Four point contact bearings are single-row bearings in which the balls contact both inner and outer ring raceways at four points - two on each ring. This unique contact geometry allows the bearing to support axial loads in both directions simultaneously, as well as moderate radial loads, within a very narrow axial envelope. Unlike paired angular contact bearings requiring two rows for bidirectional axial loading, the four point contact design achieves this in a single row - saving significant space in gearbox and slewing applications. The Gothic arch raceway profile that creates four-point contact is especially advantageous where alternating axial loads act in both directions without a defined predominant direction. Gearbox bevel and helical gear thrust stages, turntable and slewing ring sub-assemblies, and medical and robotic systems with reversing axial forces are natural applications. Four point contact bearings are available in standard and precision grades. Internal clearance adjustment is critical - the balls must contact all four contact points without excessive preload that would cause overheating and reduced service life. Cage material is typically brass for high-speed applications, or polyamide for moderate-speed, low-noise use. Open and sealed configurations are offered. Four point contact bearings are specified in gearbox designs requiring compact axial guidance in both thrust directions, robotic joint assemblies needing bidirectional axial support in minimum space, turntable and indexing table systems, and applications where weight and compactness are fundamental design requirements that prevent the use of paired angular contact alternatives.
