Since ball screws often work in environments full of dirt and debris, manufacturers can take multiple precautions to keep out contamination and preserve the life of the screw.

Sometimes screws are coated with a thin dense chrome, black oxide or nickel-plated finish to help preserve ball screw life. Some manufacturers prefer to equip bellows boots that expand and contract like an accordion as the nut moves along to keep it covered from contamination.  Bellows boots can be supplied in numerous materials so that they may be applied in even the most extreme applications.

Another form of protection manufacturers uses are wipers. Nut wipers can be felted or plastic wipers that brush the nut free of any dirt or other contaminants and keep contaminants from entering the ball nut.

There’s so much variance between different ball screw applications that there is no definitive answer for the amount of lubrication needed for each ball screw. However, considering factors such as frequency of use, temperature and viscosity are essential considerations for lubrication options. While a light oil or grease is suitable for most applications, the use of any lubricant containing molydisulfide or graphite should be avoided. A good rule of thumb is to always apply enough lubrication to maintain a thin film of lubricant between the nut and the screw.