) of giving vent to anger have water collector (18), the fixed intercommunication in one side of water collector (18) has snakelike copper pipe (17), the fixed intercommunication in one side of snakelike copper pipe (17) has second copper pipe (16) of admitting air, the top cover of second copper pipe (16) of admitting air has connect second sponge (19) of absorbing water.

2. A high stability fixed dew point device as claimed in claim 1, wherein: and an O-shaped ring (6) is sleeved at the joint of the sealing cover (5) and the heat-preserving tank (2).

3. A high stability fixed dew point device as claimed in claim 1, wherein: the bottom end of the heat preservation tank (2) is fixedly communicated with a liquid discharge pipe (3), and one end of the liquid discharge pipe (3) is fixedly communicated with a ball valve.

4. A high stability fixed dew point device as claimed in claim 1, wherein: one end of the surface of the heat-insulating tank (2) is fixedly communicated with a vacuum pump exhaust pipe (4), and one end of the vacuum pump exhaust pipe (4) is fixedly communicated with a pneumatic valve.

5. A high stability fixed dew point device as claimed in claim 1, wherein: the inner cavity of the heat-preservation tank (2) is filled with an ice-water mixture, the depth of the ice-water mixture is 25cm, the bottom of the second air inlet copper pipe (16), the bottom of the first air outlet copper pipe (7), the detection end of the temperature sensor (12) and the bottom of the first air inlet copper pipe (8) are all immersed in the ice-water mixture, and the snake-shaped copper pipe (17) and the water collector (18) are all immersed in the ice-water mixture.

6. A high stability fixed dew point device as claimed in claim 1, wherein: the top of the inner cavity of the water collector (18) is bonded with a first water absorption sponge (11).