Smaller and lighter bearings with high-temperature dimensional stability and improved wear resistance

 

-NTN provides solutions for the automotive field, including electric drive units, transmissions, and compressors for electric and hybrid vehicles (EVs and HEVs).

 

NTN Corporation (hereinafter referred to as NTN) has developed the ‘HA-C Bearing’ by applying its self-developed special heat treatment technology ‘HA-C*1’ to the deep groove ball series, and has officially launched it in the automotive field.

‘The HA-C Bearing adopts the ’HA-C" technology, which enables the industry's largest load capacity, and has succeeded in achieving a compact and lightweight bearing. This product will contribute to energy saving and emission reduction in the automotive field by providing solutions for e-Axle drive units for electric and hybrid vehicles (EVs and HEVs), transmissions for HEVs and fuel vehicles, and compressors.

 

 

Size comparison of ‘HA-C bearing (left)’ and conventional product (right)

 

 

Example of application in parallel axis e-Axle (in red circle)

 

 

 

‘HA-C’ is a special heat treatment technology developed independently by NTN that maximises the surface hardness of bearings and achieves high load capacity by allowing hard elements to be dispersed in the material in a greater and more stable manner.

 

The HA-C bearing, which uses this technology, has a reduced outer diameter of approximately 15%, a reduced width of approximately 30%, and a weight reduction of approximately 55%*2 while maintaining the same life span as conventional products, meeting the demand for smaller and lighter bearings for various types of automotive drives such as e-Axle and transmissions.

 

In addition, in order to save fuel and electricity, lubricants for drives are being developed in the direction of low viscosity with the aim of reducing frictional torque. However, low-viscosity lubrication environments make bearing components susceptible to direct metal contact, resulting in shorter bearing life and increased wear. At the same time, bearings are also more susceptible to internal damage caused by foreign objects in the oil. The HA-C Bearing can cope with these harsh environments by not only providing long life, but also by being more resistant to foreign matter and wear.

 

Since the release of this technology in May 2024, NTN has received numerous inquiries and requests for the HA-C technology to achieve compactness, lightweighting and long life, and has been promoting the development of bearings using this technology, and now that performance verification and other processes have been completed, we are officially launching the marketing of the ‘HA-C Bearing’.

 

NTN will promote the HA-C Bearing as a core product that can be used in automobiles such as e-Axle to achieve compactness, light weight and high efficiency, and will contribute to energy conservation in automobiles. At the same time, we will also take advantage of the product's strengths to actively expand its application scenarios and promote the technology to a wider range of fields beyond automobiles.

 

 

Product Features (Comparison with NTN Standard Bearings)

 

01｜High load capacity

Static load capacity has been increased by 2 times, and rolling fatigue life under heavy load conditions has been extended by more than 8 times*3 High load capacity design enables smaller and lighter bearings

(Alternative case: bearing outer diameter reduced by about 15%, width reduced by about 30%, weight reduced by about 55*2)

 

02｜Foreign Matter Resistance

Rolling fatigue life can be more than 4 times as long under foreign matter lubrication environment*3

 

03｜Dimensional stability at high temperature

The long-term dimensional change rate at 150℃ ambient temperature is reduced to less than 1/2.

 

04｜Wear resistance

Wear reduced to less than 1/300*4

 

1)HA-C: High Antiwear and Capacity

2)For catalogue standard series. Further size reduction is possible for special sizes.

3)Additional validation has resulted in further improvement over the values at the beginning of development.

4)Based on NTN test results under severe lubrication conditions.