Operating a bending machine efficiently requires understanding and troubleshooting common issues that may arise. This guide covers typical problems such as continuous pressure application, reduced bending speed, and other mechanical and hydraulic faults. By following these troubleshooting steps, you can ensure your bending machine operates smoothly and efficiently.
Troubleshooting Continuous Pressure Application
Problem: Bending Machine Continues to Apply Pressure After Startup
When the bending machine continues to apply pressure after startup and the foot pedal does not respond to move the slider up, several issues could be causing this problem.
Possible Causes:
1. Throttle Valve Failure: The throttle valve might be stuck or malfunctioning.
2. Air in the Hydraulic Cylinder: Air may have entered the hydraulic system.
3. Return Oil Pipe Position: The return oil pipe may not be submerged below the oil level, causing air to mix with the hydraulic oil.
Solutions:
1. Check the Throttle Valve:
- Disconnect the pressure relay. If the machine can move up but not down, the throttle valve is likely the issue.
- Clean or replace the throttle valve as necessary.
2. Remove Air from the Hydraulic Cylinder:
- Inspect the hydraulic cylinder for any signs of air entry.
- Bleed the air from the hydraulic system according to the manufacturer's instructions.
3. Adjust Return Oil Pipe:
- Ensure that the return oil pipe is submerged below the oil surface.
- If not, reposition the pipe to prevent air from entering the hydraulic oil.
Troubleshooting Reduced Bending Speed
Problem: Bending Speed Significantly Decreases
A noticeable decrease in the bending speed of the machine can affect productivity and bending quality.
Possible Causes:
1. Insufficient Pressure: The system pressure might be lower than required.
2. System Leakage: There could be a leak in the hydraulic system.
Solutions:
1. Check System Pressure:
- Inspect the pressure gauge. If the pressure is below the required level, the issue might be with the relief valve or the hydraulic pump.
- If the relief valve is faulty, replace it. If the pump is worn out, it might need servicing or replacement.
2. Inspect for System Leaks:
- Check all hydraulic lines for leaks.
- Examine critical components such as the pump, relief valve, and actuators (cylinders) for signs of leakage.
- Repair or replace any leaking components.
General Hydraulic Bending Machine Inspection Methods
1. Electrical and Solenoid Valve Check
1. Power On:
- Start the machine and disconnect all solenoid valve plugs.
2. Manual Valve Operation:
- Manually press the valve cores according to the hydraulic schematic.
- If the machine responds, check the electrical system and solenoid valve coils.
- If there is no response, inspect the entire hydraulic circuit.
2. Hydraulic System Check
1. Check Oil Level and Motor Rotation:
- Ensure the hydraulic oil level is adequate and that the motor rotates correctly.
2. Evaluate Hydraulic Valves:
- Inspect the main relief valve and other hydraulic valves for proper operation.
3. Solenoid Valve Inspection:
- Ensure the solenoid valve cores move freely and that the seals are intact.
4. Check Cartridge Check Valves:
- Inspect for proper sealing of the cartridge check valves.
3. Mechanical Components Check
1. Guide Rails:
- Ensure the guide rails are not jammed.
2. Synchronization Shaft:
- Check the synchronization shaft for any obstructions.
4. Hydraulic Cylinder Check
1. Cylinder Function:
- Inspect the hydraulic cylinders to ensure they are not stuck.
2. Seal Integrity:
- Check the seals for damage that could cause internal leakage.
5. Secondary Return Control
1. Return Oil Pressure:
- Verify that the return oil pressure is correctly set and functioning.
Other Common Bending Machine Issues
Issue: No Response When Pressing the Foot Pedal
Possible Causes:
1. Power Supply Issue: There could be a problem with the power supply line.
2. Faulty Foot Pedal Switch: The foot pedal switch may be damaged.
Solutions:
1. Check Power Supply:
- Ensure that the power supply is connected and functioning properly.
2. Inspect Foot Pedal Switch:
- Test the foot pedal switch and replace it if necessary.
Issue: Abnormal Hydraulic Return Flow
Possible Causes:
1. Continuous Pressurization: The system remains pressurized when the switch is engaged.
2. Obstruction in Return Line: Foreign objects may be obstructing the hydraulic return line.
Solutions:
1. Observe Hydraulic Flow:
- While pressing the switch, observe the return flow in the oil tank.
2. Inspect and Clean Return Line:
- Remove and inspect the return line for obstructions.
- Clean any debris found in the return line.
Ensuring Optimal Performance and Safety
Safety Precautions:
Wear Protective Gear:
- Always wear safety glasses, gloves, and appropriate safety shoes.
Pre-Operation Checks:
- Inspect all electrical connections, ensure proper grounding, and check the hydraulic oil level and motor rotation.
Regular Maintenance:
- Follow a regular maintenance schedule, checking for wear and tear on all machine components.
Preventive Maintenance:
Monitor Operation:
- Continuously monitor the machine during operation for any unusual sounds or behaviors.
Preventive Checks:
- Regularly inspect hydraulic lines, valves, and mechanical components to prevent unexpected breakdowns.
Conclusion
Properly troubleshooting and maintaining a CNC bending machine involves understanding its hydraulic and electrical systems. By following the detailed steps for identifying and solving common issues, operators can ensure their machines run smoothly and efficiently. Regular maintenance and adherence to safety protocols will also help prolong the life of the machine and maintain high-quality bending results.
