CN114062219B - Breathable film performance test integrated device and operation method thereof - Google Patents
Breathable film performance test integrated device and operation method thereof Download PDFInfo
- Publication number
- CN114062219B CN114062219B CN202111177185.XA CN202111177185A CN114062219B CN 114062219 B CN114062219 B CN 114062219B CN 202111177185 A CN202111177185 A CN 202111177185A CN 114062219 B CN114062219 B CN 114062219B
- Authority
- CN
- China
- Prior art keywords
- pressure
- test
- module
- gas
- membrane
- 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.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 21
- 238000011056 performance test Methods 0.000 title claims description 19
- 238000012360 testing method Methods 0.000 claims abstract description 178
- 239000012528 membrane Substances 0.000 claims abstract description 116
- 238000001514 detection method Methods 0.000 claims abstract description 40
- 230000035699 permeability Effects 0.000 claims abstract description 21
- 238000000926 separation method Methods 0.000 claims abstract description 17
- 238000004891 communication Methods 0.000 claims abstract description 9
- 239000007789 gas Substances 0.000 claims description 123
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 22
- 238000009423 ventilation Methods 0.000 claims description 18
- 230000001276 controlling effect Effects 0.000 claims description 17
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 16
- 230000000087 stabilizing effect Effects 0.000 claims description 15
- 230000009172 bursting Effects 0.000 claims description 13
- 229910002092 carbon dioxide Inorganic materials 0.000 claims description 11
- 239000001569 carbon dioxide Substances 0.000 claims description 11
- 238000012544 monitoring process Methods 0.000 claims description 10
- 238000007789 sealing Methods 0.000 claims description 10
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 6
- 229910052757 nitrogen Inorganic materials 0.000 claims description 6
- 239000001301 oxygen Substances 0.000 claims description 6
- 229910052760 oxygen Inorganic materials 0.000 claims description 6
- 239000012466 permeate Substances 0.000 claims description 6
- 230000001105 regulatory effect Effects 0.000 claims description 6
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 claims description 5
- 229910001882 dioxygen Inorganic materials 0.000 claims description 5
- 230000008569 process Effects 0.000 claims description 5
- 229910001873 dinitrogen Inorganic materials 0.000 claims description 4
- 230000006641 stabilisation Effects 0.000 claims description 4
- 238000011105 stabilization Methods 0.000 claims description 4
- 238000007599 discharging Methods 0.000 claims description 3
- 230000010354 integration Effects 0.000 claims description 3
- 238000011156 evaluation Methods 0.000 abstract description 4
- 238000011158 quantitative evaluation Methods 0.000 abstract description 2
- 239000007788 liquid Substances 0.000 description 4
- 238000005259 measurement Methods 0.000 description 4
- 230000000630 rising effect Effects 0.000 description 3
- 230000000712 assembly Effects 0.000 description 2
- 238000000429 assembly Methods 0.000 description 2
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 239000012510 hollow fiber Substances 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 239000004814 polyurethane Substances 0.000 description 2
- 238000012113 quantitative test Methods 0.000 description 2
- 239000002033 PVDF binder Substances 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000013500 data storage Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 229920006335 epoxy glue Polymers 0.000 description 1
- 235000013305 food Nutrition 0.000 description 1
- 230000002209 hydrophobic effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000011002 quantification Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/08—Investigating permeability, pore-volume, or surface area of porous materials
- G01N15/082—Investigating permeability by forcing a fluid through a sample
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D65/00—Accessories or auxiliary operations, in general, for separation processes or apparatus using semi-permeable membranes
- B01D65/10—Testing of membranes or membrane apparatus; Detecting or repairing leaks
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
- G01L5/14—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for measuring the force of explosions; for measuring the energy of projectiles
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M3/00—Investigating fluid-tightness of structures
- G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
- G01M3/26—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/08—Investigating permeability, pore-volume, or surface area of porous materials
- G01N2015/086—Investigating permeability, pore-volume, or surface area of porous materials of films, membranes or pellicules
Landscapes
- Chemical & Material Sciences (AREA)
- General Physics & Mathematics (AREA)
- Physics & Mathematics (AREA)
- Biochemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Dispersion Chemistry (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention relates to the technical field of separation membrane testing, and provides an air permeable membrane performance testing integrated device and an operation method thereof, wherein the device comprises: the device comprises a component test module, a pressure driving and controlling module connected with the component test module through a pipeline, a gas flow detection module connected with the component test module, and a control system respectively connected with the component test module, the pressure driving and controlling module and the gas flow detection module in a communication way, wherein the component test module comprises: the upper unit is connected with the pressure driving module through a pipeline; the middle unit is offered through-hole and non-through-hole from bottom to top, and the through-hole bottom can be dismantled and connect and twist soon and connect, and connect the membrane module can be dismantled to quick twisting and connect the bottom, and the connecting support pole can be dismantled to non-through-hole's bottom. According to the technical scheme, comprehensive evaluation, quantitative evaluation and higher test accuracy and test efficiency of the internal burst pressure, the air permeability coefficient and the integrity of the membrane can be realized in the same device.
Description
Technical Field
The invention relates to the technical field of separation membrane testing, in particular to an air permeable membrane performance testing integrated device and an operation method of the air permeable membrane performance testing integrated device.
Background
The breathable film is an important branch in the field of separation films, and has wide application in the fields of foods, medicines, biology, environmental protection, chemical industry, water treatment and the like. The performance of the separation membrane is the core for determining the use of the separation membrane, and key parameters of the performance of the ventilation membrane at present mainly comprise the ventilation coefficient, the separation coefficient, the mechanical strength, the integrity and the like. At present, a permeable detection device is generally adopted to detect the integrity of a microporous permeable membrane, and for detecting the gas permeability of the permeable membrane, the gas permeability and the separation coefficient of the separation membrane cannot be effectively and accurately tested due to the relatively simple test equipment; in addition, for the test of mechanical strength, especially internal and external bursting pressure, the inner side is generally used for pressurizing and forcing the membrane to burst, the burst pressure is monitored, and the method side has a certain delay effect on data, namely if a certain defect exists before the separation membrane is completely burst, the method cannot accurately feed back in real time, and is generally suitable for rough test of the burst pressure.
In the related art, CN103063523a discloses a device and a method for testing the burst pressure and the compression pressure of a hollow fiber membrane wire, wherein the burst pressure is determined by recording the pressure change in the whole testing process, but the testing accuracy is low, and the single test is only performed on the burst pressure and the compression pressure, so that the quantitative test on the multiple performances such as the ventilation performance of a gas separation membrane is difficult to realize; CN102798586a discloses a novel test system for micro-ventilation film ventilation test, which uses a liquid lift tube liquid level meter, adopts isobaric liquid to fill the original space after gas is permeated, measures and calculates the rate of gas passing through the micro-ventilation film under a certain pressure difference by recording the liquid inlet speed, and has the advantages of complicated test, poor accuracy and difficulty in realizing quantitative test on the multiple performances of the ventilation film such as bursting pressure, integrity and the like.
Therefore, a new performance testing device for the breathable film needs to be studied to solve the problems of lack of a performance evaluation method for the breathable film, single equipment testing index, low integration level and the like.
Disclosure of Invention
In view of the above, it is necessary to provide an integrated device for testing performance of a breathable membrane and an operation method thereof, which can not only realize rapid and accurate testing of burst pressure in the membrane, but also realize comprehensive evaluation of the permeability coefficient and integrity of the membrane, and can realize quantitative evaluation of multiple performances of the breathable separation membrane.
In order to achieve the above purpose, the present invention adopts the following technical scheme:
an air permeable membrane performance test integrated device, comprising: the device comprises a component test module, a pressure driving control module connected with a top pipeline of the component test module, a gas flow detection module connected with the bottom of the component test module, and a control system respectively connected with the component test module, the pressure driving control module and the gas flow detection module in a communication way, wherein the component test module comprises:
the upper unit is connected with the pressure driving module through a pipeline; the middle unit is provided with a through hole and a non-through hole from bottom to top, the bottom of the through hole is detachably connected with a quick-twist joint, the bottom of the quick-twist joint is detachably connected with a membrane component, and the bottom of the non-through hole is detachably connected with a supporting rod.
Preferably, the upper unit includes: an upper cylinder; the air inlet is arranged on the top surface of the upper cylinder body and is connected with the pressure driving module through a pipeline; the first exhaust port is arranged on the side surface of the upper cylinder body, and a first electromagnetic valve is arranged on an exhaust pipeline connected with the first exhaust port; the air inlet side pressure sensor is connected to the side face of the upper cylinder body, the height of the connecting position of the air inlet side pressure sensor on the upper cylinder body is higher than the height of the first exhaust port, and the air inlet side pressure sensor is in communication connection with the control system.
Preferably, the lower unit comprises: a lower cylinder; the second exhaust port is arranged on the side surface of the lower cylinder body, is connected with the gas flow detection module through a pipeline, and is provided with a second electromagnetic valve on an exhaust pipeline connected with the second exhaust port; and the gas permeation side pressure sensor is connected to the side surface of the lower cylinder body, the height of the connecting position of the gas permeation side pressure sensor on the lower cylinder body is higher than the height of the second exhaust port, and the gas permeation side pressure sensor is in communication connection with the control system.
Preferably, the upper unit, the middle unit and the lower unit are connected in a sealing way through threads and sealing rings, and the upper end and the lower end of the middle unit are sleeved in the upper unit and the lower unit respectively;
the through holes and the non-through holes formed in the middle unit are distributed in a cross manner, two through holes are formed in the through holes, two non-through holes are formed in the through holes, the through holes and the quick screwing connectors are arranged one by one, and the non-through holes and the connecting rods are arranged one by one.
Preferably, the supporting rod is a telescopic adjusting supporting rod, and the length adjusting range of the telescopic adjusting supporting rod is 5cm-15cm; the gas flow detection module is a high-precision gas flowmeter, and the measuring range of the high-precision gas flowmeter is 0-100ml/min.
Preferably, the pressure driving module includes: and the high-pressure gas cylinders are connected in parallel and are respectively connected with the component test module through pipelines, a pressure reducing valve is arranged on each gas outlet connecting pipeline of each high-pressure gas cylinder, and an electric proportional regulating valve is arranged on the connecting pipeline close to the component test module.
The operation method of the ventilation film performance test integrated device comprises the following steps:
installing two ends of a membrane assembly on quick-screwing joints of a middle unit of an assembly test module, adjusting the height of a supporting rod, and straightening down a separation membrane to be uniformly distributed;
the middle unit is tightly screwed and hermetically connected with the upper unit and the lower unit, and the assembly testing module is sequentially connected with the pressure driving and controlling module, the air inlet side pressure sensor, the air outlet side pressure sensor and the air outlet pipeline;
starting a control system, opening a specified high-pressure gas cylinder and a pressure reducing valve thereof after the control system normally operates, and adjusting the test pressure;
setting pre-detection pressure, boosting time and stabilizing time in a constant pressure mode, opening a first electromagnetic valve connected with an upper unit of the component testing module and a second electromagnetic valve connected with a lower unit of the component testing module, controlling boosting, fully discharging air in the device, and then closing the first electromagnetic valve;
after pressure stabilization, monitoring a permeation side pressure through a gas permeation side pressure sensor, and if the monitored permeation side pressure is maintained within a specified pressure range for a specified duration, determining that the membrane assembly is intact and the air tightness of the device is not problematic;
after the control device is depressurized, performing an air permeability coefficient test or a membrane module integrity test or an internal bursting pressure test or sequentially performing an air permeability coefficient test and a membrane module integrity test or sequentially performing an air permeability coefficient test and an internal bursting pressure test or sequentially performing a membrane module integrity test and an internal bursting pressure test or sequentially performing an air permeability coefficient test, a membrane module integrity test and an internal bursting pressure test;
after the test is completed, the data is saved, the pressure is reset, the assembly is removed, and the power supply is turned off.
Preferably, the air permeability coefficient test comprises the steps of:
under a constant pressure mode, setting test pressure, boosting time and stabilizing test time, and controlling to start boosting, wherein the value range of the test pressure is 0.1-0.3 MPa, the value range of the boosting time is 5-10 min, and the stabilizing test time is not less than 30min;
when the pressure is constant, detecting the flow of the permeated gas in real time through a gas flow detection module;
according to the permeate gas flow, calculating the air permeability coefficient according to a preset formula, wherein the preset formula is as follows:
F＝Q/(ΔP·S)，
wherein F is characterized by the permeability coefficient (mL cm -2 ·min -1 ·bar -1 ) Q is characterized by permeate gas flow (ml/min), ΔP is characterized by transmembrane pressure difference (bar), i.e., set test pressure; s is characterized by the effective area (cm) of the membrane 2 )。
Preferably, the membrane module integrity test comprises the steps of:
setting test pressure, boosting time and stabilizing test time under a constant pressure mode, and controlling to start boosting by using a nitrogen high-pressure gas cylinder, wherein the value range of the test pressure is 0.1-0.3 MPa, the value range of the boosting time is 5-10 min, and the stabilizing test time is not less than 30min;
when the pressure is constant, detecting the flow of the permeated nitrogen gas in real time through a gas flow detection module;
after the pressure is relieved, the control device controls the oxygen high-pressure gas cylinder to start up and boost under the same constant pressure mode, and after the pressure is constant, the gas flow rate detection module detects the flow rate of the permeated oxygen gas in real time;
after the pressure is relieved, the control device controls the adoption of a carbon dioxide high-pressure gas cylinder to start up and boost under the same constant pressure mode, and after the pressure is constant, the flow of the permeated carbon dioxide gas is detected in real time through the gas flow detection module;
calculating the ratio between any two of the flow of the permeated nitrogen gas, the flow of the permeated oxygen gas and the flow of the permeated carbon dioxide gas, wherein the ratio is determined by a larger value and a smaller value;
if any ratio is far greater than 1, determining that the integrity of the membrane assembly is good;
if there is a ratio approaching 1, then there is a problem in determining the integrity of the membrane module.
Preferably, the internal burst pressure test comprises the steps of:
setting maximum test pressure, boosting time and controlling starting boosting under the boosting mode;
in the boosting process, the flow of the permeation gas is detected in real time through a gas flow detection module, the test pressure is detected in real time through an air inlet side pressure sensor, and a relation graph of the test pressure and the permeation gas flow is generated;
if the increase value of the permeation gas flow rate in unit time is larger than a preset value, determining that the membrane is broken, stopping boosting, and determining that the maximum value of the test pressure corresponding to the permeation gas flow rate in unit time is the burst pressure in the membrane.
The beneficial effects of the invention are as follows:
(1) The integrated device for testing the performance of the breathable film provided by the invention can be used for rapidly and accurately testing the bursting pressure in the film, and simultaneously comprehensively evaluating the breathability and the integrity of the film, so that the real one-machine multi-purpose device is realized.
(2) The ventilation membrane performance test integrated device provided by the invention has the advantages of simple structure, convenience in use, suitability for testing the relevant performance of PMP membranes, PP separation membranes, PVDF hydrophobic membranes and the like, simplicity in test method, easiness in operation, stable and reliable test structure and high reproducibility.
(3) The ventilation film performance test integrated device provided by the invention is provided with a control system which is in communication connection with each module, has a numerical value real-time on-line monitoring function, and is high in measurement accuracy, and data feedback is timely.
(4) The invention provides an air permeable membrane performance test integrated device, which is provided with a component test module, wherein the component test module comprises an upper unit, a middle unit and a lower unit which are sequentially and hermetically connected from top to bottom, the membrane component is detachably connected to the middle unit, the membrane component is convenient to detach and replace, and meanwhile, the middle unit is provided with a supporting rod, so that the fixation of the membrane component is realized, membrane wires on the membrane component are straightened as much as possible, the membrane wires are uniformly distributed, the measurement accuracy is ensured, and the quantitative comparison is facilitated.
(5) The operation method of the ventilation membrane performance test integrated device provided by the invention realizes the ventilation coefficient test, the membrane assembly integrity test and the internal burst pressure test, realizes the quantification of the performance test, and is more convenient for comprehensively evaluating the membrane performance.
Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.
Drawings
The foregoing and/or additional aspects and advantages of the invention will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:
FIG. 1 shows a schematic structural view of an integrated device for testing performance of a breathable film, according to an embodiment of the invention;
FIG. 2 is a schematic top view of a central unit of a component testing module in an air permeable membrane performance testing integrated device according to an embodiment of the present invention;
FIG. 3 is a schematic view showing the structure of a membrane module at a membrane module mounting position after a module test module is mounted on a membrane module in an air permeable membrane performance test integrated device according to an embodiment of the present invention;
figure 4 shows a schematic structural view of a membrane module according to an embodiment of the invention,
wherein, the correspondence between the reference numerals and the components in fig. 1 to 4 is:
the device comprises a 10-component testing module, a 102 upper unit, a 1022 upper cylinder, a 1024 air inlet, a 1026 first air outlet, a 1028 first electromagnetic valve, a 1030 air inlet side pressure sensor, a 104 middle unit, a 1042 through hole, a 1044 non-through hole, a 1046 quick-screw joint, a 1048 supporting rod, a 106 lower unit, a 1062 lower cylinder, a 1064 second air outlet, a 1066 second electromagnetic valve, a 1068 gas permeation side pressure sensor, a 108 sealing ring, a 20-pressure driving and controlling module, a 202 high-pressure air bottle, a 204 pressure reducing valve, a 206 electric proportional regulating valve, a 30-gas flow monitoring module, a 40-control system, a 50-membrane component and a 502 membrane wire.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be further clearly and completely described in the following in conjunction with the embodiments of the present invention. It should be noted that the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
As shown in fig. 1 to 4, an air permeable membrane performance test integrated device according to an embodiment of the present invention includes: the device comprises a pressure driving control module 20, a component testing module 10, a gas flow detection module and a control system 40, wherein the top of the component testing module 10 is connected with the pressure driving module through a pipeline, the bottom of the component testing module 10 is connected with the gas flow detection module through a pipeline, and the control system 40 is respectively connected with the component testing module 10, the pressure driving module and the gas flow detection module through communication. The component test module 10 includes: the upper unit 102, the middle unit 104 and the lower unit 106 are sequentially and hermetically connected from top to bottom, the upper unit 102 is connected with the pressure driving module through a pipeline, the middle unit 104 is provided with a through hole 1042 and a non-through hole 1044 from bottom to top, the bottom end of the through hole 1042 is detachably connected with a quick-screwing joint 1046, the bottom end of the quick-screwing joint 1046 is detachably connected with the membrane assembly 50, and the bottom end of the non-through hole 1044 is detachably connected with the supporting rod 1048. The membrane module 50 is installed below the middle unit 104 through the quick screwing joint 1046, membrane wires 502 on the membrane module 50 are straightened through the supporting rods 1048, so that the membrane module 50 is uniformly distributed, the membrane module 50 is convenient to test, the membrane module 50 is structurally shown in fig. 4, the membrane wires 502 are sealed by PU (polyurethane) with the diameter of 10mm or 8mm through epoxy glue, then the end faces are cut off, the end face holes of the membrane wires are exposed, the membrane module 50 is formed, through holes 1042 are reserved in the section cutting mode so as to be connected with the quick screwing joint 1046 for air intake, the test module can be conveniently replaced, then the middle unit 104 is in sealing connection with the upper unit 102 and the lower unit 106, the assembly of the module test module 10 is realized, the membrane module 50 is convenient to detach and replace, the membrane wires 502 on the membrane module 50 are uniformly distributed through the supporting rods 1048 as much as possible, the measurement accuracy is ensured, and quantitative comparison is facilitated. The pressure driving and accurate regulation and control of the pressure are realized through the pressure driving and control module 20, the pressure is provided for the component testing module 10, the gas flow detection module is a high-precision gas flowmeter, the measuring range of the high-precision gas flowmeter is 0-100ml/min, under the control of various modes and parameters, the gas flow detection module is used for detecting the permeation gas flow, the size of the permeation side gas flow is accurately measured, data support is provided for each ventilation film performance test, and the quantitative detection of various film performances in the same device is facilitated. The control system 40 is used for controlling the operation of the whole device, realizing the functions of pressure, test time setting, real-time curve monitoring and the like, and can be set into a constant pressure mode and a boost mode, wherein the constant pressure mode is used for pre-detection, air permeability coefficient test and integrity test, and the boost mode is used for internal burst pressure test.
Alternatively, the membrane module 50 may be a flat gas permeable membrane, and may be directly sealed between the upper unit 102 and the lower unit 106.
Further, as shown in fig. 1, the upper unit 102 includes an upper cylinder 1022, an intake port 1024, a first exhaust port 1026, a first solenoid valve 1026, an intake side pressure sensor 1030, and the like. An air inlet 1024 is provided on the top surface of the upper cylinder 1022 and is connected to the pressure driving module by a pipeline, and air is input from the pressure driving module to the component testing module 10 through the air inlet 1024 to provide pressure. The first exhaust port 1026 is disposed on the side of the upper cylinder 1022, and a first electromagnetic valve 1026 is disposed on the exhaust pipe connected thereto, and is opened to exhaust air in the exhaust device when releasing pressure, and the exhaust pipe can be connected to an external gas collecting and processing device to classify different gases. The intake side pressure sensor 1030 is connected to the side of the upper cylinder 1022, and the connection position on the upper cylinder 1022 is higher than the height of the first exhaust port 1026, and the intake side pressure sensor 1030 is communicatively connected to the control system 40, so as to detect the pressure of the intake air, so that the control system 40 can adjust the pressure of the intake air to reach the set test pressure.
In addition, the top surface of the upper cylinder 1022 may be connected to a temperature sensor, which is communicatively connected to the control system 40 to provide temperature data for the gas inside the upper cylinder 1022.
Further, as shown in fig. 1, the lower unit 106 includes: a lower cylinder 1062, a second exhaust port 1064, a second solenoid valve 1066, and a gas permeation side pressure sensor 1068. The second exhaust port 1064 is disposed on the side of the lower cylinder 1062, the second exhaust port 1064 is connected to the gas flow detection module through a pipeline, and a second electromagnetic valve 1066 is disposed on the exhaust pipeline connected to the second exhaust port 1064, and is generally in a normally open state in the testing process, when the testing is completed, the second electromagnetic valve is closed, so that the gas flow monitoring module 30 can conveniently detect the flow of the permeated gas, and meanwhile, the second electromagnetic valve plays a certain role in protecting the gas flow monitoring module 30. The gas permeation side pressure sensor 1068 is connected to the side surface of the lower cylinder 1062, and the height of the connection position on the lower cylinder 1062 is higher than that of the second exhaust port 1064, where the gas permeation side pressure sensor 1068 is communicatively connected to the control system 40, and is used for monitoring the permeation side pressure, pre-checking at the initial stage of device operation, primarily determining whether the membrane module 50 is intact, and whether the device air tightness is not problematic, so that more accurate data can be obtained during the later test, and unnecessary test errors are avoided.
Further, as shown in fig. 1 and fig. 2, the upper unit 102, the middle unit 104 and the lower unit 106 are connected in a sealing manner through threads and a sealing ring 108, and the upper end and the lower end of the middle unit 104 are respectively sleeved into the upper unit 102 and the lower unit 106, so that on one hand, the disassembly is convenient, and on the other hand, the tightness is good, and the air tightness of the device is ensured. The through holes 1042 and the non-through holes 1044 are arranged on the middle unit 104 in a cross shape, wherein the two through holes 1042 and the two non-through holes 1044 are arranged, the through holes 1042 and the quick screwing joints 1046 are arranged one by one, the non-through holes 1044 and the connecting rods are arranged one by one, the stability of the installation and fixation of the membrane module 50 is further ensured, and the smooth performance of the test is further ensured.
Specifically, the through-hole 1042 may be an internally threaded through-hole 1042, and the non-through-hole 1044 may be an internally threaded non-through-hole 1044.
Further, the support rods 1048 are telescopic support rods 1048, and the length adjustment range of the telescopic support rods 1048 is 5cm-15cm, so that the device can adapt to various types of membrane assemblies 50, as shown in fig. 3, the support rods 1048 straighten the membrane wires 502 in the membrane assemblies 50 downwards, so that the membrane wires are uniformly distributed, and the device is convenient for better testing.
Further, as shown in fig. 1, the pressure driving control module 20 includes: the multiple high-pressure gas cylinders 202 arranged in parallel are respectively connected with the pipeline of the component test module 10, for example, three high-pressure gas cylinders 202 can be arranged, nitrogen, oxygen and carbon dioxide are respectively filled in each high-pressure gas cylinder 202, a pressure reducing valve 204 is respectively arranged on a gas outlet connecting pipeline of each high-pressure gas cylinder 202 and used for controlling gas to flow out, and an electric proportional regulating valve 206 is arranged on a connecting pipeline close to the component test module 10 and used for accurately regulating gas pressure, so that accurate gas pressure can be provided for the component test module 10 under the control of the control system 40.
The operation method of the ventilation film performance test integrated device according to the embodiment of the invention comprises the following steps:
s1, respectively installing two ends of a packaged membrane module on a module testing module, installing two ends of the membrane module on a quick-screwing joint of a middle unit of the module testing module, adjusting the height of a supporting rod, and straightening down a separation membrane to be uniformly distributed;
s2, tightly screwing and sealing the middle unit with the upper unit and the lower unit, and sequentially connecting the component testing module with the pressure driving and controlling module, the air inlet side pressure sensor, the air outlet side pressure sensor and the air outlet pipeline;
s3, starting the control system, and after the control system operates normally, opening a specified high-pressure gas cylinder and a pressure reducing valve thereof to adjust the test pressure;
s4, setting pre-detection pressure, boosting time and stabilizing time in a constant pressure mode, opening a first electromagnetic valve connected with an upper unit of the assembly test module and a second electromagnetic valve connected with a lower unit of the assembly test module, controlling boosting, fully discharging air in the device, and then closing the first electromagnetic valve;
s5, after pressure stabilization, monitoring a permeation side pressure through a gas permeation side pressure sensor, and if the permeation side pressure is monitored to be maintained within a specified pressure range for a specified duration, determining that the membrane assembly is intact and the air tightness of the device is not problematic;
specifically, for example, the appointed duration is 5min, the appointed pressure range is 0-3Kpa, the pressure is close to 0, the second electromagnetic valve is in an open state, the pressure of the gas is not suppressed at the lower side, and the gas flows out after being directly detected by the gas flowmeter. That is, after pressure stabilization, the monitored permeate side pressure approaches 0 or fluctuates in a smaller pressure range for 5min, i.e., the membrane module is considered to be intact and the device air tightness is not problematic.
S6, after the control device decompresses, the control device is adjusted to a constant pressure mode, test pressure, boosting time and voltage stabilizing test time are set, boosting is controlled to be started, ventilation coefficient test is carried out, the value range of the test pressure is 0.1MPa-0.3MPa, the value range of the boosting time is 5min-10min, and the voltage stabilizing test time is not less than 30min;
s7, detecting the flow of the permeated gas in real time through a gas flow detection module after the pressure is constant;
according to the flow of the permeation gas, the air permeability coefficient is calculated according to a preset formula, wherein the preset formula is as follows:
F＝Q/(ΔP·S)，
wherein F is characterized by the permeability coefficient (mL cm -2 ·min -1 ·bar -1 ) Q is characterized by permeate gas flow (ml/min), ΔP is characterized by transmembrane pressure difference (bar), i.e., set test pressure; s is characterized by the effective area (cm) of the membrane 2 )；
S8, after the control device is depressurized, the control device is regulated to a constant pressure mode, test pressure, pressure rising time and pressure stabilizing test time are set, and the nitrogen high-pressure gas cylinder is controlled to start pressure rising, so that membrane integrity test is carried out, wherein the value range of the test pressure is 0.1MPa-0.3MPa, the value range of the pressure rising time is 5min-10min, and the pressure stabilizing test time is not less than 30min;
s9, after the control device decompresses, under the same constant pressure mode, controlling the oxygen high-pressure gas cylinder to start boosting, and after the pressure is constant, detecting the flow of the permeated oxygen gas in real time through the gas flow detection module;
s10, after the control device decompresses, under the same constant pressure mode, the control device controls the carbon dioxide high-pressure gas cylinder to start boosting, and after the pressure is constant, the gas flow detection module detects the flow of the permeated carbon dioxide in real time;
s11, calculating the ratio between any two of the flow of the gas passing through nitrogen, the flow of the gas passing through oxygen and the flow of the gas passing through carbon dioxide, wherein the ratio is determined by a larger value and a smaller value;
s12, if any ratio is far greater than 1, determining that the integrity of the membrane module is good, and if the ratio is close to 1, determining that the integrity of the membrane module is problematic;
in particular, if the ratio is greater than 10, it is determined that the membrane assembly has good integrity and the ratio is 0.9-1.1, it is determined that the ratio is approaching 1, the membrane assembly has a problem in integrity,
s13, after the control device decompresses, adjusting to a boosting mode, setting the maximum test pressure, boosting time, controlling starting boosting, and performing internal burst pressure test;
s14, in the boosting process, detecting the flow of the permeation gas in real time through a gas flow detection module, detecting the test pressure in real time through an air inlet side pressure sensor, and generating a relation graph of the test pressure and the permeation gas flow;
s15, if the increase value of the permeation gas flow rate in unit time is larger than a preset value, determining that the membrane is broken, stopping boosting, and determining that the maximum value of the test pressure corresponding to the permeation gas flow rate in unit time is the burst pressure in the membrane;
specifically, for example, the unit time is set to 5s, the preset value is set to 5ml/min,
s16, after the test is completed, the data storage, the pressure resetting, the assembly dismantling and the power supply closing are controlled.
The operation method of the integrated device for testing the performance of the breathable film realizes the detection of the breathable coefficient, the integrity of the film and the burst pressure in the film, quantifies the breathable coefficient, the integrity of the film and the burst pressure in the film, is convenient for the comparison of the performance of the product, and has the advantages of simple detection method, reliable test data and higher accuracy. After the membrane component is installed once, the three performance parameters of air permeability coefficient, membrane integrity and in-membrane bursting pressure can be tested in sequence, so that the testing efficiency is greatly improved, and in actual operation, only one performance parameter or two performance parameters can be tested after the installation and pre-detection are finished, and the in-membrane bursting pressure test needs to be arranged at the end.
In addition, after the control device is depressurized, if gas needs to be replaced, a first electromagnetic valve of an upper unit of the assembly test module is opened, original gas is exhausted through boosting, then the first electromagnetic valve is closed, and a next program is started, so that the detection accuracy is further improved.
The ventilation membrane performance test integrated device and the operation method thereof provided by the invention can not only rapidly and accurately realize the internal burst pressure test of the separation membrane, but also comprehensively evaluate the ventilation performance and the integrity of the separation membrane, thereby realizing real one machine with multiple purposes; the device has the numerical value real-time on-line monitoring function, timely data feedback and high measurement accuracy; the test operation method has great significance for perfecting the current domestic breathable film performance evaluation method, and the device has attractive appearance, convenient disassembly and simple and practical operation method, and can be suitable for research and application of the hollow fiber breathable film technology.
The foregoing examples illustrate only a few embodiments of the invention and are described in detail herein without thereby limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.
Claims (6)
1. An air permeable membrane performance test integrated device, comprising:
the device comprises a component test module, a pressure driving control module connected with a top pipeline of the component test module, a gas flow detection module connected with the bottom of the component test module, and a control system respectively connected with the component test module, the pressure driving control module and the gas flow detection module in a communication way, wherein the component test module comprises:
the upper unit, middle part unit and lower part unit of sealing connection from top to bottom in proper order, the upper unit with pressure drive module passes through the pipe connection, the upper unit includes: an upper cylinder; the air inlet is arranged on the top surface of the upper cylinder body and is connected with the pressure driving module through a pipeline; the first exhaust port is arranged on the side surface of the upper cylinder body, and a first electromagnetic valve is arranged on an exhaust pipeline connected with the first exhaust port; the air inlet side pressure sensor is connected to the side surface of the upper cylinder body, the height of the connecting position of the air inlet side pressure sensor on the upper cylinder body is higher than the height of the first exhaust port, and the air inlet side pressure sensor is in communication connection with the control system;
the middle unit is provided with a through hole and a non-through hole from bottom to top, the bottom end of the through hole is detachably connected with a quick-twist joint, the bottom end of the quick-twist joint is detachably connected with a membrane assembly, and the bottom end of the non-through hole is detachably connected with a supporting rod;
the lower unit includes: a lower cylinder; the second exhaust port is arranged on the side surface of the lower cylinder body, is connected with the gas flow detection module through a pipeline, and is provided with a second electromagnetic valve on an exhaust pipeline connected with the second exhaust port; a gas permeation side pressure sensor connected to the side surface of the lower cylinder, wherein the height of the connection position of the gas permeation side pressure sensor on the lower cylinder is higher than the height of the second exhaust port, and the gas permeation side pressure sensor is in communication connection with the control system;
the upper unit, the middle unit and the lower unit are connected in a sealing way through threads and sealing rings, and the upper end and the lower end of the middle unit are sleeved in the upper unit and the lower unit respectively;
the pressure driving control module includes: the high-pressure gas cylinders are connected in parallel and are respectively connected with the component test module through pipelines, a pressure reducing valve is arranged on a gas outlet connecting pipeline of each high-pressure gas cylinder, and an electric proportional regulating valve is arranged on a connecting pipeline close to the component test module;
the plurality of high-pressure gas cylinders arranged in parallel are respectively filled with different gases, including but not limited to nitrogen, oxygen and carbon dioxide;
the operation method of the ventilation film performance test integrated device comprises the following steps:
installing two ends of a membrane assembly on quick-screwing joints of a middle unit of an assembly test module, adjusting the height of a supporting rod, and straightening down a separation membrane to be uniformly distributed;
the middle unit is tightly screwed and hermetically connected with the upper unit and the lower unit, and the assembly testing module is sequentially connected with the pressure driving and controlling module, the air inlet side pressure sensor, the air outlet side pressure sensor and the air outlet pipeline;
starting a control system, opening a specified high-pressure gas cylinder and a pressure reducing valve thereof after the control system normally operates, and adjusting the test pressure;
setting pre-detection pressure, boosting time and stabilizing time in a constant pressure mode, opening a first electromagnetic valve connected with an upper unit of the component testing module and a second electromagnetic valve connected with a lower unit of the component testing module, controlling boosting, fully discharging air in the device, and then closing the first electromagnetic valve;
after pressure stabilization, monitoring a permeation side pressure through a gas permeation side pressure sensor, and if the monitored permeation side pressure is maintained within a specified pressure range for a specified duration, determining that the membrane assembly is intact and the air tightness of the device is not problematic;
after the control device is depressurized, performing an air permeability coefficient test or a membrane module integrity test or an internal bursting pressure test or sequentially performing an air permeability coefficient test and a membrane module integrity test or sequentially performing an air permeability coefficient test and an internal bursting pressure test or sequentially performing a membrane module integrity test and an internal bursting pressure test or sequentially performing an air permeability coefficient test, a membrane module integrity test and an internal bursting pressure test;
after the test is completed, the data is saved, the pressure is reset, the assembly is removed, and the power supply is turned off.
2. The integrated device for testing the performance of the breathable film according to claim 1, wherein,
the through holes and the non-through holes formed in the middle unit are distributed in a cross manner, two through holes are formed in the through holes, two non-through holes are formed in the through holes, the through holes and the quick screwing connectors are arranged one by one, and the non-through holes and the connecting rods are arranged one by one.
3. The integrated device for testing the performance of the breathable film according to claim 2, wherein,
the support rod is a telescopic adjusting support rod, and the length adjusting range of the telescopic adjusting support rod is 5cm-15cm; the gas flow detection module is a high-precision gas flowmeter, and the measuring range of the high-precision gas flowmeter is 0-100ml/min.
4. The breathable film performance test integration device of claim 1, wherein the breathable coefficient test comprises the steps of:
under a constant pressure mode, setting test pressure, boosting time and stabilizing test time, and controlling to start boosting, wherein the value range of the test pressure is 0.1-0.3 MPa, the value range of the boosting time is 5-10 min, and the stabilizing test time is not less than 30min;
when the pressure is constant, detecting the flow of the permeated gas in real time through a gas flow detection module;
according to the permeate gas flow, calculating the air permeability coefficient according to a preset formula, wherein the preset formula is as follows:
，
wherein F is characterized by the permeability coefficient (mL.cm -2 •min -1 •bar -1 ) Q is characterized by permeate gas flow (ml/min), ΔP is characterized by transmembrane pressure difference (bar), i.e., set test pressure; s is characterized by the effective area (cm) of the membrane 2 ）。
5. The air permeable membrane performance test integration device of claim 1, wherein the membrane assembly integrity test comprises the steps of:
setting test pressure, boosting time and stabilizing test time under a constant pressure mode, and controlling to start boosting by using a nitrogen high-pressure gas cylinder, wherein the value range of the test pressure is 0.1-0.3 MPa, the value range of the boosting time is 5-10 min, and the stabilizing test time is not less than 30min;
when the pressure is constant, detecting the flow of the permeated nitrogen gas in real time through a gas flow detection module;
after the pressure is relieved, the control device controls the oxygen high-pressure gas cylinder to start up and boost under the same constant pressure mode, and after the pressure is constant, the gas flow rate detection module detects the flow rate of the permeated oxygen gas in real time;
after the pressure is relieved, the control device controls the adoption of a carbon dioxide high-pressure gas cylinder to start up and boost under the same constant pressure mode, and after the pressure is constant, the flow of the permeated carbon dioxide gas is detected in real time through the gas flow detection module;
calculating the ratio between any two of the flow of the permeated nitrogen gas, the flow of the permeated oxygen gas and the flow of the permeated carbon dioxide gas, wherein the ratio is determined by a larger value and a smaller value;
if any ratio is far greater than 1, determining that the integrity of the membrane assembly is good;
if there is a ratio approaching 1, then there is a problem in determining the integrity of the membrane module.
6. The breathable film performance test integrated device of claim 1, wherein the implosion pressure test comprises the steps of:
setting maximum test pressure, boosting time and controlling starting boosting under the boosting mode;
in the boosting process, the flow of the permeation gas is detected in real time through a gas flow detection module, the test pressure is detected in real time through an air inlet side pressure sensor, and a relation graph of the test pressure and the permeation gas flow is generated;
if the increase value of the permeation gas flow rate in unit time is larger than a preset value, determining that the membrane is broken, stopping boosting, and determining that the maximum value of the test pressure corresponding to the permeation gas flow rate in unit time is the burst pressure in the membrane.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111177185.XA CN114062219B (en) | 2021-10-09 | 2021-10-09 | Breathable film performance test integrated device and operation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111177185.XA CN114062219B (en) | 2021-10-09 | 2021-10-09 | Breathable film performance test integrated device and operation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114062219A CN114062219A (en) | 2022-02-18 |
| CN114062219B true CN114062219B (en) | 2023-09-26 |
Family
ID=80234481
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111177185.XA Active CN114062219B (en) | 2021-10-09 | 2021-10-09 | Breathable film performance test integrated device and operation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114062219B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114713036B (en) * | 2022-06-10 | 2022-08-26 | 北京先通国际医药科技股份有限公司 | Online filter membrane integrity testing device and method and application thereof |
| CN116297112B (en) * | 2023-05-25 | 2023-09-15 | 上海联风气体有限公司 | Gas permeability detection equipment and detection method for polymer film |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07284637A (en) * | 1994-04-20 | 1995-10-31 | Toshiba Corp | Membrane module system |
| CN103149140A (en) * | 2013-02-22 | 2013-06-12 | 江苏博特新材料有限公司 | Porous media air permeability estimating device |
| CN203694926U (en) * | 2013-12-02 | 2014-07-09 | 中国石油化工股份有限公司 | Membrane component separation performance testing platform |
| CN104020093A (en) * | 2014-05-20 | 2014-09-03 | 中国科学院金属研究所 | Method and device for measuring air permeability of battery diaphragm |
| CN112444471A (en) * | 2020-11-13 | 2021-03-05 | 大连卡瑞博纳科技有限公司 | Full-automatic gas separation membrane permeability testing device and method |
| CN112808016A (en) * | 2021-01-06 | 2021-05-18 | 中国原子能科学研究院 | Membrane module testing device, membrane module testing system and membrane module testing method |
-
2021
- 2021-10-09 CN CN202111177185.XA patent/CN114062219B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07284637A (en) * | 1994-04-20 | 1995-10-31 | Toshiba Corp | Membrane module system |
| CN103149140A (en) * | 2013-02-22 | 2013-06-12 | 江苏博特新材料有限公司 | Porous media air permeability estimating device |
| CN203694926U (en) * | 2013-12-02 | 2014-07-09 | 中国石油化工股份有限公司 | Membrane component separation performance testing platform |
| CN104020093A (en) * | 2014-05-20 | 2014-09-03 | 中国科学院金属研究所 | Method and device for measuring air permeability of battery diaphragm |
| CN112444471A (en) * | 2020-11-13 | 2021-03-05 | 大连卡瑞博纳科技有限公司 | Full-automatic gas separation membrane permeability testing device and method |
| CN112808016A (en) * | 2021-01-06 | 2021-05-18 | 中国原子能科学研究院 | Membrane module testing device, membrane module testing system and membrane module testing method |
Non-Patent Citations (1)
| Title |
|---|
| 高分子选择性透气膜的透气性测定方法的比较;李路平;甘肃工业大学学报(02);第109-112页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114062219A (en) | 2022-02-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN114062219B (en) | Breathable film performance test integrated device and operation method thereof | |
| CN107631973B (en) | Multi-method same-machine testing device for permeability measurement of ultra-low permeability rock sample | |
| CN109632557B (en) | Gas-liquid two-phase saturated coal rock sample experimental device and saturation testing method | |
| CN102527245B (en) | A kind of device, system and method that membrane separating property is tested | |
| CN104406750B (en) | The device for detecting sealability and detection method of a kind of water purification machine | |
| CN110102189A (en) | A kind of high-precision detection device for reverse osmosis membrane | |
| WO2022007916A1 (en) | Online testing method for integrity of sterilizing filter element | |
| CN102590016B (en) | Measurement method of soil moisture characteristic curve measurement device | |
| CN216559591U (en) | Be used for fire hose valve detection device | |
| CN100582711C (en) | Device for testing product air leakage | |
| CN217901489U (en) | Bi-component gas separation testing device | |
| CN209069746U (en) | A kind of high precision low pressure hydraulic pressure test platform | |
| CN107265413B (en) | The system for preparing high-purity nitrogen efficiency for improving membrane separator | |
| CN114486079A (en) | Air tightness detection method of diaphragm | |
| CN220251291U (en) | Ion membrane electrolysis trough leak test detection device | |
| CN110187011B (en) | Simulation experiment device and simulation method for dynamic adsorption and desorption research | |
| CN111307688A (en) | Test system and method for determining cement soil osmotic deformation | |
| CN218180761U (en) | Automatic accurate preparation device of insulating standard oil | |
| CN210645906U (en) | Hollow fiber membrane flux testing device | |
| CN216677754U (en) | Quick accurate check out test set of hollow fiber membrane performance | |
| CN206996308U (en) | Dry filter membrane cartridge test equipment | |
| CN214702702U (en) | Air flow test bed for gas turbine component | |
| CN109520681A (en) | A kind of adjustable leak rate calibration system of multimedium leak rate | |
| CN201348602Y (en) | Carbon rod air permeability testing device | |
| CN205670068U (en) | A kind of water heater or the automatic leakage detection equipment of wall-hung boiler |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |