CNC press brakes are extensively used in sheet metal processing, yet they inevitably encounter various faults. This article delves into the common fault types of CNC press brakes and provides corresponding solutions to effectively address these issues.
Mechanical Faults
Fault 1: Excessive Clearance Between Slider and Guide Rail, Causing Abnormal Noise
- Cause: The guide rail has been worn due to prolonged use, increasing the clearance.
- Solution: Inspect the wear level of the guide rail pressure plate. Depending on the extent of the wear, decide whether to replace the guide rail pressure plate and readjust to meet the required clearance specifications.
Fault 2: Backgauge Transmission Failure
- Cause: The key strip of the transmission shaft and synchronous pulley has disengaged, or the synchronous belt has slipped.
- Solution: Reassemble the key strip and synchronous belt, then inspect the electrical components to ensure proper function.
Fault 3: Excessive Parallelism Deviation Between Backgauge Beam Linear Guide and Mold Center Line
- Cause: Incorrect orthogonality of the backgauge beam, improper installation of the backgauge, or misalignment of the mold center line.
- Solution: Loosen the X-axis synchronous belt and readjust within the tolerance range for parallelism. Reinstall the synchronous belt accordingly.
Fault 4: Loose Connection Between Cylinder and Slider, Causing Inaccurate Bending Angle or Failure to Locate Reference Point
- Cause: Loose connection nuts or a bent cylinder sleeve.
- Solution: Recheck and tighten the nuts connecting the slider and cylinder. If the cylinder sleeve is bent, replace the sleeve.
Hydraulic Faults
Fault 1: No Pressure in Hydraulic System
- Cause: The solenoid coil of the proportional relief valve is not energized, the voltage of the proportional solenoid coil is incorrect, the plug-in valve is stuck, the main valve core is stuck, or the damping orifice is blocked.
- Solution:
- Check if the solenoid coil is energized and if the voltage is within specifications.
- Disassemble and clean the relief valve, then reinstall it.
- Check the plug-in valve and main valve core for any blockage and remove any obstructions in the damping orifice.
Fault 2: Prolonged Pause When Switching from Fast to Slow Movement of the Slider
- Cause: The oil level in the tank is too low, the filling port is not submerged, or there is insufficient filling due to air being drawn into the upper chamber of the cylinder during fast forward movement.
- Solution:
- Check and ensure the oil level in the tank is adequate.
- Verify that the filling port is submerged.
- Eliminate the cause of insufficient filling.
Electrical Faults
Fault 1: No Display on Electrical Control System
- Cause: Power is disconnected, a fuse is blown, circuit board malfunction, or poor connections.
- Solution:
- Check if the power supply is connected.
- Inspect the fuses and replace any that are blown.
- Examine the circuit board for faults and replace if necessary.
- Ensure all connections are secure.
Fault 2: Loss of CNC System Parameters
- Cause: Depleted battery, unsaved parameters, or software corruption.
- Solution:
- Replace the battery.
- Restore parameter backups.
- Reinstall the software.
Fault 3: Servo Motor Overheat Alarm
- Cause: Motor overload, poor heat dissipation, or encoder malfunction.
- Solution:
- Reduce the processing load.
- Improve heat dissipation.
- Check and replace the encoder if faulty.
Fault 4: Unstable CNC System Operation
- Cause: Electromagnetic interference, software errors, or hardware malfunctions.
- Solution:
- Identify and isolate the sources of electromagnetic interference.
- Update the software.
- Check the hardware and replace any faulty components.
Prevention and Maintenance
To minimize the frequency of CNC press brake faults, regular preventive maintenance is crucial:
- Lubrication: Regularly lubricate the guide rails and sliding components.
- Hydraulic System: Inspect the hydraulic system to ensure there are no leaks.
- Electrical Connections: Check all electrical connections to ensure they are secure.
- Cleaning: Keep the machine clean and free of dust and debris.
- Maintenance Plan: Follow the manufacturer’s recommended maintenance schedule.
Conclusion
By thoroughly analyzing the common faults of CNC press brakes, this guide effectively aids users in troubleshooting and resolving issues. Adhering to preventive and maintenance measures helps extend the machine’s lifespan, enhance production efficiency, and ensure product quality.
Mechanical Faults
Fault 1: Excessive Clearance Between Slider and Guide Rail, Causing Abnormal Noise
- Cause: The guide rail has been worn due to prolonged use, increasing the clearance.
- Solution: Inspect the wear level of the guide rail pressure plate. Depending on the extent of the wear, decide whether to replace the guide rail pressure plate and readjust to meet the required clearance specifications.
Fault 2: Backgauge Transmission Failure
- Cause: The key strip of the transmission shaft and synchronous pulley has disengaged, or the synchronous belt has slipped.
- Solution: Reassemble the key strip and synchronous belt, then inspect the electrical components to ensure proper function.
Fault 3: Excessive Parallelism Deviation Between Backgauge Beam Linear Guide and Mold Center Line
- Cause: Incorrect orthogonality of the backgauge beam, improper installation of the backgauge, or misalignment of the mold center line.
- Solution: Loosen the X-axis synchronous belt and readjust within the tolerance range for parallelism. Reinstall the synchronous belt accordingly.
Fault 4: Loose Connection Between Cylinder and Slider, Causing Inaccurate Bending Angle or Failure to Locate Reference Point
- Cause: Loose connection nuts or a bent cylinder sleeve.
- Solution: Recheck and tighten the nuts connecting the slider and cylinder. If the cylinder sleeve is bent, replace the sleeve.
Hydraulic Faults
Fault 1: No Pressure in Hydraulic System
- Cause: The solenoid coil of the proportional relief valve is not energized, the voltage of the proportional solenoid coil is incorrect, the plug-in valve is stuck, the main valve core is stuck, or the damping orifice is blocked.
- Solution:
- Check if the solenoid coil is energized and if the voltage is within specifications.
- Disassemble and clean the relief valve, then reinstall it.
- Check the plug-in valve and main valve core for any blockage and remove any obstructions in the damping orifice.
Fault 2: Prolonged Pause When Switching from Fast to Slow Movement of the Slider
- Cause: The oil level in the tank is too low, the filling port is not submerged, or there is insufficient filling due to air being drawn into the upper chamber of the cylinder during fast forward movement.
- Solution:
- Check and ensure the oil level in the tank is adequate.
- Verify that the filling port is submerged.
- Eliminate the cause of insufficient filling.
Electrical Faults
Fault 1: No Display on Electrical Control System
- Cause: Power is disconnected, a fuse is blown, circuit board malfunction, or poor connections.
- Solution:
- Check if the power supply is connected.
- Inspect the fuses and replace any that are blown.
- Examine the circuit board for faults and replace if necessary.
- Ensure all connections are secure.
Fault 2: Loss of CNC System Parameters
- Cause: Depleted battery, unsaved parameters, or software corruption.
- Solution:
- Replace the battery.
- Restore parameter backups.
- Reinstall the software.
Fault 3: Servo Motor Overheat Alarm
- Cause: Motor overload, poor heat dissipation, or encoder malfunction.
- Solution:
- Reduce the processing load.
- Improve heat dissipation.
- Check and replace the encoder if faulty.
Fault 4: Unstable CNC System Operation
- Cause: Electromagnetic interference, software errors, or hardware malfunctions.
- Solution:
- Identify and isolate the sources of electromagnetic interference.
- Update the software.
- Check the hardware and replace any faulty components.
Prevention and Maintenance
To minimize the frequency of CNC press brake faults, regular preventive maintenance is crucial:
- Lubrication: Regularly lubricate the guide rails and sliding components.
- Hydraulic System: Inspect the hydraulic system to ensure there are no leaks.
- Electrical Connections: Check all electrical connections to ensure they are secure.
- Cleaning: Keep the machine clean and free of dust and debris.
- Maintenance Plan: Follow the manufacturer’s recommended maintenance schedule.
Conclusion
By thoroughly analyzing the common faults of CNC press brakes, this guide effectively aids users in troubleshooting and resolving issues. Adhering to preventive and maintenance measures helps extend the machine’s lifespan, enhance production efficiency, and ensure product quality.
