Features of EWN-A series

This type equips automatic air vent mechanism. An air vent valve builtin pump chamber enables reliable air venting. Also equipped manual air vent valve enables easy pressure release in discharge piping. Gaseous liquid such as sodium hypochlorite or hydrogen peroxide can be injected without gas locking.

  • Entrained air is automatically expelled from the pump head. No special degassing is needed.
  • The pump immediately resumes operation without gas lock even after a long period of stoppage.
  • Use the air vent port manually for quick release of discharge line pressure.
  • Capable of pumping concentrated sodium hypochlorite.

Principle of operation

Air which comes from suction port goes to the connection adapter through pump head. Because pump discharge side is pressurized, air goes to the automatic air vent valve which the pressure load is lower than pump discharge side, and goes out little by little together with liquid.
Once the pump gets out of locked air condition, it returns to normal operation to discharge the liquid. A ittle bit of liquid is discharged from automatic bleed valve, too.


Max. discharge capacity range 30 – 110 mL/min
Max. discharge pressure range 0.7 – 1.0 MPa
Main materials PVC
Stroke rate 1 – 360 spm
Power supply 100 – 240 VAC, 50/60 Hz
Liquid temperature range −10 – 40˚C
Viscous liquid Please contact us for details.
Slurry liquid Can not be handled.

Product information

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