As an integral part of the wet end of a paper machine, felt roll bearings are subject to the ingress of corrosive contaminates during operation as well as wash down procedures. Contaminates reduce bearing life to months, yet the anticipated theoretical fatigue life is years for the applied loads and speeds. The reduction of bearing service life stems from the ingress of contaminates through the existing housing seals. To combat the ingress of contaminates in the field, felt roll bearings must be frequently lubricated to purge contaminates. In many cases, lubrication programs are also consolidating lubricants that are not suitable for felt roll applications. The end result is reduced bearing life and overall performance.

To increase bearing life, reliability and performance, contaminate must be kept out of the bearing. Better sealing is required while modification to existing roll and housing components must be kept to a minimum. To achieve this goal, an optimized spherical roller bearing with integral seals has been developed by NTN.

The bearing incorporates two robust contact seals, which complement any existing sealing currently utilized in the housing. Avoiding the ingress of contaminate prevents accelerated wear, limits lubricant deterioration, reduces lubricant requirements and hence extends lubricant intervals. The bearing package provides a specifically selected premium lubricant pre-filled at NTN’s manufacturing factory guaranteeing lubricant cleanliness, quantity and quality at installation.

When installation environments are also frequently less than ideal, a factory pre-lubricated sealed spherical roller bearing has proven extremely convenient during assembly. As these bearings are designed as a direct drop in replacement to the common ISO 223xx series bearings found in felt roll applications, they are completely compatible with existing roll designs and no modifications are necessary to the surrounding components.