Water jet cutting, paint removal and water hydraulics require small amounts of water with very high pressure. Traditionally this has been produced with piston pumps, which, however, are technically short-lived because of the poor lubricating properties of water.
In a high speed pump with water bearings the low viscosity of water is in fact beneficial: the bearing capacity is sufficient because of the high speed, and the friction losses stay reasonable. The pump type developed at LUT produces very high pressure in relation to the feed pressure, in other words there is very little cavitation. The pump also works at very low specific rotational speed with adequate efficiency.
Four prototypes of high speed pumps have been designed and built in the project in cooperation with High Speed Tech Oy Ltd ( turbine driven, electric motor driven, rotating- casing type and submersible-type pumps). The problem of high speed pumps in relation to piston pumps is, however, their higher cost and lower efficiency ratio. On the other hand there is very little need for servicing.