[Differences Between Air Pumps and Liquid Pumps]
The external dimensions, motor, pump head, and rubber material used in Nidec diaphragm pumps are exactly the same for both the air pump and liquid pump models.
The only difference lies in the connecting rod and the cam located between the motor and the pump head (see the parts highlighted in red in the image below).
The air pump has a longer connecting rod and a larger cam; the liquid pump has a shorter connecting rod and a smaller cam. Consequently, during operation, the air pump produces a greater deformation/squeeze on the rubber diaphragm chamber with each motor revolution.
[When the medium is gas]
- Air Pump: Flow rate > 1.1 L/min, Maximum vacuum > -40 kPa, Maximum positive pressure > 90 kPa.
- Liquid Pump: Flow rate 340~600 ml/min, Maximum vacuum ≈ -20 kPa, Maximum positive pressure ≈ 25 kPa.
[When the medium is liquid]
- Air Pump: Flow rate ≈ 600 ml/min.
[Recommendation]
Given that the diaphragm chamber of the air pump undergoes greater deformation per cycle, to ensure the pump's service life, it is recommended to operate a 24V air pump at 12V when used for liquids (user tests have shown a lifespan exceeding 5,000 hours under this condition).
[Conclusion]
Nidec diaphragm air pumps can be used as liquid pumps, offering a self-priming height of over 4 meters and strong suction.
[Successful Case]
In IVD (In-Vitro Diagnostic) equipment, many users employ NIDEC air pumps for waste liquid drainage because the stronger suction ensures more complete removal.