construction pits.This pump type operates without a foot valve and without an evacuation device on the suction side. The pump has to be primed with the fluid to be handled prior to commissioning. Two-phase mixture is pumped until the suction line has been evacuated and the fluid level has been pushed into the front suction intake chamber by atmospheric pressure. During normal pumping operation this pump works like an ordinary centrifugal pump. See also Centrifugal compressor Axial flow pump Net positive suction head (NPSH) Pump Seal (mechanical) Specific speed (Ns or Nss) Thermodynamic pump testing Turbine Turbopump References Sources ASME B73 Standards Committee, Chemical Standard Pumps External links Pumps Gas compressors Turbines Hydraulic engineering Power engineering Articles containing video clips