CNC lathes can encounter a variety of problems during use, involving various aspects such as the drive system, tool holder, machining accuracy, electrical system, and auxiliary devices. The following are specific issues and solutions:
Transmission System Problems
► Fault Symptoms: Mechanical components of the CNC lathe fail to move to the specified position, operation is interrupted, positioning accuracy decreases, backlash increases, mechanical creep, and bearing noise increases.
► Cause Analysis: Reduced CNC machine tool motion quality, such as worn, loose components, or insufficient lubrication.
Solution: Adjust the preload of each kinematic joint on the CNC lathe, correct loose links, improve motion accuracy, adjust compensation links, and enhance lubrication and maintenance.
Tool Holder Problems
► Malfunction Symptoms: The CNC lathe tool holder does not position the tool change correctly, rotates continuously, does not lock tightly, or is too loose after tool change.
► Cause Analysis: Damaged CNC lathe Hall effect element, misaligned transmitter disk, insufficient system anti-lock time, mechanical locking mechanism malfunction, etc.
► Solution: Replace the CNC machine tool Hall element or the signal disk, adjust the position of the signal disk, adjust the system anti-lock time parameters, disassemble the tool holder to adjust the mechanism, and check whether the positioning pin is broken.
Machining Accuracy Issues
► Symptoms: Inaccurate workpiece dimensions, poor surface finish, tapered ends, and unsatisfactory arc machining results.
► Cause Analysis: CNC lathe tool wear, machine resonance, unstable placement, crawling, poor machining process, spindle bearing wear, and programming errors.
► Solution: Resharpen the CNC machine tool or select a better tool, adjust the machine level, lay a foundation, and ensure a stable and secure position. Improve lubrication and maintenance, select appropriate processes and cutting parameters, overhaul the spindle and replace the bearings, and check and correct the program.
Electrical System Problems
► Fault Symptoms: CNC machine servo system failure (e.g., position deviation, immobility), program operation anomalies (e.g., freeze, execution error), system alarms, etc.
► Cause Analysis: Loose or damaged CNC lathe wiring, servo motor and driver connection issues, program syntax errors, poor control wiring contact, etc.
► Solution: Check and tighten the CNC machine wiring, restart the system and recalibrate the origin, clear the CNC system memory, check the control wiring contact, and troubleshoot based on the alarm code.
Auxiliary Device Problems
► Symptoms: Low or no coolant in the CNC machine tool, poor chip removal, hydraulic system malfunction, or pneumatic system failure.
► Cause Analysis: Coolant pipes clogged by chip debris from the CNC lathe, chip removal malfunction, hydraulic pump wear, or poor lubrication in the pneumatic system.
► Solution: Install a filter or use sheet metal to enclose the drain holes on the CNC lathe. Use an air gun to blow out the pipes. Clean or replace the hydraulic pump. Regularly clean the water separator, air filter, and oil mist collector.
