Troubleshooting Demag Crane Superstructure Function Issues

[MikePhua]

Crane operators rely on the smooth operation of all crane functions to perform lifting tasks efficiently. When the superstructure functions of a Demag crane, such as the boom extension, rotation, and other critical controls, fail to operate correctly, it can cause delays and safety concerns on the job site. This article outlines steps to troubleshoot and resolve issues when the superstructure functions of a Demag crane are not working.
Symptoms of the Issue
When the superstructure functions fail on a Demag crane, operators may experience the following symptoms:

• The crane's boom does not extend or retract.
  
• The superstructure does not rotate.
  
• The crane is unable to lift or lower its load.
  
• Warning lights or error codes may be displayed on the control panel.
  

Step-by-Step Troubleshooting

1. Check the Power Supply
   The first thing to check when the superstructure functions fail is the crane's power supply. Ensure that the crane is receiving power and that the main battery is charged. A low battery or faulty electrical connections can prevent various systems, including the superstructure, from functioning correctly.
   • Inspect the battery voltage and replace or charge the battery as necessary.
     
   • Ensure all electrical connections are secure and free of corrosion.
     
2. Inspect the Hydraulic System
   The superstructure functions on a Demag crane are powered by hydraulic systems. If the hydraulics are not functioning properly, the crane will not be able to perform certain tasks, including extending the boom or rotating the superstructure.
   • Check the hydraulic fluid level and ensure it is within the recommended range. Low hydraulic fluid can cause the crane to fail to perform tasks.
     
   • Inspect the hydraulic hoses for any signs of wear or damage. Leaks or cracks in the hydraulic lines can lead to a loss of pressure, resulting in malfunctioning functions.
     
   • Test the hydraulic pumps to make sure they are operating properly and providing the necessary pressure to the crane's superstructure.
     
3. Examine the Control System
   The crane's control system, including the joystick or buttons used by the operator, could be malfunctioning. If the control system is not responding or sending signals to the crane’s functions, it can cause the superstructure to stop working.
   • Inspect the control panel and any associated wiring for signs of damage, wear, or loose connections.
     
   • If the control system displays error codes, consult the crane’s manual or a technician to interpret the codes and determine the exact issue.
     
4. Check the Hydraulic Valves
   The hydraulic valves control the flow of hydraulic fluid to various parts of the crane. If one or more of these valves are malfunctioning or clogged, the superstructure may fail to perform its functions.
   • Inspect the hydraulic valves to ensure they are not clogged with dirt or debris.
     
   • Test the operation of the valves using a hydraulic pressure gauge to ensure they are delivering the correct pressure to the superstructure.
     
5. Look for Obstructions or Mechanical Failures
   Sometimes, mechanical failures or physical obstructions may prevent the superstructure from moving. This can include issues with the crane’s boom, rotation system, or other critical components.
   • Check the crane's boom and rotation systems for any signs of mechanical damage, wear, or obstructions.
     
   • Inspect the slew ring and bearings to ensure smooth rotation. Any damage to these parts could cause the crane's rotation to fail.
     
6. Scan for Error Codes
   Modern cranes like the Demag models come with onboard diagnostic systems. If your crane’s superstructure is not functioning properly, an error code might be displayed on the control panel.
   • Use a diagnostic tool or consult a technician to scan the crane’s control system for error codes.
     
   • The error codes will point to the specific issues with the hydraulic, electrical, or mechanical systems that are preventing the superstructure functions from working.
     
7. Consult the Service Manual
   If you are unable to resolve the issue after performing the basic troubleshooting steps, it is advisable to consult the crane’s service manual. The manual will provide additional information on the crane’s hydraulic and electrical systems, along with recommended repair procedures.
   

Additional Tips

• Maintenance: Regular maintenance is key to preventing such issues. Ensure the crane undergoes regular checks, including hydraulic system maintenance, electrical system inspections, and parts replacements as needed.
  
• Professional Assistance: If the problem persists or if you are unable to diagnose the issue, it is always a good idea to contact Demag’s authorized service provider for professional assistance.
  

Conclusion
Superstructure functions not working on a Demag crane can result from a variety of issues, ranging from power supply problems to hydraulic or mechanical failures. By systematically checking the power supply, hydraulic system, control systems, and other critical components, operators can often identify and resolve the issue. However, when troubleshooting proves difficult, professional assistance is always recommended to ensure the crane’s safe and efficient operation.