The new MPAX brass cage from Schaeffler is a rib-guided, single-piece solid brass cage. It has a higher load carrying capacity for radial centrifugal forces (higher radial rigidity) than its predecessors and is also suitable for very high speed applications. In terms of the rail sector, cylindrical rolling bearings are particularly well suited to final drive gearboxes. Over time, the company expects the MPAX brass cage to gradually replace the previous cage types.
Schaeffler has improved the overall cage design by reinforcing the side edges, optimising side edge thickness and optimising the pocket corner radius position, resulting in reduced maximum stress on the pocket corner radii. Fatigue effects occur only when very large forces are applied. The cage is always rib-guided on one ring and the rollers can be removed.
In addition, the company has developed a new ceramic insulation coating for rolling bearings (including cylindrical rolling bearings) with outside diameters from 70mm to 800mm. Applied to the outer ring, the new Insutect A J20G coating is a cost effective solution for preventing damage to bearings due to the passage of electrical current. The ceramic coating, which is approximately 700µm thick, offers high capacitive resistance, high wear resistance and a disruptive (dieletric) strength of up to 5,000V DC. The coating helps prolong the life of lubricating grease and is suitable for bearings that operate in dry or damp conditions.
The coating is applied using the plasma spray method and sealed. Coating variants are available from Schaeffler to suit a range of different bearing applications such as rail, wind turbines or industrial three-phase electric motors.