The maximum vertical machining center processing property is consistent batch workpiece size must be very high, we know that the original traditional machining workpiece from a procedure node to another procedure, have to undergo the process of clamping again, this process relies on manual operation is difficult to achieve the processing size of every component completely consistent. Of course, this does not mean that the ultra poor, as long as the workpiece tolerance zones are qualified, this may in some workpiece size difference appeared, some artifacts in the difference, but some may wander in workpiece, keep the workpiece size consistency is difficult to be guaranteed.
So at this stage of the vertical machining center use rate is the highest in small and medium-sized processing enterprises, of course, the price of vertical machining center CNC machine tools is the highest, he has high processing efficiency, high processing precision, from these two aspects will be solved to maintain the workpiece size consistency problem. Of course, if the numerical control parameters are not set or the operation is improper, the vertical machining center will also appear the phenomenon of super poor processing in the actual processing. This paper gives a brief introduction to the causes and solutions of the common processing overrun in vertical machining centers.
The machining precision of vertical machining center deviation mainly as follows: the inner hole surface roughness value is high, the hinge hole and a hinge Buyuan hole position tolerance and inner surface of the hole center line edge surface, obviously after reaming hole is not straight, narrow aperture, aperture.
One, the accuracy of the hole position accuracy of the hinged hole
The cause is probably due to the wear of the guide sleeve of the vertical machining center, too far from the bottom end of the guide sleeve, the short length of the guide sleeve, the poor accuracy and the looseness of the spindle bearing.
Solution: vertical machining center reaming Shiru position accuracy of hole deviation can make the following maintenance guide sleeve, the guide sleeve extended regular replacement according to the common problems, improve the accuracy, and the guide sleeve with reamer clearance timely maintenance of machine tools, spindle bearing clearance adjustment.
Two. The surface roughness of the inner hole is high
Cause: vertical machining center hole surface roughness is high, many reasons, may be due to high cutting speed, cutting fluid, improper reamer main angle is too large, too large margin, reaming Reaming allowance is not uniform or too small, not sharp blade, cutting blade with hinge the width and reaming when the chip is not smooth, reamer excessive wear, there may be a reason for the selection of tool and material mismatch.
Solution: because of many reasons for high surface roughness, so to solve more complex, from the following aspects: to reduce the cutting speed, according to the material selection of cutting fluid, decreasing reaming Reaming allowance, improve accuracy and quality before the bottom position or increase reaming allowance, increase the groove space or the reamer with cutting edge inclination, the chip successfully, replacement of reamer, regularly select proper cutting tools, such as processing steel parts to choose suitable tool steel processing and other measures.
Three. The enlargement of the processing aperture
Cause: the reason of vertical machining center processing aperture gradually increase possible: reamer diameter size design value is too large or hinge edge burr, cutting speed, high feed rate or improper machining allowance is too large, the main angle is too large, the reamer reamer reamer blade bending, pasted bue, blade when the hinge blade swing error, cutting fluid selection is not appropriate, there may be a CNC machine itself, the shaft bending or bearing too loose or damaged, there may appear afore-mentioned problems.
Solution: have the following countermeasures according to the actual inspection of the situation: reduced appropriately according to the specific situation, reduce the reamer od cutting speed, adjust the feed rate or reduce machining allowance, reduce the main angle, bending straightening or scrap can not be used to select the cooling performance of reamer, cutting fluid, better adjust or replace the spindle bearings. Or replace the whole spindle.
Four, the inner hole of Buyuan hinge
Causes: processing the hole Buyuan roundness, not enough is mainly due to the following factors: the reamer is too long, lack of rigidity, vibration reaming, reamer main angle is too small, reaming allowance is small, the inner hole surface of cross hole and gap, especially the pore surface pores, trachoma, and may be loosening machine spindle bearing.
Solution measures: from the following aspects: reaming should be rigidly connected, and qualified reamers should be selected to control the tolerance of holes in pre processing operations, to adopt unequal pitch reamers, to select qualified blanks, and to adjust machine tool spindle clearance in time.
Five. The center line of the rear hole of the reaming hole is not straight
Cause: processing Kong Shi vertical machining center, the center line is not straight possible reasons may include: drilling hole, especially the pore size is small, the reamer is less rigid, cannot correct the original bending, reamer main angle is too large, poor guidance, easy to deviate from the direction, the reamer in reaming cutting part of the inverted cone is too large, intermittent clearance in the hole reamer displacement etc..
Solutions: increase reaming or boring process correction holes, reduce the main deflection angle, adjust the appropriate reamers, replace the reamers with guiding parts or lengthening cutting parts, and pay attention to the correct operation.
