During the machining process, the vibration of the lathe is easy to cause the surface of the workpiece to have a shock
pattern, resulting in high rework rate and scrap rate. The reasons for the vibration of the lathe include the machine tool,
the workpiece to be processed, and the tool. The following briefly introduces the vibration knife during the lathe
processing. Reason and how to troubleshoot.
1. Workpiece structure that is easy to generate a vibrating knife
(1) External turning of slender shafts; the distance between the general cutting points and the nip point is easy to vibrate
if the length-to-diameter ratio exceeds 3, and the process can be considered;
(2) External turning of thin-walled parts;
(3) Turning of box-shaped parts;
(4) Superhard material cutting.
2,Reasons for the tool
(1) Forming turning using a forming tool;
(2) The angle of the tool, especially the lead angle, the back angle, the front angle etc;
(3) the sharpness of the tool;
(4) Whether the radius of the tool nose arc is too large;
(5) Whether the cutting parameter is suitable.
3. Reasons for machine tool
(1) The live top is too long
(2) The bearing has been damaged and continues to cut
4, How to eliminate the knife problem in the tool
First check the rigidity of the cutter itself, is it not clamped? Is it stretched out too long? Is the gasket uneven? Then
check if the turning tool is worn? Is the corner of the tool or the edge of the wiper too wide? Is the back angle of the
turning tool too small? Look at the 90 degree knife or 45 degrees you are using now, try it out.
In addition, the tool (feed rate) is too small, it may also be a cause of trembling, can be slightly adjusted to increase
a little. Adjust the speed, single-cut depth, and feed rate to try to eliminate the resonance point
5. Check the reasons for the machine tool and the loading position
(1) Find out if your live top is too long and the bearing is not good. There is a flat rolling bearing combination inside.
It is really doubtful that you can use the dead top for replacement, pay attention to the butter lubrication of the center
hole.
(2) Find out the clamping condition of your tailstock. Under the clamping condition, it is not the left and right, the upper
and lower sides are not the same as the machine tool spindle.
(3) Tightening the large, medium and small trailers, especially the middle carriage.
(4) If it is the tailstock part of the machine tool, you can't check it temporarily (points 1 and 2, you need some benchwork
foundation), you can try to take the knife from the grip end to the tail. Anti-vehicle, can cut off the end of the force to the
maximum extent.
(5) If there is still a situation in step 4, it is necessary to look at the main shaft. Of course, if it is three catches, it is
necessary to check whether the spiral groove is damaged. Four catches are artificially self-supporting and do not need
to be checked.