A certain level of noise will always be present in a ball screw assembly. Most engineers expect this when choosing a ball screw for their application. As long as the assembly is performing well, additional noise is no need for concern.
However, if the performance of the ball screw assembly begins to slip, an increase in noise could be a symptom of the larger problem. Diagnosing what is happening in your ball screw assembly is crucial in bringing the application back to top performance.
What causes ball screw noise?
The noise from ball screws comes from their mechanical design, in which ball bearings are internally rotated between the screw shaft and ball nut. Ball screw assemblies with a high RPM, high load, or high lead will often be the noisiest. Ball screw assemblies with a certain level of allowed backlash will typically be noisier than preloaded ball screw assemblies as well.
Most of the time, this added noise is not a problem. But combined with performance issues, it could be a signal of a problem within the ball screw assembly.
When is excessive ball screw noise a problem?
Excessive ball screw noise is a problem when it is paired with additional performance issues. Additional noise could be a signal a myriad of problems, including:
- Excessive backlash in the assembly
- Undersized or oversized ball bearings
- Debris within the ball nut assembly
- A damaged ball screw, ball nut, or ball bearings
- Improper or uneven load distribution on a ball screw
- And more
It is important to note, however, that excessive noise alone does not signify that one of these situations is at play in your ball screw assembly. But, if noise has increased and additional problems have begun to emerge, it may be time to take a closer look.
Although uncommon, certain medical applications do require a quiet ball screw assembly. For example, The PST Group worked with a client to manufacture an assembly used for lifting tables in patient rooms. This assembly needed to be quiet, as any excessive noise with equipment in a hospital could cause alarm or unease for a patient. To solve this problem, we recommended a preloaded ball nut with uniform coating to reduce the ball screw noise.
When should you be concerned about increased ball screw noise?
A certain level of noise should be expected from any ball screw assembly. Unless your ball screw assembly is operating in a situation where maintaining a low amount of noise is paramount to the success of the assembly, your focus in maintaining the ball screw assembly should be on the performance of your assembly, not on the noise that is being produced.
While ball screw noise is subjective, if a low noise level is required, the experts at PST Group can help. We work with customers directly to identify what level of noise is excessive, then cater the design and manufacturing process to create a ball screw assembly to meet those needs. If performance is also a concern, we can help diagnose the problem and suggest a proper solution.