Balls become free from the ball slide due to broken plastic ball re-circulation parts.
Possible Causes Ball re-circulation disabled by abnormal wear caused by lubrication failure and intruded particles (Clogged ball re-circulation path) In a case of butting rail specification, a ball re-circulation part collided with the rail at the rail butting position because of excessive misalignment of rails in lateral and vertical directions Feed sped exceeded the permissible speed Countermeasures Review the lubricant and lubrication system Improve sealing function Improve butting accuracy (Lateral and vertical aligning accuracy at butting position) Review the feed speed. Focus at linear guide with high speed end capPart: End cap of Ball Slider
Symptom: Balls are free
Cause: End cap is damaged by excessive misalignment at the butting position of two rails. Ball slide operated at high speed in excess of permissible feed speed
Source: NSK