CNC hydraulic press brakes are crucial for precision metal bending operations. However, synchronization issues between the dual axes (Y1 and Y2) can significantly affect the quality of the bends. This article explores the causes of synchronization faults, common press brake issues, and their solutions.
Causes of Synchronization Faults in Dual-Axis CNC Hydraulic Press Brakes
Synchronization faults in CNC hydraulic press brakes occur when the Y1 and Y2 axes do not move synchronously, leading to inconsistent bending results. Here are the primary causes and their solutions:
1. Reference Point Failure at Startup
When the press brake is powered on, it needs to locate reference points to set the initial positions of the Y1 and Y2 axes. If one side fails to find its reference point, it causes a positional deviation, resulting in asynchronous movement during the downward stroke.
Solution:
- Check Linear Scale Connections: Ensure that the wiring of the linear scales is secure and free from faults.
- Recalibrate Reference Points: Restart the machine and perform the reference point finding procedure again.
2. Inconsistent Gain and Downward Voltage Settings
The gain and voltage settings control the descent speed of the Y1 and Y2 axes. If these settings differ, it causes the rams to move at different speeds, leading to synchronization issues.
Solution:
- Verify and Adjust Settings: Check the descent speeds of both axes and adjust the gain and voltage settings to ensure they are synchronized.
3. Uneven Tension in Left and Right Guide Plates
The guide plates direct the movement of the rams. If the tension in the left and right guide plates is uneven, it causes different friction levels, leading to asynchronous movement.
Solution:
- Inspect and Adjust Guide Plates: Ensure that the tension in the left and right guide plates is even and adjust if necessary.
4. Unequal Back Pressure in Left and Right Cylinders
Back pressure in the hydraulic cylinders keeps the pistons in their designated positions. Disparities in back pressure between the left and right cylinders can result in synchronization faults.
Solution:
- Check and Balance Back Pressure: Ensure that the back pressure in both the left and right cylinders is equal and make adjustments as needed.
5. Linear Scale Connection Issues
Loose or faulty connections in the linear scale wiring can cause interruptions in reading the current position, leading to synchronization issues.
Solution:
- Inspect Linear Scale Wiring: Check for any loose or faulty connections in the linear scale wiring and secure or replace them as needed.
Common CNC Press Brake Faults and Their Solutions
In addition to synchronization issues, CNC press brakes can encounter other common faults. Here are some of the typical problems and how to address them:
Fault 1: Low-Pressure Circuit Breaker Trips After Oil Pump Starts
Solution:
- Check for Power Supply Issues: Ensure there are no phase losses in the power supply.
- Inspect High-Pressure Filter: Check if the high-pressure filter is clogged, causing excessive current draw by the oil pump motor.
- Verify Circuit Breaker Settings: Ensure that the high-pressure circuit breaker is set correctly and not too low.
Fault 2: Unable to Find Reference Point After Startup
Solution:
- Inspect Linear Scale Reader Head: Check if the reader head of the linear scale has become detached, preventing it from aligning with the reference point.
- Ensure Proper Shutdown Procedure: Confirm that the previous operator followed the correct shutdown procedure by stopping the slider at the top dead center and manually aligning the molds before the next startup.
Fault 3: CNC System Display Is Blank or Gray with Flashing Programming Key Indicator
Solution:
- Check Display Connections: Ensure that all connections to the display and control panel are secure.
- Inspect Power Supply: Verify that the control system is receiving the correct power supply.
- Consult Manufacturer Support: If the issue persists, contact the manufacturer’s technical support for further assistance.
Tips for Maintaining CNC Press Brakes
Regular Inspection and Maintenance
To prevent synchronization faults and other issues, regularly inspect and maintain the press brake. This includes checking electrical connections, hydraulic systems, and mechanical components.
Proper Training for Operators
Ensure that all operators are adequately trained on the correct startup, shutdown, and operational procedures for the press brake. This reduces the likelihood of user errors that can cause synchronization faults and other issues.
Timely Professional Assistance
If the above solutions do not resolve the issues, seek assistance from the manufacturer’s technical support team. They can provide expert guidance and tailored solutions for your specific press brake model.
Conclusion
Synchronization faults and common issues in CNC hydraulic press brakes can significantly impact bending quality and productivity. By understanding the causes of synchronization faults—such as reference point calibration, gain and voltage settings, guide plate tension, and back pressure—you can implement effective solutions to maintain synchronized ram movement.
Regular maintenance, proper operator training, and timely professional assistance are key to ensuring your CNC press brake operates smoothly and produces high-quality parts consistently. Following the troubleshooting steps outlined in this guide will help you address synchronization issues and optimize your bending processes.
