Can planet roller screw replace ball screw ?

Planetary roller screws allow for higher static and dynamic loads compared to ball screws. Its function is to replace the ball with a threaded roller to ensure that the load is distributed over a greater number of contact points.

What is the difference between planetary roller screw and ball screw?

The main difference between a planetary roller screw and a ball screw is that the load transfer unit uses a threaded roller instead of a ball. The main advantage is that the design of more contact points and thread angles makes its load equal to that of larger diameter ball screws.

● Speed and accelerationPlanetary roller screws allow for higher static and dynamic loads compared to ball screws. Its function is to replace the ball with a threaded roller to ensure that the load is distributed over a greater number of contact points.

● Load and lifeRoller screw can provide higher speed and greater acceleration ARV standard planetary screw adopts non-circulating design, which means that the mechanical performance can reach twice the speed of the ball screw. Acceleration up to 3g.

● Stiffness and strengthThe amount of contact points and the geometry of the contact points give the planetary screw greater stiffness and impact resistance than the ball screw.

● Lead and pitchThe lead of the planetary roller screw can be designed to be smaller than the ball screw. The lead of the planetary screw (the length of linear movement per revolution) can be very small. Due to the limitation of multiple threads, ALM’s small-diameter ARV standard planetary roller screw series can usually achieve 1mm leads, and the lead screw lead can also be made into a decimal number, which can be more flexible to match customer requirements to drive direct connection, compared with ball screws, which is also an advantage. The selection and realization of leads do not require any geometric changes in the screw and nut, and the minimum lead of the ball screw is limited by the size of the ball that can match the thread, small leads for the ball screw means small ball and relatively small load.