NSK'S EMM-VS Series of vibratory bearings offer 30% higher load ratings and up to twice the life of conventional designs

NSK has introduced the EMM-VS Series of cylindrical roller bearings (CRB) for Vibrating Equipment. The bearings have a 30% higher load rating compared to conventional CRB bearings and offer up to twice the bearing life. These performance advantages mean that, in many applications, bearings can be downsized to reduce costs without affecting machine performance or bearing life.

The EMM-VS Series bearings are available in standard ISO sizes, and are designed for use in gearboxes, gear drives and in steel-making equipment. They feature a special outer ring-guided, one-piece machined brass cage that gives higher strength and rigidity under vibrating conditions, plus the additional qualities of improved wear-life and resistance to corrosion.

The one-piece VS-Series brass cage ensures accurate guidance of the rollers via special cage pocket profiling, reducing harmful skewing of the rollers to a minimum. In addition large cage pocket corners relieve stress concentrations on the cage. Combined, these features reduce thermal effects within the bearings and help minimise resonance from induced vibrations.

The cage pocket design also improves grease or oil flow within the cage pockets, and the resulting improved dispersion of lubricant delivers the additional benefit of dampening noise.

The EMM-VS Series design is completed by a special crowning of the bearing rollers; this eliminates stress concentrations at the roller ends, helping the bearings to accommodate heavy loads and provide longer operating life. The same feature also enables the bearings to cope with misalignment between shaft and housings, effectively addressing another key area where damaging stress concentrations may occur.