Damage Condition

Damage on the tongue of ball return tube (ball pick up finger).

Possible Causes Rotational speed exceeded the permissible rotational speed (d•N) Countermeasures Use of a ball return tube that meets the actual d•N value Change to end-deflectors ball screws enabling higher speeds
Breakage of Ball Recirculation Parts

Part: Ball return tube
Symptom: Damage on the tongue of ball return tube
Cause: High-speed operation exceeded the permissible rotational speed (d•N)

Source: NSK