1. Poor surface finish of the workpiece

The cause of this phenomenon is mostly the damage of the tool tip and the lack of sharpness; the instability of the machine tool or the occurrence of resonance and crawling; the imperfect processing technology. You can change or sharpen the tool, and re-cut the tool; adjust the flat temperature of the machine; change the worn carriage rail and screw ball, add lubricating oil, choose the right cutting fluid; and use the highest possible spindle Speed to solve.

2. Workpiece taper size head phenomenon

This problem occurs because of the unstable placement of the machine tool; when turning the long shaft, the workpiece material is too hard, which causes the tool to eat a large amount of the tool, resulting in the tool making phenomenon; in addition, the tailstock thimble is not concentric with the spindle. Adopt the spirit level to adjust the level of the machine tool, and reliably fix it to improve its rigidity; it must be fair when choosing the cutting technology and feed rate, and it is better to show the knife; and adjust the machine tool tailstock, these methods can eliminate the taper size of the workpiece.

3. The size of the workpiece is large and small

The screw and bearing of the machine tool pallet working for a long time are worn; the long-term use of the tool holder makes the repeated positioning accuracy not allowed, which is the main evil that causes the workpiece size to be small during the period. If you encounter such a problem, you should first check the repeat positioning accuracy of the carriage. The method is to compile a fixed cycle program in the system, and then measure the dial against the bottom of the tool holder. If it is a screw or bearing problem, answer Adjust the screw clearance and replace the new bearing; then use the same method to check the repeated positioning accuracy of the tool holder and the accuracy of the workpiece after machining will lead to the starting point of the program; if there is no problem above, it is necessary to check whether the machine tool spindle is If there is a fault, replace the spindle bearing.

4. The axial dimensions of the workpieces vary greatly

This is mostly caused by the positioning speed being too fast, the drive and the electromechanical can not keep up with the rhythm; the carriage screw and the bearing are too tight and stuck; the tool holder cannot lock the tool, the programming head and tail do not respond or the tool compensation is not banned ; The system electronic gear ratio or step angle setting is wrong. The solution is to adjust the positioning speed properly to make the equipment run at the rated frequency; readjust the clearance between the screw and the bearing; check whether the turbine worm inside the tool holder is worn; improve the program and processing technology; and adjust the electronic gear and step Parameters of the angle of the photographer and so on.

cnc CNC processing plant

5. The processing arc size is not in place

This is because the machine tool components are resonant; the processing technology and parameter settings are not fair, the feed speed is too large, and the arc processing is out of step; the screw is too loose or too tight to cause out of step; and the synchronous belt is caused by wear. It requires the operator to reverse the frequency of the resonant component; set a fair processing technology to reduce the feed rate in an appropriate amount; adjusting the screw clearance and changing the synchronization bring the solution to this problem.

6. Occasionally the workpieces are out of tolerance in batch production

The possible reasons include loose clamping or dimensional change; the CNC system is disturbed. The clamping method of improving the work piece should be used to increase the firmness of the clamping and minimize the possible dimensional changes; discharge electromagnetic interference from the outside and inside, affecting the normal operation of the CNC system. For example, strong electric cables that will cause strong electric field interference are isolated from the signal lines of weak electric signals, and anti-interference absorption capacitors are added and shielded lines are used for isolation.

7. The size of each process increases or decreases

This phenomenon occurs because the programming error; the system parameters and configuration are unfair; the mechanical transmission components have regular periodic changes. Need to locate the dial indicator at the starting point of the program, check whether the carriage returns to the starting point after the program ends, and check whether the program instructions are executed according to the requested trajectory; modify the unfair system parameters and configuration; also check the machine tool transmission department Whether the parts are damaged or not, whether the gear coupling is uniform, and the periodically changing faults are eliminated.

8. The dimensional changes caused by the system are not messy

The main reason for this problem is that the system is damaged or the parameter setting is unfair, or it is subject to interference from the outside; the impedance mismatch between the system and the driver or the signal transmission is abnormal; the operating voltage is unstable.

When the operator confirms that the system is not damaged, it is necessary to adjust the cutting speed in an appropriate amount to check whether the signal generated by the pulse is lost or added; to ensure the reliable connection of the ground wire, install an anti-interference absorption capacitor at the pulse output contact of the driver, and select suitable The type of capacitor; check whether the signal connection line between the system and the driver is reliable, with or without shielding function; install voltage stabilizing equipment.

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