Vacuum pump
Reciprocating piston draws gas to create vacuum at the inlet. Oil-lubricated or oil-free.
Typical range
0.5–10 HP, down to ~0.05 mbar (two-stage oil-sealed)
Best for
Small packaging, lab, vacuum forming, intermittent vacuum.
Operating principle
A reciprocating piston draws gas through an intake valve and discharges it through an exhaust valve, creating vacuum at the inlet. Oil-lubricated or oil-free variants; single or two-stage.
Efficiency notes
Good ultimate vacuum for the cost; two-stage is deeper. Intermittent duty is typical.
Selection guidance
Packaging, lab, and small systems where oil tolerance is OK and cost matters.
Components
- Piston & rings
- Cylinder
- Intake/exhaust valves
- Crankcase (oil)
- Exhaust mist filter
Common issues
- Oil backstreaming toward process → exhaust/mist filter needed
- Valve failure → loss of vacuum
- Low ultimate vacuum → worn rings, oil contamination
Maintenance
- Oil changes per OEM
- Valve inspection
- Exhaust mist-filter replacement
Field tips
- An exhaust mist filter prevents oil backstreaming to the process
- Worn rings and dirty oil are the top two causes of lost vacuum
- Two-stage reaches far deeper vacuum than single-stage