Blohm SKF Grinder Spindle Repair

This Blohm SKF Grinding spindle we repaired is grease lubricated and belt driven.  This spindle is used by one of our customers to grind parts for turbines in the aerospace industry.

CHALLENGE

When this Blohm SKF Grinder spindle arrived at Northland Tool and Electronics we noted that there was measurable  endplay incoming.  Upon starting to break down the spindle, we noted that the front of the spindle was heavily contaminated.  This contamination made it through into the front bearings due to the seal surface of the front nut being worn.  The critical dimensions were then measured and we found a couple issues.  First, the front bearing housing was severely egged. (+1/+13µ a 12µ egg).  Second, the front OD tooling taper had significant runout when measured as a bare shaft (26µ).  No other dimensional deviations were noted for this repair.

SOLUTION

The following actions were performed on this Blohm SKF Grinder spindle:

• Clean, inspect overall dimensions
• Replace bearings, o-rings, and assembly screws
• Grind, chrome plate, and finish grind (GPG) the nut seal surface
• GPG front 110mm housing
• Kiss grind front OD tooling taper

RESULT

After reassembly of all components, adjusting bearing preload, and undergoing break-in and testing procedures, this spindle passed our final quality inspection before being returned to our customer with a 1-year warranty.