The vacuum pump can be divided into many different models and variations. They are mainly used in the business sector, but many private activities would be unthinkable without them. Although there are many variations of a vacuum pump, all devices are based on one of two basic principles, which we will explain later in this article.
With our big vacuum pump test 2021 we want to help you find the perfect device for you. We have looked at the most important private vacuum pump applications and summarised them for you. We also show you the advantages and disadvantages of each type of vacuum pump.
- 1 Weekly newsletter with the best personal finance tips
- 2 Summary
- 3 The Best Vacuum Pump: Our Picks
- 4 Buying and evaluation criteria for vacuum pumps
- 5 Guide: Questions you should ask yourself before buying a vacuum pump
- 5.1 How does a vacuum pump work?
- 5.2 What is special about a vacuum pump and what advantages does it offer?
- 5.3 What types of vacuum pumps are there?
- 5.4 For whom are vacuum pumps suitable?
- 5.5 What does a vacuum pump cost?
- 5.6 What are the alternatives to a vacuum pump?
- 5.7 What is the difference between an oil-free and a lubricated vacuum pump?
- 6 Conclusion
- Due to their wide product variety, vacuum pumps can be used in many different operational as well as private fields of activity.
- There are several types of vacuum pumps. These include, for example, rotary vane, diaphragm and turbomolecular vacuum pumps.
- In order to make the best purchase decision, you should find out which type of vacuum is required for your specific work. But also the chemical compatibility, performance and maintenance should be considered.
The Best Vacuum Pump: Our Picks
Buying and evaluation criteria for vacuum pumps
To help you make the right choice, we have summarised the most important criteria below. Since there are many different applications for a vacuum pump, you should consider in advance exactly in which context you want to use the pump.
In the following, we will list the general evaluation criteria that you should inform yourself about before buying.
In summary, these are:
- Quality of the vacuum level
- Chemical compatibility
- Pump flow rate and performance
- Maintenance and operation
In the further sections we go into more detail on these criteria.
Quality of the vacuum level
What matters here is the number of molecules obtained, which is measured by the pressure of the residual gases. The weaker the pressure, the lower the number of molecules per square centimetre.
Basically, there are three different types of vacuum that can be generated depending on the vacuum pump. These differ primarily in the molecular density and, derivatively, in the maximum pressure of the device:
The primary vacuum is the weakest vacuum, as it has the most residual molecules and can therefore only generate a maximum pressure of 1 millibar.
Especially with a vacuum pump with secondary vacuum there are serious differences in the maximum pressure, this can vary between 3- 10 millibar. A vacuum pump with ultravacuum can generate the highest maximum pressure of up to 17 millibar.
The more maximum pressure that can be generated, the lower the minimum pressure!
Depending on the application, a different pressure and thus a different vacuum type is needed. You should therefore find out before buying which pressure specifications have to be achieved for your project.
This purchase criterion is particularly important in the field of refrigeration technology, i.e. for mobile vehicles or air conditioning systems. Different refrigerants are used here, which must be compatible with the respective vacuum pump.
New refrigerants in particular are sometimes flammable and therefore require special pump systems. These vacuum pumps are usually somewhat more expensive than the previous models, but have a longer service life and are also compatible with older refrigerants.
This purchase criterion is not only essential in refrigeration, but can be transferred to many other areas of application. If a vacuum pump is operated in combination with chemical liquids, you should find out before buying whether the pump is also designed for the respective liquids.
Pump flow rate and performance
The various performance values are made up of a number of different influencing factors and specifications of the vacuum pump:
In the field of cooling and air conditioning, the primary performance, how many litres per minute of refrigerant the vacuum pump can transport, is decisive. This performance value is determined by the maximum pressure and the pump throughput.
The pump throughput depends on the emptying time of the machine. The higher the throughput, the more litres per minute the machine can process.
Before buying your vacuum pump, find out about the most important performance values in your area of application. This will help you to compare the different machines and make an optimal purchase decision.
Maintenance and operation
Depending on the vacuum type and vacuum variation, the pump requires different maintenance. These extra costs should be taken into account when buying, as the maintenance cycles can differ greatly from device to device.
You should definitely maintain the vacuum pump properly, otherwise the lifetime of the device will be reduced and you will have to buy a new pump sooner. These purchase costs are of course even higher than the investment you would need for maintenance.
Before buying your vacuum pump, you should therefore consider how efficiently you want your device to work and how much time you want to spend on the maintenance of your vacuum pump.
Guide: Questions you should ask yourself before buying a vacuum pump
In the following section, we have summarised the most frequently asked questions about "vacuum pumps" for you. On the one hand, general information is given, and on the other hand, specific questions about use are answered.
How does a vacuum pump work?
Furthermore, a vacuum pump is based on one of two basic principles:
- Gas binding vacuum pump: This is based on the principle of sorption, where particles are bound to a solid surface. This process reduces the pressure in the receiver. Typical gas-binding vacuum pumps are, for example, adsorption pumps or cryogenic pumps.
- Gas transfer vacuum pump: This pump system transports particles in a closed working chamber or by means of impulse transfer (e.g. by shocks). Typical gas transfer vacuum pumps are, for example, diaphragm pumps or turbomolecular pumps.
Later in this article, we will present the respective types, with their advantages and disadvantages, in more detail.
What is special about a vacuum pump and what advantages does it offer?
- Plant and mechanical engineering
The advantage of a vacuum pump is above all the large negative pressure it can generate. Thus, for example, the device is able to transport several hundred litres of liquid in a few minutes. It also works more efficiently and usually more quietly than its competitors.
What types of vacuum pumps are there?
- Rotary vane vacuum pump
- Diaphragm vacuum pump
- Liquid ring vacuum pump
- Scroll vacuum pump
- Turbomolecular vacuum pump
We will now give you basic information about the respective models with their advantages and disadvantages.
Rotary vane vacuum pump
Rotary vane vacuum pumps are small, compact and usually have a low price. Furthermore, they generate a primary vacuum and are suitable for liquids with a high boiling point.
To ensure high efficiency and durability of the unit, most models are lubricated with oil. Therefore, such models are less "clean" and require more regular maintenance.
This type of vacuum pump is mainly used in the industrial and food sectors.
Diaphragm vacuum pump
Diaphragm vacuum pumps are characterised by their high resistance to corrosion and chemicals. These models are mainly used for continuous operations.
Furthermore, they do not require lubricants and are therefore easier to maintain than pallet vacuum pumps. However, this advantage is reflected in the more expensive purchase costs. It should also be noted that they only have a low pump throughput (maximum 20 m3/h) and a low vacuum level.
This type of vacuum pump is mainly used in the food and cosmetics industries.
Liquid ring vacuum pump
A liquid ring vacuum pump has a high resistance to a wide range of substances and is ideal for explosive or heat-sensitive products.
Furthermore, these models have a high pump flow rate of up to 30000 m3/h and can therefore be used for a wide range of activities. High cleanliness of the unit is ensured by not using lubricants.
This type of vacuum pump is used in distilleries, sugar factories, power stations and mines.
Scroll vacuum pump
Scroll vacuum pumps are small, compact and quiet. Due to their efficient pump flow of up to 30000 m3/h, these models are mostly used for pumping liquids.
In addition, no oil or such lubricants are required, which ensures a high level of cleanliness of the unit. However, the seals on these models are very sensitive and therefore need to be changed and maintained more often.
This type of vacuum pump is mainly used in research and laboratory facilities.
Turbomolecular vacuum pump
Turbomolecular vacuum pumps have a very high maximum pressure (10-12 millibar) and efficient pumping rates (50-5000 litres per second). They are based on the principle of an electric motor and are operated by a motor.
Due to the high maximum pressure, these models can generate an ultra-vacuum, whereby a primary pump is always required for operation. No oil is used for the application, which has a positive effect on the cleanliness of the device. However, it should be noted that such models have high purchase and maintenance costs.
This type of vacuum pump is mainly used in industry and research.
For whom are vacuum pumps suitable?
When buying, you should bear in mind that vacuum pumps are usually a bit more expensive than conventional devices and require more maintenance. However, if you are willing to invest a little more money and time, you will acquire one of the best alternatives on the market.
We therefore recommend buying a vacuum pump whenever there is a vacuum pump solution from established manufacturers for the job(s) in question.
What does a vacuum pump cost?
|Area of application||Price|
|Air-conditioning units||120 - 200€|
|Car brake release||20 - 60€|
|Hand-held vacuum pump||20 - 30€|
However, large-scale vacuum pumps are usually only used in the business sector, but they are significantly more expensive than the devices used in the private sector.
Vacuum pump prices in the business sector can only be estimated approximately, as each manufacturer offers different conditions to different customers.
We would now like to give you a brief overview of the prices of the types of vacuum pumps mentioned above:
|Rotary vane vacuum pump||180 - 3000€|
|Diaphragm vacuum pump||700 - 7000€|
|Liquid ring vacuum pump||1500 - no limit|
|Scroll vacuum pump||3000€ - no limit|
|Turbomolecular vacuum pump||2000€ - no limit|
Overall, the two sectors cannot be compared with each other. The price range is mainly determined by size, performance, pump throughput, equipment and the quality of the workmanship.
What are the alternatives to a vacuum pump?
In some areas, there are occasionally cheaper alternatives, which we would now like to show you:
|Field of application||alternative|
|Garden (care)||drill pump|
|Storage and sealing||electric pump|
|Waste water treatment||rotary piston blower|
|Water treatment||screw blower|
|Chemical process engineering||gas-cooled Roots pump|
With the exception of the drill pump, which can be used universally in private households, the other alternatives are very specialised and are usually only used in companies. Small vacuum pumps used in the household for vacuuming food can also be replaced by other electric pumps.
What is the difference between an oil-free and a lubricated vacuum pump?
|Type of vacuum pump||strengths||weaknesses|
|Lubricated vacuum pump||work more efficiently and are more robust against effects such as humidity or heat||need to be maintained very often and cannot be used in the food, pharmaceutical or medical industry due to the oil lubricant|
|Dry vacuum pump||Require less maintenance and can be used in sterile work areas due to their low risk of contamination||Are less efficient and more susceptible to moisture and heat|
Due to their different characteristics, the two types of vacuum pumps are used very specifically for a particular field of activity.
Due to their sophisticated system, vacuum pumps have revolutionised the pumping system. They offer high speed, performance and resistance and are therefore used in a wide range of applications, from food packaging to medicine.
Due to constant development, vacuum pumps are being used more and more in new markets. But even in established sectors, work without the pumping system is no longer imaginable.
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