The benefits of dry screw, liquid ring and rotary vane vacuum pumps.
by Uli Merkle
August 1, 2018

Both stages use a water jacket for cooling. Versions with once-through water cooling and water circulation are available. The cooling jacket controls the pump operating temperature needed for the specific application. The once-through water version controls the temperature by controlling the water flow with a temperature-controlled valve. The recirculating coolant version uses a thermostat to control the pump temperature.


  • high vacuum level
  • extremely robust and reliable
  • easy servicing
  • suited for conveying acid vapors and monomers or products that lead to polymerization when other vacuum technologies are used


  • operating fluids must be treated or correctly disposed of


It is important to consult with a vacuum expert and consider process conditions, process gases and integration into process control, as well as economic efficiency, safety and reliability. Often, these factors lead to a customized vacuum system that is tailored to the requirements.