Recirculating Balls

Recirculating balls are hardened steel or ceramic spheres that travel through a closed-loop circuit within ball screw nuts or rack & pinion assemblies. They roll between the screw/rack and nut/pinion surfaces, distributing load evenly across multiple contact points to achieve smooth linear motion with efficiencies exceeding 90%. The balls exit the load zone, travel through return tubes or deflectors, and re-enter the circuit continuously during operation.

The balls roll along helical grooves in ball screws or linear tracks in rack & pinion systems, carrying axial loads while minimizing sliding friction. As the screw rotates or pinion moves, balls circulate through load-bearing zones and return passages, creating a continuous rolling motion that converts rotational force into precise linear displacement with high mechanical efficiency.