Spindle Bearing of Lathe – Adjustment of Radial Clearance and Axial Clearance

When the lathe is cutting, because the radial clearance of the main bearing is too large, the front bearing clearance is mainly adjusted when adjusting the radial clearance of the spindle bearing. Taking the C620-1 lathe as an example, when the front bearing of the lathe spindle adopts a rolling bearing, the adjustment method for the radial clearance of the spindle bearing is as follows: loosen the supporting screw of the front nut, turn the front nut to the right to make the inner ring of the tapered bearing move along the axis, and then conduct a trial run. If the lathe spindle does not overheat at the highest speed. Under the condition that the supporting screw has no sense of blocking, the spindle can be turned by hand to tighten.

When the front bearing of the main shaft adopts sliding bearing, taking the C620 lathe as an example, the adjustment method of the radial clearance of the main shaft bearing of the lathe is as follows: loosen the jacking screw, rotate the front nut moderately in the constant ring, make the bimetallic bearing move axially, and keep the clearance between the main shaft of the lathe and the bearing between 0.02 and 0.03mm. After adjustment, the lathe needs a trial run. If there is no abnormal operation, the jacking screws can be tightened.

After the above adjustment, control the radial clearance of the lathe spindle bearing within 0.006 to 0.01mm. Inspection steps are also required. Use a dial indicator to measure the radial runout of the spindle centering shaft diameter. If the radial clearance of the lathe spindle bearing is too large, adjust the clearance of the spindle rear bearing and the spindle front bearing.