C2-Sewage Pumps DN 32 to DN 600 - 2008.pdf

Sewage Pumps for Municipal and Industrial ApplicationsPlanning GuideVortex impeller• Minimum inclination to clogging• Gap seals not required• Suitable for some bubble-forming fluids• Power correction possible by trimming theimpeller• Low efficiency• For solid matter concentrations up to 8% TS,depending on the type of sludgeDry sump installationPropeller impeller• For very high flows at low delivery head• Only suitable for fluids with little contamination(e.g. for rainwater, return sludge, circulationof activated sludge, pumping stations,etc.)Installation typesFundamentally, three installation types are distinguished:Wet sump installationIn the case of dry sump installation, the operating space and collectingshaft are spatially separated. The pump is set up dry in the operatingspace, and is therefore accessible at all times. The fluid is fedthrough a suction line.Portable installationWith the wet sump installation, the unit is surrounded by the fluid.The pump is connected to the existing pipeline system via a permanentlyinstalled suspension unit. By means of the associated loweringsystem, this can be lifted any time even when the shaft is full, or belowered into the shaft.With the portable installation, the pump is equipped with a pedestaland can be flexibly put to use. Usually, these units are designed with aplug and/or switchgear. A bare cable end is also possible, however.142 Subject to change without prior notice 09/2007 WILO AG