CNC machining is a processing method for
precision parts processing. Therefore, the requirements for CNC machining
products are extremely high. Products with low precision are also required to
be rebuilt or directly scrapped. For CNC machining manufacturers, it is very
scary. Xiaobian told everyone about the reasons and solutions for the
inaccuracy of CNC machining.
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| cnc machining parts |
1. The workpiece size is accurate and the
surface finish is poor.
The cause of the failure: the tool tip is
damaged, not sharp; the machine tool generates resonance, the placement is not
stable; the machine tool has crawling phenomenon; the processing technology is
not good.
Solution: If the tool is not sharp after
being worn or damaged, re-grind the knife or choose a better tool to re-align
the tool; the machine will generate resonance or place it is not stable, adjust
the level, lay the foundation, and fix it smoothly; the reason for the
mechanical creep is drag The guide rail of the plate is very worn, the screw of
the lead screw is worn or loose, and the machine should pay attention to
maintenance. After the work, the wire should be cleaned and the lubricant
should be added in time to reduce the friction. The coolant suitable for the
workpiece processing can be selected to meet the processing requirements of
other processes. In the case, try to use a higher spindle speed.
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| cnc machining parts |
2. The workpiece produces a taper size
The cause of the fault: the level of the
machine tool is not adjusted well, one high and one low, the placement is not
stable; when turning the long axis, the contribution material is relatively
hard, the tool eats the knife deeper, causing the knife phenomenon; the
tailstock thimble is not concentric with the main shaft.
Solution: Use the level to adjust the level
of the machine, lay a solid foundation, fix the machine to improve its
toughness; choose a reasonable process and appropriate cutting feed to avoid
the tool force to make the knife; adjust the tailstock.
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| cnc machining parts |
4. The processing arc effect is not ideal,
the size is not in place
The cause of the fault: the overlap of the
vibration frequency causes resonance; the processing technology; the parameter
setting is unreasonable, the feed speed is too large, the arc machining is out
of step; the looseness caused by the screw gap is large or the screw is too
tight; abrasion.
Solution: Find the part that produces
resonance, change its frequency, avoid resonance; consider the processing
technology of the workpiece material, and make the program reasonably; for
stepper motor, the processing rate F can't be set too large; whether the
machine is installed firmly, placed smoothly, drag Whether the board is too
tight after wear, the gap is increased or the tool holder is loose; etc.;
replace the timing belt.
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| cnc machining parts |
5. There is a change in the processing of
one part of the workpiece, and the dimensions of other processes are accurate.
Fault reason: Whether the parameters of the
program block program are reasonable, whether it is within the predetermined
track, and whether the programming format meets the requirements of the manual.
Solution: If there is a chaotic tooth in
the thread block, if the pitch is wrong, it immediately associates with the
peripheral configuration (encoder) of the cnc machining thread and the objective
factor of the function.
