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.
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