Higher-specification bearings save EUR9000 per year

NSK's Hi-TF bearing steel has recently solved a costly problem at a European cement plant that was experiencing regular bearing failures on a high-temperature fan operating at 150degC. Typically, during an 18-month period, the original split bearings used on the fan would fail at least three times, which was considered unacceptable.

Examination of the application and the split bearings revealed that a combination of high temperature and heavy load was causing the premature failures. As a solution to this problem, NSK recommended the use of Hi-TF spherical roller bearings mounted in plummer blocks fitted with labyrinth seals. This combination is capable of continuous operation at 200degC under heavy loads. The result has been a cost saving of EUR9130 per annum on the operation of the fan.

Hi-TF is able to provide this much improved performance as a result of its unique microstructure, which is able to relax the stress concentrations on the edges of indentations on the bearing surfaces. This microstructure - a material with a high volume of retained austenite and a high hardness - produces a longer life even under conditions where there is an insufficient oil film and surface damage occurs - such as peeling. In addition, Hi-TF bearings offer increased resistance to wear and seizure as a result of the dispersion of large number of fine carbides and nitrides in the bearing material. In comparative tests with bearings made of conventional materials, such as SUJ2 steel, the Hi-TF material structure has shown less than one-third the rate of wear and a 20 per cent increase in resistance to seizure.

Contact NSK for more information about Hi-TF bearings or use the form on this page.