Technical Blog

Ball Screws vs Lead Screws

Motion applications require effective linear motion transfer systems, such as ball screws and lead screws. In most instances, you can use either a ball screw or a lead screw in the same application, but which one will be most effective? And what are the differences?

We asked our engineering experts the most common differences between ball screws and lead screws to help you make the best choice for your application. 

Ball Screws vs Lead Screws: What are the differences?

Typically, in most applications you can use either a ball screw or a lead screw, but there are key differences between the two that will help you determine which is best to use.

Whilst a ball screw uses recirculating ball bearings to minimize friction and maximize efficiency, a lead screw depends on low coefficients of friction between sliding surfaces. Lead screws use helical (spiral shaped) threads and a nut, usually made of a polymer composite or bronze. Due to the rolling nature of ball screws, this eliminates the sliding friction that is usually associated with lead screws.

A ball screw design is much more complex compared to that of a lead screw. A ball screw requires hardened precision bearing surfaces and a ball re-circulation mechanism, whereas a lead screw is very compact and offers great design flexibility. They can also be made to self-lock for vertical applications and are usually quiet when properly applied.

Ball Screws vs Lead Screws: Which one to use for my Application?

Another main difference between a ball screw and lead screw lies within their use in an application.

Ball screws are generally better suited to applications that require smooth motion, efficiency, accuracy, precision and prolonged continuous or high-speed movement. Lead screws tend to be more suited to transfer applications where speed, accuracy, precision and rigidity are not as vital.

Ball screws tend to be used in industrial applications that require a higher load or life, whereas lead screws are used in smaller, lighter duty applications. Lead screws however are highly customisable with the ability to interchange leads, sizes, nut configurations quickly.

In addition to materials, assembly design, and accuracy, other important variables to consider include movement error, noise, maintenance, efficiency and longevity. Evaluating the load, accuracy, and lead for your application tends to help answer the question of whether a ball screw or a lead screw is better suited to your application.

Ball Screws & Lead Screws from Heason Technology

All of our ball screws and lead screws that we offer are from our supplier Thomson Linear. They are all well suited to linear motion applications.

Ball Screws

Ball screws are mechanical linear actuators that translate rotary motion to linear motion by using a recirculating ball mechanism between the screw shaft and the nut. A threaded shaft provides a helical channel for ball bearings which act as a precision screw. 

Ball screws can apply or withstand high thrust loads with minimum internal friction. They use ball bearings to eliminate friction between the nut and the screw and can offer a high level of efficiency, load capacity and positioning accuracy.

Ball screws from Heason Technology can be used in the most extreme environments, such as high-performance machine tools which have very high demands, and in very delicate and sensitive applications including medical devices.

Our ball screws are available in a full range of diameters, leads and ball nut configurations with pre-loaded or non-preloaded options. All of these are to industry standard and provide dependable accuracy and repeatability at a good price. 

Offering excellent reliability and reliable performance, our ball screws consistently perform the way they are expected to. The materials used are to the highest quality and are compatible with many applications ensuring a long life.

Advantages of Ball Screws

  • Highly efficient, requiring less torque – therefore smaller motor
  • Higher accuracy grades for greater positional accuracy
  • Lower friction – able to run at cooler temperatures
  • Available in rolled and ground types
  • Can be adjusted to increase/decrease preload
  • Need to be replaced less frequently
  • Available in screw diameters from 4mm to 80mm

Lead Screws

Lead screws, also known as a power screw, are used in motion control to translate turning or rotating movements into a linear motion. They are bars of metal with a thread, similar to a traditional screw. Lead screws rotate, causing the nut to move along the screw in a linear motion.

Lead screws from Heason offer a smooth and precise solution for linear motion requirements, as well as being cost-effective. They are accurate to 0.003in/ft and the PTFE coating process that our lead screws are exposed to means that they have less drag torque and will last longer.

Choose from plastic nut assemblies in either anti-backlash or super-nut designs which all use an internally lubricated acetal. This provides excellent lubricity and wear resistance weather additional lubrication is used or not.

We can provide assemblies with high axial stiffness, zero backlash and minimum drag torque to reduce motor requirements; using these products means your system will cost less, perform better and last longer, making them great value for money.

Heason also has bronze nuts available if you have a significantly higher load, providing the support needed for high capacity loads and a good PV performance.

Advantages of Lead Screws

  • Competitively priced
  • Self-locking – do not require a breaking system
  • Well suited to vertical applications
  • Flexible configuration
  • Less noisy compared to Ball Screws
  • Available in screw diameters as small as 6mm

Click for further information on any of our Ball Screws and Lead ScrewsIf you are still unsure on which screw to use within your application, please contact our sales team on +44 (0) 1403 792 300 or sales@heason.com

Jeff Johnson, Thomson Industries Screw Product Engineer, describes the differences between ball screws and lead screws:

 

 

 

 

 

Article published on: 15/08/2019