Step 1: Remove the spindle, polish the spindle journal, improve the surface roughness of the spindle, and make the spindle roughness of the CNC cylindrical grinder reach Ra0.05um. Then carry out fine grinding to make the roughness reach Ra0.05um or more.

Step 2: The lubricating oil of the static pressure oil tank is 30% 20# mechanical oil and 70% kerosene, add the opening pressure of the oil tank, use the relief valve to adjust the pressure to about 1.5Mpa, and use the feedback throttle to enter the oil cavity into the oil chamber. The oil pressure is adjusted to about 1.0-0.6Mpa. When the lubricating oil enters the bearing oil cavity, check whether there is a phenomenon of light on one side and sinking on the other side after locking. The spindle of the grinding wheel should float in the middle of the bearing.

Step 3: Before repairing, use a dial indicator to detect the radial runout and axial movement of the main shaft to check the degree of wear of the main shaft and whether there are cracks.

Step 4: Pull out the eight oil cavities on the front and rear bearings above the bearing holes. After cleaning the 0.5 mm throttling orifice with gasoline, scrub the bearing diameter and install it into the spindle. The gap between the shaft shoulder and the end face is controlled by adjusting the thickness of the washer with grinding.