NSK Europe, the European arm of Japanese bearing producer NSK, has developed deep groove ball bearings that do not require external lubrication to be used in submersible pumps dealing with cryogenic gases such as hydrogen and LNG.
NSK has developed particular 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 increasing adoption in submersible pumps as a growing variety of initiatives promote the use of hydrogen as an energy source. These projects often use particular submersible pumps that may reliably pump gaseous and liquid media in steady or intermittent operation at low temperatures down to round -200°C.
In such pumps, the double bearing of the pump shaft is a important design factor. Corrosion resistance is essential, and no lubricant can be used apart from the media washing around the bearing. However, this places powerful demands on the fabric pairing.
So NSK has developed a sequence of deep groove ball bearings particularly for these distinctive working conditions, and several key design features provide differentiation from standard pump bearings. For example, the inner and outer rings are manufactured from a chrome steel tailored to the special necessities of rolling bearings.
A stable cage that occupies the whole inner volume of the bearing provides steerage for the rolling parts (also made of stainless steel), whereas the cage materials, a self-lubricating fluoroplastic, ensures low friction working of the bearing with out external lubrication. In addition, the high-performance fluoroplastic is extraordinarily wear-resistant and provides good low-temperature properties at speeds as much as 3600 rpm. diaphragm seal has a two-piece design, with the 2 halves joined by stainless steel rivets.
The NSK bearings can be found in numerous sizes (shaft diameter 30–100 mm) and are designed for use in each bigger hydrogen pumping facilities and decentralised purposes, such as hydrogen filling stations.
Share