How to deal with accuracy error after using the vertical machining center for a period?

Time: 2016-08-09

We all notice that after a period of running of machining center, there will be tolerance on the accuracy. We can analyze the accuracy tolerance from the following aspects.

1. The tolerace on work piece. This is mainly because of the bad adjustment on the feeding state on each axis. Or maybe after abrasion, there is change on the transmission chains( e.g. axial clearance, pitch error change, axial movement etc.) And it can be re- adjusted or solved by changing the backlash compensation data. If there is alarming as the dynamic error is too big, you can check the following: the speed of the servo motor is too high or not; Position detecting unit is normal or not; The contact of position feedback connector is normal or not; And output latch of the relative analog quantity and GIAN SPD is normal or not; And the relative servo units are normal.

2. The overstroke on machine results in the bad accuracy. This may because of the the time for speeding up and slowing down is too short, which can be sloved by prolonging the time of speed change. Or the connecting and the rigidity betwee servo motor and ball screw is not good, which can be solved by shortening the accumulation of position loop. 

3. The roundness go out of tolerance when two axes linkage. 1) Axial deformation on circle: This mainly because the machine is not adjusted well. As the position accuracy is not good or the Screw gap compensation is wrong, the roundness error will happen 2) Oblique ellipse error: Firstly check the deviation value of each axis, if it is too big, then solve it by adjusting the accumulation of position loop. Then check and see if the the interface board of rotary actuator or inductosyn was well adjusted, and then check and see if the Mechanical transmission pair clearance is too big or not, and backlash compensation is correct or not. After clearing problems through these aspects, the accuracy error can be solved.

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