Heald H120 Shaft Manufacture
Heald / Gamfior H120, 120,000 RPM, air/oil lubrication, stator drive
Our customer attempted to rebuild this high speed grinding spindle themselves but unfortunately it failed very soon after. After this experience, they decided to cut their losses and send us the spindle for rebuild. When the spindle arrived it had already been partially disassembled.
Our initial inspection revealed that the bearings & spacers were missing and that the field (stator) was not securely mounted in the housing. We also observed that the quill pilot & face were in extremely bad condition, and that the front nut & shaft rotor were damaged as well. Our dimensional inspection showed that the ID of both the front and rear housings were oversized by nearly double ISO. This rear housing deviation also contributed in part to a very loose slide fit for the rear ball cage.
Our rebuild of this spindle included manufacturing a new shaft & front nut, as well as new front & rear bearing spacers. We also had to grind, chrome plate & finish grind the ID of the front & rear housings and the OD of the ball cage bushing. We then proceeded to rebuild the spindle with all new ceramic bearings, o-rings, gaskets and assembly screws. After final assembly, our break-in, test run and outgoing QC process showed good balance, vibration and thermal values, with outgoing pilot & face runout of 1µ.