Rotary Tooth (Oil-Free)

All reference
Compressor

Two meshing tooth-shaped rotors compress air without contact or chamber oil. Two-stage for plant air.

Typical range
15–300 HP, to ~150 PSIG (two-stage oil-free)
Best for
Oil-free plant air, food/pharma/electronics mid-scale.
Operating principle

Two intermeshing tooth-shaped rotors compress air without contact in the chamber (oil-free). Timing gears synchronize them; multiple stages reach higher pressure. Interstage coolers manage heat.

Efficiency notes

Oil-free, two-stage to ~150 PSIG. Moderate efficiency; staging improves it. Good for mid-range oil-free plant air.

Selection guidance

Oil-free plant air (food, pharma, electronics) where a dry screw is too costly and a centrifugal too large. Mid CFM.

Components
  • Twin tooth rotors
  • Timing gears
  • Interstage cooler
  • Synchronizing coupling
  • Air/water cooling
Common issues
  • Rotor contact from timing-gear failure → catastrophic
  • High discharge temp → cooling loss, fouling
  • Capacity loss → worn rotor clearances
Maintenance
  • Timing gear oil per OEM
  • Interstage cooler cleaning
  • Vibration monitoring — gear/bearing health
Field tips
  • Timing-gear failure causes rotor contact — protect the gear train
  • Interstage cooler fouling raises discharge temp fast
  • Vibration trending catches gear and bearing faults early