CN111692089A - Vacuum pump temperature test system and test method - Google Patents
Vacuum pump temperature test system and test method Download PDFInfo
- Publication number
- CN111692089A CN111692089A CN202010518551.2A CN202010518551A CN111692089A CN 111692089 A CN111692089 A CN 111692089A CN 202010518551 A CN202010518551 A CN 202010518551A CN 111692089 A CN111692089 A CN 111692089A
- Authority
- CN
- China
- Prior art keywords
- vacuum pump
- temperature
- controller
- vacuum
- test system
- 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.)
- Granted
Links
- 238000012360 testing method Methods 0.000 title claims abstract description 78
- 238000010998 test method Methods 0.000 title abstract description 3
- 238000000034 method Methods 0.000 claims description 9
- 230000007613 environmental effect Effects 0.000 claims description 5
- 239000000284 extract Substances 0.000 claims description 3
- 230000000694 effects Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000010705 motor oil Substances 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B51/00—Testing machines, pumps, or pumping installations
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
Abstract
The invention relates to a vacuum pump temperature test system and a test method, wherein the test system comprises: the temperature box can be internally provided with one or more vacuum pumps to be tested; the controller is connected with the temperature box and the vacuum pump; the vacuum tank is positioned outside the temperature box and is matched and connected with a vacuum pump in the temperature box, and a pressure control assembly is arranged on an upper pipeline of the vacuum tank; the power supply module is connected with the vacuum pump; the data acquisition module is respectively connected with the vacuum pump, the power supply module and the controller and is connected with the first electromagnetic valve and the second electromagnetic valve on the pipeline; and the control terminal is respectively connected with the temperature box, the controller and the data acquisition module, can acquire the external environment temperature of the temperature box and sends a control signal to the controller. The invention can compile test programs according to different test requirements, so that the vacuum pump temperature cycle test system can be compatible with a plurality of different tests, and can test a plurality of vacuum pumps simultaneously, thereby improving the test efficiency.
Description
Technical Field
The invention relates to the field of vacuum pump testing, in particular to a vacuum pump temperature testing system and a vacuum pump temperature testing method.
Background
At present in car helping hand system, the vacuum pump plays important effect, can improve braking effect, improves the security of auttombilism. However, the automobile vacuum pump is greatly influenced by environmental conditions, particularly in winter, the air temperature in most areas of China is low, and the temperatures of engine oil, a starting transmission, water and the like in an automobile are low.
The existing controller for testing the temperature of the vacuum pump is simple, low in safety and reliability, and incapable of changing a start-stop mode according to the actual environment state without stopping and starting in the using process. Under the harsh environment, the starting point, the set point of stopping point deviation cause the vacuum pump frequently to start or do not shut down, greatly consume vacuum pump life, still cause the vacuum pump to damage easily to the test simulation effect that can't accurate reach needs.
And the controller for testing the temperature of the vacuum pump has single control logic, and only can write a single program aiming at a single test, so that the compatibility cannot be realized.
Disclosure of Invention
In view of the above, it is necessary to provide a vacuum pump temperature testing system and a testing method for solving the problems of the conventional controller for testing the temperature of the vacuum pump.
The invention discloses a vacuum pump temperature test system, which comprises:
the temperature box can be used for placing one or more vacuum pumps to be tested;
the controller is connected with the temperature box, can adjust the temperature in the temperature box and is also connected with the vacuum pump;
the vacuum tank is positioned outside the temperature box and is matched and connected with a vacuum pump in the temperature box, and a pressure control assembly is arranged on an upper pipeline of the vacuum tank;
the power supply module is connected with the vacuum pump;
the data acquisition module is respectively connected with the vacuum pump, the power supply module and the controller, can acquire voltage and current data outside the temperature box, and is respectively connected with the first electromagnetic valve and the second electromagnetic valve on the pipeline;
and the control terminal is respectively connected with the temperature box, the controller and the data acquisition module, can acquire the external environment temperature of the temperature box and sends a control signal to the controller.
In one embodiment, the air inlet of the vacuum pump is provided with a high-temperature-resistant air inlet hose, the vacuum pump is connected with the vacuum tank through the air inlet hose, and the air inlet hose is provided with a one-way valve.
In one embodiment, the pressure control assembly includes a first solenoid valve connected to a vacuum tank, a throttle valve, and a pressure gauge.
In one embodiment, the air outlet of the vacuum pump is communicated with the outside of the temperature box through a high-temperature resistant hose.
In one embodiment, the test system comprises one or more self-locking quick plugs, and the second solenoid valve is connected with the vacuum pump through the self-locking quick plugs.
In one embodiment, the data acquisition module includes a pressure sensor.
The invention also discloses a vacuum pump temperature testing method, which comprises the following steps:
s1, synchronously starting a control terminal, a power supply module and a data acquisition module;
s2, the control terminal sends a control signal to the controller according to the temperature box environment temperature acquired by the data acquisition module, and the controller adjusts the temperature box environment temperature according to the test requirement;
and S3, when the ambient temperature of the temperature box reaches the preset temperature for starting the vacuum pump, the control terminal sends a starting control signal to the vacuum pump through the controller, and judges the starting and stopping modes required by the vacuum pump in the current ambient temperature area according to the acquired ambient temperature of the temperature box so as to control the vacuum pump to normally operate.
In one embodiment, before step S1, the method further includes:
s0. setting circulation mode of the temperature box according to the test requirement, and setting a controller to control the vacuum pump to have different start-stop modes in different environmental temperature zones.
In one embodiment, in step S3, the step of operating the vacuum pump includes:
s31, after the vacuum pump extracts air in the vacuum tank through the one-way valve to reach a preset value, the control terminal controls the vacuum pump to stop working through the controller;
s32, the control terminal cuts off a second electromagnetic valve connected with the data acquisition module through the controller to prevent the vacuum tank from returning air and sucking back;
s33, returning air to the vacuum tank through a throttle valve, and collecting air pressure of the vacuum tank through a pressure gauge;
and S34, after the return air reaches a preset value, opening a first electromagnetic valve by a controller to block the return air of the vacuum tank.
In one embodiment, step S33 further includes:
and S331, when the air pressure exceeds a preset value, the test system sends out an alarm signal.
According to the vacuum pump temperature testing system and the testing method, the testing program can be compiled according to different testing requirements, so that the vacuum pump temperature cycle testing system can be compatible with a plurality of different tests, and a plurality of vacuum pumps can be tested simultaneously, and the testing efficiency is improved.
Drawings
FIG. 1 is a block diagram of a vacuum pump temperature testing system in one embodiment;
FIG. 2 is a flow chart of a method for testing the temperature of a vacuum pump according to one embodiment.
Description of reference numerals:
1: a control terminal; 2: a power supply module; 3: a data acquisition module; 4: a temperature box; 5: a vacuum pump; 6: a controller; 7: a vacuum pump; 8: a voltage feedback line; 9: a power line; 10: a pressure gauge; 11: a first solenoid valve; 12: a throttle valve; 13: a second battery valve; 14: self-locking and quick insertion; 15: a one-way valve.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
It will be understood that the terms "first," "second," and the like as used herein may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, a first solenoid valve may be referred to as a second solenoid valve, and similarly, a second solenoid valve may be referred to as a first solenoid valve, without departing from the scope of the present application.
FIG. 1 is a block diagram of a vacuum pump temperature testing system in one embodiment, as shown. The utility model provides a vacuum pump temperature test system, test system includes control terminal 1, power module 2, data acquisition module 3, temperature box 4, vacuum tank 5, controller 6 and vacuum pump 7.
In one embodiment, one or more vacuum pumps 7 to be tested may be placed within the temperature box 4.
Wherein, the air inlet of each vacuum pump 7 is provided with a high-temperature resistant air inlet hose, and the vacuum pump 7 is connected with the vacuum tank 5 through the air inlet hose.
A check valve 15 is arranged in an air inlet hose of the vacuum pump 7, so that the back suction and the reverse rotation of the vacuum pump 7 caused by pressure difference after the operation of the vacuum pump 7 is finished can be avoided.
A high temperature resistant hose is arranged at the air outlet of the vacuum pump 7 and communicated with the outside of the temperature box 4 through the high temperature resistant hose of the air outlet, so that the air in the temperature box 4 is prevented from being damaged by abrasion caused by the vacuum pump 7 in the operation process.
A second electromagnetic valve 14 is arranged on a pipeline connecting the vacuum pump 7 and the vacuum tank 5. In the conventional test system, a vacuum pump 7 corresponds to a vacuum tank 5, which results in that the air pressure cannot be stopped immediately at a set value. In the present invention, a plurality of vacuum pumps 7 and a large-capacity vacuum pump 5 are adopted for matching test, and a first electromagnetic valve 11 and a throttle valve 12 are added to an upper pipeline of the vacuum tank 5. The throttle valve 12 is provided to slow down the return air speed of the vacuum tank, so that when the pressure gauge 10 detects that the pressure of the vacuum tank 5 reaches a preset value, the first electromagnetic valve 11 will cut off the passage, and the air pressure in the vacuum tank 5 can be effectively controlled within a required range.
Furthermore, a self-locking quick plug 14 connected with the electromagnetic valve 13 is arranged on a pipeline for connecting the vacuum tank 5 and the vacuum pump 7, and the self-locking quick plug 14 is a connecting piece and is used for quickly connecting pipelines of various gases in various pneumatic and hydraulic pipelines. The principle is that spring sealing cores are arranged at two ends of the double-seal self-sealing device is characterized in that when.
In one embodiment, the controller 6 is connected to the temperature chamber 4, and can adjust the temperature in the temperature chamber 4, and the controller 6 is also connected to the vacuum pump 7. The controller is internally provided with a circuit board, and can control the vacuum pump 7 by programming according to the test requirements, such as: before the test system is started, a temperature circulation mode of the temperature box 4 is set according to test requirements, and a vacuum pump is set to have different start-stop modes in different environmental temperature regions.
In one embodiment, the vacuum tank 5 is located outside the temperature box 4 and is connected with a vacuum pump inside the temperature box 4, and the upper pipeline of the vacuum tank 5 is provided with a pressure control assembly. The pressure control assembly includes a pressure gauge 10, a first solenoid valve 11, and a throttle valve 12.
In one embodiment, the power module 2 is connected with the vacuum pump 7, one output of the power module 2 is a voltage feedback line 8, the other output is a power line 9, and the power module 2 is connected with the vacuum pump 7 through the voltage feedback line 8 and the power line 9 to realize that each vacuum pump 7 is controlled by a uniform power supply, so that a plurality of vacuum pump test samples are simultaneously performed, the test cycle time is obviously reduced, and the test requirement of simultaneously starting to be completed at the same time can be met.
In one embodiment, the data acquisition module 3 is connected to the power module 2 and the controller 6, respectively. The data acquisition module 3 provides a voltage interface, a current interface, an electromagnetic valve interface and a relay interface. The voltage interface of the data acquisition module 3 is connected with the voltage feedback line 2, the current interface is connected with the power line 9, the electromagnetic valve interfaces are respectively connected with the first electromagnetic valve 11 and the second electromagnetic valve 13, and the relay interface is connected with the relay switch of the vacuum pump 7. The data acquisition module can acquire voltage and current data outside the temperature box and can electrically control the on-off of the first electromagnetic valve 11 and the second electromagnetic valve 13. The data acquisition module 3 may be a pressure sensor.
In one embodiment, the control terminal 1 is respectively connected with the temperature box 4, the controller 6 and the data acquisition module 3. The control terminal 1 can be a PC terminal and can be connected with the temperature box 4, the controller 6 and the data acquisition module 3 in a wireless communication mode. The control terminal 1 can read the data acquisition module 3 and acquire the external environment temperature data of the temperature box, and send a control instruction to the controller 6 according to the test requirement, and the controller 6 controls the vacuum pump 7 to operate so as to realize the test requirement.
FIG. 2 is a flow chart of a method for testing the temperature of a vacuum pump according to an embodiment, as shown. In one embodiment, the invention also discloses a vacuum pump temperature testing method, which comprises the following steps:
s0. setting circulation mode of the temperature box according to the test requirement, and setting a controller to control the vacuum pump to have different start-stop modes in different environmental temperature zones. The program arranged in the controller can be written according to different requirements, so that the vacuum pump temperature cycle test system can be compatible with a plurality of different tests.
S1, synchronously starting a control terminal, a power supply module and a data acquisition module.
And S2, the control terminal sends a control signal to the controller according to the ambient temperature of the temperature box acquired by the data acquisition module, and the controller adjusts the ambient temperature of the temperature box according to the test requirement.
And S3, when the ambient temperature of the temperature box reaches the preset temperature for starting the vacuum pump, the control terminal sends a starting control signal to the vacuum pump through the controller, and judges the starting and stopping modes required by the vacuum pump in the current ambient temperature area according to the acquired ambient temperature of the temperature box so as to control the vacuum pump to normally operate. Wherein, the step of normal operation of vacuum pump includes:
and S31, after the vacuum pump extracts air in the vacuum tank through the one-way valve to reach a preset value, the control terminal controls the vacuum pump to stop working through the controller.
And S32, the control terminal cuts off a second electromagnetic valve connected with the data acquisition module through the controller so as to prevent the vacuum tank from returning air and reversely sucking.
S33, returning air to the vacuum tank through a throttle valve, and collecting air pressure of the vacuum tank through a pressure gauge.
And S331, when the air pressure exceeds a preset value, the test system sends out an alarm signal so as to remind a tester to check the problem in real time.
And S34, after the return air reaches a preset value, opening a first electromagnetic valve by a controller to block the return air of the vacuum tank.
The conventional test system needs to manually start the next cycle after each test cycle is finished. The test system is communicated with the temperature box through the control terminal, so that the test system can more accurately issue required control instructions to the vacuum pump according to the current environment.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. A vacuum pump temperature test system, the test system comprising:
the temperature box can be used for placing one or more vacuum pumps to be tested;
the controller is connected with the temperature box, can adjust the temperature in the temperature box and is also connected with the vacuum pump;
the vacuum tank is positioned outside the temperature box and is matched and connected with a vacuum pump in the temperature box, and a pressure control assembly is arranged on an upper pipeline of the vacuum tank;
the power supply module is connected with the vacuum pump;
the data acquisition module is respectively connected with the vacuum pump, the power supply module and the controller, can acquire voltage and current data outside the temperature box, and is respectively connected with the first electromagnetic valve and the second electromagnetic valve on the pipeline;
and the control terminal is respectively connected with the temperature box, the controller and the data acquisition module, can acquire the external environment temperature of the temperature box and sends a control signal to the controller.
2. A vacuum pump temperature test system as claimed in claim 1, wherein the air inlet of the vacuum pump is provided with a high temperature resistant air inlet hose, the vacuum pump is connected with the vacuum tank through the air inlet hose, and the air inlet hose is provided with a one-way valve.
3. A vacuum pump temperature test system according to claim 1, wherein the pressure control assembly comprises a first solenoid valve connected to a vacuum tank, a throttle valve and a pressure gauge.
4. A vacuum pump temperature test system as claimed in claim 1, wherein the vacuum pump air outlet is communicated with the outside of the temperature box through a high temperature resistant hose.
5. A vacuum pump temperature test system according to claim 3, wherein the test system comprises one or more self-locking quick plugs, and the second solenoid valve is connected with the vacuum pump through the self-locking quick plugs.
6. A vacuum pump temperature test system according to claim 1, wherein the data acquisition module comprises a pressure sensor.
7. A testing method based on the vacuum pump temperature testing system of any one of claims 1-5, characterized in that the testing method comprises the following steps:
s1, synchronously starting a control terminal, a power supply module and a data acquisition module;
s2, the control terminal sends a control signal to the controller according to the temperature box environment temperature acquired by the data acquisition module, and the controller adjusts the temperature box environment temperature according to the test requirement;
and S3, when the ambient temperature of the temperature box reaches the preset temperature for starting the vacuum pump, the control terminal sends a starting control signal to the vacuum pump through the controller, and judges the starting and stopping modes required by the vacuum pump in the current ambient temperature area according to the acquired ambient temperature of the temperature box so as to control the vacuum pump to normally operate.
8. The method for testing the temperature test system of the vacuum pump according to claim 6, wherein before the step S1, the method further comprises:
s0. setting circulation mode of the temperature box according to the test requirement, and setting a controller to control the vacuum pump to have different start-stop modes in different environmental temperature zones.
9. A method for testing a vacuum pump temperature testing system according to claim 7, wherein in step S3, the step of operating the vacuum pump comprises:
s31, after the vacuum pump extracts air in the vacuum tank through the one-way valve to reach a preset value, the control terminal controls the vacuum pump to stop working through the controller;
s32, the control terminal cuts off a second electromagnetic valve connected with the data acquisition module through the controller to prevent the vacuum tank from returning air and sucking back;
s33, returning air to the vacuum tank through a throttle valve, and collecting air pressure of the vacuum tank through a pressure gauge;
and S34, after the return air reaches a preset value, opening a first electromagnetic valve by a controller to block the return air of the vacuum tank.
10. A method for testing a vacuum pump temperature test system according to claim 9, wherein the step S33 further comprises:
and S331, when the air pressure exceeds a preset value, the test system sends out an alarm signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010518551.2A CN111692089B (en) | 2020-06-09 | Vacuum pump temperature testing system and testing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010518551.2A CN111692089B (en) | 2020-06-09 | Vacuum pump temperature testing system and testing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111692089A true CN111692089A (en) | 2020-09-22 |
| CN111692089B CN111692089B (en) | 2024-09-03 |
Family
ID=
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113820069A (en) * | 2021-11-25 | 2021-12-21 | 北京晨晶电子有限公司 | Auxiliary device and method for testing stability of capacitive vacuum gauge |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202502025U (en) * | 2012-02-29 | 2012-10-24 | 中国矿业大学(北京) | Device for high pressure isothermal absorption experiment of coal |
| CN203717314U (en) * | 2014-01-22 | 2014-07-16 | 北京汽车新能源汽车有限公司 | Test system for electric vacuum pump of electric vehicle braking system |
| US20140376586A1 (en) * | 2012-02-27 | 2014-12-25 | Freescale Semiconductor, Inc. | Multi-chip device with temperature control element for temperature calibration |
| CN105911091A (en) * | 2016-05-31 | 2016-08-31 | 中国工程物理研究院总体工程研究所 | Test device and method for research of temperature field distribution characteristics under temperature-acceleration environment |
| CN206158987U (en) * | 2016-10-28 | 2017-05-10 | 安徽江淮汽车集团股份有限公司 | Vacuum pump performance testing system |
| CN212615305U (en) * | 2020-06-09 | 2021-02-26 | 上海拓绅汽车电子有限公司 | Vacuum pump temperature test system |
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20140376586A1 (en) * | 2012-02-27 | 2014-12-25 | Freescale Semiconductor, Inc. | Multi-chip device with temperature control element for temperature calibration |
| CN202502025U (en) * | 2012-02-29 | 2012-10-24 | 中国矿业大学(北京) | Device for high pressure isothermal absorption experiment of coal |
| CN203717314U (en) * | 2014-01-22 | 2014-07-16 | 北京汽车新能源汽车有限公司 | Test system for electric vacuum pump of electric vehicle braking system |
| CN105911091A (en) * | 2016-05-31 | 2016-08-31 | 中国工程物理研究院总体工程研究所 | Test device and method for research of temperature field distribution characteristics under temperature-acceleration environment |
| CN206158987U (en) * | 2016-10-28 | 2017-05-10 | 安徽江淮汽车集团股份有限公司 | Vacuum pump performance testing system |
| CN212615305U (en) * | 2020-06-09 | 2021-02-26 | 上海拓绅汽车电子有限公司 | Vacuum pump temperature test system |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113820069A (en) * | 2021-11-25 | 2021-12-21 | 北京晨晶电子有限公司 | Auxiliary device and method for testing stability of capacitive vacuum gauge |
| CN113820069B (en) * | 2021-11-25 | 2022-03-11 | 北京晨晶电子有限公司 | Auxiliary device and method for testing stability of capacitive vacuum gauge |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101587027A (en) | System for testing heat-transfer performance of gas-water-oil heat interchanger | |
| CN106644451B (en) | Performance detection equipment for exhaust auxiliary brake valve for vehicle and working method thereof | |
| CN106014957A (en) | Test system and test method for vehicle-mounted sliding vane type air compressors | |
| CN103306965A (en) | Performance detection system for automotive electronic fuel pump | |
| CN205135807U (en) | Fuel tank evaporation discharge system equipment | |
| CN111189596A (en) | Gas relay sealing performance testing device and testing method | |
| CN113137409A (en) | Electromagnetic reversing valve test method in ultrahigh pressure environment | |
| CN113250947A (en) | Fuel cell air compressor durability test system and method | |
| CN113339309A (en) | Fuel cell air compressor testing system and method | |
| CN212615305U (en) | Vacuum pump temperature test system | |
| CN109237748A (en) | A kind of hydrojet control method, device and air conditioner | |
| CN201126395Y (en) | Gas cylinder valve air tightness test system | |
| CN111692089A (en) | Vacuum pump temperature test system and test method | |
| CN111692089B (en) | Vacuum pump temperature testing system and testing method | |
| CN111365615B (en) | Valve static pressure life automatic testing device based on gasification pressurization | |
| RU138285U1 (en) | STAND FOR TESTING TURBOCHARGERS OF INTERNAL COMBUSTION ENGINES | |
| CN111076907A (en) | Device for testing sealing performance, pressure resistance and opening pressure of automobile electromagnetic valve | |
| CN107830013B (en) | Marine hydraulic control unit test system and oil way control method | |
| CN110726547A (en) | Portable comprehensive checking device for pressure protection device | |
| CN210834055U (en) | Valve leakage water-free detection system | |
| CN211452829U (en) | Multifunctional valve detection system | |
| CN211527735U (en) | Gas relay sealing performance test device | |
| CN211121956U (en) | Portable comprehensive checking device for pressure protection device | |
| CN210604898U (en) | Self-made piezodensity relay checking device | |
| CN209992129U (en) | Ship stern shaft sealing vacuum tester |
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 |