How Do Ball Screws And Ball Nuts Work?

Have you ever wondered about how ball screws function? While these screws perform fairly important tasks, they aren’t as complex as you might think.

When a ball screw is assembled, a screw and a nut are connected to each other. Each one has complimentary helical grooves. There are also balls that roll in between the grooves. This is the only contact that occurs between the screw and the nut.

lead-scewThese devices also use a deflector. When either the screw or the nut is rotated, the deflector pushes the balls into the nut’s ball return system. From there, they travel through the return system, moving to the opposite end of the nut. After that, they exist from the return system and enter the space between the ball and nut. The balls continually recirculate in a closed environment.


The nut and screw have a direct impact on each other. If a ball nut circuit has a limit number of threads, both the ball nut and the ball screw will wear out more rapidly than they would otherwise. If there is an issue with the ball screw, the nut may be the source of the problem.

If a machine moves at a very high speed, it may use some kind of tangential system for ball returns. That way, the balls can slow smoothly even though a limited amount of space is available to them. This type of design is also used for devices that handle high loads.

screw2Other types of machines have different requirements. Even a tangential system may not be enough for a device that reaches extremely high speeds. Some of them may require a rotating ball nut, or a longer shaft length. Engineers have to work to find the best design for each machine.

The ball nut and screw system is frequently used to move control surfaces in large devices such as aircraft and missiles. It is also used in power steering for automobiles. However, their most common application is in various types of industrial machines. Many machines rely on these kinds of systems to complete various tasks.

Ball screws and ball nuts need a great deal of care to keep functioning. If they are exposed to dirt, dust, or other types of abrasive materials, they may not be able to function properly. Even a small piece of dust could keep a ball from moving on the right path.

Because of this, any device that uses this system will require regular maintenance. If there is a problem with a device that uses ball nuts or screws, a professional will have to look at it and diagnose the problem.

Thankfully, ball nuts and screws can be replaced as needed. As long as people care for machines that use a screw and nut system, the machines should be able to keep functioning properly. Rotating ball nut design is an essential component of modern engineering. Many devices rely on this sort of system.