Reference

Positive displacement using pistons driven by a crankshaft. Single or two-stage.

Two intermeshing helical rotors compress air continuously. Oil-flooded or oil-free.

Two interleaved spiral scrolls — one fixed, one orbiting — compress air with minimal vibration.

No lubricant in compression chamber. Uses PTFE rings, coated rotors, or dry running design.

Multi-stage reciprocating designs that produce 500–6,000+ PSI for PET, breathing air, paintball, CNG.

Impeller accelerates air radially; a diffuser converts velocity to pressure. Oil-free by design, high CFM.

A flexing diaphragm draws and displaces air through check valves. Oil-free, hermetic, low flow.

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

Two figure-eight lobes move air without internal compression. Low pressure, high flow.

Impeller recirculates air through a side channel, building pressure in stages. Oil-free, compact.

Claw rotors run without contact or chamber oil. Oil-free discharge, mid pressure.

Oil-sealed sliding vanes in an offset rotor generate vacuum. Most common industrial vacuum pump.

Two claw-shaped rotors turn without contact or lubricant in the chamber. Oil-free.

Rotating impeller throws sealant liquid (usually water) into a ring that compresses gas. Handles wet, dirty, condensable loads.

Two non-contact screw rotors compress gas without oil in the chamber. High capacity, deep vacuum.

Reciprocating piston draws gas to create vacuum at the inlet. Oil-lubricated or oil-free.

Diaphragm flexes to draw/discharge gas through check valves, isolated from the drive. Oil-free, clean.

Pressure vessel that stores compressed air, dampens pulsation, and buffers demand swings against compressor capacity.

Pressure-actuated valves that open to vent overpressure, protecting vessels and systems from rupture.

Check valves hold receiver pressure; unloader valves bleed head pressure on shutdown so the compressor restarts unloaded.

Filters that remove particulate from intake air to protect valves, rotors, rings, and downstream air quality.

Rotating seals contain oil/air; bearings carry rotor/shaft loads. The two dominant wear items in any compressor.

Heat exchangers that remove compression heat — intercoolers between stages, aftercoolers after discharge — to cut power, condense moisture, and protect downstream equipment.

Pressure, flow, vacuum, and power units used across compressed air and vacuum — with conversions and instrument notes.