You may have heard these two terms being thrown around in your linear actuator research, but do you really know exactly what each one is, the differences and the advantages of each? Ball screws and lead screws are used for different applications, they are oftentimes not interchangeable and have alternate advantages and disadvantages.
If you compare a ball screw and lead screw design yourself, the first thing you might notice is that they are designed to carry loads differently. The way ball screws move a load is through recirculating ball bearings to maximize efficiency and minimize friction. A lead screw relies on the amount of friction between surfaces to be low compared to the amount of pressure being applied. That means that a lead screw just doesn't have the same capability to be as efficient as a ball screw.
That's not the only difference between ball screws and lead screws. They also provide linear actuators with better performance or faster speeds, depending on which design model you choose. Here's a rundown of the advantages and disadvantages of each option.
Of the two options, ball screws are the more expensive route. Some individuals choose ball screws because they have faster rates of speed with continuous duty cycles and are able to carry higher loads than lead screws. Sometimes, there are applications where the ball screw is the required object and there's no choice in the matter. If you are in factory automation, you probably know that there is a heavy reliance on ball screws. They are reliable and easily integrated into a project.
The main drawback to the ball screw is the complex design, which also means it will be more difficult to replace or troubleshoot. They need a hardened precision bearing surface and ball recirculation mechanisms.
The cheaper of the two, lead screw actuators are mainly used when an industry needs a cost-effective solution. An industry may go for the lead screw when they need a solution that is quiet, flexible, corrosion-resistant, and has some self-locking capabilities. The drawback is that they are not as fast and cannot carry the same loads as the ball screw.
While this is just a primer for ball screws and lead screws, there are many different applications that use each one, so it will take some time and some research to discover which design will work best for your application.