NSK bearings deliver a guarantee of durability, speed and reliability, all of which serve to increase machine productivity and performance in paper mills worldwide. An example of this is in the wire section of modern papermaking facilities, water ingress together with the demand for ever-greater speeds can prompt premature bearing failure and potential production line stoppages.
However, NSK can offer an innovative product in the form of its Molded-Oil bearings, which are particularly effective in environments exposed to dust and/or water contamination. Alternatively, where ultra-high speeds are required, NSK has assisted numerous wire sections with its HPS range of spherical roller bearings.
Moving to the press section, where high loads and speeds mean the selection of a non-optimal bearing can cause failures such as raceway peeling, NSK offers its triple-ring bearings. These are available in either cylindrical/spherical roller bearing combination (2SL series) or spherical/spherical roller bearing configuration (2PSL series). The use of HPS spherical roller bearings with solid brass cages is a further option that is proven in press sections.
The dry end section of a paper mill not only features high loads and high speeds, but elevated temperatures of up to 150degC. As a consequence, the internal ring of bearings may become prone to breakage. To help eliminate this issue, NSK has developed TL series spherical roller bearings. Besides special heat treatment that guarantees high dimensional stability, the steel in the TL series features a chemical composition that makes the inner and outer rings very resistant to wear and cracking. Also available from NSK are cylindrical roller bearings with a self-aligning outer ring (RUB series) that prevent the problems of irregular wear and help withstand unpredicted skews. Like the wire and press sections, HPS spherical roller bearings are also a popular option in the dry end section, where they can be equipped with either a solid brass cage or a forged steel cage according to the selected dimensional range.
In the calender section, machine cylinders are subject to high loads and speeds which can lead to fatigue wear on spherical roller bearings and dilatation of the inner ring, while elevated temperatures can also cause failures. Here, the NSK TL-RUB series of cylindrical roller bearings has been developed so that calender rollers can expand thermally without restraints and therefore assure higher running accuracy and resistance to temperatures up to 200degC in continuous operation. Other calender section products available from the NSK portfolio are TL-standard spherical roller bearings, HPS spherical roller bearings and triple-ring bearings.
For more information about NSK bearings for the papermaking sector, please go to www.nskeurope.com.