A ball screw is an apparatus made up of a screw, a rotating nut, and the balls that help the nut to move along the screw smoothly. Ball screws work by converting rotational motion to linear motion. A ball screw preload eliminates the space (also known as clearance or backlash) between the ball screw and the ball nut. There are a few reasons that preload is beneficial. Here is what to know about ball screw preload and its benefits.
Preload Reduces Axial Play
One of the major functions of ball screw preload is the reduction of axial play, or backlash. Backlash is when the nut reverses its direction and moves along the screw without either being actively turned. This phenomenon is common in ball screws because the balls in the design create more clearance between the screw and the nut than in other types of screws. Preload compensates for this backlash by exerting a certain amount of opposite force to counteract the screw’s backlash.
Preload Increases Rigidity
When preload is added to a ball screw, the screw becomes more rigid. This is because a preload places a load between the screw and nut, causing the whole ball screw to become more rigid. In certain situations, such as when a machine needs to be able to withstand high impact, a highly rigid screw will be necessary.
Make Sure To Choose the Correct Preload
Depending on what type of machine you will be using your ball screw in, you will need a different amount of preload. The more preload is applied, the more rigid the ball screw will become, so take into consideration how rigid a screw your project requires. Applying too much preload in your ball screw can result in faster wear and a shorter lifespan for the screw, which makes it very important to choose the correct amount for your needs.
Preload Can Be Added To Existing Screws
Now that you’ve learned what to know about ball screw preload, you will be able to determine whether your machine requires a screw with preload and what factors to consider if it does. The good news is that if you find your ball screw preload in need of adjustment, it is possible to adjust the preload percentage of a screw. Wedin International, Inc. offers ball screw refurbishment services for these situations and others that may arise. We will fix the issue and send your ball screw back to you, good as new and ready to be used.