This is the fourth installment of a 5 part series on bearing trends.
By David R. Mikalonis
4. SPECIALTY COATINGS
Coating options can enhance levels of protection for a bearing or perform other functions to promote longer service life in an application. The number of coating options continues to trend upward.
Example: For all types of critical bearings in wind turbine systems, a black oxide coating is trending – formulated to provide a surface layer of protection for higher reliability and performance against widely varying temperatures, speeds, and loads, and to resist contaminants, moisture, and chemicals that otherwise could limit bearing lifecycles. Such coated bearings can be introduced into new installations or serve as replacement upgrades.
The black oxidation surface treatment is applied to a bearing’s rings and/or rollers. Up to 15 different immersion steps create a thin, dark black surface layer delivering a performance upgrade.
Black oxide bearings can increase turbine uptime by enhancing resistance to corrosion and smearing; improving performance in low-lubrication conditions; limiting risk of fretting, micropitting, and cracking; reducing potential damage from aggressive oil additives; and reducing the effects of friction and wear.