Iron and steel industry

STF is the specially developed bearing steel for high loading. It undergoes a unique heat treatment process developed by NSK to optimise the level of retained austenite in the bearing material. STF has a very fine-grained structure. This combination provides greater durability, especially during operation in contamined environments with insufficient lubrication.
 
The service life is extended compared to standard steel. It is five times longer in more contamined lubricant grease and approximately twice as long in less contamined lubricant grease.

 

DNV GL certifies NSK’s Super TF bearing material
Of direct relevance to the wind energy sector, international accredited registrar and classification society DNV GL has confirmed that roller and ball bearings made of NSK’s Super TF material exhibit significantly higher dynamic load ratings. Such is the effect of the higher load rating that bearing service life is effectively doubled in wind turbine applications. The verification confirmed NSK's published specifications and, in a Statement of Conformity on the 15 November 2017, certified that when Super TF is used, the basic dynamic load rating can be improved by 23% in roller bearings and 26% in ball bearings. This is equivalent to a doubling of bearing fatigue life in comparison with ordinary bearings.

 

Four-row tapered roller bearing STF in reversible quarto-stands displays a bearing life of 7,530 hours. This is about ten times longer than a standard bearing and about three to four times longer than other premium-brand bearings.

SWR (Super Wear Resistant) bearing steel is specially developed for continuous casting operations. The fine structure of evenly distributed carbides and carbonitrides significantly increases wear resistance. The controlled amount of residual austenite eliminates damage due to flaking, thus substantially prolonging bearing life. Increasing the core toughness against fracturing prevents cracks.

 

Improved wear resistance – three times better than AISI 52100 bearing steel.

Extended flaking life – five times longer than to AISI 52100.

Extended crack operation time – five times longer than AISI 52100

WTF bearing steel is specially developed for rolling mill bearings. It ensures a longer bearing life by preventing premature flaking and cracking under severely contaminated conditions of water-infiltrated grease lubrication. The increased reliability and longer service life significantly reduce maintenance costs.

 

showed that WTF bearing life is three times longer than that of conventional bearings.