Gilman 245/TWG Spindle Repair

This spindle came to us as an expedited repair. It came from a machine that feeds several other departments in their facility where each hour of downtime costs them thousands of dollars. We completed this repair for them in record time, even with grinding performed. We can accomplish this because we do all of our grinding work here in our grinding department that is set up specifically for reworking spindle parts. Most of our competitors rely on outside vendors for their grinding and that leaves them at the mercy of their vendors. We have much better control of our quality and lead times because of this.

CHALLENGE

Our customer sent in this Gilman 245/TWG spindle and indicated that they were experiencing bearing noise, excessive runout, and a defective proximity clamp sensor.  Upon disassembly and inspection, we found that the drawbar actuator was leaking and preventing drawbar actuation.  The front bearings were contaminated and the grease was partially washed out.  The critical dimensions (bearing journals, taper, housing, etc.) were measured, and we found that the HSK 50 taper and face had 8-10 microns of runout.  We also noted that the rear nut groove was slightly damaged and the encoder sensor wires were broken off flush at the sensor making it not testable.  All other sensors tested good.

SOLUTION

The following actions were performed on this Gilman 245/TWG spindle:

• Clean, inspect overall dimensions
• Replace bearings, o-rings, bellevilles, drawbar seal, snap ring and drawbar actuator
• Grind, chrome plate, and finish grind the HSK 50 taper
• Machine damaged drive dog and rear nut groove

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.