Objective
This spindle which is running on VMC at leading automobile component manufacturer. This spindle was heavily damaged due to accident on the machine. We found cracks developed at spindle nose which was penetrated for 20 mm from the face of the spindle.
General observations before dismantling of spindle
• Bearings used : HCS 71914CTP4SUL: 04 nos B 7011 E 2RSD TP4SUL: 01 no
• Max speed : 10000 rpm.
• Lubrication : Grease packed.
• Axial play : Rigid
• Radial Play : Rigid
• Quill bore run out : Not measurable due to heavy damage
We found that spindle nose BT 40 was heavily damaged.
Activities carried out to recondition the spindle
Results achieved after assembly of spindle
We rebuilt the spindle by machining BT 40 taper and converted it to cylindrical bore. We produced insert with BT 40 taper and fitted it on the shaft by ensuring heavy interference. Find below the photographs of remanufactured spindle after grinding.
Quill bore run out : 2 micron
Axial play : Nil
Radial play : Nil
Run out on test mandrel of 200 mm in length : 10 micron
