CN209802606U - Valve low-temperature leakage detection system - Google Patents

Valve low-temperature leakage detection system Download PDF

Info

Publication number
CN209802606U
CN209802606U CN201920584767.1U CN201920584767U CN209802606U CN 209802606 U CN209802606 U CN 209802606U CN 201920584767 U CN201920584767 U CN 201920584767U CN 209802606 U CN209802606 U CN 209802606U
Authority
CN
China
Prior art keywords
valve
pipeline
vacuum
mass spectrometer
air inlet
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn - After Issue
Application number
CN201920584767.1U
Other languages
Chinese (zh)
Inventor
吕秉坤
徐冬
李来风
刘辉明
黄荣进
沈福至
李旭
贾朋
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Technical Institute of Physics and Chemistry of CAS
Original Assignee
Technical Institute of Physics and Chemistry of CAS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Technical Institute of Physics and Chemistry of CAS filed Critical Technical Institute of Physics and Chemistry of CAS
Priority to CN201920584767.1U priority Critical patent/CN209802606U/en
Application granted granted Critical
Publication of CN209802606U publication Critical patent/CN209802606U/en
Withdrawn - After Issue legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Landscapes

  • Examining Or Testing Airtightness (AREA)

Abstract

The utility model relates to a valve low temperature leak hunting test technical field especially relates to a valve low temperature leak hunting system, include: supply gas distribution device, refrigerating plant, first helium mass spectrometer leak detector, second helium mass spectrometer leak detector, many air inlet pipelines, many air outlet pipelines and vacuum test platform, supply gas distribution device through air inlet pipeline and vacuum test platform intercommunication, first helium mass spectrometer leak detector and vacuum test platform intercommunication, second helium mass spectrometer leak detector through air outlet pipeline and vacuum test platform intercommunication, every pair of air inlet pipeline is connected respectively at the both ends that correspond the valve that awaits measuring with air outlet pipeline, at first helium mass spectrometer leak detector, second helium mass spectrometer leak detector, air inlet pipeline and air outlet pipeline are equipped with the valve respectively. The utility model discloses utilize refrigerating plant as the cold source, improved experimental security and reliability, reduce human cost and test cost, sample temperature is accurate controllable, and one-time test can detect a plurality of valves that await measuring, and test cycle is short.

Description

Valve low-temperature leakage detection system
Technical Field
the utility model relates to a valve low temperature leak hunting test technical field especially relates to a valve low temperature leak hunting system.
Background
Cryogenic technology is not only closely related to people's contemporary high quality life but is also inseparable from many of the world's most advanced scientific studies such as superconducting technology, aerospace and aviation technology, high energy physics, controlled thermonuclear fusion, far infrared detection, precision electromagnetic metrology, biology and life sciences. With the development of modern scientific technology, industrial production, new energy development and aerospace industry, low-temperature valves have been used in many occasions. Cryogenic valves are widely used, but are also prone to leakage and have high manufacturing requirements. Because the low-temperature valve mostly works in an ultralow-temperature area below the liquid nitrogen temperature, compared with a conventional valve, the low-temperature valve has special requirements on material selection, structural design, manufacturing process, performance detection and the like. For example, solenoid valves are essential components of satellite launch power propulsion systems and attitude control systems. It can encounter severe vacuum low-temperature or high-temperature environment on the transfer orbit or space operation orbit of the satellite. The sealing performance or leakage rate of the solenoid valve is related to the effectiveness of storage, utilization and use of the fuel or propulsion medium carried by the satellite, and also to the reliability of the control. The sealing performance of the solenoid valve should be tested in a space cold and hot environment simulated on the ground, namely, the leakage rate of the solenoid valve is measured in a vacuum cold and hot environment. Particularly, the vacuum low-temperature environment has a greater influence on the performance of the vacuum low-temperature environment. This is proven by failures of some satellites at home and abroad. Sometimes, a small solenoid valve can cause catastrophic damage to the entire satellite. Therefore, the low temperature valve must be tested at low temperature in addition to the normal temperature test. The main purpose of the low temperature test is to verify the operation and sealing performance of the low temperature valve in a low temperature state. The operation performance requires that the valve is opened and closed flexibly, and the valve rod and the valve seat can not be clamped because of low-temperature deformation. The sealing performance requires that the amount of leakage from the valve sealing surface be less than the allowable amount.
The leak detection method adopted in the performance test of the normal-temperature valve is simpler, and the methods of a flowmeter detection method, a liquid and gas discharge method, a helium mass spectrum leak detection method, a soap liquid coating method, a bubble method and the like can be respectively adopted for the air tightness test according to different requirements of allowable leakage rate indexes. After the test environment is changed from normal temperature to low temperature, the working mechanism of the valve is greatly changed, and the sealing material and the sealing structure adopted by the corresponding parts, the manufacturing process method of the sealing structure and the leak detection method of the air tightness are also greatly changed. The conventional bubble method, the liquid and gas discharging method, the soap bubble method and the like can not detect the air leakage of the valve. At present, the leakage detection of a low-temperature valve and a closed container adopts a helium mass spectrum leakage detection method. The helium mass spectrum leak detection method is an ideal method for quickly positioning and quantitatively detecting the leak of various pieces to be detected by taking helium as exploring gas according to the principle of mass spectrum analysis. Because helium is inert gas, the gas has no pollution to the atmosphere and is safe to use; helium has small atomic weight, small viscosity, high detection sensitivity, high speed and wide application range, and can easily permeate any possible leakage rate; in addition, the content of helium in the atmosphere is small (only five parts per million), the ion mass is greatly different from that of other gas ions, and the method is not easy to be interfered and cannot be misjudged. Compared with the prior leak detection methods, the method is superior.
At present, a low-temperature valve leak test generally adopts 2 modes of low-temperature gas precooling and low-temperature medium soaking to provide a cold source. The low-temperature gas precooling means that gas is subjected to heat exchange by a low-temperature medium to obtain low-temperature gas, and then the high-flow low-temperature gas passes through a test system and is precooled to a test required temperature zone for performance test. The low-temperature medium soaking means that the test product and part of the system pipeline are soaked in the low-temperature medium, and the test is carried out after the product reaches a required temperature zone through sufficient heat exchange. A low-temperature performance test is carried out by adopting a low-temperature gas (cold helium gas) precooling mode, 2 media (liquid nitrogen and liquid hydrogen) need to be added in the test process, the outlet temperature of a test piece after precooling is only about 40K, and the precooling is finished by heat exchange between large-flow cold helium and a system, so that a large amount of resources and energy consumption are caused, and the temperature requirement of a valve test cannot be met. If a liquid hydrogen soaking and precooling mode is adopted, a large amount of liquid hydrogen can be consumed, meanwhile, hydrogen belongs to a flammable and combustible medium, and a large potential safety hazard exists in the test. Another drawback of conventional testing devices is that: the system is complex, the safety and reliability are low, the sample replacement time is long, the efficiency is low, the operation is complex and tedious, the test period is long, only the test at a specific temperature can be realized, the temperature cannot be accurately controlled, the time cost, the labor cost and the test cost are high, and particularly when a large number of samples need to be tested.
SUMMERY OF THE UTILITY MODEL
The embodiment of the utility model provides a valve low temperature leak hunting system for valve low temperature leak hunting mode among the solution prior art causes a large amount of resources and energy resource consumption, and the system architecture is complicated, and fail safe nature is low, and the sample change time is long, and is inefficient, and the operation is loaded down with trivial details, and the test cycle length can only realize the experiment under the specific temperature, can't accomplish that the temperature is accurate controllable, the higher problem of time cost, human cost and testing expense.
The embodiment of the utility model provides a valve low temperature leak hunting system, include: supply distributing device, refrigerating plant, first helium mass spectrometer leak detector, second helium mass spectrometer leak detector, many air inlet pipelines, many air outlet pipelines and vacuum test platform, refrigerating plant and the valve that awaits measuring all locate vacuum test platform, supply distributing device through the air inlet pipeline with vacuum test platform intercommunication, first helium mass spectrometer leak detector with vacuum test platform intercommunication, second helium mass spectrometer leak detector through air outlet pipeline with vacuum test platform intercommunication, it is every to the air inlet pipeline with the air outlet pipeline is connected respectively and is corresponding the both ends of valve that awaits measuring first helium mass spectrometer leak detector, second helium mass spectrometer leak detector, air inlet pipeline and air outlet pipeline are equipped with the valve respectively.
The heat exchange device comprises a heat exchange cavity, the heat exchange cavity is provided with a medium inlet and a medium outlet, and the middle section of the air inlet pipeline is made into a coil pipe and extends into the heat exchange cavity to exchange heat with a heat exchange medium in the heat exchange cavity.
Wherein, supply distribution device includes parallel connection's confession distributing pipe way and sweeps the pipeline, supply distributing pipe way and helium source intercommunication, and supply distributing pipe way is equipped with valve, flowmeter and pressure sensor, sweep pipeline and nitrogen gas jar intercommunication, just it is equipped with the valve to sweep the pipeline.
Wherein, vacuum test platform includes temperature sensor, vacuum cover, lower base, first vacuum pump and second vacuum pump, refrigerating plant with the valve that awaits measuring all place in on the lower base, and by the vacuum cover is sealed, first vacuum pump with vacuum cover intercommunication, second vacuum pump and gas outlet pipe way intercommunication, temperature sensor locates in the vacuum cover.
The lower base comprises a cross flat plate shape with three short sides and a long side, the three short sides are provided with grooves, the grooves are connected with the multiple air inlet pipelines, and the long side fixes the valve to be tested through a valve connecting piece.
The valve connecting piece comprises a clamping plate and an upper base, the clamping plate fixes the valve to be tested on the lower base, and the upper base is buckled on the clamping plate.
The valve to be tested is arranged on the inner side of the vacuum cover, the vacuum cover is provided with an opening connected with the first vacuum pump, a first hole door connected with the air inlet pipeline and a second hole door connected with the air outlet pipeline.
The embodiment of the utility model provides a valve low temperature leak hunting system utilizes refrigerating plant as the cold source, realizes carrying out the leak hunting test of valve under adjustable low temperature environment, has solved the excessive dependence of valve low temperature leak hunting system to cryogenic liquid among the prior art, leads to the test operation complicated, causes the problem of the extravagant a large amount of raw and other materials as cryogenic liquid; liquid hydrogen is got rid of as a test cold source, so that the safety and reliability of the test are greatly improved; the system complexity is reduced, and the labor cost and the test cost are reduced; meanwhile, the valve low-temperature leakage detection system provided by the utility model also realizes the accurate and controllable sample temperature; a plurality of valves to be tested can be detected in one test, rapid rewarming replacement is supported, the sample is convenient to replace, and the test period is short.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are 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 structural diagram of a valve low-temperature leak detection system of the present invention;
FIG. 2 is a schematic structural view of the lower base of the present invention;
fig. 3 is a schematic structural diagram of the vacuum testing platform of the present invention.
In the figure: 11. a refrigerator; 12. a shield case; 13. a vacuum hood; 14. a lower base; 15. a valve to be tested; 16. a splint; 17. a thin film heater; 18. an upper base; 19. a temperature sensor; 1. a first helium mass spectrometer leak detector; 2. a second helium mass spectrometer leak detector; 3. a first vacuum pump; 4. a pre-cooling device; 41. a heat exchange cavity; 42. a coil pipe; 51. a gas distribution table; 52. a source of helium gas; 53. a nitrogen tank; 6. an air intake line; 7. an air outlet pipeline; 8. a supply and distribution pipeline; 9. purging the pipeline; 10. a second vacuum pump.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. Based on the embodiments in 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.
As shown in fig. 1-3, the utility model discloses a valve low temperature leak detection system, include: supply distributing device, refrigerating plant, first helium mass spectrometer leak detector 1, second helium mass spectrometer leak detector 2, many air inlet pipeline 6, many air outlet pipeline 7 and vacuum test platform, refrigerating plant and valve 15 that awaits measuring all locate in the vacuum test platform, supply distributing device through air inlet pipeline 6 with the vacuum test platform intercommunication, first helium mass spectrometer leak detector 1 with the vacuum test platform intercommunication, second helium mass spectrometer leak detector 2 through air outlet pipeline 7 with the vacuum test platform intercommunication, every pair air inlet pipeline 6 with air outlet pipeline 7 is connected respectively at corresponding the both ends of valve 15 that awaits measuring first helium mass spectrometer leak detector 1, second helium mass spectrometer leak detector 2, air inlet pipeline 6 and air outlet pipeline 7 are equipped with the valve respectively.
Specifically, a gas supply and distribution device inputs helium gas into the gas inlet pipeline 6, so that the whole testing passage is filled with the helium gas, and a testing environment is provided for the first helium mass spectrometer leak detector 1 and the second helium mass spectrometer leak detector 2; the refrigerating device can be a refrigerator 11 and the like, can adopt a G-M refrigerator, a pulse tube refrigerator or a Stirling refrigerator, preferentially adopts a single-stage G-M refrigerator, replaces 2 cold source supply modes of low-temperature gas pre-cooling and low-temperature medium soaking, and can control the environmental temperature to be 20K-300K (thermodynamic temperature scale, unit: Kelvin); the first helium mass spectrometer leak detector 1 and the second helium mass spectrometer leak detector 2 are used for detecting the leak rate of the valve 15 to be detected; the utility model discloses can leak hunting a plurality of valves 15 that await measuring, consequently need many air inlet pipe ways 6 and many air outlet pipe ways 7 to connect to utilize the switching of each pipeline of valve control, in order to leak hunting test (including interior hourglass detection, the inlet end leaks outward and detects and the whole leak hunting rate detection etc. that leaks outward) to valves 15 that await measuring in proper order.
The utility model discloses a valve low temperature leak hunting system utilizes refrigerating plant as the cold source, realizes carrying out the leak hunting test of valve under adjustable low temperature environment, has solved the excessive dependence of valve low temperature leak hunting system to cryogenic liquid among the prior art, leads to the test operation complicated, causes the problem of the raw and other materials waste as cryogenic liquid in a large number; liquid hydrogen is got rid of as a test cold source, so that the safety and reliability of the test are greatly improved; the system complexity is reduced, and the labor cost and the test cost are reduced; meanwhile, the valve low-temperature leakage detection system provided by the utility model also realizes the accurate and controllable sample temperature; a plurality of valves to be tested can be detected in one test, rapid rewarming replacement is supported, the sample is convenient to replace, and the test period is short.
The heat exchanger comprises a pre-cooling device 4, wherein the pre-cooling device 4 comprises a heat exchange cavity 41, the heat exchange cavity 41 is provided with a medium inlet and a medium outlet, a coil 42 is made at the middle section of the air inlet pipeline 6 and extends into the heat exchange cavity 41 to exchange heat with a heat exchange medium in the heat exchange cavity 41. The pre-cooling device 4 pre-cools the helium in the air inlet pipeline 6, and enhances the temperature control of the system environment. Specifically, in this embodiment, the heat exchange cavity 41 has a vacuum heat insulation interlayer, so as to avoid the loss of cold energy, and the heat exchange cavity 41 serves as a heat exchange medium to exchange heat with helium in the air inlet pipeline 6. This embodiment adopts the liquid nitrogen to cool off as heat transfer medium, and the helium that the liquid nitrogen got into from the medium import and intake pipe 6 carries out the heat transfer, in order to improve heat exchange efficiency, makes intake pipe 6 coil pipe 42 structure at heat transfer part, carries out the precooling with the helium of normal atmospheric temperature, and the liquid nitrogen after the heat transfer becomes nitrogen gas and discharges from the medium export.
Based on the above embodiment, the utility model discloses an approximate work flow does: an air inlet pipeline 6 led out from the air supply and distribution device is divided into 5 parallel pipelines which respectively and independently correspond to 5 valves for leak detection, after precooling is carried out by a precooling device 4, helium is cooled to a liquid nitrogen temperature area, a terminal is connected with a refrigerating device, the helium is cooled to the liquid hydrogen temperature area, and then the helium is connected with an air inlet of a valve 15 to be detected. The starting end of the gas outlet pipeline 7 is connected with a gas outlet of a valve 15 to be tested, 5 gas exhaust pipelines are connected in parallel for leak detection of 5 valves, the gas exhaust pipelines are led out of the vacuum detection platform and combined into a main gas exhaust pipeline after rewarming, and the tail end of the main gas exhaust pipeline is connected with a one-way valve for helium gas discharge or connected into a helium gas recovery device.
Wherein, supply distribution device includes parallel connection's confession distributing pipe way 8 and sweeps pipeline 9, supply distributing pipe way 8 and helium source 52 intercommunication, just supply distributing pipe way 8 to be equipped with valve, flowmeter and pressure sensor, sweep pipeline 9 and nitrogen gas tank 53 intercommunication, just it is equipped with the valve to sweep pipeline 9. Specifically, the valve in this embodiment includes a pressure reducing valve, a stop valve, and a pressure relief valve, and performs purging by using nitrogen gas, and the gas supply and distribution line 8 and the purge line 9 are communicated with the gas inlet line 6 through a tee joint. The flow meter and the pressure sensor in the embodiment are respectively used for monitoring the flow and the pressure of helium, and the flow and the pressure of the helium are controlled by using the pressure reducing valve, the stop valve and the pressure reducing valve, so that the system can perform leak detection test on the valve 15 to be tested under different pressures. The gas distribution table 51 is composed of a pressure reducing valve, a stop valve, a pressure release valve, a flow meter, a pressure sensor, and the like.
Wherein, as shown in fig. 3, the vacuum detection platform includes temperature sensor 19, vacuum cover 13, lower base 14, first vacuum pump 3 and second vacuum pump 10, refrigerating plant with the valve 15 that awaits measuring all place in on lower base 14, and by vacuum cover 13 is sealed, first vacuum pump 3 with vacuum cover 13 intercommunication, second vacuum pump 10 and gas outlet pipe 7 intercommunication, temperature sensor 19 locates in the vacuum cover 13, temperature sensor 19 is used for monitoring the temperature of the environment that the valve 15 that awaits measuring is located. Specifically, the vacuum cover 13 ensures that the environment where the valve 15 to be tested is located is isolated from the outside, the valve 15 to be tested can be in the vacuum environment for leak detection test, the lower base 14 is used for connecting the refrigerating device and the valve 15 to be tested, the first vacuum pump 3 controls the pressure environment of the valve 15 to be tested, and the second vacuum pump 10 controls the pressure environment in the air inlet pipeline 6 and the air outlet pipeline 7. Valves or switches are arranged on the first vacuum pump 3 and the second vacuum pump 10 to control the on-off of the pumps. The temperature sensor 19 transmits the monitored temperature signal to an external temperature control system, the external temperature control system controls and adjusts the heating power of the film heater 17 at the bottom of the lower base 14, and then the temperature of the environment where the valve 15 to be detected is located is accurately adjusted, so that the temperature of the valve 15 to be detected and the temperature of the vacuum detection platform can be changed from 20K to 300K.
as shown in fig. 2, the lower base 14 includes a cross-shaped flat plate with three short sides and a long side, the three short sides are provided with grooves, the grooves are connected to the multiple air inlet pipelines 6, and the long side fixes the valve 15 to be measured through a valve connector. Specifically, the short side is welded with the air inlet pipeline 6 through the groove, and the long side fixes the valve 15 to be tested through the valve connecting piece, so that thermal coupling and mechanical coupling are realized. Indium sheets and low-temperature heat-conducting silicone grease used for eliminating thermal contact resistance are arranged among the refrigerating machine cold head, the valve connecting piece and the lower base 14, the lower base 14 is used for transferring cold energy of the refrigerating machine cold head to helium in the air inlet pipeline in a heat conduction mode, the temperature of the refrigerating machine cold head is further reduced to a liquid hydrogen temperature area (about 20K) from a liquid nitrogen temperature area (about 77K) of the precooling device, meanwhile, the cold energy is transferred to the valve 15 to be tested, the temperature of the valve 15 to be tested is cooled to the liquid hydrogen temperature area (about 20K) from normal temperature (about 300K), and the requirement of test temperature is met. One end of the lower base 14, which is far away from the cold head of the refrigerator, is suspended in the vacuum cover 13 through an epoxy resin pull rod to play a supporting role. The lower base 14 of the present embodiment is made of copper, which has a good thermal conductivity. The utility model discloses support quick rewarming and trade a, it is convenient that the sample is changed, and test cycle is short. More than two sets of valve connectors can be provided, and when one set of valve connectors is tested, the other set of valve connectors can be assembled with the next set of samples to be tested in advance. After a group of samples to be detected are tested, the temperature control system is used for quickly rewarming and opening the vacuum cover, another prepared valve connecting piece which is provided with the samples to be detected is quickly replaced, the vacuum cover is installed, the air inlet pipeline and the air outlet pipeline are blown off by high-purity nitrogen, the background concentration of helium is not more than 10e-7 Pa.m 3/s, and then the next group of samples to be detected can be detected.
The valve connecting piece comprises a clamping plate 16 and an upper base 18, the clamping plate 16 fixes the valve 15 to be tested on the lower base 14, and the upper base 18 is buckled on the clamping plate 16. The valve connector can be customized according to the type of the valve to be tested. Indium sheets and low-temperature heat-conducting silicone grease for eliminating thermal contact resistance are arranged among the clamping plate 16, the valve 15 to be tested and the upper base 18; the clamping plate 16 is fixed on the lower base 14 through the upper base 18 and is provided with an indium sheet for eliminating contact thermal resistance and low-temperature heat-conducting silicone grease to realize thermal coupling and mechanical coupling. The clamping plate 16 and the upper base 18 in this embodiment are made of copper, and have good heat conductivity.
Wherein, still include shield cover 12, shield cover 12 install in vacuum cover 13 is inboard, and detain and locate the valve 15 that awaits measuring, vacuum cover 13 have with the opening that first vacuum pump 3 is connected, with the first hole door that inlet line 6 is connected and with the second hole door that outlet line 7 is connected. The shielding case 12 is used for reducing radiation heat leakage of the vacuum cover 13 to the valve 15 to be tested, the upper end of the shielding case is open and connected to a vacuum-pumping pipeline so as to be convenient for vacuum pumping and leakage detection of the valve 15 to be tested, and the side openings of the shielding case are a plurality of hole doors which are used for enabling helium to enter and exit the shielding case 12 through the air inlet pipeline 6 and the air outlet pipeline 7 and are connected with the valve 15 to be tested. The shield 12 is made of oxygen-free copper and is covered with a plurality of layers of heat insulating materials to reduce radiation heat leakage.
The utility model also discloses a valve low temperature leak hunting method, include:
s1, vacuumizing the air inlet pipeline, the air outlet pipeline and the vacuum detection platform at room temperature, and opening a refrigerating device to cool the vacuum detection platform;
S2, opening a valve of an air inlet pipeline and a valve of an air outlet pipeline which are connected with the same valve to be detected and a valve of a second helium mass spectrometer leak detector, closing the valve to be detected, observing the index of the second helium mass spectrometer leak detector, detecting the inner leak rate of the valve to be detected, opening a valve of a first helium mass spectrometer leak detector, observing the index of the first helium mass spectrometer leak detector, and detecting the outer leak rate of the air inlet end of the valve;
S3, according to the step S2, under the condition that the valve to be detected is at different high pressure values, the readings of the first helium mass spectrometer leak detector and the second helium mass spectrometer leak detector are observed, and the valve to be detected is subjected to inner leak rate detection and outer leak rate detection of the air inlet end under different high pressure values;
S4, closing a valve of the air inlet pipeline and a valve of the air outlet pipeline, opening a valve to be tested under the set pressure condition, opening the valve of the air outlet pipeline of the valve to be tested, gradually exhausting and releasing pressure, simultaneously adjusting the opening and closing state of the valve to be tested, observing the index of the first helium mass spectrometer leak detector, and detecting the overall external leak rate of the valve to be tested;
The above is a test method for performing leak detection test on a single valve to be tested, and so on, can be applied to leak detection test of a plurality of valves to be tested: the method comprises the steps of sequentially detecting the inner leakage rate and the air inlet end outer leakage rate of the valve to be detected under the vacuum condition for other valves to be detected according to the step S2, sequentially detecting the inner leakage rate and the air inlet end outer leakage rate of the valve to be detected under different preset pressure conditions according to the step S3, and sequentially detecting the whole outer leakage rate of the valve to be detected according to the step S4. This embodiment does not limit leak hunting test order, and the experimenter can test next after finishing a valve leak hunting test to be tested promptly, also can leak the detection in earlier carrying out leak hunting with a batch of valve leak hunting to be tested, leaks the detection again, leaks the detection outside at the predetermined pressure value finally.
specifically, as shown in fig. 1, before leak detection can begin, the valve under test must be thoroughly degreased and dried because both grease and moisture can become solid at low temperatures, causing wear to the valve components, particularly the sealing surfaces. The testing device is arranged at a ventilation position, and the participants need to make safety protection. And installing a valve to be tested, an air inlet pipeline and an air outlet pipeline, and opening corresponding stop valves to ensure that the pipelines of the valve system are vacuumized at room temperature. And vacuumizing by using a second vacuum pump. Vacuumizing by a mechanical pump for half an hour, and then turning on the molecular pump until the vacuum value is lower than 10e-5Pa. And a blowing method is adopted to be matched with a second helium mass spectrometer leak detector to perform leak detection on the air inlet pipeline and the air outlet pipeline, so that no leakage at the installation joint is ensured. And then, a vacuum detection platform is installed, a first vacuum pump is used for vacuumizing, a blowing method is adopted to cooperate with a first helium mass spectrometer leak detector to perform leak detection on the vacuum detection platform, and the fact that the installation joint is free of leakage is ensured. Closing all valves and openingand (5) cooling the refrigerator. When the valve to be tested is lowered to 20K, the stop valve at the helium source is opened, the pressure reducing valve is adjusted to enable the helium pressure to be 1MPa and the flow to be 2.75e-5And kg/s, injecting liquid nitrogen into the heat exchange cavity. The preparation is completed. In this embodiment, a stop valve is used for a valve for opening and closing the switch, and a pressure reducing valve is used for a valve for reducing pressure.
Specifically, the multiple valves to be tested are subjected to internal leakage rate testing, the corresponding valves of the air inlet pipeline and the air outlet pipeline and the valves of the second helium mass spectrometer leak detector are sequentially opened, and the readings of the second helium mass spectrometer leak detector are observed; and (3) carrying out leakage rate outside the gas inlet end by a plurality of valves to be tested, opening a valve of the first helium mass spectrometer leak detector, and observing the reading of the first helium mass spectrometer leak detector.
the operation that a plurality of valves to be tested are in different high pressure value leak detection tests is as follows: firstly, closing all the valves of the air inlet pipelines, regulating the pressure of helium input by using a pressure reducing valve, sequentially boosting the pressure to 5MPa, 5.5MPa, 6MPa, 7MPa, 9MPa, 10MPa, 13MPa, 15MPa, 17MPa, 19MPa, 20.6MPa and 21MPa, sequentially opening the stop valves of all the air inlet pipelines under each pressure, observing changes and recording the readings of a first helium mass spectrometer leak detector and a second helium mass spectrometer leak detector, and closing the stop valves of all the air inlet pipelines after detection is finished. And if the pipeline pressure exceeds 22MPa, the safety valve is automatically opened to release the pressure. And finishing the detection of the inner leakage rate and the detection of the outer leakage rate of the air inlet end of the first batch of electromagnetic valves under different pressures. And closing the helium source stop valve, closing the second helium mass spectrometer leak detector stop valve, and stopping the second helium mass spectrometer leak detector. Because the test is under pressure, the pipe needs to be made of high pressure resistant material.
The operation of the whole external inspection of a plurality of valves to be tested is as follows: and (3) closing all the valves of the gas outlet pipeline, wherein the pressure of the gas inlet end of each valve is 21MPa, and opening 5 electromagnetic valves to be tested in sequence to perform the whole body external inspection. Opening first solenoid valve and examining outward earlier, opening the valve of the gas outlet pipeline of this solenoid valve, relief valve, the check valve carries out the release exhaust, and the solenoid valve action utilizes a helium mass spectrometer leak detector to inspect whole leakage, and until pressure drop to atmospheric pressure, the leak hunting of first solenoid valve is accomplished, closes the valve of this gas outlet pipeline. And then sequentially opening the valves of the air outlet pipelines of other electromagnetic valves, and carrying out integral external inspection on the other electromagnetic valves according to the integral external inspection method of the first electromagnetic valve.
The embodiment of the utility model provides a valve low temperature leak hunting system utilizes refrigerating plant as the cold source, realizes carrying out the leak hunting test of valve under adjustable low temperature environment, has solved the excessive dependence of valve low temperature leak hunting system to cryogenic liquid among the prior art, leads to the test operation complicated, causes the problem of the extravagant a large amount of raw and other materials as cryogenic liquid; liquid hydrogen is got rid of as a test cold source, so that the safety and reliability of the test are greatly improved; the system complexity is reduced, and the labor cost and the test cost are reduced; meanwhile, the valve low-temperature leakage detection system provided by the utility model also realizes the accurate and controllable sample temperature; a plurality of valves to be tested can be detected in one test, rapid rewarming replacement is supported, the sample is convenient to replace, and the test period is short.
The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention in its corresponding aspects.

Claims (7)

1. A valve low temperature leak detection system, comprising: supply distributing device, refrigerating plant, first helium mass spectrometer leak detector, second helium mass spectrometer leak detector, many air inlet pipelines, many air outlet pipelines and vacuum test platform, refrigerating plant and the valve that awaits measuring all locate vacuum test platform, supply distributing device through the air inlet pipeline with vacuum test platform intercommunication, first helium mass spectrometer leak detector with vacuum test platform intercommunication, second helium mass spectrometer leak detector through air outlet pipeline with vacuum test platform intercommunication, it is every to the air inlet pipeline with the air outlet pipeline is connected respectively and is corresponding the both ends of valve that awaits measuring first helium mass spectrometer leak detector, second helium mass spectrometer leak detector, air inlet pipeline and air outlet pipeline are equipped with the valve respectively.
2. The valve low-temperature leak detection system according to claim 1, further comprising a precooling device, wherein the precooling device comprises a heat exchange cavity, the heat exchange cavity is provided with a medium inlet and a medium outlet, and a coil pipe is formed in the middle section of the air inlet pipeline and extends into the heat exchange cavity to exchange heat with a heat exchange medium in the heat exchange cavity.
3. The valve low-temperature leak detection system according to claim 1, wherein the gas supply and distribution device comprises a gas supply and distribution pipeline and a purging pipeline which are connected in parallel, the gas supply and distribution pipeline is communicated with a helium gas source, the gas supply and distribution pipeline is provided with a valve, a flowmeter and a pressure sensor, the purging pipeline is communicated with a nitrogen gas tank, and the purging pipeline is provided with a valve.
4. The valve low-temperature leak detection system according to claim 1, wherein the vacuum detection platform comprises a temperature sensor, a vacuum cover, a lower base, a first vacuum pump and a second vacuum pump, the refrigeration device and the valve to be detected are placed on the lower base and sealed by the vacuum cover, the first vacuum pump is communicated with the vacuum cover, the second vacuum pump is communicated with an air outlet pipeline, and the temperature sensor is arranged in the vacuum cover.
5. The system of claim 4, wherein the bottom base comprises a cross plate shape with three short sides and a long side, the three short sides are each provided with a slot, the slots are connected with the plurality of air inlet pipelines, and the long side is used for fixing the valve to be tested through a valve connecting piece.
6. The valve low temperature leak detection system of claim 5, wherein the valve connector comprises a clamping plate and an upper base, the clamping plate fixes the valve to be tested on the lower base, and the upper base is buckled on the clamping plate.
7. The valve low-temperature leak detection system according to claim 6, further comprising a shielding cover, wherein the shielding cover is installed inside the vacuum cover and fastened to the valve to be tested, and the vacuum cover has an opening connected to the first vacuum pump, a first aperture connected to the air inlet pipeline, and a second aperture connected to the air outlet pipeline.
CN201920584767.1U 2019-04-26 2019-04-26 Valve low-temperature leakage detection system Withdrawn - After Issue CN209802606U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201920584767.1U CN209802606U (en) 2019-04-26 2019-04-26 Valve low-temperature leakage detection system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201920584767.1U CN209802606U (en) 2019-04-26 2019-04-26 Valve low-temperature leakage detection system

Publications (1)

Publication Number Publication Date
CN209802606U true CN209802606U (en) 2019-12-17

Family

ID=68831141

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201920584767.1U Withdrawn - After Issue CN209802606U (en) 2019-04-26 2019-04-26 Valve low-temperature leakage detection system

Country Status (1)

Country Link
CN (1) CN209802606U (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110082046A (en) * 2019-04-26 2019-08-02 中国科学院理化技术研究所 A kind of valve low temperature leak detection system and leak hunting method

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110082046A (en) * 2019-04-26 2019-08-02 中国科学院理化技术研究所 A kind of valve low temperature leak detection system and leak hunting method
CN110082046B (en) * 2019-04-26 2024-04-19 中国科学院理化技术研究所 Valve low-temperature leakage detection system and leakage detection method

Similar Documents

Publication Publication Date Title
CN110082046B (en) Valve low-temperature leakage detection system and leakage detection method
CN109163857B (en) A kind of high temperature and pressure helium leakage quantitative testing device and detection method
CN101858842B (en) Test method of metal hydride thermal adsorption and desorption of hydrogen cycle life and special device thereof
CN103925759B (en) Wide warm area temperature control thermostat for thermophysical property measurement
CN113188974B (en) High-pressure hydrogen permeation test device and method for liner material of IV-type gas cylinder
CN101858841B (en) Metal hydride thermal adsorption and desorption hydrogen cycling comprehensive test device
CN112285011B (en) High-temperature high-pressure supercritical carbon dioxide flow accelerated corrosion test system and method
WO2020224632A1 (en) Method for testing leakage performance of aerospace composite material member in low temperature environment
CN106932228B (en) Natural hex liquid phase sampling system and method
CN100461039C (en) Automatic control system and method for cyclic test in multiple service positions and at high and low temperatures
CN201497714U (en) Thermal protection test device capable of simulating height and pressure difference environment
CN209802606U (en) Valve low-temperature leakage detection system
CN110068431A (en) A kind of leakage test method of aerospace composite tank at low ambient temperatures
CN110068430A (en) A kind of leakage test method of aerospace composite tank
CN110927039A (en) Device for detecting leakage performance of material in high-low temperature cycle mode and detection method thereof
CN103116086B (en) Equipment and method of rapid life tests of built-in multihole heater
CN107966474B (en) Device for measuring heat conductivity coefficient of block based on steady-state method
CN112730510B (en) Liquid drop radiation heat exchange experimental device and method
CN105973543A (en) Low-temperature testing method for gasket and tool flange for low-temperature testing of gasket
CN110672658B (en) Block porous material heat insulation performance test experiment system and test method suitable for large temperature difference and variable pressure conditions
CN208420648U (en) A kind of cold state electrochemical corrosion test device
CN103884519A (en) Ultralow temperature vacuum heat transfer efficiency test system
CN114923841A (en) Hydrogen embrittlement test environment simulation system and use method thereof
CN114893175A (en) Device and method for evaluating damage of natural gas hydrate reservoir caused by drilling fluid invasion
CN220872081U (en) Novel cold and hot impact equipment for engine test

Legal Events

Date Code Title Description
GR01 Patent grant
GR01 Patent grant
AV01 Patent right actively abandoned

Granted publication date: 20191217

Effective date of abandoning: 20240419

AV01 Patent right actively abandoned

Granted publication date: 20191217

Effective date of abandoning: 20240419

AV01 Patent right actively abandoned
AV01 Patent right actively abandoned