Thursday, November 16

Vacuum Pumps 101

Vacuum pumps are a large facet of Zorn Compressor’s business and are found in many manufacturing facilities. Vacuum pumps are very similar to air compressors, except for the way they operate is essentially the inverse of an air compressor!  Read the below post to learn about the basics of vacuum pumps and their applications.

What is Vacuum?

Let’s get technical for a second…

Industrial vacuum pumps are made to provide a steady supply of vacuum the same way your home vacuum is supposed to provide continued suction to pick up debris on your floor. These industrial pumps are used on a much larger, industrial scale to perform various manufacturing functions or provide clean environments. These vacuum pumps are air pumps that work with a specified inlet pressure that is below the atmospheric pressure. They are designed to bring down the atmospheric pressure, otherwise known as the pressure around the machine, and bring it to the desired process demand level. In doing so, they are essentially removing air or gas molecules from the space between two different areas- one with higher gas density and one with lower gas density. When this gas is removed, it forces the surrounding pressures to hold these two areas together in a somewhat suction-like effect.

So, vacuum pumps remove air molecules and other gases from the inside of a vacuum chamber, changing the pressure of the chamber and making it difficult to entirely remove all molecules within the chamber. Thus, the vacuum, suction-like, effect.

But to make it simpler…

Vacuum pumps pull large volumes of air into the vacuum chamber. When the air is pulled in, the area left where the air once existed creates a vacuum effect.

Types & Technologies

Wet Industrial Vacuum Pumps

Wet vacuum pumps are positive-displacement pumps that utilize oil or water for lubrication and sealing. These are a common choice in industrial manufacturing as they are long-lasting and fairly low maintenance. However, there is a risk of fluids contaminating the air, making it a poor choice for critical applications like food or medical.

Oil-Sealed Rotary Vane

Oil-sealed rotary vane vacuum pumps utilize an eccentrically mounted rotor to compress the gas that is pulled in through the inlet port. It then is transferred to an exhaust valve that is spring-loaded to allow the gas to release when pressure builds higher than atmospheric pressure. They are called “oil-sealed” because oil is used to seal and cool the vanes.

Liquid Ring

Liquid ring vacuum pumps utilize vanes within the rotor that mix rotating rings of liquid to form the compression chamber seal. This is done very similarly to how rotary vane pumps operate. The only part of this machine that moves is the rotor, so these pumps are very low friction. Essentially, these are friction-free machines utilizing a rotating impeller to suck air into the pump, where it then is compressed with liquid, and then released. They are best suited for heavy-duty industrial applications and, unlike other vacuum pump types, can withstand these applications in wet environments.  

Dry Industrial Vacuum Pumps

Dry vacuum pumps may use some oil or grease within the gears or bearings, but already have tightly sealed clearances near the pump to keep fluid out of the air. This removes risk of contamination, making these units great choices for sensitive applications like food and medical.

Dry Claw

Dry claw vacuum pumps utilize twin rotors turning in opposite circles of each other that run next to each other but never come in direct contact with each other. Each time the rotor turns completely, gas is pulled into the compression chamber. The gas is then transferred between the suction end and the pressure end of the vacuum system, becoming compressed as the rotors turn and decrease the volume. The gas is then discharged. This type of vacuum pump is great for the packaging, printing, and wood processing industries and they boast a quieter and safer operation. These pumps can also handle harsh industrial environments.

Dry Screw

Dry screw vacuum pumps utilize two screw-shaped rotors, one threaded to the right and one threaded to the left. They turn at the same time in opposite directions, almost intertwining with each other but never touching, forming a very tight, frictionless clearance. As the screw rotors revolve, the suction port is enlarged, and the gas is then brought into the compressor chamber to move from suction side to pressure side. These pumps can also tolerate harsher conditions and environments.


Vacuum pumps are commonly measured in units called Torr or mbar.  A Torr is 1/760 of one standard atmosphere (atm) and an mbar is 1/1000 of a bar with standard atmospheric pressure is 1012.25 mbar.

Rough/Low Vacuum

1000 to 1 mbar / 760 to 0.75 Torr

This type of vacuum is commonly used in the lifting or transporting of materials.

Fine/Medium Vacuum

1 to 10-3 mbar / 0.75 to 7.5-3 Torr

This type of vacuum classification is commonly used to remove gas or liquid that has been absorbed into materials and for insulation purposes.

High Vacuum

10-3 to 10-7 mbar / 7.5-3 to 7.5-7 Torr

High vacuum is commonly used to help eliminate surface contamination, in some physics, and nuclear physics processes, and decorative plating.

Ultra-High Vacuum

10-7 to 10-11 mbar / 7.5-7 to 7.5-11 Torr

Ultra-high vacuum has some very specific common applications including scientific research uses like spectroscopy, high energy physics and nuclear physics processes, optics & electronics manufacturing, and eliminating contamination of surfaces. It can also be used for space simulations.

Extreme High Vacuum

<10-11 mbar / <7.5-11 Torr

Extreme high vacuum is common in advanced research and manufacturing applications like atomic physics and nano-technology.

Industries & Applications

Some common applications that Zorn provides vacuum solutions for include:

  • Packaging & Bottling
  • Drying
  • Picking & Placing
  • Degassing
  • Assembling
  • Medical



Zorn is the Midwest leader of custom, engineered compressed air and vacuum solutions. We provide the best customer experience by understanding your applications and needs and offering an unparalleled commitment to customer satisfaction. 

Our comprehensive product and service solutions keep you running 24/7.

  • Reliable equipment
  • Trusted brands
  • Seamless, easy installation
  • Post-sales support
  • Local, 24/7 service

Our compressed air experts look forward to meeting you to discuss your equipment and support needs. Please contact us directly at (262) 695-7000 with any questions or to schedule service for your system moving forward.

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