CN110939572A - Control method of dry-type screw vacuum pump - Google Patents
Control method of dry-type screw vacuum pump Download PDFInfo
- Publication number
- CN110939572A CN110939572A CN201911170900.XA CN201911170900A CN110939572A CN 110939572 A CN110939572 A CN 110939572A CN 201911170900 A CN201911170900 A CN 201911170900A CN 110939572 A CN110939572 A CN 110939572A
- Authority
- CN
- China
- Prior art keywords
- vacuum pump
- controlling
- screws
- dry
- nitrogen
- 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
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C25/00—Adaptations of pumps for special use of pumps for elastic fluids
- F04C25/02—Adaptations of pumps for special use of pumps for elastic fluids for producing high vacuum
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
- F04C28/08—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids characterised by varying the rotational speed
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
- F04C28/28—Safety arrangements; Monitoring
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
- F04C29/0092—Removing solid or liquid contaminants from the gas under pumping, e.g. by filtering or deposition; Purging; Scrubbing; Cleaning
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
- F04C29/04—Heating; Cooling; Heat insulation
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
- F04C29/04—Heating; Cooling; Heat insulation
- F04C29/042—Heating; Cooling; Heat insulation by injecting a fluid
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Applications Or Details Of Rotary Compressors (AREA)
Abstract
The invention discloses a control method of a dry-type screw vacuum pump, which comprises the following steps: self-checking, starting and heating, namely increasing the temperature in the pump through a conductor and keeping the temperature until the work of the vacuum pump is finished; a standby step, maintaining the slow rotation speed of the screw and keeping the screw in an idle state; starting, namely opening an air valve, and controlling current to increase the rotating speeds of the two screws to the target rotating speed; in the working process, nitrogen is introduced into the motor chamber through the nitrogen valve, so that the pressure value of the motor chamber is 1.2-1.5 atmospheres, the positive pressure is prevented from explosion, and the pressure of the motor chamber is ensured to be smaller than the pressure of the working chamber. The invention has the following beneficial effects: the forward explosion prevention is carried out by adopting inert gases such as nitrogen and the like, so that the requirement of special industries on explosion prevention control is met; the heating control solves the problem of unreasonable influence caused by the existing air input with moisture; the controlled use of the shaft angle encoder ensures the reliability of the system.
Description
Technical Field
The invention relates to pumps, in particular to a control method of a dry vacuum pump.
Background
Most of the mechanical vacuum pumps used in the vacuum industry use oil, water or other polymers as the working medium of the pump, and perform various functions such as cooling, sealing, lubricating and the like in the pump. With the development of scientific technology and the expansion of vacuum application field, two problems which need to be solved urgently appear in the original mechanical vacuum pump and the air exhaust system formed by the same: one is that the return of the working medium from the pump contaminates the extraction vessel, and this return affects the quality and quantity of the product in many cases, increasing the maintenance costs of the equipment. Secondly, the medium in the vacuum pump is seriously deteriorated due to the reaction substances in some process procedures, so that the pump cannot work normally. Therefore, the dry mechanical vacuum pump is capable of perfectly solving the technical problems.
The dry vacuum pump is a mechanical vacuum pump which can start pumping from atmospheric pressure and directly discharge pumped bodies to the atmosphere, no oil or other working media exist in a pump cavity, and the limit pressure of the pump is the same magnitude as or close to that of an oil-sealed vacuum pump. The dry screw vacuum pump is one kind of dry vacuum pump, and is one air pumping equipment with air sucking and exhausting functions produced by the synchronous high speed reverse rotation of one pair of screws inside the pump casing. Such as the techniques disclosed in chinese patent No. cn201910363238.x, 201811504692.8.
Therefore, the dry screw vacuum pump can be used for pumping out gas containing a large amount of water vapor and a small amount of dust, has higher ultimate vacuum and lower power consumption, and has the advantages of energy conservation, maintenance-free property and the like.
However, when the dry screw vacuum pump is applied to the chemical industry and the pharmaceutical industry, the explosion-proof control method is on schedule.
Disclosure of Invention
The invention aims to overcome the defects in the prior art and provides a control method of a dry-type screw vacuum pump.
The purpose of the invention is realized by the following technical scheme:
a control method of a dry screw vacuum pump comprises the following steps:
self-checking, namely determining that all valves are in a closed state and ensuring that the pressure value in the pump is 0.8-0.9 atmospheric pressure;
starting, namely controlling a frequency converter to output current to a motor for controlling the rotation of the screws, enabling the two screws to simultaneously start to rotate slowly at the same speed for 2 minutes, and detecting a gap between the two screws;
heating, namely increasing the temperature in the pump through the electric conductor and keeping the temperature until the work of the vacuum pump is finished;
a standby step, maintaining the slow rotation speed of the screw and keeping the screw in an idle state;
starting, namely opening an air valve, controlling current to increase the rotating speed of the two screws to a target rotating speed, and starting to work; in the working process, nitrogen is introduced into the motor chamber through the nitrogen valve, so that the pressure value of the motor chamber is 1.2-1.5 atmospheres, the positive pressure is prevented from explosion, and the pressure of the motor chamber is ensured to be smaller than the pressure of the working chamber.
Preferably, the gap between the two screws is detected by a rotary shaft angle encoder.
Preferably, the slow turning speed is 500 rpm.
Preferably, when the clearance between the two screws is deviated, a fine adjustment step is further included, and the rotating speeds of the two screws are ensured to be consistent.
Preferably, the temperature in the pump is heated to 60 degrees.
Preferably, the motor is a synchronous motor.
Preferably, the method further comprises the step of cleaning,
after the vacuum pump works, introducing a cleaning solvent into the pump to clean the working cavity;
compressed air is introduced to blow dry the working cavity;
and introducing nitrogen into the working cavity through a nitrogen valve to replace the air in the cavity.
Preferably, the method also comprises a cooling step,
when the vacuum pump works, the cooling water inlet valve and the cooling water outlet valve are continuously opened, and the whole working cavity is continuously cooled.
Also comprises a step of alarming, such as alarming,
and when the fact that the water vapor in the working cavity exceeds a preset value is detected, controlling the frequency converter to output current to reduce the screw to a slow rotation speed, and giving an alarm.
Preferably, the nitrogen is replaced by another inert gas.
The invention has the following beneficial effects: the forward explosion prevention is carried out by adopting inert gases such as nitrogen and the like, so that the requirement of special industries on explosion prevention control is met; the heating control solves the problem of unreasonable influence caused by the existing air input with moisture; the controlled use of the shaft angle encoder ensures the reliability of the system.
Drawings
The technical scheme of the invention is further explained by combining the accompanying drawings as follows:
FIG. 1: the invention discloses a schematic three-dimensional view of a dry screw vacuum pump.
Detailed Description
The present invention will be described in detail below with reference to specific embodiments shown in the drawings. These embodiments are not intended to limit the present invention, and structural, methodical, or functional changes that may be made by one of ordinary skill in the art in light of these embodiments are intended to be within the scope of the present invention.
The present invention is not limited to the above embodiments, and structural, methodological, or functional changes made by those skilled in the art according to the embodiments are included in the scope of the present invention.
The invention discloses a control method of a dry-type screw vacuum pump, which comprises the following steps:
self-checking, namely determining that all valves are in a closed state and ensuring that the pressure value in the pump is 0.8-0.9 atmospheric pressure;
starting, namely controlling a frequency converter to output current to a motor for controlling the rotation of the screws, enabling the two screws to simultaneously start to rotate slowly at the same speed for 2 minutes, and detecting a gap between the two screws; the slow turning speed is 500 revolutions per minute;
heating, namely increasing the temperature in the pump through a conductor to enable the temperature in the pump to reach 60 ℃, and keeping the temperature until the work of the vacuum pump is finished;
a standby step, maintaining the slow rotation speed of the screw and keeping the screw in an idle state;
starting, namely opening an air valve, controlling current to increase the rotating speed of the two screws to a target rotating speed, and starting to work; in the working process, nitrogen is introduced into the motor chamber through the nitrogen valve, so that the pressure value of the motor chamber is 1.2-1.5 atmospheres, the positive pressure is prevented from explosion, and the pressure of the motor chamber is ensured to be smaller than the pressure of the working chamber.
Specifically, because of the numerous valves of the dry screw vacuum pump, the valves are checked one by one in the self-checking process. In the starting step, the gap between the two screws is detected by a rotary shaft angle encoder. When the clearance between the two screws has deviation, the method also comprises a fine adjustment step, so that the rotating speeds of the two screws are ensured to be consistent.
The rotary shaft angle encoder converts mechanical quantities such as angular displacement and angular speed of the screws into corresponding electric pulses through photoelectric conversion and outputs the electric pulses as digital quantities, so that the rotating speeds of the two screws are ensured to be consistent, and when the two screws have deviation, the two screws are controlled to be consistent through the frequency converter.
In the heating step, after the temperature in the pump reaches 60 ℃, the liquid in the pump can be gasified originally in the low-pressure environment in the pump, and the liquid is prevented from being left when the vacuum pump works.
In the invention, the motor is a synchronous motor; since its power factor is adjustable.
In the working process, the pressure of the motor chamber is ensured to be smaller than the pressure of the working chamber, which is the key point of the invention, nitrogen is used in the working chamber to perform positive pressure explosion prevention, so that the screw rod in the working chamber rotates to perform air compression, and the compressed air is discharged out of the chamber, thereby realizing the vacuum pumping of the product. While nitrogen is primarily explosion proof, it is ensured that it does not enter the working chamber. The nitrogen gas is discharged out of the cavity along with the compressed air to a greater or lesser extent, so that the nitrogen gas must be uniformly introduced into the motor chamber during the working process.
The invention also comprises the following cleaning steps:
as shown in fig. 1, after the vacuum pump finishes working, a cleaning solvent is introduced into the pump to clean the working chamber;
opening a compressed air valve 1, and introducing compressed air to blow dry a working cavity 5;
the nitrogen valve 2 is opened to introduce nitrogen into the working chamber to replace the air in the chamber, and the nitrogen is replaced by other inert gases, such as helium, argon and the like.
The invention also comprises a cooling step:
when the vacuum pump works, the cooling water inlet valve 3 and the cooling water outlet valve 4 are continuously opened, and the whole working cavity is continuously cooled.
The present invention also includes such steps as an alarm step,
and when the fact that the water vapor in the working cavity exceeds a preset value is detected, controlling the frequency converter to output current to reduce the screw to a slow rotation speed, and giving an alarm.
It should be understood that although the present description refers to embodiments, not every embodiment contains only a single technical solution, and such description is for clarity only, and those skilled in the art should make the description as a whole, and the technical solutions in the embodiments can also be combined appropriately to form other embodiments understood by those skilled in the art.
The above-listed detailed description is only a specific description of a possible embodiment of the present invention, and they are not intended to limit the scope of the present invention, and equivalent embodiments or modifications made without departing from the technical spirit of the present invention should be included in the scope of the present invention.
Claims (10)
1. A control method of a dry screw vacuum pump is characterized in that: comprises the following steps of (a) carrying out,
self-checking, namely determining that all valves are in a closed state and ensuring that the pressure value in the pump is 0.8-0.9 atmospheric pressure;
starting, namely controlling a frequency converter to output current to a motor for controlling the rotation of the screws, enabling the two screws to simultaneously start to rotate slowly at the same speed for 2 minutes, and detecting a gap between the two screws;
heating, namely increasing the temperature in the pump through the electric conductor and keeping the temperature until the work of the vacuum pump is finished;
a standby step, maintaining the slow rotation speed of the screw and keeping the screw in an idle state;
starting, namely opening an air valve, controlling current to increase the rotating speed of the two screws to a target rotating speed, and starting to work; in the working process, nitrogen is introduced into the motor chamber through the nitrogen valve, so that the pressure value of the motor chamber is 1.2-1.5 atmospheres, the positive pressure is prevented from explosion, and the pressure of the motor chamber is ensured to be smaller than the pressure of the working chamber.
2. The method of controlling a dry screw vacuum pump according to claim 1, characterized in that: the gap between the two screws is detected by a rotary shaft angle encoder.
3. The method of controlling a dry screw vacuum pump according to claim 2, characterized in that: the slow turning speed is 500 rpm.
4. The method of controlling a dry screw vacuum pump according to claim 3, characterized in that: when the clearance between the two screws has deviation, the method also comprises a fine adjustment step, so that the rotating speeds of the two screws are ensured to be consistent.
5. The method of controlling a dry screw vacuum pump according to claim 1, characterized in that: the temperature in the pump was heated to 60 ℃.
6. The method of controlling a dry screw vacuum pump according to claim 1, characterized in that: the motor is a synchronous motor.
7. Method of controlling a dry screw vacuum pump according to any of claims 1-6, characterized in that: also comprises a step of cleaning the glass substrate,
after the vacuum pump works, introducing a cleaning solvent into the pump to clean the working cavity;
compressed air is introduced to blow dry the working cavity;
and introducing nitrogen into the working cavity through a nitrogen valve to replace the air in the cavity.
8. Method of controlling a dry screw vacuum pump according to any of claims 1-6, characterized in that: also comprises a cooling step, wherein the cooling step is carried out,
when the vacuum pump works, the cooling water inlet valve and the cooling water outlet valve are continuously opened, and the whole working cavity is continuously cooled.
9. Method of controlling a dry screw vacuum pump according to any of claims 1-6, characterized in that: also comprises a step of alarming, such as alarming,
and when the fact that the water vapor in the working cavity exceeds a preset value is detected, controlling the frequency converter to output current to reduce the screw to a slow rotation speed, and giving an alarm.
10. Method of controlling a dry screw vacuum pump according to any of claims 1-6, characterized in that: the nitrogen is replaced by other inert gases.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911170900.XA CN110939572B (en) | 2019-11-26 | 2019-11-26 | Control method of dry-type screw vacuum pump |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911170900.XA CN110939572B (en) | 2019-11-26 | 2019-11-26 | Control method of dry-type screw vacuum pump |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110939572A true CN110939572A (en) | 2020-03-31 |
| CN110939572B CN110939572B (en) | 2021-08-31 |
Family
ID=69908848
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911170900.XA Active CN110939572B (en) | 2019-11-26 | 2019-11-26 | Control method of dry-type screw vacuum pump |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110939572B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114593061A (en) * | 2022-03-07 | 2022-06-07 | 信尔胜机械（江苏）有限公司 | Screw vacuum pump's sealed inefficacy autoalarm |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012076373A2 (en) * | 2010-12-08 | 2012-06-14 | Eaton Aerospace Limited | On board inert gas generation system |
| CN106762651A (en) * | 2016-12-21 | 2017-05-31 | 江阴华西节能技术有限公司 | A kind of nitrogen-sealed dry screw vacuum pump |
| US20180051694A1 (en) * | 2016-08-18 | 2018-02-22 | Clemson University | Electro-mechanical controller for adjusting pump stroke on-the-go |
| CN109340116A (en) * | 2018-10-08 | 2019-02-15 | 江苏亚太工业泵科技发展有限公司 | Nitrogen-sealed screw vacuum pump built in exhaust side |
| CN109723643A (en) * | 2018-12-20 | 2019-05-07 | 江阴爱尔姆真空设备有限公司 | A kind of screw vacuum pump for clearing up dust |
-
2019
- 2019-11-26 CN CN201911170900.XA patent/CN110939572B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012076373A2 (en) * | 2010-12-08 | 2012-06-14 | Eaton Aerospace Limited | On board inert gas generation system |
| US20180051694A1 (en) * | 2016-08-18 | 2018-02-22 | Clemson University | Electro-mechanical controller for adjusting pump stroke on-the-go |
| CN106762651A (en) * | 2016-12-21 | 2017-05-31 | 江阴华西节能技术有限公司 | A kind of nitrogen-sealed dry screw vacuum pump |
| CN109340116A (en) * | 2018-10-08 | 2019-02-15 | 江苏亚太工业泵科技发展有限公司 | Nitrogen-sealed screw vacuum pump built in exhaust side |
| CN109723643A (en) * | 2018-12-20 | 2019-05-07 | 江阴爱尔姆真空设备有限公司 | A kind of screw vacuum pump for clearing up dust |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114593061A (en) * | 2022-03-07 | 2022-06-07 | 信尔胜机械（江苏）有限公司 | Screw vacuum pump's sealed inefficacy autoalarm |
| CN114593061B (en) * | 2022-03-07 | 2022-12-20 | 信尔胜机械（江苏）有限公司 | Screw vacuum pump's sealed inefficacy autoalarm |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110939572B (en) | 2021-08-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR940008174B1 (en) | Stage vacuum pump | |
| CN110939572B (en) | Control method of dry-type screw vacuum pump | |
| US5348448A (en) | Fluid rotating apparatus with plural drive motor synchronization system | |
| JPS62291479A (en) | Vacuum exhaust device | |
| JPH04275089A (en) | Multiaxle driver and hydraulic rotating unit | |
| JPH0267472A (en) | Pressure control method for vacuum equipment | |
| US20070172376A1 (en) | Vacuum pump | |
| CN2260228Y (en) | Apparatus for filling or recovering gas SF6 of oil-free type | |
| KR101641887B1 (en) | Dry Vacuum Pump having Screw Rotor and Groove | |
| JP5304934B2 (en) | Method for operating vacuum pump and method for manufacturing semiconductor device | |
| CN110879159A (en) | High-temperature high-humidity aerosol sampling device and sampling method | |
| US20080078503A1 (en) | Mechanical pump operating well for a long term and method of manufacturing the same | |
| CN113250931B (en) | Anti-dismantling structure based on air pressure detection and control method thereof | |
| CN102519246A (en) | Atmosphere-controllable high-speed rotary kiln | |
| JP3930297B2 (en) | Turbo molecular pump | |
| CN114318240B (en) | Method for coating film on inner wall of pipeline by poly-p-xylene | |
| JPS575592A (en) | Multivane compressor | |
| CN103594314B (en) | There is the vapor phase etchant equipment of Multicarity | |
| JP4107364B2 (en) | Vacuum equipment | |
| Burmistrov et al. | Development of scroll vacuum pump characteristics by thermal deformations compensation | |
| KR100992128B1 (en) | Treatment system for liquid crystal display | |
| CN220956039U (en) | Mechanical booster pump | |
| CN212426174U (en) | Sputtering coating vacuum pumping system | |
| CN216348673U (en) | Vacuum device for testing Q value of hemispherical harmonic oscillator | |
| CN220083547U (en) | Electric heating vacuum drying oven |
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 |