Gas Jet Vacuum Pumps

Gas Jet Vacuum Ejectors are particularly suitable where no steam is available or where compressed air or gas as motive medium offer advantages over steam. They operate on the same principle as other ejectors.

Air jet vacuum pumps, sharing the characteristics of other gas jet vacuum pumps, use atmospheric air as motive medium. Backed by a liquid ring vacuum pump (which produces only an intermediate vacuum), the air jet vacuum pump can reach much lower suction pressure.

  • Low capital cost
  • No need for steam or compressed gas
  • Quick start-up and vacuum production
  • Removing the restriction of water ring vacuum pumps in reaching pressures below vapour pressure at the operating water temperature
  • Simple and reliable
  • Very easy installation
  • As start-up device for non-self-priming centrifugal pumps (for example on ships)
  • Suction of leak oil or petrol
  • in the nuclear industry in taking samples, dosing or for the continuous conveyance of small liquid flows
  • Evacuating pipelines, vessels and plants

Air jet vacuum pumps are used when

  • Suction pressure between  5 – 40 mbar is necessary
  • Cooling water at low temperature is available for economical operation of the water ring pump


  • No steam as motive is available


  • Low capital cost is more important than low energy consumption.

Combinations of water ring vacuum pumps and intermediate air jet vacuum ejectors are found in large numbers in different industries:

  • Chemical industry
  • Power production
  • Food processing
Range of Operation
    • Suction pressure air jet vacuum pump should be;
      • A single water ring vacuum pump: 50 to 100 mbar
      • Air jet vacuum pump/water ring pump combination: up to 5 mbar
    • Capacity: 0.1-4.0 kg/h
  • Cast iron
  • Cast stainless steel
  • Other materials on request
  • Steel or stainless steel
  • Temperature change resistant porcelain