Page 62 - North American Clean Energy March/April 2020 Issue
P. 62

     wind power
  Engineered Coatings for Roller Bearings Help Avoid Costly Repairs
by Vikram Bedekar and Doug Lucas
bearings are subject to severe operating conditions. Volatile winds, extreme weather, and variable load scenarios can challenge the limits of bearing performance and reliability, particularly as turbines grow taller and more powerful. Bearing makers have responded with optimized designs for popular wind platforms; where added protection against mechanical wear is paramount, the industry offers engineered coatings that can stand up to the toughest environments on earth.
Reducing Friction
Steel-to-steel contact is the trigger for virtually all bearing-related issues in wind turbines. This is largely due to the difficulty of maintaining an adequate lubrication film in mainshaft and gearbox bearings, even where operating conditions are ideal. The demands of wind energy production put incredible stresses on bearings that can degrade lubricating greases and oils—without proper maintenance, costly problems can develop.
Many wind farm operators have felt the financial sting of a major corrective event when critical bearings fail to reach their target service life. More than a decade ago, as maintenance issues mounted, the wind industry grew aware of a wider trend: turbines
designed for a 20-year life cycle often required bearing repair or replacement within just 10 years. What became evident is that modern multi-megawatt towers demanded more robust bearing solutions compared to older models. This led manufacturers to introduce new bearings built for the rigors of commercial-scale energy production. It also sent bearing makers down a path to improving performance in other ways, including
the use of engineered coatings.
Becoming Less Steel-Like
One novel approach to coating technology traces back to the late 1990s, when scientists theorized that making the surface of bearing rolling elements less “steel-like” could effectively neutralize
the adhesive wear, which is what happens when metal rollers and raceways come
in contact (leading to fretting wear and/
 Since 1983
 Take Your Skills Higher
Enroll in One of Our Two Intensive, Hands-On
Windblade Repair Courses
Composite Windblade Repair & NEW Advanced Windblade Repair
   Common Damage on 3-Point Mount SRB MS Bearings
 1.3 MW 1.0 MW 2.3 MW
1.25 MW 1.65 MW 1.5 MW

   60   61   62   63   64