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The Ultimate Guide to Industrial Vacuum Pumps

Author: Site Editor     Publish Time: 2022-03-22      Origin: Site


What is an industrial vacuum pump?

Different Applications of an Industrial Vacuum Pumps

Industrial vacuum pumps are a certain mechanical device, which has been designed for extracting liquids or gases from the inside of any tubes, containers, or any other system where there is a need for reduced pressure to a certain level that can be less than the atmospheric pressure.

A reputed Chinese manufacturer of an industrial vacuum pump is Hangzhou Sunray Industrial Technology Co., Ltd. that can supply you with many different varieties of vacuum pumps for several industrial applications and uses. There are a variety of applications where such industrial vacuum pumps are used.

The following are a few of these industries where you can find applications of these vacuum pumps.

1. The food industry

The industrial vacuum pumps are extensively used in the food industries for the following applications:

  • Lyophilisation

  • Degassing

  • Drying

  • Concentration

  • Solvent separation

2. The electrical industry

A few common uses of these vacuum pumps are for drying and impregnation

  • Motors

  • Condensers

  • Coils

In addition to that, they are also used for degassing resins and varnishes.

3. The pharmaceutical industry

In various pharmaceutical industries these vacuum pumps are generally used for the following:

  • Degassing and drying

  • Freeze-drying and packaging

4. The toy industry

Metallization: In toy industries, vacuum can play an important role in which glass, plastic, or metal can be applied in the steam form.

5. The mechanical industry

Metallization: In various mechanical industries, the coating is applied by the coating metal, and then metal vapour will condense over the substrate.

6. The metallurgical industry

In metallurgical industries vacuum pump will be needed for the following operations:

  • Impregnation of castings

  • Sintering

  • Degassing

  • Thermal treatments

7. The optical industry

In various optical industries, the vacuum pump is used for depositing thin active layers.

8. The paper industry

In the paper industry, vacuum pumps are used for the following few processes:

  • Degassing

  • Drying

  • Metallisation

9. The plastic industry

In plastic industries, these vacuum pumps are used for the following few reasons:

  • Degassing and drying

  • Fusion, injection, moulding, and extrusion

  • Metallisation

10. The chemical industry

The following are a few operations in chemical industries, where vacuum pumps are needed:

  • Degassing and distilling

  • Desiccation and lyophilisation

  • Concentration and filtering

11. The textile industry

Drying and degassing: While manufacturing textiles, various dirt and dust can be produced which are eliminated through vacuum technology where vacuum pumps are needed.

12. The mining industry

These vacuum pumps are generally applied for vacuuming filtration, Exhaust gas recovery, Multi-effective evaporator, methane gas extraction, coal bed methane gas recovery, Mine natural gas boost, in the mining industry

13. The medical industry

The vacuum pump is needed for the central vacuum station during surgery and also sputum suction application etc.

14. The environmental industry

Vacuum pumps are needed in the environmental industry for:

  • Wastewater treatment

  • Biogas production

  • Digester gas compression,

  • Wastewater purification

  • Biogas recovery

15. The packaging industry

The vacuum pump is needed for applying vacuum during tea packing, vacuum packing, PET container productions, etc.

How does an industrial vacuum work?

Do You Know The Working Principles of Industrial Vacuum Pumps?

Do You Know The Working Principles of Industrial Vacuum Pumps?

You can find several applications of vacuum in industrial manufacturing processes that include packaging, pick and place, bottling, degassing, drying, to name a few. Now, let us try to understand the working or operating principle of these industrial vacuum pump briefly.

Working Principles of Industrial Vacuum Pumps

The basic task of vacuum pumps is to remove the air molecules as well as other gases out of the vacuum chamber. As the pressure within the chamber gets reduced during the flow, removal of any extra or unwanted molecules becomes very difficult.

Therefore, a certain industrial vacuum system must operate over certain portions in order to create a suitable environment for removal of unwanted molecules. The created vacuum can have an extraordinarily high-pressure range, which may typically vary between 1 - 10-6 Torr per 1.3 to 13.3 millibar of pressure.

However, in research and many other scientific applications, this can be further stretched to 10-9 Torr or even lower. For accomplishing this, different pump types can be used within a standard vacuum system, where each unit covers a proportion of the range of pressure, and they operate in series.

The pumps can be categorised as primary, secondary, or booster depending on the range of pressure they create. Primary pumps will have moderate pressure range, while the booster and secondary pumps will have high pressure range. The secondary pumps can even have ultra-high-range depending upon the application.

Gas Transfer Pumps

Here the pressure difference is created when the gas moves from the inlet of the pump to the outlet. The movement of the gas can be facilitated by positive displacement or by applying the kinetic pressure. There will be no difference in the gas molecules from either side but the pressure of the gas coming from the outlet will have pressure that is higher than the atmospheric pressure. The compression ratio is calculated by the difference in pressure from the inlet to the outlet.

Kinetic Transfer Pumps

In this type, fast moving blades are used to increase the momentum. It can also be done by sending the vapour to the gas to create momentum transfer. This type of pump is ideal for attaining low pressure and high compression. It is not typically used for sealed or closed systems.

Positive Displacement

These pumps have long shafts where a potion of gas is trapped and compressed at multiple stages to create positive displacement. High pressure is used to compress the mechanically trapped gas before being expelled to next pump or to the atmosphere. The flow rate can be adjusted in the series pumps

Entrapment Pumps

These pumps work on slow flow rate where the gasses are captured in the entrapment pumps. The pressure is increased in the capture pumps with help of ironic reaction or by condensation. Some pumps use chemical reaction to increase the pressure. This are oil-free systems since it does not have any moving parts.

These industrial vacuum pumps can be termed as wet or dry pumps depending of exposure of gas to water or oil particles during the process. Dry pumps work on oil-free environment while the wet pumps will need lubrication.

Types of Industrial Vacuum Pumps

Read To Know About Different Varieties of Industrial Vacuum Pumps

These days, dry pumps are very popular and used in place of oil-sealed rotary vane pumps and mostly used for many high and medium vacuum applications. Designers and also users of any vacuum furnaces will have a better understanding of the operation of such claw and screw types of pumps.

Dry screw pumps are used alone if a high vacuum will not be needed and a certain slower drawdown will be allowable when higher performance will be needed.

To obtain the highest performance of the system, both a secondary high-vacuum and a roots booster pump are utilized along with the primary pump that can provide the fastest speed for pumping and also the highest ultimate vacuum.

When they are used in series along with either any booster pump or along with both a secondary and booster high-vacuum pump, then the primary pump will be referred to as your “backing” pump.

Screw pumps generally belong to a certain dry compressing gas transfer pump family. They are considered as positive-displacement pumps that will use 2 screw-shaped inter-meshing rotors for moving gas along the axis of the screw.

You can find their applications as industrial vacuum pumps, often along with root blowers as an oil-free type of roughing pumps in certain high and also ultrahigh vacuum systems.

Principle of operation

Among the various technologies of vacuum pumps, screw pumps are generally considered as dry and positive displacement pumps. It is dry, as the gas that is transferred is not going to be exposed to water or oil used in a pump, whereas any wet pump will use water or oil as a lubricant to provide sealing.

Positive displacement may refer to the fact, the pump can work by mechanically trapping a certain volume of gas and then moving it through any dry vacuum pumps for creating a certain amount of low pressure on its inlet side.

Pros and cons of screw pumps


  • High robustness

  • Has got high tolerance against particles/dust and water vapour

  • Scales to as per customer requirements

  • It has very high speed for pumping

  • No contamination of its medium will be pumped

  • Rotation is frictionless - rotor wear can be eliminated

  • Because of internal compression, they are highly efficient

  • Costs of operation and maintenance needs are relatively low

  • Operation as frequency converter – can easily be optimised for the process that leads to higher energy efficiency


  • For pumping light gasses a certain gas ballast will be needed

  • For light gasses e.g. Helium and Hydrogen, ultimate pressure is the worse and lower speed for pumping if without any gas ballast

  • Not possible to scale down to certain smaller pumping speed less than 50 m³/h and below about 100 m³/h multistage roots.

Roots vacuum pumps

These vacuum pumps are also known as vacuum boosters. These pumps are dry vacuum pumps and are used along with backing pumps in many different applications where there is a need for any large pumping speed.

These vacuum boosters can operate totally contact-free and also without sealing fluids like water or oil in the chamber, although with a majority of models the 2 gearwheels of any synchromesh gearing and also the bearings for any impeller shafts will be lubricated with oil. A few roots vacuum or booster pumps are also equipped with a certain by-pass valve.

Operating principle of roots pump

You can call roots vacuum pumps as a rotary pump with positive-displacement variety where 2 impellers of symmetrical shape will rotate inside the casing of the pump past each other in very close proximity.

The 2 rotors have got a cross-section approximately resembling the figure ‘8’ shape and are suitably synchronized by a certain toothed gear.

The internal leakages of Roots pumps are mainly on the basis of the operating principle that certain pump chamber surface areas are assigned alternately to the pump’s input and the compression side.

During the compression phase, rotor and casing surface areas are loaded with gas during the suction phase, all gas is released. The traveling gas layer thickness will depend on the clearance existing between the 2 rotors and also between the casing wall and rotors.

The smallest clearances are attained at the operating pressures within 1 mbar range. Subsequently, it can be attained in this region with the highest compression ratios.

However, this pressure range also is most critical due to contacts existing between the casing and rotors.

Water ring vacuum pump

This vacuum pump having liquid ring is a rotating positive displacement machine for providing the necessary process vacuum in various industrial applications like electrical, chemical, environmental, food and beverage processing, mining and marine, oil and gas, pulp and paper, pharmaceutical, and textiles.

Water ring vacuum pump also utilizes water or any other processes that are compatible liquid as a sealant. Because of their simple operation, having no contact parts can make this vacuum pump having liquid ring a much safer and more reliable option for handling any dirty or dangerous gas streams.

Such liquid ring pumps are also available in both single and also dual-stage designs. They can also be configured as compressors to get more versatility.

Principle of Operation

The sealed liquid will form a ring inside any pump body while the impeller will spin to create small chambers meant for gas for trapping. The rotor axis is eccentric from its body and allows the liquid to fill, and then also empty each rotor chamber during the single revolution, forming the necessary gas compression for the pumping action.

The vacuum inlet and its atmospheric discharge ports will provide flow paths to the gas mixture.  The gas heat compression is dissipated into seal liquid, and a few amounts of liquid may flow out to discharge.

The discharge gas and remnant water discharge is set-apart from the stream of gas and directed to specific house exhaust, and then returned to the pump. Seal fluid is then replaced by a certain constant flow of any cooler seal fluid.  

Reliable liquid ring technology

A liquid ring pump's working concept revolves around a pump body and an eccentric rotor. The sealed liquid inside the pump forms a spinning "liquid ring" on the inner surface of the body as the rotor spins. Vacuum pump having liquid ring are available in three sizes:

  • Small capacity

  • Medium capacity

  • High capacity.

  • Small capacity pumps

Monoblock or lantern designs are used in small capacity vacuum pump having liquid ring. These designs have the advantages of a quick, small, and cost-effective installation. Small-capacity liquid ring pumps come in a variety of materials, including cast iron and stainless steel, and are suitable for a wide range of common industrial applications.

Medium capacity pumps

Medium capacity vacuum pump having liquid ring are high-capacity, the single-stage vacuum pump that can be used in a variety of industries, including oil and gas, general industrial, and chemical.

For less harsh applications, cast iron is available, and stainless steel is available for more hostile uses and conditions.

Large capacity pumps

Single-stage vacuum pumps with a capacity of the medium to large are excellent for demanding applications in harsh environments. These heavy-duty pumps can be used in a variety of applications, such as removal of water in a paper industry as well as vacuum filtering while processing mineral ore.

The big capacity pumps come in a range of materials, including stainless steel, cast iron, and poly-isoprene liner on some models.

2-Stage vacuum pumps with liquid ring

2-stage vacuum pumps with liquid ring are suitable for a wide range of industrial applications, and they can be paired with ejectors or boosters to create hybrid packages that achieve higher vacuum levels.

Two-stage water ring vacuum pump in ductile iron and stainless steel, as well as cast iron at two-stage vacuum pump having liquid ring.

Two-Stage water ring vacuum pump vs single stage vacuum pump

1. Single-stage Vacuum Pump having liquid ring

An impeller with multiple blades is placed in a cylindrical housing eccentrically and it is partly filled with sealing liquid to produce a vacuum in a single-vacuum pump having liquid ring.

The centrifugal force generated by the revolving impeller creates a liquid ring as the shaft rotates. The liquid ring is held against the inner wall of the pumping chamber by this force.

The depth of the blades at the entrance in the liquid ring drops and rises when the impeller rotates because it is off the centre in the plumbing chamber. On the inflow port side, this results in an increase in cell volume, which causes a vacuum.

As the blades advance into the liquid ring, the impeller cell volume decreases on the discharge port side. This raises the pressure until the discharge port is used to discharge the fluid.

2. Two-stage Vacuum Pump having liquid ring

An impeller with multiple blades is placed in a cylindrical housing eccentrically and it is partly filled with sealing liquid to produce a vacuum in a single-vacuum pump having liquid ring.

The centrifugal force generated by the revolving impeller creates a liquid ring as the shaft rotates. The liquid ring is held against the inner wall of the pumping chamber by this force.

The depth of the blades at the entrances drops and increases as the impeller rotates because it is off the centre in the plumbing chamber. This causes a vacuum on the inflow port side by raising cell volume.

As the blades advance in the liquid ring, the impeller cell volume decreases on the discharge port side. This raises the pressure until the discharge port is used to discharge the fluid. The sealing-liquid input provides a constant supply of new sealing liquid to the pump.

The discharge from the first stage of a two-stage liquid ring pump does not discharge to the atmosphere. Instead, the first stage empties through a discharge port in the intermediate plate between the first and second-stage impellers, as well as through the manifold leading to the second stage.

Water Ring Vacuum Pump Vs Dry Vacuum Pump

Often a critical decision will be faced in various process industry applications to select between any water ring vacuum pumps and dry screw pumps. Choosing the right vacuum pump can ensure efficient and smooth operation, maximize your return on investment and also improve reliability.

Let us, therefore, compare these two pumps based on the following four parameters:

1. Working principle

In a vacuum pump having liquid ring, vacuum generation will be done through a certain rotating multi-blade impeller. The impeller rotation creates a centrifugal force that forms a liquid ring and this creates the vacuum.

In dry screw vacuum pumps, vacuum is generated through the rotation of 2 screw rotors. No lubrication will be needed since there is no contact during the compression process.

2. Discharge temperature

The final temperature of discharge is controlled within 45°F to 150°F. Therefore, a vacuum pump having liquid ring can offer greater flexibility because different gases are either condensed or will pass through it.

The compression process in a dry vacuum pump is considered adiabatic, as with discharge temperatures are 450°F, which can cause safety concerns.

3. Operation conditions

Your vacuum pump having liquid ring may also be used for the dirtiest application and can work under harsh environments and violent saturated air. As the gas compression process will be isothermal, the pump can be used for pumping explosive, flammable, and toxic gases.

The dry screw vacuum pump may not be suitable for pumping any gases contaminated with dust, oil, or water vapour.

4. Maintenance cost

The only moving portion of a vacuum pump having liquid ring is the impeller, and there is no metal-to-metal contact between the spinning sections and the casing. Liquid ring pumps are easy to maintain due to these design features, and the accessories do not need to be replaced for 2-3 years.

Dry screw pumps necessitate lubricant replenishment and costly inlet filtration systems, which needs to be maintained on a regular basis. As a result, the total cost of dry screw pump repair and maintenance is considerable.

With all the above information, now you can decide your right pump for any of your industrial application. Selecting the right vacuum pump can ensure your smooth operation and also a high ROI (Return on Investments).

How to Choose the Right Industrial Vacuum Pump

How to Select the Right Kind of Industrial Vacuum Pump

You will find the applications of industrial vacuum pumps mainly in the Chemical industry, Electric Power, Pulp & Paper industry, Plastic industry, Mining, Pharmaceutical industry, Medical industry, Food & Beverage, Environmental industry, Metallurgical industry, Packaging industry, and Sugar industry, etc.

Industrial vacuum pump offers many benefits to the following industries by helping to do many different functions as has been detailed in the following as per the industries.

Right types of Industrial Vacuum Pumps for different industries

Let us look at the types of industrial vacuum pups that are used across various industries. Of course, there can be exceptions depending upon the specific nature of productions. Some industries might use non-conventional methods to create innovative results. However, it will give you a good indication about the kind of vacuum pumps to look for according to the industry type.

Electric Power Sector - Commonly used pumps in this sector are water ring vacuum pump, rotary vacuum pump, and roots vacuum blower.

  1. Chemical industry - Roots vacuum blower and water ring vacuum pump, and Rotary vacuum pump.

  2. Pulp & Paper industry - The most commonly used pump in this industry is liquid ring vacuum pump.

  3. Mining industry - roots vacuum pump blower, liquid ring vacuum pump, dry scroll vacuum pump, and rotary piston vacuum pump.

  4. Pharmaceutical sector - Roots Vacuum pump blower, Liquid ring vacuum pump, dry scroll vacuum pump, Rotary Piston Vacuum Pump, steam ejector vacuum pump.

  5. Plastic manufacturing industry - In most cases, Liquid ring vacuum pump is used in the plastic manufacturing sector.

  6. Medical sector - central vacuum system and liquid ring vacuum pump, are most commonly used in the medical manufacturing sector.

  7. Environmental sector manufacturing - roots vacuum pump blower, liquid ring vacuum pump, dry scroll vacuum pump, rotary piston vacuum pump, rotary vane pump and steam ejector vacuum pump,

  8. Food & Beverage manufacturing sector - roots vacuum pump blower, liquid ring vacuum pump, dry scroll vacuum pump, rotary piston vacuum pump, rotary vane pump and steam ejector vacuum pump.

  9. Packaging industry - rotary vane vacuum pump and liquid ring vacuum pump.

  10. Sugar industry - The most commonly used vacuum pump in Sugar industry is liquid ring vacuum pump.

Few tips to select the right vacuum pump

To find and select the right vacuum pump will need a good understanding of your need and application in the respective industry. Besides, what level of vacuum will be needed must be very well known. You also need a complete understanding of the process where you are going to make use of this vacuum pump.

The following are the few things that should be known to you for making a proper selection of your vacuum pump.

1. Vacuum level

Your pump selection will depend heavily on what vacuum level you need for your application. Typically, the following are the different levels of vacuum:

Rough vacuum

Medium vacuum

High vacuum

Ultra-high vacuum

Extreme high vacuum

2. How pump will impact the process

When the vacuum pump will run then it will offer a certain amount of vacuum pressure but along with that, it can also produce vibration and noise. It is, therefore, necessary to evaluate how that can impact your process.

3. Maintenance needs

Depending upon the application, you may either have to run the vacuum pump continuously or intermittently as per the need of your process. Hence there will be wear and tear too. So, you need to evaluate the maintenance needs too.

You must also know what spare parts and consumables are needed to run the pump efficiently.

4. Various options available

There are many different varieties of pumps available and based on your application, you must select the type of pump that suits you the best for your application.  

5. Operating condition

You must also make sure the operating conditions like the temperature of the environment where the vacuum pump will work are suitable for the pump by looking at its specification.

6. Utility requirements

You must also know the electrical supply, space, and any other facility requirements of the pump during its installation and operation and whether that can be arranged on your site.

7. Physical dimension

You must know the physical dimension of the pump whether it can be suitably accommodated within the space available at the site for proper operation. There must be sufficient space available for its ventilation as the temperature of the pump will rise if it has to run continuously.  

8. Cost of the pump

Last but not the least; you need to see the cost of the pump so that it can fit within your budget.

Choosing China manufacturer for your industrial vacuum pump

Any China industrial vacuum pump manufacturer can offer quality vacuum pumps at very competitive prices and you can find several manufacturers available in China manufacturing such vacuum pumps of many different specifications.

You can Google, Bing, or make a Yahoo search. You can come across a few online sourcing platforms like:

  • Alibaba

  • Global Sources

  • Made in China

Finding any Chinese industrial vacuum pump manufacturer will be easy to find on these sites. Chinese suppliers will offer the following warranty conditions:


The industrial vacuum pump manufacturer in China will offer a warranty for 18 months after the shipping or 12 months after the complete installation and testing at the site of the customer, whichever date will come first (Warranty for easy-wearing parts are not included)

After sale-services:

  1. The manufacturer will respond if you ask any questions within 24 hours.

  2. After delivering, the supplier will track your shipping and update the status, until you receive the products.

  3. The manufacturer will arrange their engineer for helping installation and testing at the site of the customer, or communicate to the customer for guiding the installation and solve your problem at the site (if any) via phone, e-mail, video, WhatsApp, or WeChat etc. until all products work well.

  4. The manufacturer will provide the customer the most cost-effective price for any spare parts needed in the future.

Hope you make an informed vacuum pump choice for your industry!