Vacuum technology
Diaphragm
Oil-free, sealed, compact. Lab and OEM workhorse.
Schematic section, not to scale
How it works
Diaphragm pumps move gas with a flexing membrane driven by a connecting rod, so the gas never touches a lubricated part. They are small, clean and often run as vacuum or pressure pumps inside analysers, medical devices and laboratory equipment.
An eccentric on the motor shaft moves a connecting rod that flexes the diaphragm up and down. Inlet and outlet valves open and close with each stroke, drawing gas in and pushing it out; heads can be staged or run in parallel.
Performance range
Fractional flows to a few hundred l/min; vacuum typically to roughly 2-100 mbar(a) depending on stages
Typical industry range. Exact capability is model specific, see each model’s curve.
In the catalogue · 232 models from 5 manufacturers
- Pumping speed
- 0.0198 – 19.3 m³/h · 220 models
- Ultimate pressure
- 0.3 – 600 mbar · 179 models
- Max. pressure
- 0.1 – 12 bar · 144 models
- Weight
- 0.66 – 26 kg · 85 models
- Motor power
- 0.01 – 0.4 kW · 15 models
- Max. vacuum
- 65 – 85 % · 5 models
Spread of each model’s own rated figure, as published by its manufacturer.
Advantages & tradeoffs
- Oil-free, contamination-free gas path
- Compact and quiet
- Hermetic gas path suits sensitive or aggressive gases
- Limited flow
- Diaphragm and valve wear
- Ultimate vacuum limited by valves and staging
Best applications
Maintenance
Diaphragm and valve replacement at intervals; keep inlet filters clean.
Energy characteristics
Specific-energy comparisons (kW per unit of flow at your operating point) appear here as sourced performance curves are added. Until then, compare models directly on the Performance Map.
Open the Performance Map