Why Do Ball Screws Fail?
There are several reasons why ball screws fail, such as:
- Lack of lubrication: The lack of proper or sufficient lubrication is a leading cause of ball screw failure. To withstand high speeds, loads, and temperatures, ball screws require high-performance lithium complex grease or oil. Without it, ball screws can wear prematurely and fail.
- Dirty environment: A dirty environment can also wreak havoc on ball screws. Because linear guide rails and ball screws are precision equipment driven at high velocities, they require a very low amount of friction, but dirt will contribute more friction. Ensure proper cleaning schedules and protect the ball screws from dirt wherever possible.
- Misalignment: Ball screw misalignment can cause excessive noise, binding, extensive wear, and sometimes, snap (break) the ball screw unit itself. Some ball screws have self-aligning designs, allowing them to accommodate a higher level of mounting surface errors without sacrificing smooth motion. A ball screw repair expert can help you realign your specific ball screw properly.
- Excessive speeds: If a ball screw exceeds its top recommended speed, it can produce excess vibration and damage the screw or support bearings. The strain can result in gradual, premature failure or immediate failure. We recommend operating your ball screw assembly at or below the maximum speed.
How to Know When Ball Screw Repair Is Needed
To help you determine when your ball screw needs repairing, here are the most common warning signs:
- Surface deterioration: Severe or nonuniform wear on any of the ball screw components could be a sign of misalignment or improper lubrication. Other types of surface distress include pitting and corrosion.
- Excessive vibration (harmonics): Excess vibration could be a sign of misalignment that should be taken care of as soon as possible.
- Variation of positioning: This is often another indicator of wear to your ball screw.
- Discoloration: Heat discoloration can result from the ball screw operating at higher speeds than it should or consuming more power than is normal.
- Excessive power consumption: If the ball screw is not properly lubricated and encounters too much friction, the actuator must work harder and consume more energy. This added stress can lead to premature failure if not addressed early.
If your ball screw is exhibiting any of these warning signs, reach out to Rockford Ball Screw and we'll get it fixed.