Oil-Sealed vs. Dry Vacuum Pumps: Choosing the Right Technology for Your Application
Industrial vacuum pumps are essential across manufacturing, pharmaceuticals, electronics, food packaging, and energy production. However, not all vacuum pumps are created equal—and choosing the wrong type can mean higher energy costs, more frequent maintenance, and even process contamination.
Two of the most common categories are oil-sealed vacuum pumps and dry vacuum pumps. Each has unique strengths and ideal applications. In this blog, we’ll break down the differences between these two technologies, help you understand which is best for your operation, and highlight how Atlas Copco’s innovative vacuum solutions offer unmatched performance.
📞 Need expert advice on vacuum pump selection? Call Industrial Air Services at (615) 641-3100 for service across Nashville, Knoxville, and Chattanooga.
What Are Oil-Sealed Vacuum Pumps?
Oil-sealed vacuum pumps (such as rotary vane and rotary screw designs) use a thin film of oil to seal, lubricate, and cool internal components. The oil also helps maintain a consistent vacuum level and reduces internal leakage.
Atlas Copco’s GHS VSD⁺ series is a prime example of modern oil-sealed rotary screw vacuum pumps.
Key Features:
High ultimate vacuum levels (down to a few millibar absolute)
Efficient cooling and sealing properties from oil
Excellent for processes with demanding vacuum stability requirements
Long service intervals when properly maintained
Oil-sealed pumps have traditionally been the workhorses of industrial vacuum, offering robust performance in applications where contamination risks are low or manageable.
What Are Dry Vacuum Pumps?
Dry vacuum pumps achieve vacuum without any oil or liquid in the compression chamber. Designs include dry screw, dry claw, scroll, and multistage roots pumps.
Atlas Copco’s DWS VSD⁺ and DZS Claw Series pumps are leading examples of dry vacuum solutions.
Key Features:
No risk of process contamination by oil
Lower maintenance and operating costs
Environmentally friendly operation (no oil disposal required)
Excellent for cleanroom and sensitive manufacturing environments
Dry vacuum pumps have surged in popularity due to stricter contamination controls, sustainability goals, and lower total cost of ownership.
When to Choose Oil-Sealed Vacuum Pumps
Oil-sealed technology remains the best choice for certain applications where:
High vacuum levels are critical (below 1 mbar)
Fluctuating loads are minimal
Moderate contamination risk is acceptable
Cost-conscious operations are important
Common industries and applications:
Plastics extrusion
Vacuum packaging
CNC woodworking
Bottle filling
Automotive vacuum impregnation
Atlas Copco’s GHS VSD⁺ series delivers energy-efficient, oil-sealed performance with integrated VSD technology—optimizing performance while cutting energy use up to 50%.
When to Choose Dry Vacuum Pumps
Dry pumps are the clear winner when:
Oil contamination cannot be tolerated (pharma, semiconductor)
Clean environments like ISO Class cleanrooms are required
Energy savings and sustainability are top priorities
Frequent cycling and load variation are common
Common industries and applications:
Pharmaceutical manufacturing (coating, freeze drying)
Semiconductor and electronics (wafer fabrication)
Food packaging (MAP packaging, dairy filling)
Battery production (lithium-ion cells)
Research labs and biotechnology
Atlas Copco’s DWS VSD⁺ dry screw pumps and DZS dry claw pumps offer rugged, oil-free performance ideal for sensitive processes.
Why Variable Speed Drive (VSD⁺) Changes the Game for Both Types
Whether you choose oil-sealed or dry, Atlas Copco’s VSD⁺ technology delivers major benefits:
Energy savings up to 50%
Quieter operation
Lower heat output
Extended equipment life
Built-in smart control and remote monitoring
By automatically adjusting the motor speed based on demand, VSD⁺ minimizes waste and protects your investment.
Real-World Example: Choosing the Right Pump in Food Processing
A meat processing plant needed vacuum pumps for two very different parts of its facility:
Packaging area: Required moderate vacuum for modified atmosphere packaging (MAP) with frequent cycling.
Brine injection station: Required strong, steady vacuum for marination and injection.
Solution: They installed DZS dry claw pumps for the packaging line to eliminate oil contamination and maximize cycling efficiency. For the brine injection system, they installed GHS VSD⁺ oil-sealed rotary screw pumps to ensure strong, stable vacuum at maximum energy efficiency.
Result:
38% energy savings across the vacuum system
Zero contamination issues
Reduced maintenance frequency by 40%
📞 Need a custom recommendation like this? Call Industrial Air Services at (615) 641-3100.
How Atlas Copco Supports Both Technologies
Atlas Copco’s vacuum solutions include:
Oil-Sealed Systems: GHS VSD⁺ rotary screw, LRP VSD⁺ liquid ring pumps
Dry Systems: DWS VSD⁺ dry screw, DZS dry claw pumps, DHS 065-200 VSD⁺ dry screw pumps
Connectivity: GENIUS Instant Insights™ and HEX@™ smart control
Custom Systems: Engineered Systems + Solutions for complex applications
By offering both oil-sealed and dry options—with VSD⁺ as standard—Atlas Copco ensures customers get the best match for their needs.
Final Tips for Choosing the Right Vacuum Pump
Analyze your process requirements carefully: Is ultimate vacuum, contamination control, or energy savings the top priority?
Consider total cost of ownership, not just upfront purchase price.
Factor in maintenance schedules, spare parts, and service availability.
Look for systems with built-in monitoring to protect your investment.
Partner with an expert distributor who can size and configure your system properly.
Conclusion
Choosing between oil-sealed and dry vacuum technology is one of the most important decisions you’ll make for your industrial process. With Atlas Copco’s broad portfolio of GHS, DWS, and DZS pumps—and expert support from Industrial Air Services—you can be confident you’re selecting a vacuum solution that maximizes reliability, minimizes costs, and supports your future growth.
This blog is proudly provided by Industrial Air Services, your trusted source for Atlas Copco vacuum systems in Nashville, Knoxville, and Chattanooga.
📞 For help sizing and selecting your next vacuum pump, call (615) 641-3100 today.
