Vacuum pump
Two claw-shaped rotors turn without contact or lubricant in the chamber. Oil-free.
Typical range
3–30 HP, down to 50 mbar (1.5 inHg abs)
Best for
Food, pharma, central vacuum systems, applications that can't tolerate oil.
Operating principle
Two claw-shaped rotors rotate without contact, drawing gas in and compressing it to discharge. No oil in the chamber; timing gears (oil-lubricated, sealed) synchronize the rotors.
Efficiency notes
Oil-free, good for mid vacuum. Sensitive to particulate ingestion. VSD is common for energy matching.
Selection guidance
Food, pharma, central vacuum where oil can't be tolerated. Always protect with an inlet filter.
Components
- Two claw rotors
- Timing gears (oil-lubricated, sealed)
- Air-cooled jacket
- Inlet & exhaust silencers
- VSD (common)
Common issues
- Loss of vacuum → debris ingestion damaging rotors (always use inlet filter)
- Timing gear oil contamination → seal failure between gearbox and chamber
- High discharge temp → blocked cooling air path
Maintenance
- Annual: change gearbox oil, inspect inlet filter, check shaft seals
- Keep inlet filter spotless — claws have zero tolerance for solids
Field tips
- Inlet filter spotless — claws have zero tolerance for solids
- Timing-gear oil seal failure lets oil into the chamber — inspect annually
- VSD pairing saves energy on variable vacuum demand