Surface Treatment

Cleaned and Dried CR

Prior to assembly, the pump components are washed in pure, hot soap water, rinsed in de-ionized water, and dried. Because the parts are dried prior to assembly the pumps are not performance tested. The pumps are wrapped in a plastic bag before being packaged.


Electropolished CR

To substantially reduce the risk of corrosion of the materials and improve the cleanability Grundfos can offer electropolished CR pumps. The pump incorporates a standard shaft seal which has not been electropolished. Electro-polishing removes burrs as well as metallic and non-metallic inclusions, providing an extremely smooth, clean, and corrosion-resistant stainless steel surface. First, all components are pickled in a mixture of nitric acid and hydrofluoric acid. Subsequently, the components are electropolished in a mixture of sulphuric acid and phosphoric acid. Finally the components are passivated in nitric acid. The CRN 1s, 1, 3, 5, 10, 15, and 20 cast parts are all mechanically polished before being electropolished.


  • Pharmaceutical industry
  • Food industry
  • Electronic industry




Silicon reduced CR

Silicon reduced pumps are suitable for processes requiring the use of pumps not containing silicon. A silicon reduced pump differs from a standard pump in the following ways: only FKM rubber is used, all components, except the electric motor, are washed in “DX 380 Low-Voc cleaner”, spare parts ordered together with the pump are also washed in “DX 380 Low-Voc cleaner”, the pump is assembled in a room separate from the production area (not a clean room), tools used for the assembly of the pump do not contain silicon, the assembled pump is checked visually, performance is not tested, the pump is wrapped in silicon-free plastic before being packaged.


  • Production of paint and varnish
  • Cleaning processes in the electronics industry


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