NSK Europe, the European arm of Japanese bearing producer NSK, has developed deep groove ball bearings that don’t require external lubrication to be used in submersible pumps dealing with cryogenic gases corresponding to hydrogen and LNG.
NSK has developed special shaft bearings with a cage produced from self-lubricating fluoroplastic for submersible pumps that deal with cryogenic gases and liquids.
The stainless-steel bearings with a cage manufactured from self-lubricating fluoroplastic are seeing rising adoption in submersible pumps as a growing number of tasks promote using hydrogen as an energy supply. These initiatives typically use particular submersible pumps that may reliably pump gaseous and liquid media in steady or intermittent operation at low temperatures all the means down to around -200°C.
In such pumps, the double bearing of the pump shaft is a crucial design factor. Corrosion resistance is important, and no lubricant can be utilized aside from the media washing around the bearing. However, this places powerful demands on the fabric pairing.
So NSK has developed a series of deep groove ball bearings particularly for these exceptional working conditions, and various other key design options provide differentiation from typical pump bearings. For instance, the internal and outer rings are manufactured from a stainless steel adapted to the special requirements of rolling bearings.
Piece of cake that occupies the complete inside volume of the bearing offers steering for the rolling components (also made from stainless steel), whereas the cage materials, a self-lubricating fluoroplastic, ensures low friction running of the bearing with out exterior lubrication. In addition, the high-performance fluoroplastic is extremely wear-resistant and offers good low-temperature properties at speeds up to 3600 rpm. The cage has a two-piece design, with the two halves joined by stainless-steel rivets.
The NSK bearings are available in various sizes (shaft diameter 30–100 mm) and are designed for use in both bigger hydrogen pumping services and decentralised functions, corresponding to hydrogen filling stations.
Share