The Importance of Proper Lubrication for Acme Screws

by Christopher Nook

The coefficient of friction, wear life and resulting torque to drive acme screws and acme screw assemblies are highly controlled by the ability of the engineered plastic to supply sufficient lubrication to the nut and screw interface.

Proper lubrication is the key to continued performance and reliability of lead screw assemblies.

Prolong acme screw assembly reliability and life

Many factors have to be considered when designing and selecting a precision acme screw. Environment, operating load, accuracy and speed are all important factors to consider in the design decision. Unlike ball screws, acme lead screws with bronze or polymer nuts tend to have higher friction and more wear - making proper lubrication a vital part in performance and increased life.

Benefits of a proper lubrication

There are several main benefits of using proper lubrication, to include:

Sheer Stability
High Temperature Resistant
Corrosion Protection
Separation Resistant
Extreme Pressure Properties
Shelf Stable
Water Resistant

Extend life and longevity

Precision acme lead screws are manufactured from high quality materials with excellent dynamic properties. Because of the variable effects of friction, lubrication and cleanliness, a specific life cannot be predicted. Proper lubrication, regular maintenance, and operation within specified limits will extend the screw's life and longevity.

Lubrication intervals are determined by the application. It is required that screw assemblies are lubricated often enough to maintain a film of lubricant on the screw.

Importance of efficiency

Efficiency of precision acme screw assemblies range from 15% to 85%. These efficiencies are dependent upon the nut material, lubrication, lead and thread form.

Temperature precautions

With proper lubrication, acme screws with bronze nuts operate efficiently between 15°F and 350°F, and plastic nuts between 15°F and 175°F.

Proper lubrication must be provided to achieve satisfactory service life of your acme screws and acme screw assemblies. It is required that screw assemblies are lubricated often enough to maintain a film of lubricant on the screw.

Lack of lubrication

Lack of lubrication can result in the reduction of the life and performance of the acme screws and the entire machine. Often times, a lack of lubrication can cause erratic drag torques and unpredictable wear.

Specifying a lubricant

Even self-lubricated nuts can benefit from using a light grease and can also reduce heat in these units.

Good and consistent lubrication has long-term benefits and is more important to a lucrative to an application than whether the screw was cut or rolled. When maximum performance is required in the most demanding applications, using the proper lubricant and the proper amount can help you reach maximum productivity.

There are certain applications which require more/less lubrication, external/internal lubrication and more/less maintenance. When lubricants are applied properly they can provide unique capabilities which may be difficult to obtain without the use of any lubricant.