ABSTRACT
A chip conveyor belt return roller bearing installed in a pulp
plant presented premature failures due to misalignment and
contamination, causing a Mean Time Between Repair (MTBR)
of around three months. The conveyor belt carries wood chips to
process, therefore, great reliability and availability is required to
avoid a decrease in production and high maintenance cost. In order
to increase equipment MTBR, the original bearing arrangement
was evaluated in terms of application, which comprised Deep
Groove Ball Bearings and Cylindrical Roller. From that study,
a change from the original bearing arrangement to two Sealed
Spherical Roller Bearings (SSRB) was proposed, which presented
less sensitivity to system misalignment compared to the original
arrangement. A Three-Barrier Solution was also implemented,
an efficient solution against solid particles contamination in
those components. This approach has been widely and efficiently
applied in several equipment, mainly in bearing conveyor belts.
After implementation of the SSRB arrangement solution, bearing
life reached 24 months and, so far, the system has not presented
failures. Therefore, in operational equipment conditions, bearing
relubrification of was eliminated, contributing to worker safety
since the environment has solid particles in suspension; as well
as increased equipment reliability and availability for production
process.
Keywords: Bearing arrangement, Three-Barrier Solution,
sealed bearing, belt conveyor.