Common defects and solutions of centerless grinder

Centerless grinder is a kind of grinder which does not need to use the axis of workpiece to carry out grinding. It is composed of grinding wheel, adjusting wheel and workpiece bracket. The common grinding defects of centerless grinder and their elimination methods are summarized as follows:

1. The reason of non-round parts

(1) the guide wheel has not been rounded. 

(2) the number of times of grinding is less or the ellipse degree of the last working procedure is too large .

(3) the grinding wheel is blunt .

(4) the amount of grinding is too large or the amount of cutting tool is too large.

The eliminating method

(1) repairing the guide wheel, waiting for the guide wheel to repair circle to stop (generally to stop without intermittent sound).

(2) increase grinding times properly.

(3) refinish the grinding wheel.

(4)Reduce grinding and heavy tool speed.

2.parts have edge edge (polygon) causes.

(1) the center height of the part is not high enough.

(2) the axial thrust of the part is too large to make the part press the retaining pin tightly and can not rotate evenly.

(3) unbalance of grinding wheel.

(4) the part center is too high.

The eliminating method

(1)precisely advancing the center degree of the part. 

(2) reduces the inclination angle of the guide wheel of the grinder to 0.5 ° or 0.25 ° . If the block can not be resolved, it is necessary to check the balance of the fulcrum.

(3) the balance grinding wheel (4-RRB- reduces the center height of the part properly.

 3.The reason of the vibration marks on the surface of the part (i. e. the fish-colored and straight white lines on the surface of the part.

(1)the vibration of the machine tool caused by the unbalance surface of the grinding wheel. 

(2)the movement of the part due to the advance of the center of the part. 

(3)the grinding wheel is blunted or the surface of the grinding wheel is repaired by too much light. 

(4)the method of eliminating the rotating speed of the guide wheel is too fast. 

The eliminating method

(1)carefully balance the grinding wheel. 

(2)appropriately reduce the center of the part. 

(3)the grinding wheel or appropriately increase the dressing speed of the grinding wheel. 

(4)appropriately reduce the guiding speed.

4. The taper of the part occurs

(1)the front part of the part is small because of too much lower guide bar of the guide wheel, or because of the inclined plane of the guide wheel of the guide plate.

(2)the back part is small because of the inclined surface of the back guide plate and the GUIDE WHEEL OF THE GUIDE Wheel of the guide wheel or because of the low guide bar of the Back Guide Plate.

(3)the taper occurs at the front or back part of the part because of the following reasons. 1. The grinding wheel is not corrected by dressing, 2. wheel and guide wheel surface has been worn to .

The eliminating method

(1)the appropriate move and adjust guide plate guide plate and guide wheel bus parallel .

(2) after the guide plate guide surface and guide wheel bus parallel to adjust, and on a line. 1 according to the direction of the taper of the part, adjust the angle of the grinding wheel in the modification of the grinding wheel 2 grinding wheel and guide wheel.