NSK Develops 7th Generation Low-Friction Tapered Roller Bearings

Helping to improve fuel/electricity efficiency in all forms of mobility: ICE, HEV, PHEV, and EV 

● Reduces rolling friction by optimizing the number of rollers　

● Improves fuel/electricity consumption across the entire range of automobile speeds by achieving an average 20% reduction in friction over the entire rotation speed range

● New optimization technique for the number of rollers also applied to existing models of low-friction tapered roller bearings

● NSK aims to achieve annual sales of 15.0 billion yen by 2030

　NSK Ltd. has developed its 7th generation of low-friction tapered roller bearings. This product can help to increase vehicle range through improved fuel/electricity consumption achieved by reducing friction by an average 20% over the entire rotation speed range. NSK aims to achieve annual sales of 15.0 billion yen by 2030 for this product, including existing models.

1.    Background

　Tapered roller bearings are frequently used when there are low-rotation speed, high-load conditions on the tire side. Therefore, reducing the amount of friction in the roller bearings can help to increase the efficiency of the power train unit.

Since around 1980, NSK has used various methods to decrease friction in tapered roller bearings. In recent years, the rapid advance of automobile electrification in pursuit of a decarbonized society has increased the need to reduce friction. Moreover, Japan's adoption in 2017 of the WLTC1 (a standard international method for measuring fuel economy), has made it necessary to further improve fuel economy. Therefore, tapered roller bearings also need to deliver low friction across the entire rotation speed range.

1 WLTC: Worldwide harmonized Light vehicles Test Cycles, an international method for measuring fuel economy, which began to be adopted in Japan by the Ministry of Land, Infrastructure, Transport and Tourism in 2017. Under the previous method of determining fuel economy values (JC08 cycle), the average fuel consumption was measured as an average over the entire range of low to high vehicle speeds. However, under the WLTC cycle, it is measured at each vehicle speed: in the city, in the suburbs, and on highways.

2. Features

1) Optimization of the number of rollers reduces rolling friction, achieving an average 20% reduction in friction over the entire rotation speed range

2. Features

1) Optimization of the number of rollers reduces rolling friction, achieving an average 20% reduction in friction over the entire rotation speed range