Selection of lining materials for corrosion resistant vacuum pump

Corrosion resistant vacuum pump is a kind of self-priming pump with liquid corrosion resistance and long service life. Its material must be special. The first characteristic is corrosion resistance. Next, we introduce the selection of lining materials for corrosion-resistant pump 

It is necessary to satisfy the technical parameters of flow, head, pressure, temperature, NPSH and other technical parameters of corrosion-resistant vacuum pump products. It is necessary to satisfy the requirements of medium characteristics. F46, as the material of equipment fabric, absorbs a few touch substances in the process of application because there is a small space between F4 macromolecules, which is dispersed and relocated among them. The absorption image is usually shown by a small amount of weight gain and color change, and the amount of absorption increases with the increase of working pressure and touch time. In addition, it can be solved by lowering the temperature, shaking the scale and improving the planning.

In addition, the volume of pores between macromolecules increases with the increase of temperature, and liquid absorption and infiltration will also be added. Thus, the circulation effect at high temperature will cause the liquid absorbed by F4 to expand or transpiration, resulting in pores, and finally form damage. For example, after 34 months of operation, small spots appear on the surface of the pipeline of trichlorosilane rectification equipment, which will be carried out continuously in small shifts for one year. Therefore, this is the demand for F4 sheet as chemical anti-corrosion fabric. The lower the porosity content, the better. The specific gravity is necessary to be greater than 2.18, and the thickness is also required, usually 1.5 ~ 3 mm. The planned service life of the pump is usually at least 10 years. When determining the type and manufacturer of the pump, we should sum up and consider the pump's function, energy consumption, reliability, quotation and manufacturing standards.

Water Ring Vacuum Pump

Dry Scroll Vacuum Pump

industrial vacuum pumps,vacuum furnaces

Effect of pressure on corrosion resistant vacuum pump

The use of corrosion-resistant vacuum pump is under the action of a certain pressure, for the pressure formed by different altitudes, the impact of vacuum pump is different. The use of corrosion-resistant water ring vacuum pump skillfully uses this principle. 

Corrosion resistant vacuum pump is used to pump the gas in the system, and then discharge to the surrounding atmosphere to form a vacuum, or pump the surrounding atmosphere to discharge into the system to form pressure. Obviously, the ambient atmospheric pressure has an important influence on the performance of corrosion-resistant water ring vacuum pump. The design of corrosion-resistant water ring vacuum pump is based on the assumption that the ambient pressure is a standard atmospheric pressure. All its performances refer to the performance under this condition. Due to the requirements of process flow, the inlet or outlet pressure of corrosion-resistant water ring vacuum pump is sometimes not equal to one atmospheric pressure even if it is operated at sea level around one standard atmospheric pressure. For example, the inlet of some corrosion-resistant water ring vacuum pump requires the vacuum of the system, while the outlet requires compressed gas, that is to say, it is required to be used as a vacuum pump and a compressor at the same time. It is also possible to master the changes of pump performance according to the law of the influence of atmospheric pressure on pump performance.

If we have mastered the law of the influence of different atmospheric pressure caused by altitude on pump performance, we can design corrosion-resistant water ring vacuum pump suitable for each altitude area according to this law, and we can also convert the operation of corrosion-resistant water ring vacuum pump under non-standard atmospheric pressure conditions (such as in different altitude areas) according to this law In this way, the corrosion-resistant water ring vacuum pump meeting the requirements can be correctly selected.

CL Sereis Cone Liquid Ring Vacuum Pump

Roots Blowers

Roots Vacuum Pump 

Wear reason of glass fiber reinforced plastic water ring vacuum pump

The wear of glass fiber reinforced plastic water ring vacuum pump is essential, so what is the cause of its wear? Let's analyze the wear factors of glass fiber reinforced plastic water ring vacuum pump together 

The wear of the journal surface of glass fiber reinforced plastic water ring vacuum pump is uneven. The radial wear of the main journal and the connecting rod journal is mainly elliptical, and the maximum wear parts are corresponding to each other, that is, the maximum wear place of each main journal is close to the side of the connecting rod journal, and the maximum wear place of the connecting rod journal is also close to the side of the main journal. The crankshaft journal also has conical wear along the axial direction. The elliptical wear of journal is caused by the uneven distribution of the force acting on the journal along the circumference

When the engine is working, the comprehensive force acting on the connecting rod journal always acts on the inner side of the connecting rod journal, and the direction is outward along the radius of the crankshaft, resulting in the maximum wear on the inner side of the connecting rod journal and forming an ellipse. The reason for the conical wear of the connecting rod journal is that the oil passage leading to the connecting rod journal is inclined. When the glass fiber reinforced plastic water ring vacuum pump rotates, the mechanical impurities in the lubricating oil accumulate on one side of the connecting rod journal under the action of centrifugal force, which accelerates the wear of the side journal and makes the wear of the connecting rod journal cone-shaped.

In addition, the bending of the connecting rod, the cylinder center line is not vertical to the center line of the glass fiber reinforced plastic water ring vacuum pump, etc., will make the axial force of the journal uneven, resulting in wear deflection. The wear of the main journal is elliptical, which is mainly due to the influence of centrifugal force of connecting rod, connecting rod journal and crank arm, which makes the relative wear between the side close to the connecting rod journal and the bearing larger. In addition, abrasions and burns may occur on the surface of the journal. Scuffing is mainly due to the oil is not clean, which large hard mechanical impurities in the journal surface scratch caused. The burn on the surface of journal is caused by Bush burning, which is mainly caused by insufficient lubrication, too thin oil and blocked oil circuit.

API 681 Liquid Ring Systems

Rotary Vane Vacuum Pump

Dry Scroll Vacuum Pump

Regular maintenance of vacuum pump unit

With the rapid development of the national economy, enterprises and units put forward higher and higher requirements for the safe and reliable operation of vacuum pump units. In order to achieve this requirement, we must do a good job in the regular preventive maintenance of vacuum pump unit. 

1. According to the scheduled time interval to the site for machine repair.

2. Repair or replace the equipment before major failure occurs. If properly arranged, the maintenance cost of this scheme will be less than that of post accident maintenance.

3. When the vacuum pump unit does not need to work continuously, it is obvious that the technical personnel with rich maintenance experience can carry out regular preventive maintenance.

4. Otherwise, it will cause unnecessary maintenance. There will also be a series of problems, such as the complete machine being disassembled, repeated secondary installation leading to the decline of installation accuracy and so on.

Regular preventive maintenance of vacuum pump unit is the key to its work efficiency. It can make the vacuum pump unit in a stable working state for a long time, reduce energy consumption and prolong its service life.

Water Ring Vacuum Pump

Dry Scroll Vacuum Pump

industrial vacuum pumps,vacuum furnaces

2BV water ring vacuum pump pressure

For 2BV water ring vacuum pump knowledge, I believe you have a certain understanding, to have a better use of it, you need to know about its pressure knowledge, the following is about its pressure knowledge. 

1. Limit absolute pressure: the absolute pressure is how much higher the measured internal pressure is than the "theoretical vacuum (theoretical vacuum pressure value is 0Pa)". It compares the absolute vacuum pressure of the theoretical state. Due to the limitation of technology, we can't pump the internal pressure to the absolute vacuum value of 0Pa in any case. Therefore, the vacuum value pumped by 2BV water ring vacuum pump is higher than the theoretical vacuum value. So when expressed in absolute vacuum, there is no negative sign in front of the value.

2. Limit relative pressure: the relative pressure is how much lower the measured internal pressure is than the "atmospheric pressure". It shows that the actual value of system pressure is lower than that of atmospheric pressure. Because the air inside the container is pumped, the pressure inside the 2BV water ring vacuum pump is always lower than the external pressure of the container. Therefore, when expressed in terms of relative pressure or gauge pressure, the value must be preceded by a negative sign, indicating that the internal pressure of the container is lower than the external pressure.

CL Sereis Cone Liquid Ring Vacuum Pump

Roots Blowers

Roots Vacuum Pump 

Causes of inner wall wear of rotary vane vacuum pump

Any kind of mechanical products will wear after working for a long time. Let's discuss the causes of wear and how to reduce the wear. 

Rotary vane vacuum pump uses vacuum oil as sealing medium. Besides sealing, oil also lubricates. The deterioration of oil results in performance degradation, which easily aggravates the wear of pump wall. If the extracted gas contains water vapor, which enters into the pump cavity, the vacuum oil will be emulsified and the performance of the oil will be reduced. There is also a case that the exhaust volume is large, and it is easy to wear the inner wall. How to understand? Vacuum pump is the equipment to obtain vacuum. If the vacuum can not be obtained for a long time, the load of the pump will be large and it is easy to wear.

The phenomenon of inner wall wear is common in chemical industry. How to solve it? We can choose other more suitable models to replace, which not only ensures your benefits, but also saves you costs.

Vacuum Pump Or Compressor

Water ring vacuum pump

Rotary Vane Vacuum Pump

Vacuum pipeline system of water jet vacuum pump

Water jet vacuum pump consists of nozzle, suction chamber, mixing pipe and diffuser (commonly known as tail pipe). The centrifugal pump is used to increase the water pressure, so that the water with a certain pressure is ejected from the nozzle with high speed jet. At this time, the energy of water changes from pressure to kinetic energy, and the surface pressure of the jet decreases rapidly. Due to the viscous and entraining effect of the high-speed jet on the surrounding gas, the air is continuously sucked in. High velocity moving water column and air flow form foam flow to the diffuser (tail tube) at the mixing pipe, and as the section enlarges, the flow velocity decreases and the pressure rises in the diffuser until the atmospheric pressure is higher than the atmospheric pressure and discharged into the atmosphere. It can be seen that if the tail pipe is too short, the vacuum pumping capacity of the water ejector will be reduced, and if the operation is not careful, it may also cause water backflow. 

In view of the problems existing in the vacuum system, we have taken the following measures for rectification:

1) The pipeline not conforming to the design in the vacuum system was completely replaced. The diameter of outlet pipe of centrifugal pump was changed from 70mm to 80mm, and the diameter of vacuum main pipe was changed from 50mm to 65mm;

2) The installation height of the water jet vacuum pump is raised by 1.4m as a whole, and a 1.2m long tail pipe is installed at the ejector outlet.

After the rectification of the vacuum system, the vacuum pump has played its due role, and the vacuum degree of the vacuum system has reached the design requirements. This rectification work puts forward higher requirements for technical personnel: when working, they should not rely on experience to work. They should first understand the structural principle of the equipment, be good at grasping the key points and breakthrough points of things, and avoid detours. This can be used for reference in future work.

Water Ring Vacuum Pump

Dry Scroll Vacuum Pump

industrial vacuum pumps,vacuum furnaces

Market prospect of oil free scroll vacuum pump

Oil free scroll vacuum pump has the characteristics of oil-free, clean, low vibration noise and low energy consumption, so it has broad development prospects and market potential. However, due to the complex design and manufacturing technology of the scroll pump, mass production has not been realized in China at present, which can not meet the increasing market demand, so it can only rely on imported products with high price and inconvenient after-sales service. In addition, affected by many factors such as the development of the market and the degree of understanding of users, the vortex pump has not formed a virtuous cycle in China. 

Even so, the actual annual demand of scroll pumps in China is still more than thousands. It can be considered that with the emergence of high-precision CNC machine tools and machining centers, opportunities have been brought for the development of vortex technology, and the key manufacturing technology has been broken through; At the same time, China now has a certain number of experienced professionals in design, research and development, testing, analysis and use, and are committed to the technical development of pumps. It is believed that in the near future, domestic oil-free scroll vacuum pumps with moderate price, reliable performance and batch production will become the mainstream products suitable for the requirements of China's market. Therefore, increasing investment, R & D and mass production of scroll vacuum pump suitable for domestic demand has become one of the important tasks of the whole vacuum acquisition industry in China.

CL Sereis Cone Liquid Ring Vacuum Pump

Roots Blowers

Roots Vacuum Pump

Failure caused by corrosion of centrifugal pump and water ring vacuum pump

Centrifugal pump and water ring vacuum pump are the power components of spraying truck. Under the joint action of centrifugal pump and water ring vacuum pump, liquid is pumped from liquid source or charging bucket and transported to the charging bucket or outside. Therefore, centrifugal pump and water ring vacuum pump are the parts that contact water or detergent most. Meanwhile, the rotating speed of centrifugal pump is up to 2000r / min, Under the combined influence of the scouring action of the washing fluid with particles and the cavitation of the fluid, it is easy to produce corrosion and various faults. 

For example, due to corrosion between the pump cover and the pump body, it is easy to leak liquid or the fixed nut is rusty, which is not easy to disassemble and install. The corrosion of the inner wall of the pump body and the impeller of the centrifugal pump affects the rotation of the impeller, or the temperature is too high due to friction, and the noise of the centrifugal pump is too high; the pump shaft is corroded under the action of the detergent, and the strength is reduced, resulting in the loose fixation of the impeller; the inner wall of the pump body and the impeller of the water ring vacuum pump are loose At the same time, corrosion affects the rotation of the impeller, or the temperature is too high due to friction, and the phenomenon of excessive noise of centrifugal pump; the leakage of liquid and air at the connection part of inlet pipe and exhaust pipe between centrifugal pump and water ring pump affects the filling of water.

Liquid Ring Systems

Rotary Vane Vacuum Pump

Dry Scroll Vacuum Pump 

The reason of vacuum failure of water ring vacuum pump

As one of the common equipment of dehydration parts in paper mill, water ring vacuum pump can be used for suction water tank and vacuum roller to draw water in the paper. The working principle is: before starting the water ring pump, water ring is formed at the rim by rotating the cylindrical impeller after the start-up. Because the cavity shell of the pump body is oval, the water ring rotating with the impeller wheel will be pushed in and out in the impeller chamber, resulting in vacuum and pressure transmission. 

After two or three years of use, the vacuum suction capacity of water ring vacuum pump will be decreased. There are also some problems in the vacuum suction capacity of many 2BV water ring vacuum pumps used in a paper mill. Later, the whole vacuum pump was disassembled and inspected, and the reason for its failure was finally found.

1. many cavitation pits of different sizes and shapes are formed on the blades of impeller, which are more serious in the rim part, and the largest cavitation pit can reach 60 × 15 × 30mm3.

2. the tolerance of the matching between the elliptical cavity shell and impeller of the pump body becomes larger.

Water Ring Vacuum Pump

Dry Scroll Vacuum Pump

industrial vacuum pumps,vacuum furnaces 

Reciprocating vacuum pump

 Reciprocating vacuum pump is a double acting vacuum pump made in the former Soviet Union. It is composed of piston, air valve, cylinder, crosshead, connecting rod, crank and other parts. The bearing bush and cylinder of vacuum pump are supplied by special lubrication system. The lubricating oil brands are large and the consumption is large. Due to the high heat generated by gas compression, the room temperature is still as high as 40 ℃ in summer, even though it is equipped with cylinder cooling system, which is unfavorable to the equipment and the body. Moreover, the maintenance of the equipment is inconvenient, the failures are frequent, the maintenance period of cylinder cleaning and pad grinding is long, and the consumption of spare parts is large. 

2be water ring vacuum pump is a single-stage and single action vacuum pump produced by referring to foreign advanced technology. It is an energy-saving product. 2be water ring vacuum pump adopts axial suction and exhaust structure, mainly composed of pump body, impeller, main shaft, drive side distributor, non drive side distributor side cover, automatic drain valve and other parts. The impeller is eccentrically installed in the pump body. When the impeller rotates, the pump body is affected by centrifugal force and forms a rotating liquid ring on the inner wall of the pump. The gap between the impeller end face and the adapter is sealed by liquid. During the rotation process of the impeller at the first half rotation (passing through the suction hole), the volume of the sealed cavity gradually expands, and the gas is inhaled from the suction hole, and then rotates in the latter half rotation (passing through the exhaust hole) In the process, the sealing volume gradually reduces, and the gas is discharged from the exhaust hole to complete a gas extraction process.

CL Sereis Cone Liquid Ring Vacuum Pump

Roots Blowers

Roots Vacuum Pump

Influence of pipeline on the performance of rotary vane vacuum pump

For users, the diameter of the suction pipe should be the same as the diameter of the pump port, and the length should be as short as possible. Too many elbows and too long pipeline will not only affect the pumping speed, but also affect the power consumption. Exhaust pipe is also the same, exhaust pipe is the most easily ignored by users, too long pipe will increase exhaust resistance, increase gas backflow, affect pumping speed, and increase power consumption. 

The oil mist eliminator of rotary vane vacuum pump developed by us, which is connected to the exhaust port of the pump, can meet the requirements of gas indoor emission. Of course, the oil mist eliminator will inevitably lose part of the power. After careful design and repeated improvement, not only the exhaust resistance is small, but also the effect is very good, and the increase of power is not obvious. It should be noted that the core of the oil mist eliminator must be replaced regularly according to the use condition.

Vacuum Pump For Negative Pressure Evaporation

Rotary Vane Vacuum Pump

Dry Scroll Vacuum Pump

Maintenance of 2XZ rotary vane vacuum pump

The maintenance of 2XZ rotary vane vacuum pump is the key to maintain the safe and long-term operation of 2XZ rotary vane vacuum pump 

1. Keep the 2XZ rotary vane vacuum pump clean to prevent foreign matters from entering the pump;

2. Keep the oil level and do not run without oil;

3. Pay attention to observe the cleanness of the oil. If the pump oil becomes dirty, turbid, enters water or other volatile substances and affects the limit vacuum, the pump oil should be replaced in time. To replace the new oil, first start the pump and run for 30 minutes to make the pump oil thinner. Stop the pump and drain the oil from the oil drain hole. Then, open the air inlet to run for 1-2 minutes. During this time, a small amount of clean pump oil can be added from the air inlet to replace the oil in the pump cavity. After confirming that the pump has been cleaned several times, install the oil drain plug, and then inject clean pump oil from the oil filling hole to the oil level line;

4. When it is not used for a long time, it should be covered with suction and exhaust caps and placed in a dry place, and attention should be paid to moisture and rust prevention;

5. If it needs to be disassembled and overhauled, it must be carried out by professionals who have certain experience in repairing the pump, or contact the manufacturer.

Water Ring Vacuum Pump

Dry Scroll Vacuum Pump

industrial vacuum pumps,vacuum furnaces 

Tightness of vacuum pump system

The tightness of the vacuum pump system is extremely important for the user's use process. Some users will call to say that the vacuum degree can not meet the requirements after receiving the water ring vacuum pump of our company. After the professional guidance of our company's technical personnel, excluding other reasons, it is found that the leakage of the user's pipeline causes the vacuum degree not to go up. How much does the leakage rate bring to the performance of the vacuum pump system The impact of! 

In practical application, when it is found that there is air leakage in vacuum pump, it is necessary to distinguish whether there is air leakage in vacuum degree or pipeline, because the solutions adopted by the two are different

1) Methods to check whether there is air leakage in the vacuum pump: directly measure the air inlet of the vacuum pump with a vacuum meter to see how much vacuum degree can be reached if the pump is tested by single measurement. If it reaches the specified standard, the possibility of air leakage of the vacuum pump is ruled out;

2) Check whether there is air leakage in the pipeline: the most commonly used method is to test whether there is air leakage in the pipeline or remove a section of the pipeline, connect one end to the pump without air leakage, and measure the other end with a vacuum gauge. Through this method, the air leakage point can be identified.

CL Sereis Cone Liquid Ring Vacuum Pump

Roots Blowers

Roots Vacuum Pump

Impeller machining of water ring vacuum pump

Impeller is an important part of water ring vacuum pump, which plays an important role. From blank processing to mechanical processing, every step of this component should meet the requirements of size, quality and material. Only in this way can we achieve stable operation. The processing of impeller should be standardized, and each step of processing should be accurate, and small links should not be ignored Only in this way can the quality of the whole vacuum pump be improved. 

The blank casting of impeller is directly related to the machining step. The reliable quality of the blank can ensure that there will be no defects such as fracture and deformation during machining. The components of water ring vacuum pump have accurate design requirements, and the size of impeller is strictly measured. Therefore, the requirements of design drawings should be strictly followed from casting to machined parts Each processing link should be accurate to avoid production waste.

Whether the impeller production of water ring vacuum pump conforms to the design standard is inspected and passed by the quality inspection department. If only the wheel fails to meet the standard, problems will occur during assembly, which will easily lead to the overall failure of the pump. Standardized and standard unified examination should be conducted for the impeller processing. No matter in which link, the operator should be responsible and play a good technical ability, Strengthen their sense of responsibility and do the work in place.

Vacuum System Of Tissue Paper Machine

Rotary Vane Vacuum Pump

Dry Scroll Vacuum Pump

Eccentric machining method for eccentric parts of rotary vane vacuum pump

Rotary vane vacuum pump and slide valve vacuum pump belong to oil seal mechanical vacuum pump. In structure, there is an off center position relative to the pump cavity. This position is the central position for installing the rotating parts. Its relative size often affects the assembly and vacuum performance of vacuum pump. Either the rotating parts cannot be installed or the inner wall of the pump chamber cannot be contacted well after being installed No sealing and poor vacuum performance. 

Therefore, whether in production or repair, we should pay attention to the eccentric processing problem, and strictly control the eccentric size. For 2x series rotary vane vacuum pump, the eccentricity is on the middle diaphragm, and the bearing supporting the rotor is installed on the eccentricity. The position of the bearing affects the assembly clearance of the rotor. Therefore, if it is not done well, the vacuum degree is often unstable, or the outer circle dimension tolerance of the rotor must be modified to make up for it. This is good for maintaining a small number of pumps, but not for mass production.

If you want the dimensional accuracy to be stable, it depends on the tooling. Among the various errors in the processing process, the selection of positioning reference is the most important.

Water Ring Vacuum Pump

Dry Scroll Vacuum Pump

industrial vacuum pumps,vacuum furnaces

Technical knowledge of water ring vacuum pump

 First of all, we should understand the working range of vacuum pump and water ring, but we should pay more attention to the application of water ring and water ring? 

Water ring vacuum pump can also be simply called water ring pump. It is a kind of rotary variable volume vacuum pump which can change the volume. It is mainly composed of impeller, pump body, suction and exhaust disc, suction port, exhaust port, auxiliary exhaust valve and other parts. When working, it mainly rotates at high speed through the eccentric rotor with fixed blades inside, throwing the medium into the pump body through the suction process to the stator The liquid ring, which is concentric with the stator, is formed by external force. The liquid ring and the high-speed rotating fixed blade constitute a kind of variable volume vacuum pump with variable volume.

The working principle of water ring vacuum pump is to fill the pump first, that is to avoid the rotor idling and inject appropriate amount of water. When the pump starts according to the start-up procedure, with the high-speed rotation of the fixed blade, the filled water also runs at high speed due to external force, resulting in centrifugal effect, and forms a water ring in the outer ring of the fixed blade. When the fixed blade is rotated to be connected with the suction port and the exhaust port, the suction process and exhaust process are carried out respectively. During the suction process, the volume of the small chamber gradually increases from small to large. During the exhaust process, due to the continuous rotation of the impeller, the gas is compressed, and the gas is discharged when connected with the exhaust port.

CL Sereis Cone Liquid Ring Vacuum Pump

Roots Blowers

Roots Vacuum Pump 

Development of Roots vacuum pump unit

Facing the current application of Roots vacuum pump unit, from the perspective of all talents, its useful role shows the excellent function of the equipment. As the application of the unit, the power promotion in all aspects of production has a great effect. From the talent advantage of the product to the development of the function, the utilization rate of the product is greatly promoted. For the future development of the unit, we should improve all functions according to different needs, and increase the application function of the whole set of equipment, so as to improve the overall level of the unit. 

For the use of Roots vacuum pump unit, according to the needs of practice to improve the whole, in the function and utilization rate of the unit for leading scientific rectification, add its advantage of the process to promote, adjust the use of products in all aspects of the function, with a strong value to improve its use, for the future production and application of the root function development, to have The use of talent to expand the functional progress of products.

With the enhancement of market competition, there is a higher demand for Roots vacuum pump unit. If we can show the advantages of the whole product, increase the application investment of product utilization rate and provide efficient service for the user's production process, it will be useful to recognize all specifications and increase the advantages of various functions of products.

Vacuum Pump In Crystalline Silicon Solar Cells

Rotary Vane Vacuum Pump

Dry Scroll Vacuum Pump

Composition of medical negative pressure system

Medical negative pressure suction system is composed of user pipe network and vacuum suction station. The user pipe network includes combination terminal and hanging tower; the vacuum suction station includes electric control cabinet, water ring vacuum pump, medical vacuum tank, sterilization filter, gas-liquid separator, sewage collection tank, etc. By vacuumizing the vacuum tank, the vacuum tank can maintain a certain negative pressure, and continuously provide suction to the user pipe network to meet the needs of users. 

The working process of medical negative pressure system: gas end point → sewage collection tank → vacuum tank → sterilizer → vacuum pump → gas water separator → waste gas evacuation, sewage liquid is collected in a centralized way and sent to sewage treatment station.

Water Ring Vacuum Pump

Dry Scroll Vacuum Pump

industrial vacuum pumps,vacuum furnaces 

Dust removal and filtration method of oil seal vacuum pump

Some vacuum processes will produce a lot of dust. If the dust enters the oil seal vacuum pump with the extracted gas, it will accelerate the wear of the parts in the pump cavity like abrasive, cause wear and damage to the pump rotor and pump cavity, block the oil circuit or make the pump unable to run. If the dust enters the vacuum valve, it will make the seal invalid and leak, so the dust prevention and filtering has been completed The use of dust filters in vacuum systems must be critical for increasing the lifetime of the dust system. 

When the amount of dust is small, it can be filtered by the pump oil filtering system, but when the dust amount is large, the dust collector must be used to prevent the damage of the vacuum pump and ensure the normal operation of the vacuum pump.

CL Sereis Cone Liquid Ring Vacuum Pump

Roots Blowers

Roots Vacuum Pump

Oil vacuum pump system

From the perspective of energy saving and emission reduction, it is a problem that every vacuum operator must face up to. The traditional concept of oil-free is only to obtain a clean, carbon free hydride pollution-free vacuum environment. Today's "oil-free" not only meets the requirements of clean vacuum environment, but also protects the environment to prevent the pollution and emission of waste oil and waste gas.

The traditional oil vacuum system (2x type rotary vane vacuum pump) generally has low energy utilization rate, especially the oil booster pump and oil diffusion pump. It is under this background that the molecular pump is widely used and has the potential to replace the traditional diffusion pump in the area less than 400 mm. The power of the diffusion pump is five times higher than that of the molecular pump with the same diameter of 250mm. In the long run, the market space of oil vacuum system is bound to be narrower and narrower.

Function Of Various Vacuum Pumps In Vacuum System

Rotary Vane Vacuum Pump

Dry Scroll Vacuum Pump

Screw vacuum pump product market

Because the screw vacuum pump only needs a pair of screws, and there is a certain gap between the screw and the screw, so when the screw vacuum pump is working, the noise is very low, the speed is uniform, the most important thing is that there is no need for lubricating oil during the operation, so the dry screw vacuum pump can operate in the environment with a lot of water vapor, which is a very energy-saving vacuum product. 

Now in the market with the continuous screw vacuum pump products, the general vacuum pump can not be satisfied with the oil-free condition, so the dry screw vacuum pump competition in the market is growing, so the screw vacuum pump has replaced many vacuum pump products, many oil vacuum pump has been replaced by oil-free vacuum pump, now many companies have replaced screw vacuum pump 。

Therefore, the market of screw vacuum pump is getting better and better, so the prospect of screw vacuum pump is naturally very good. The future development trend of screw vacuum pump is environmental protection: with the increasingly serious pollution problem in recent years, the topic of environmental protection has been mentioned again and again, so the production and production of various products in the future should pay more attention to environmental protection.

What problems do vacuum pump need to deal with to achieve the purpose of environmental protection and energy conservation and emission reduction? The answer is noise reduction. The development of new materials and new skills will promote the reduction of oscillation and noise. We will work together to deal with the problem of oil injection and oil leakage of pumps, so as to achieve the purpose of cleaning the environment. We will carry out personalized and refined development: we will satisfy the increasingly diversified needs of different categories.

Water Ring Vacuum Pump

Dry Scroll Vacuum Pump

industrial vacuum pumps,vacuum furnaces

Difference between roots vacuum pump and roots blower

The operating principle of Roots vacuum pump and roots blower are the same, both belong to positive displacement blower, and the structure of the whole machine is basically the same, but there are still some differences in some accessories. Roots blower belongs to blower blowing system and belongs to positive pressure fan class, while roots vacuum pump belongs to negative pressure suction system and belongs to negative pressure fan class. What else exists between them What about the difference? Let's have a look at it.

What is the difference between roots vacuum pump and roots blower? Because roots vacuum pump is suction, it needs to customer service atmospheric pressure, so it is more difficult to overcome negative pressure, and positive pressure blower can rely on atmospheric pressure, positive pressure rise can be stronger, pressure scale is more extensive.

Since the production of Roots vacuum pump is more difficult, the price of general roots vacuum pump will be higher than that of Roots blower. We can look at the quotation of the same type. The price of vacuum pump is often higher. After roots blower is installed, it can be used. However, roots vacuum pump may need to be equipped with front stage pump when starting.

The purpose of the front stage pump is to ensure that the roots vacuum pump will not rise to a very high negative pressure. Therefore, the front stage pump is required to increase the negative pressure first, and then open the roots vacuum pump to continuously increase the pressure. In terms of operation principle, roots blower can sweep clean and pollution-free gas without daily smoothness. And its speed is fast, each part of the open space is small, less emission.

CL Sereis Cone Liquid Ring Vacuum Pump

Roots Blowers

Roots Vacuum Pump 

Water ring vacuum pump has strong corrosion resistance

Compared with the most common SK series water ring vacuum pump, water ring vacuum pump has the characteristics of strong corrosion resistance, high limit vacuum degree and large exhaust volume. It is widely used in food, petroleum, chemical industry, metallurgy and other professional fields, and can also pump various gases and corrosive gases without solid particles. 

There are two main shock absorption methods: the transmission system is reformed. In order to reduce the vibration intention of the motor and transmission shaft, SK water ring vacuum pump is used to transfer the rigid connection with the transmission shaft into elastic connection. The elastic sleeve pin coupling is used to adjust the maximum compensation displacement and compensation angle, so that the vibration of the motor and drive shaft can be compensated through the elastic coupling and will not be directly transmitted to sk water ring vacuum pump.

Considering that it is difficult to reinforce SK water ring vacuum pump, the method of welding "reinforcing rib" in the outlet steel pipe is adopted. Along the inlet and outlet direction, the flange at both ends of the connecting steel pipe between the outlet pipe of SK water ring vacuum pump and the outlet valve can be consulted by the seller for welding with several steel plates of specified thickness and width. The stiffness of steel pipe is added to reduce deformation and resist displacement.


Roots Blower Can Transport Gas

Rotary Vane Vacuum Pump

Dry Scroll Vacuum Pump

Power supply configuration of claw vacuum pump

Claw type vacuum pump, claw type air pump, claw type water pump, etc., after connecting the power supply, the power supply voltage should be stable under any load and working condition. With switching power supply is a better solution. If the power supply is not regulated, the voltage may be very high when the pump is not connected. Once the pump is connected, the power supply voltage will drop sharply. Even if the voltage after connecting the pump is equal to the rated working voltage. At this time, the power supply voltage will fluctuate abnormally, leading to the pump's work will be completely disordered. 

It is also not advisable to divide and depressurize by resistance, because the working current of pump will change when the load of gas (water) circuit changes, which will lead to the change of resistance voltage. Therefore, the power supply must have voltage stabilizing function. In actual purchase, with and without voltage stabilizing function, the price difference is very small, it is recommended to buy with voltage stabilizing function.

The output current that the power supply can provide must be larger than the working current of the pump, so as to ensure the energy demand of the pump. And choose power supply, must not choose the price is too cheap switching power supply. In order to attract customers to buy this kind of power supply, the parameters usually have false mark and false report.

Vacuum Impregnation Technology

Rotary Vane Vacuum Pump

Dry Scroll Vacuum Pump

High precision roots vacuum pump

 It is one of the effective anti-corrosion measures to apply organic coating on the surface of composite materials. Surface adhesive coating protection can be widely used in the repair and pre protection coating of abrasion and cavitation corrosion parts. It has good chemical resistance, excellent mechanical properties and adhesive properties. Compared with the traditional welding repair of pressure vessel, it has the characteristics of simple construction, low cost, safety performance and good repair effect. Repair step surface treatment thoroughly surface oxide layer, clean the surface with 

Noise, ultra-low vibration, can work under high temperature conditions (about 100 degrees), without cooling and other characteristics, which have been verified and recognized by the majority of users. Because of its unique product shape, excellent manufacturing technology, customer-oriented service concept has been recognized by customers. The working principle and performance characteristics of roots pump are essentially the same as cam pump, but the rotor is roots type. It can transport liquids with viscosity of tens of thousands of centipoises. Roots pump is mainly has two opposite rotation direction

CL Sereis Cone Liquid Ring Vacuum Pump

Roots Blowers

Roots Vacuum Pump 

Market competitiveness of water ring vacuum pump

In the development process of continuously developing the practical performance of its products, competitiveness has become a driving force for the overall quality development of the equipment. On the basis of enhancing the application ability of various aspects of its advantages, the overall application strength of the product has been accelerated. 

In order to improve the performance of water ring vacuum pump application performance, in order to achieve the advantages of the development of its products in all aspects, fully reflect its practical performance in all aspects, and constantly drive its overall excellence with practical product strength The improvement of potential ability can reflect the application performance of the equipment in the actual effect of various aspects of application, so as to give full play to the practical effect of the product under the overall application ability according to the drive of quality strength.

Market competitiveness is also a kind of promotion for the development of water ring vacuum pump. In the practical process of vigorously developing its overall application, it is necessary to increase the performance of the overall value of the product with a reliable advantage level, and further develop the overall development of its practical advantages combined with the play of its comprehensive performance, so as to reflect the performance of the overall performance of the product with the strength of all aspects.

Water Ring Vacuum Pump

Dry Scroll Vacuum Pump

industrial vacuum pumps,vacuum furnaces

Positive displacement vacuum pump

Claw vacuum pump is not only a kind of positive displacement vacuum pump, but also a dry vacuum pump. 

Claw vacuum pump, like roots vacuum pump and screw vacuum pump, is a non-contact dry vacuum pump. In general, in order to achieve a certain compression ratio, rotational speed and dynamic balance, claw vacuum pump is usually composed of multi-stage claw rotor in series or roots rotor and multi-stage claw rotor in series. At present, three-stage claw rotor and one-stage roots rotor are commonly used, or four-stage claw rotor is connected in series. The performance of roots plus claw type is generally better than that of claw type vacuum pump.

In multi-stage claw vacuum pump, according to the form of rotor, phase difference and diaphragm, it can be divided into spiral type, anti claw type and spiral anti claw type, and their performance is also different.

For claw type vacuum energy, the higher the rotating speed, the greater the compression ratio. In general, the speed of claw vacuum pump is 3000r / min, and the limit pressure is 1-10pa.

CL Sereis Cone Liquid Ring Vacuum Pump

Roots Blowers

Roots Vacuum Pump 

Configuration of high vacuum unit

Different vacuum systems require different degrees of vacuum. Therefore, it is often necessary to complete by a set of vacuum units, that is, the vacuum pumps working in different pressure ranges are connected in series.

The vacuum pump with high vacuum discharge can meet the requirements of vacuum pump on one side. Obviously, the simplest vacuum unit is a vacuum pump with direct discharge to the atmosphere. However, the high vacuum system generally needs three-stage units, and the medium vacuum system generally needs two-stage units.

It is difficult for a high vacuum pump and a low vacuum pump to form an effective high vacuum unit. There are several reasons for this. The continuity of traffic is one of them. High vacuum pump has the limitation of pressure resistance of the front stage, that is, if the former stage is higher than a certain pressure, the pump can not work normally. When the current stage pump reaches this critical pressure, the pumping speed will be reduced, so the exhaust flow of the front stage pump may be less than that of the main pump. The inconsistency of the flow rate destroys the requirement of flow continuity, which will inevitably cause the vacuum unit not to work normally. However, if a medium vacuum pump is connected between the high and low vacuum pumps, it can serve as a connecting link between the preceding and the following. The flow rate is continuous, and all pumps can work in the best state. Roots pump can work in the medium vacuum range, is the most suitable, so it is also known as roots booster pump, because its compression ratio is not high, just can connect a few PA to hundreds of PA range. When the three-stage high vacuum unit enters a higher vacuum degree, due to the obvious reduction of the exhaust flow of the main pump, the continuity of air extraction can be maintained only by a small front stage pump. In practical application, this method is often used, which can reduce the energy consumption of the unit.

Another reason why high vacuum units often need three-stage units is due to the limitation of suction pressure of high vacuum pump. All pumps have initial working pressure, and traditional high vacuum pumps are in the range of several PA. Therefore, the front stage pump must be pre pumped to this pressure before the main pump can start to work. However, it usually takes a long time for the front-stage pump to pump to this pressure, because the pumping speed of the pump decreases with the decrease of the pressure. Especially for the vacuum unit with periodic air pumping, the time required for reaching the working vacuum degree is required. The longer the pre pumping time is, the longer the time for entering the working vacuum degree is. Therefore, a medium vacuum pump is added to cooperate with the front stage low vacuum pump to realize the working vacuum degree It takes a short time to reach the working pressure of the main pump, so that the system can enter into the working pressure as soon as possible, thus ensuring the use efficiency of the equipment.

Rotary Vacuum Pump For Photoresist Removal

Water ring vacuum pump

Rotary Vane Vacuum Pump

closed cycle vacuum pump working principle

For most people, the closed cycle vacuum pump is undoubtedly an unknown number. Well, let's not talk about how it works. Maybe a lot of people don't even know what it does. Let's introduce the working principle of closed cycle vacuum pump so that we can fully understand it. 

The closed circulating vacuum pump is composed of roots pump, which is connected in series with the front pump. The water ring pump selected for closed cycle vacuum unit is more advantageous than other vacuum pumps because it not only overcomes the limit pressure difference limit when using single water ring pump (the unit limit pressure is much higher than the limit pressure). Under a certain pressure, the water ring pump has low pumping rate and retains its shortcomings. Roots pump works quickly and has the advantages of high pumping rate. Especially when the vacuum pump can not discharge condensed steam, or the solvent used will make the pump oil worse and affect the performance, or when the vacuum system does not allow oil polling, it is more obvious. Dilute. If equipped with explosion-proof motors and electrical appliances, and comply with the corresponding safety regulations, they can also remove flammable and explosive gases.

Therefore, the closed cycle vacuum pump can be widely used in vacuum distillation, vacuum evaporation and crystallization in chemical industry, freeze-drying in food industry, vacuum drying in pharmaceutical industry, polyester chip in light textile industry.

Water Ring Vacuum Pump

Dry Scroll Vacuum Pump

industrial vacuum pumps,vacuum furnaces

Quality of Roots vacuum pump

The practical production of Roots vacuum pump is carried out through various processes. In order to strengthen the quality of the blank, the deep processing should be carried out strictly. The management system should be done in time to help the production of waste products. Under the condition of not affecting the order production, the waste parts should be treated well, and the man hour quota should be controlled well On the basis of the bottom operation, we should timely corresponding to the needs of the market, and strengthen the optimization of the processing technology of the products. 

The use of Roots vacuum pump strength has become an important condition to promote the development of enterprise productivity. Its use in different occupations has different application ability, but the same point is that it can not be used as a single pump, it can only be assembled with other equipment into unit products for use, playing a driving strength foundation. Through the use function of the equipment itself, it can be useful For the use of other equipment to achieve a higher functional strength, improve the driving effect of product application.

Under the premise of accelerating the development of Roots vacuum pump's useful effect, it is necessary to make continuous performance of product application and function, further enhance the improvement of its product superiority, let the application of its products drive the development of enterprise's productivity, promote the continuous improvement of its application function in all aspects, fully accelerate the driving of its product application ability, and make it continuously perform on the basis of rational use Show the outstanding performance of the product application effect, and then show the usable function of the equipment.

In order to improve the quality of Roots vacuum pump, it is necessary to combine the status of product application, improve the development of all application strength, and constantly complete the overall driving of product application ability, so that it can enhance the continuous improvement of its quality advantage under the advantage effect of reasonable use, and make it show internal use advantage in the development process.

CL Sereis Cone Liquid Ring Vacuum Pump

Roots Blowers

Roots Vacuum Pump

Roots rotary vane vacuum pump unit operation

The first very important process of using roots rotary vane vacuum pump unit is the preparation before starting. Check all parts, check whether the cooling circuit of roots pump is smooth, and check the exhaust valve to ensure that it is in the open state. Pay attention to check to ensure that the oil level of each pump is on the oil level line. If it is below the oil level line, it is required to add oil. If it exceeds the oil level line, it should be drained. Check whether the rotation direction of the motor is the same as that of the arrow on the pump. If the use of equipment is suspended for a long time, are the parts rolling sensitive when starting up again? If it can't roll, it is necessary to roll several revolutions by manpower. It is absolutely forbidden to start it by force with the motor, which will cause serious damage to the pump. 

The second process is to pay attention to the problems when starting. Before starting, the cooling water valve of roots pump should be opened, and the front stage pump of rotary vane vacuum pump should be started to open the inlet valve of front stage pump together. Open the air inlet valve of the front and rear stage, and turn on the air valve smoothly. During the working process of the equipment, if the temperature of some parts is too high, there may be irregular noise, or other abnormal phenomena. The roots rotary vacuum unit should stop checking immediately.

The third operation is to stop the problem that the device needs to pay attention to. Before stopping, the inlet valve should be closed first, and the vent valve of roots pump should be opened. Then the equipment will stop actively. Close the inlet valve of the front stage pump and stop the front stage pump together. The valve of the cooling water device is closed. If the operation is stopped for a long time, the roots rotor vacuum unit should drain all the water in the cooling water jacket in the cold zone, otherwise, the water in the sleeve will swell and cause damage due to freezing.

Finally, repair and maintenance, roots rotary vacuum unit should adhere to the environment around the equipment clean and boring. Always check the smoothness of each part. If there is a lack of smooth oil, it should be made up in time. When the lubricating oil is polluted, clean lubricating oil should be replaced in time. After replacement, the bolts should be tightened from the beginning to ensure the sealing environment. When disassembling and repairing, all parts must not be struck by external force. Pay special attention to the smooth and smooth sealing surface, otherwise it will cause air leakage after re installation.

H Piston Vacumm Pump Start And Stop

Rotary Vane Vacuum Pump

Dry Scroll Vacuum Pump

Influence of cooling system temperature on the performance of vacuum pump unit

 In summer, the temperature of closed water can reach 35 ℃. Therefore, it is difficult to guarantee the supercooling degree of 4.2 ℃ in the actual operation of vacuum pump. As the sealing water temperature approaches to saturation, its pumping capacity also decreases, until saturated vaporization and loss of working capacity. 

The working pressure of the vacuum pump and the pressure of the condenser is a dynamic balance process. No matter how high or low the circulating water temperature is, the suction pressure of the vacuum pump must be lower than that of the condenser in order to pump the non condensable gas from the condenser. Therefore, the sealing water temperature of vacuum pump must be lower than the saturation temperature corresponding to the exhaust pressure.

For example, the vacuum of No.3 unit of a company was reduced because the water in the gas water separator was not changed in time, which led to the vaporization of sealing water in the vacuum pump. A few days later, the test was carried out on vacuum pump a of No.2 unit. After adding 16 ℃ cold water into pump a, the temperature of separator was 16.2 ℃. After starting pump a, the temperature rose to 24.5 ℃. With the increase of temperature, the vacuum decreased. When the water temperature was 30 ℃, the vacuum increased about 1kPa and the current of vacuum pump increased about 0.85a. When the working water temperature drops by 1 ℃, the vacuum increases by about 0.19kpa. It can be seen from the test that it is an important means to ensure the vacuum of the vacuum unit to ensure the lower temperature of the sealing water of the vacuum pump in summer.

Water Ring Vacuum Pump

Dry Scroll Vacuum Pump

industrial vacuum pumps,vacuum furnaces

Maintenance of fixed plate mechanical vacuum pump

The structure of fixed plate mechanical vacuum pump is all combined, similar to small five pieces. The exhaust valve is of the bullet type. If it is used for a long time, the bullet will also fly off, resulting in the failure of no air extraction; some pumps have manufacturing problems, the vent hole is too oblique, the bullet can not return to its original position after being lifted by the air flow, and the valve port can not be blocked, so the vacuum degree is not high. When repairing, the air outlet can be reamed into the inlay sleeve to correct the air outlet, so as to overcome the above problems. 

After several years of service, the vacuum degree of the fixed plate vacuum pump becomes worse due to wear and tear. At this time, the pieces can be disassembled and grinded against each other. After being cleaned, they can be assembled. At this time, if the tolerance between the rotor and the end face is too small, some end faces can be ground and installed again. The stator is tightened by the spring to keep it close to the rotor forever to prevent the reverse "breakthrough" of gas. Therefore, the spring has a large expansion frequency and is easy to break. If one of the two springs is broken, the pulsating sound of the exhaust valve is paroxysmal, and the fuel tank cap can be disassembled for inspection.

In winter, the viscosity of the oil sometimes becomes very large, after stopping the pump, the air is not put into the pump cavity in time, causing the oil to fill the pump cavity. When the pump is started suddenly, the oil in the cavity is difficult to be squeezed out at once. The stator is often squeezed out of the stator groove or the rotor is broken (or even the rotor is cracked), so it is impossible to pump air. When repairing, only the fixed piece is out of the way. The end of the fixed piece can be gently knocked with a wooden strip to make it return to its original position, and the belt pulley is turned on manually. After the pump oil in the cavity is discharged, the pump can be started for air extraction. If the rotor is damaged, it should be replaced with a new one. Therefore, the fixed vane pump start and normal use must comply with certain regulations, should also stipulate the oil change system on schedule.


CL Sereis Cone Liquid Ring Vacuum Pump

Roots Blowers

Roots Vacuum Pump 

Limit pressure of rotary vane vacuum pump

Soon after the rotary vane vacuum pump began to work, the minimum pressure P'g appeared. The pump continued to run, because of the increase of pump temperature, the saturated vapor pressure of pump oil increased, the viscosity decreased, and the inlet pressure slightly increased to PG. PG is the minimum stable pressure obtained by the pump and also the ultimate pressure of the pump. 

The limit pressure of rotary vane vacuum pump is related to the type of vacuum gauge used in measurement. The results show that the limit pressure is about one order of magnitude lower than that measured by a heat conduction vacuum gauge (thermocouple or piezometer, etc.). This is because the former can only measure the partial pressure of the permanent gas, and the latter can measure the total pressure of the compressed gas. The current regulation of our country is to measure the limit pressure of mechanical pump with oil seal by using compression vacuum gauge.

The amount of circulating oil also affects the limit pressure of the pump. With the increase of oil quantity, the sealing effect is better. The relationship between the limit pressure and oil quantity of rotary vane vacuum pump changes, and the saturated vapor pressure Po of oil is finally reached. In fact, the pump oil contains a lot of air and water. After the pump oil enters the pump cavity, the air and water absorbed in the pump oil are released again. The relationship between the pump limit pressure and the oil quantity develops upward. Generally, the pump oil should be kept at the specified oil level to keep the circulating oil volume of the pump constant. For the two-stage pump, the pump oil can enter the high vacuum stage only after degassing in the low vacuum stage, which can reduce the amount of bleeding of the pump oil in the high vacuum stage and reduce the limit pressure of the pump.

Water Ring Vacuum Pump Repair Knowledge

Rotary Vane Vacuum Pump

Dry Scroll Vacuum Pump

Vacuum pump treatment of pollution in vacuum system

 Low vacuum devices such as vacuum transportation, vacuum impregnation, vacuum filtration, vacuum monotony, vacuum degassing (liquid steel disposal) are required to have low vacuum pump units with high working pressure and large displacement. The main pumps of such low vacuum pumping units are reciprocating vacuum pump, oil sealed vacuum pump, steam radiation pump, water ring pump, roots pump, etc. 

According to the cleaning degree, humidity or other special requirements, the low vacuum pumping unit should be equipped with necessary dust remover, monotone tank and other components. During the tightening process, water vapor will condense into water droplets and mix with the pump to form a suspension, which will not only make the vacuum drop, but also rust the pump cavity and rotor, destroy the sealing surface and make the limit vacuum of the pump drop. Therefore, it is very important to prevent water vapor from polluting the mechanical pump.

Water Ring Vacuum Pump

Dry Scroll Vacuum Pump

industrial vacuum pumps,vacuum furnaces

Front stage vacuum pump in vacuum application

The pump which can provide the necessary pre stage pressure for other pumps which can not directly exhaust to the atmosphere is called the front stage pump. Among them, some pumps can work in two ways, sometimes discharged into the atmosphere, and sometimes discharged into the pre pressure of decompression. 

All types of pumps can exhaust air to the atmosphere, but their effective working area depends on their working principle. If the sealing fluid is not used, the high compression ratio cannot be maintained, and the mechanical clearance cannot be made small enough to effectively prevent the secondary expansion or backflow. Pumps without sealing fluid are suitable for working near atmospheric pressure. Because it is difficult to dissipate the heat of compression, some dry mechanical pumps, especially roots pump and thousand screw compressor, are limited in their low pressure and strong operation. These pumps should work above 30otorr. If materials such as carbon, graphitized cast iron and high temperature synthetic materials are used, the working area of dry vane pump can be extended to 150 Torr due to the self-lubricating property of these materials. In the same pressure area, liquid ring pump, reciprocating piston pump and lower efficiency jet pump can be effectively used. If double-stage liquid ring pump, valveless multi-slice pump, double-stage reciprocating piston pump, liquid jet pump and double-stage steam jet pump are used, the pressure area can even be extended to about 30 Torr. When the working pressure is further reduced, the relatively simple pump may no longer be applicable, and the multi-stage rotary oil seal pump must be used, and the sealing fluid with low steam pressure must be selected. 

The effective working pressure of single-stage pump is mainly due to the influence of oil pollution, so it is limited to 0.l Torr. Due to the same influence, the low pressure working limit of the two-stage oil seal pump is slightly lower than 10mtorr. The oil vapor pressure arc of about 1mtorr makes roots pump with two-stage oil seal pump (at effective pumping speed) unable to work in 10-6 Torr area. It is more effective to use other pumping equipment, such as diffusion pump, ion pump, etc., for pumping air below 1mtorr. As far as mechanical pumping is concerned, turbomolecular pumps are best used in this area.

CL Sereis Cone Liquid Ring Vacuum Pump

Roots Blowers

Roots Vacuum Pump