NSK develops self-lubricating rolling bearings

NSK Europe, the European arm of Japanese bearing producer NSK, has developed deep groove ball bearings that do not require external lubrication for use in submersible pumps dealing with cryogenic gases such as hydrogen and LNG.
NSK has developed particular shaft bearings with a cage created from self-lubricating fluoroplastic for submersible pumps that handle cryogenic gases and liquids.
The stainless-steel bearings with a cage made of self-lubricating fluoroplastic are seeing growing adoption in submersible pumps as a growing number of projects promote the use of hydrogen as an power supply. These tasks usually use special submersible pumps that can reliably pump gaseous and liquid media in continuous or intermittent operation at low temperatures down to round -200°C.
In such pumps, the double bearing of the pump shaft is a crucial design factor. Corrosion resistance is essential, and no lubricant can be utilized apart from the media washing around the bearing. However, this places tough calls for on the material pairing.
So NSK has developed a series of deep groove ball bearings specifically for these exceptional operating conditions, and several other key design features provide differentiation from standard pump bearings. For instance, the inside and outer rings are made from a stainless-steel adapted to the particular requirements of rolling bearings.
Outlawed that occupies the whole inside volume of the bearing supplies guidance for the rolling elements (also manufactured from stainless steel), whereas the cage materials, a self-lubricating fluoroplastic, ensures low friction running of the bearing without exterior lubrication. In addition, the high-performance fluoroplastic is extraordinarily wear-resistant and provides good low-temperature properties at speeds as much as 3600 rpm. The cage has a two-piece design, with the two halves joined by stainless-steel rivets.
The NSK bearings are available in numerous sizes (shaft diameter 30–100 mm) and are designed for use in both bigger hydrogen pumping services and decentralised applications, such as hydrogen filling stations.

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