There are many main shafts in the grinding workpiece, causing the grinding wheel and the workpiece to swim in high-speed rotation, making the spindle shift, there will be corrugated and vibration in the milling workfoil, so that the main shaft itselfThe dynamic balance is in a situation where the front end bearing of the spindle is in the front side, and the sealing is not rusted, which also replaces the bearing, which is balanced from the new movement, which can fix the spindle.*** Terminal is that the spindle itself is not rigid. There is no quenching when making a casing, which directly leads to an abnormal sound in subsequent use. This situation can only replace the new intensive spindle.